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Liu SZ, Guo WT, Chen H, Yin ZX, Tang XG, Sun QJ. Recent Progress on Flexible Self-Powered Tactile Sensing Platforms for Health Monitoring and Robotics. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2405520. [PMID: 39128137 DOI: 10.1002/smll.202405520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2024] [Indexed: 08/13/2024]
Abstract
Over the past decades, tactile sensing technology has made significant advances in the fields of health monitoring and robotics. Compared to conventional sensors, self-powered tactile sensors do not require an external power source to drive, which makes the entire system more flexible and lightweight. Therefore, they are excellent candidates for mimicking the tactile perception functions for wearable health monitoring and ideal electronic skin (e-skin) for intelligent robots. Herein, the working principles, materials, and device fabrication strategies of various self-powered tactile sensing platforms are introduced first. Then their applications in health monitoring and robotics are presented. Finally, the future prospects of self-powered tactile sensing systems are discussed.
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Affiliation(s)
- Shu-Zheng Liu
- School of Physics and Optoelectronic Engineering & Guangdong Provincial Key Laboratory of Sensing Physics and System Integration Applications, Guangdong University of Technology, Guangzhou, 510006, China
| | - Wen-Tao Guo
- School of Physics and Optoelectronic Engineering & Guangdong Provincial Key Laboratory of Sensing Physics and System Integration Applications, Guangdong University of Technology, Guangzhou, 510006, China
| | - Hao Chen
- School of Physics and Optoelectronic Engineering & Guangdong Provincial Key Laboratory of Sensing Physics and System Integration Applications, Guangdong University of Technology, Guangzhou, 510006, China
| | - Zhi-Xiang Yin
- School of Physics and Optoelectronic Engineering & Guangdong Provincial Key Laboratory of Sensing Physics and System Integration Applications, Guangdong University of Technology, Guangzhou, 510006, China
| | - Xin-Gui Tang
- School of Physics and Optoelectronic Engineering & Guangdong Provincial Key Laboratory of Sensing Physics and System Integration Applications, Guangdong University of Technology, Guangzhou, 510006, China
| | - Qi-Jun Sun
- School of Physics and Optoelectronic Engineering & Guangdong Provincial Key Laboratory of Sensing Physics and System Integration Applications, Guangdong University of Technology, Guangzhou, 510006, China
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2
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Wu Y, Lin T, Santos E, Ahn D, Marson R, Sarker P, Chen X, Gubbels F, Shephard NE, Mohler C, Wei T, Kuo TC, Chen Z. Molecular behavior of silicone adhesive at buried polymer interface studied by molecular dynamics simulation and sum frequency generation vibrational spectroscopy. SOFT MATTER 2024; 20:4765-4775. [PMID: 38841820 DOI: 10.1039/d4sm00407h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2024]
Abstract
Silicones have excellent material properties and are used extensively in many applications, ranging from adhesives and lubricants to electrical insulation. To ensure strong adhesion of silicone adhesives to a wide variety of substrates, silane-based adhesion promotors are typically blended into the silicone adhesive formulation. However, little is known at the molecular level about the true silane adhesion promotion mechanism, which limits the ability to develop even more effective adhesion promoters. To understand the adhesion promotion mechanism of silane molecules at the molecular level, this study has used sum frequency generation vibrational spectroscopy (SFG) to determine the behavior of (3-glycidoxypropyl)trimethoxy silane (γ-GPS) at the buried interface between poly(ethylene terephthalate) (PET) and a bulk silicone adhesive. To complement and extend the SFG results, atomistic molecular dynamics (MD) simulations were applied to investigate molecular behavior and interfacial interaction of γ-GPS at the silicone/PET interface. Free energy computations were used to study the γ-GPS interaction in the sample system and determine the γ-GPS interfacial segregation mechanism. Both experiments and simulations consistently show that γ-GPS molecules prefer to segregate at the interface between PET and PDMS. The methoxy groups on γ-GPS molecules orient toward the PDMS polymer phase. The consistent picture of interfacial structure emerging from both simulation and experiment provides enhanced insight on how γ-GPS behaves in the silicone - PET system and illustrates why γ-GPS could improve the adhesion of silicone adhesive, leading to further understanding of silicone adhesion mechanisms useful in the design of silicone adhesives with improved performance.
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Affiliation(s)
- Yuchen Wu
- Department of Chemistry, University of Michigan, MI 48109, USA.
- Department of Macromolecular Science and Engineering, University of Michigan, MI 48109, USA
| | - Ting Lin
- Department of Chemistry, University of Michigan, MI 48109, USA.
- Department of Macromolecular Science and Engineering, University of Michigan, MI 48109, USA
| | | | - Dongchan Ahn
- The Dow Chemical Company, Midland, MI 48674, USA
| | - Ryan Marson
- The Dow Chemical Company, Midland, MI 48674, USA
| | - Pranab Sarker
- Department of Biomedical Engineering, University of South Carolina, Columbia, SC 29208, USA.
- Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208, USA
| | - Xiaoyun Chen
- The Dow Chemical Company, Midland, MI 48674, USA
| | | | | | - Carol Mohler
- The Dow Chemical Company, Midland, MI 48674, USA
| | - Tao Wei
- Department of Biomedical Engineering, University of South Carolina, Columbia, SC 29208, USA.
- Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208, USA
| | - Tzu-Chi Kuo
- The Dow Chemical Company, Midland, MI 48674, USA
| | - Zhan Chen
- Department of Chemistry, University of Michigan, MI 48109, USA.
- Department of Macromolecular Science and Engineering, University of Michigan, MI 48109, USA
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Keshyagol K, Hiremath S, H. M. V, Kini U. A, Naik N, Hiremath P. Optimizing Capacitive Pressure Sensor Geometry: A Design of Experiments Approach with a Computer-Generated Model. SENSORS (BASEL, SWITZERLAND) 2024; 24:3504. [PMID: 38894295 PMCID: PMC11175090 DOI: 10.3390/s24113504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 05/04/2024] [Accepted: 05/08/2024] [Indexed: 06/21/2024]
Abstract
This study presents a comprehensive investigation into the design and optimization of capacitive pressure sensors (CPSs) for their integration into capacitive touch buttons in electronic applications. Using the Finite Element Method (FEM), various geometries of dielectric layers were meticulously modeled and analyzed for their capacitive and sensitivity parameters. The flexible elastomer polydimethylsiloxane (PDMS) is used as a diaphragm, and polyvinylidene fluoride (PVDF) is a flexible material that acts as a dielectric medium. The Design of Experiment (DoE) techniques, aided by statistical analysis, were employed to identify the optimal geometric shapes of the CPS model. From the prediction using the DoE approach, it is observed that the cylindrical-shaped dielectric medium has better sensitivity. Using this optimal configuration, the CPS was further examined across a range of dielectric layer thicknesses to determine the capacitance, stored electrical energy, displacement, and stress levels at uniform pressures ranging from 0 to 200 kPa. Employing a 0.1 mm dielectric layer thickness yields heightened sensitivity and capacitance values, which is consistent with theoretical efforts. At a pressure of 200 kPa, the sensor achieves a maximum capacitance of 33.3 pF, with a total stored electric energy of 15.9 × 10-12 J and 0.468 pF/Pa of sensitivity for 0.1 dielectric thickness. These findings underscore the efficacy of the proposed CPS model for integration into capacitive touch buttons in electronic devices and e-skin applications, thereby offering promising advancements in sensor technology.
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Affiliation(s)
- Kiran Keshyagol
- Department of Mechatronics, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; (K.K.); (S.H.)
| | - Shivashankarayya Hiremath
- Department of Mechatronics, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; (K.K.); (S.H.)
- Survivability Signal Intelligence Research Center, Hanyang University, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Vishwanatha H. M.
- Department of Mechanical and Industrial Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; (V.H.M.); (A.K.U.); (N.N.)
| | - Achutha Kini U.
- Department of Mechanical and Industrial Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; (V.H.M.); (A.K.U.); (N.N.)
| | - Nithesh Naik
- Department of Mechanical and Industrial Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; (V.H.M.); (A.K.U.); (N.N.)
| | - Pavan Hiremath
- Department of Mechanical and Industrial Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India; (V.H.M.); (A.K.U.); (N.N.)
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Song Y, Hu C, Wang Z, Wang L. Silk-based wearable devices for health monitoring and medical treatment. iScience 2024; 27:109604. [PMID: 38628962 PMCID: PMC11019284 DOI: 10.1016/j.isci.2024.109604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024] Open
Abstract
Previous works have focused on enhancing the tensile properties, mechanical flexibility, biocompatibility, and biodegradability of wearable devices for real-time and continuous health management. Silk proteins, including silk fibroin (SF) and sericin, show great advantages in wearable devices due to their natural biodegradability, excellent biocompatibility, and low fabrication cost. Moreover, these silk proteins possess great potential for functionalization and are being explored as promising candidates for multifunctional wearable devices with sensory capabilities and therapeutic purposes. This review introduces current advancements in silk-based constituents used in the assembly of wearable sensors and adhesives for detecting essential physiological indicators, including metabolites in body fluids, body temperature, electrocardiogram (ECG), electromyogram (EMG), pulse, and respiration. SF and sericin play vital roles in addressing issues related to discomfort reduction, signal fidelity improvement, as well as facilitating medical treatment. These developments signify a transition from hospital-centered healthcare toward individual-centered health monitoring and on-demand therapeutic interventions.
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Affiliation(s)
- Yu Song
- Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Chuting Hu
- Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Zheng Wang
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Lin Wang
- Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Hubei Key Laboratory of Regenerative Medicine and Multi-disciplinary Translational Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Hubei Provincial Engineering Research Center of Clinical Laboratory and Active Health Smart Equipment, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
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Shukla P, Saxena P, Madhwal D, Singh Y, Bhardwaj N, Samal R, Kumar V, Jain VK. Prototyping a wearable and stretchable graphene-on-PDMS sensor for strain detection on human body physiological and joint movements. Mikrochim Acta 2024; 191:301. [PMID: 38709350 DOI: 10.1007/s00604-024-06368-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 04/15/2024] [Indexed: 05/07/2024]
Abstract
In the era of wearable electronic devices, which are quite popular nowadays, our research is focused on flexible as well as stretchable strain sensors, which are gaining humongous popularity because of recent advances in nanocomposites and their microstructures. Sensors that are stretchable and flexible based on graphene can be a prospective 'gateway' over the considerable biomedical speciality. The scientific community still faces a great problem in developing versatile and user-friendly graphene-based wearable strain sensors that satisfy the prerequisites of susceptible, ample range of sensing, and recoverable structural deformations. In this paper, we report the fabrication, development, detailed experimental analysis and electronic interfacing of a robust but simple PDMS/graphene/PDMS (PGP) multilayer strain sensor by drop casting conductive graphene ink as the sensing material onto a PDMS substrate. Electrochemical exfoliation of graphite leads to the production of abundant, fast and economical graphene. The PGP sensor selective to strain has a broad strain range of ⁓60%, with a maximum gauge factor of 850, detection of human physiological motion and personalized health monitoring, and the versatility to detect stretching with great sensitivity, recovery and repeatability. Additionally, recoverable structural deformation is demonstrated by the PGP strain sensors, and the sensor response is quite rapid for various ranges of frequency disturbances. The structural designation of graphene's overlap and crack structure is responsible for the resistance variations that give rise to the remarkable strain detection properties of this sensor. The comprehensive detection of resistance change resulting from different human body joints and physiological movements demonstrates that the PGP strain sensor is an effective choice for advanced biomedical and therapeutic electronic device utility.
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Affiliation(s)
- Prashant Shukla
- Amity Institute of Advanced Research and Studies (Materials & Devices), Amity University, Sector-125, Noida, 201303, U.P, India.
| | - Pooja Saxena
- G. L. Bajaj Institute of Technology and Management, Greater Noida, 201306, U.P., India
| | - Devinder Madhwal
- Amity Institute of Advanced Research and Studies (Materials & Devices), Amity University, Sector-125, Noida, 201303, U.P, India
| | - Yugal Singh
- Amity Institute of Advanced Research and Studies (Materials & Devices), Amity University, Sector-125, Noida, 201303, U.P, India
| | - Nitin Bhardwaj
- Amity Institute of Advanced Research and Studies (Materials & Devices), Amity University, Sector-125, Noida, 201303, U.P, India
| | - Rajesh Samal
- Amity Institute of Advanced Research and Studies (Materials & Devices), Amity University, Sector-125, Noida, 201303, U.P, India
| | - Vivek Kumar
- Amity Institute of Advanced Research and Studies (Materials & Devices), Amity University, Sector-125, Noida, 201303, U.P, India
| | - V K Jain
- Amity Institute of Advanced Research and Studies (Materials & Devices), Amity University, Sector-125, Noida, 201303, U.P, India
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Luo X, Tan H, Wen W. Recent Advances in Wearable Healthcare Devices: From Material to Application. Bioengineering (Basel) 2024; 11:358. [PMID: 38671780 PMCID: PMC11048539 DOI: 10.3390/bioengineering11040358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 04/02/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024] Open
Abstract
In recent years, the proliferation of wearable healthcare devices has marked a revolutionary shift in the personal health monitoring and management paradigm. These devices, ranging from fitness trackers to advanced biosensors, have not only made healthcare more accessible, but have also transformed the way individuals engage with their health data. By continuously monitoring health signs, from physical-based to biochemical-based such as heart rate and blood glucose levels, wearable technology offers insights into human health, enabling a proactive rather than a reactive approach to healthcare. This shift towards personalized health monitoring empowers individuals with the knowledge and tools to make informed decisions about their lifestyle and medical care, potentially leading to the earlier detection of health issues and more tailored treatment plans. This review presents the fabrication methods of flexible wearable healthcare devices and their applications in medical care. The potential challenges and future prospectives are also discussed.
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Affiliation(s)
- Xiao Luo
- Department of Physics, The Hong Kong University of Science and Technology, Hong Kong 999077, China;
- HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute (SHCIRI), Futian, Shenzhen 518060, China
| | - Handong Tan
- Department of Individualized Interdisciplinary Program (Advanced Materials), The Hong Kong University of Science and Technology, Hong Kong 999077, China;
| | - Weijia Wen
- Department of Physics, The Hong Kong University of Science and Technology, Hong Kong 999077, China;
- HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute (SHCIRI), Futian, Shenzhen 518060, China
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Kim S, Jeon H, Koo JM, Oh DX, Park J. Practical Applications of Self-Healing Polymers Beyond Mechanical and Electrical Recovery. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2302463. [PMID: 38361378 DOI: 10.1002/advs.202302463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 12/15/2023] [Indexed: 02/17/2024]
Abstract
Self-healing polymeric materials, which can repair physical damage, offer promising prospects for protective applications across various industries. Although prolonged durability and resource conservation are key advantages, focusing solely on mechanical recovery may limit the market potential of these materials. The unique physical properties of self-healing polymers, such as interfacial reduction, seamless connection lines, temperature/pressure responses, and phase transitions, enable a multitude of innovative applications. In this perspective, the diverse applications of self-healing polymers beyond their traditional mechanical strength are emphasized and their potential in various sectors such as food packaging, damage-reporting, radiation shielding, acoustic conservation, biomedical monitoring, and tissue regeneration is explored. With regards to the commercialization challenges, including scalability, robustness, and performance degradation under extreme conditions, strategies to overcome these limitations and promote successful industrialization are discussed. Furthermore, the potential impacts of self-healing materials on future research directions, encompassing environmental sustainability, advanced computational techniques, integration with emerging technologies, and tailoring materials for specific applications are examined. This perspective aims to inspire interdisciplinary approaches and foster the adoption of self-healing materials in various real-life settings, ultimately contributing to the development of next-generation materials.
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Affiliation(s)
- Semin Kim
- Research Center for Bio-based Chemistry, Korea Research Institute of Chemical Technology (KRICT), Ulsan, 44429, Republic of Korea
| | - Hyeonyeol Jeon
- Research Center for Bio-based Chemistry, Korea Research Institute of Chemical Technology (KRICT), Ulsan, 44429, Republic of Korea
| | - Jun Mo Koo
- Department of Organic Materials Engineering, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Dongyeop X Oh
- Research Center for Bio-based Chemistry, Korea Research Institute of Chemical Technology (KRICT), Ulsan, 44429, Republic of Korea
- Department of Polymer Science and Engineering and Program in Environmental and Polymer Engineering, Inha University, Incheon, 22212, Republic of Korea
| | - Jeyoung Park
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul, 04107, Republic of Korea
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Toto E, Lambertini L, Laurenzi S, Santonicola MG. Recent Advances and Challenges in Polymer-Based Materials for Space Radiation Shielding. Polymers (Basel) 2024; 16:382. [PMID: 38337271 DOI: 10.3390/polym16030382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 01/25/2024] [Accepted: 01/27/2024] [Indexed: 02/12/2024] Open
Abstract
Space exploration requires the use of suitable materials to protect astronauts and structures from the hazardous effects of radiation, in particular, ionizing radiation, which is ubiquitous in the hostile space environment. In this scenario, polymer-based materials and composites play a crucial role in achieving effective radiation shielding while providing low-weight and tailored mechanical properties to spacecraft components. This work provides an overview of the latest developments and challenges in polymer-based materials designed for radiation-shielding applications in space. Recent advances in terms of both experimental and numerical studies are discussed. Different approaches to enhancing the radiation-shielding performance are reported, such as integrating various types of nanofillers within polymer matrices and optimizing the materials design. Furthermore, this review explores the challenges in developing multifunctional materials that are able to provide radiation protection. By summarizing the state-of-the-art research and identifying emerging trends, this review aims to contribute to the ongoing efforts to identify polymer materials and composites that are most useful to protect human health and spacecraft performance in the harsh radiation conditions that are typically found during missions in space.
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Affiliation(s)
- Elisa Toto
- Department of Astronautical, Electrical and Energy Engineering, Sapienza University of Rome, Via Salaria 851-881, 00138 Rome, Italy
| | - Lucia Lambertini
- Department of Astronautical, Electrical and Energy Engineering, Sapienza University of Rome, Via Salaria 851-881, 00138 Rome, Italy
| | - Susanna Laurenzi
- Department of Astronautical, Electrical and Energy Engineering, Sapienza University of Rome, Via Salaria 851-881, 00138 Rome, Italy
| | - Maria Gabriella Santonicola
- Department of Chemical Engineering Materials Environment, Sapienza University of Rome, Via del Castro Laurenziano 7, 00161 Rome, Italy
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Cui X, Miao C, Lu S, Liu X, Yang Y, Sun J. Strain Sensors Made of MXene, CNTs, and TPU/PSF Asymmetric Structure Films with Large Tensile Recovery and Applied in Human Health Monitoring. ACS APPLIED MATERIALS & INTERFACES 2023; 15:59655-59670. [PMID: 38085975 DOI: 10.1021/acsami.3c11328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2023]
Abstract
Designing flexible wearable sensors with a wide sensing range, high sensitivity, and high stability is a vulnerable research direction with a futuristic field to study. In this paper, Ti3C2Tx MXene/carbon nanotube (CNT)/thermoplastic polyurethane (TPU)/polysulfone (PSF) composite films with excellent sensor performance were obtained by self-assembly of conductive fillers in TPU/PSF porous films with an asymmetric structure through vacuum filtration, and the porous films were prepared by the phase inversion method. The composite films consist of the upper part with finger-like "cavities" filled by MXene/CNTs, which reduces the microcracks in the conductive network during the tensile process, and the lower part has smaller apertures of a relatively dense resin cortex assisting the recovery process. The exclusive layer structure of the MXene/CNTs/TPU/PSF film sensor, with a thickness of 46.95 μm, contains 0.0339 mg/cm2 single-walled carbon nanotubes (SWNTs) and 0.348 mg/cm2 MXene only, providing functional range (0-80.7%), high sensitivity (up to 1265.18), and excellent stability and durability (stable sensing under 2300 fatigue tests, viable to the initial resistance), endurably cycled under large strains with serious damage to the conductive network. Finally, the MXene/CNTs/TPU/PSF film sensor is usable for monitoring pulse, swallow, tiptoe, and various joint bends in real time and distributing effective electrical signals. This paper implies that the MXene/CNTs/TPU/PSF film sensor has broad prospects in pragmatic applications.
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Affiliation(s)
- Xiaoyu Cui
- School of Materials Science and Engineering, Shenyang University of Aeronautics and Astronautics, Shenyang 110136, China
| | - Chengjing Miao
- School of Materials Science and Engineering, Shenyang University of Aeronautics and Astronautics, Shenyang 110136, China
| | - Shaowei Lu
- School of Materials Science and Engineering, Shenyang University of Aeronautics and Astronautics, Shenyang 110136, China
| | - Xingmin Liu
- School of Materials Science and Engineering, Shenyang University of Aeronautics and Astronautics, Shenyang 110136, China
| | - Yuxuan Yang
- School of Materials Science and Engineering, Shenyang University of Aeronautics and Astronautics, Shenyang 110136, China
| | - Jingchao Sun
- School of Science, Shenyang Aerospace University, Shenyang 110136, China
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Sannino A, Velarte A, Otín A, Artigas JI, Oliván-Viguera A. A Flexible PDMS-Based Optical Biosensor for Stretch Monitoring in Cardiac Tissue Samples. SENSORS (BASEL, SWITZERLAND) 2023; 23:9454. [PMID: 38067829 PMCID: PMC10708643 DOI: 10.3390/s23239454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 11/17/2023] [Accepted: 11/23/2023] [Indexed: 12/18/2023]
Abstract
Cardiotoxicity, characterized by adverse impacts on normal heart function due to drug exposure, is a significant concern due to the potentially serious side effects associated with various pharmaceuticals. It is essential to detect the cardiotoxicity of a drug as early as possible in the testing phase of a medical composite. Therefore, there is a pressing need for more reliable in vitro models that accurately mimic the in vivo conditions of cardiac biopsies. In a functional beating heart, cardiac muscle cells are under the effect of static and cyclic stretches. It has been demonstrated that cultured cardiac biopsies can benefit from external mechanical loads that resemble the in vivo condition, increasing the probability of cardiotoxicity detection in the early testing stages. In this work, a biosensor is designed and fabricated to allow for stretch monitoring in biopsies and tissue cultures using an innovative sensing mechanism. The detection setup is based on a biocompatible, thin, flexible membrane-where the samples are attached-which is used as an optical waveguide to detect pressure-caused shape changes and stretches. Various prototypes have been fabricated with a cost-effective process, and different measurements have been carried out to experimentally validate the proposed measurement technique. From these evaluations, stretches of up to 1.5% have been measured, but the performed simulations point towards the possibility of expanding the considered technique up to 10-30% stretches.
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Affiliation(s)
- Andrea Sannino
- Group of Power Electronics and Microelectronics, Aragon Institute for Engineering Research, University of Zaragoza, 50018 Zaragoza, Spain; (A.O.); (J.I.A.)
| | - Antonio Velarte
- Biomedical Signal Interpretation and Computational Simulation Group, Aragon Institute for Engineering Research, Aragon Health Research Institute, University of Zaragoza, 50018 Zaragoza, Spain;
| | - Aránzazu Otín
- Group of Power Electronics and Microelectronics, Aragon Institute for Engineering Research, University of Zaragoza, 50018 Zaragoza, Spain; (A.O.); (J.I.A.)
| | - José Ignacio Artigas
- Group of Power Electronics and Microelectronics, Aragon Institute for Engineering Research, University of Zaragoza, 50018 Zaragoza, Spain; (A.O.); (J.I.A.)
| | - Aida Oliván-Viguera
- CIBER-BBN, Biomedical Signal Interpretation and Computational Simulation Group, Aragon Institute for Engineering Research, Aragon Health Research Institute, University of Zaragoza, 50018 Zaragoza, Spain;
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11
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Zulkifli NA, Moon GD, Hyun DC, Lee S. Comprehensive constitutive modeling and analysis of multi-elastic polydimethylsiloxane (PDMS) for wearable device simulations. Sci Rep 2023; 13:18413. [PMID: 37891367 PMCID: PMC10611765 DOI: 10.1038/s41598-023-45372-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 10/18/2023] [Indexed: 10/29/2023] Open
Abstract
Within the field of wearable devices, polydimethylsiloxane (PDMS) has long been one of the most prominent materials utilized. It is therefore unsurprising that demands for its usage has now extended beyond experimental works into computational simulations, particularly those involving finite element method (FEM). To replicate the mechanical properties of PDMS in FEM, an accurate constitutive model is required, preferably one that encompasses wide ranges of PDMS elasticity. In this study, we determine Mooney-Rivlin 5 parameters as the best hyperelastic model fitted against PDMS experimental data, and proceed to construct a parameter correlation plot combining PDMS of different elasticities together. Experimental validation using PDMS samples fabricated via 3D-printed molds is then performed using parameters extracted from this plot, showing good agreement between simulation and experimental result. In addition, to reflect model applicability, simulations related to basic mechanical deformations involved in flexible devices (compression, stretching, bending and twisting) are performed and analyzed. Further analysis is also performed to investigate the effect of combining different experimental datasets as input into the model. We expect our work to be potentially helpful to be applied as both framework and database for wearable device engineers and researchers who are experimenting with varying PDMS concentrations and modulus.
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Affiliation(s)
- Nora Asyikin Zulkifli
- Department of Physics and Chemistry, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Dalseong-Gun, Daegu, 42988, Republic of Korea
| | - Geon Dae Moon
- Dongnam Division, Korea Institute of Industrial Technology, Busan, 46938, Republic of Korea
| | - Dong Choon Hyun
- Department of Polymer Science and Engineering, Kyungpook National University (KNU), Daegu, 41566, Republic of Korea
| | - Sungwon Lee
- Department of Physics and Chemistry, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Dalseong-Gun, Daegu, 42988, Republic of Korea.
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12
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Zhao W, Chen H, Wang Y, Zhuo Q, Liu Y, Li Y, Dong H, Li S, Tan L, Tan J, Liu Z, Li Y. Preparation of Elastic Macroporous Graphene Aerogel Based on Pickering Emulsion Method and Combination with ETPU for High Performance Piezoresistive Sensors. MICROMACHINES 2023; 14:1904. [PMID: 37893341 PMCID: PMC10609432 DOI: 10.3390/mi14101904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 10/01/2023] [Accepted: 10/02/2023] [Indexed: 10/29/2023]
Abstract
High-performance pressure sensors provide the necessary conditions for smart shoe applications. In this paper, the elastic Macroporous Graphene Aerogel (MGA) was synthesized via the modified Hummers' method, and it was further combined with Expanded-Thermoplastic polyurethane (ETPU) particles to assemble MGA-ETPU flexible sensors. The MGA-ETPU has a low apparent density (3.02 mg/cm3), high conductivity (0.024 S/cm) and fast response time (50 ms). The MGA-ETPU has a large linear sensing range (0-10 kPa) and consists of two linear regions: the low-pressure region (0 to 8 kPa) and the high-pressure region (8 to 10 kPa), with sensitivities of 0.08 kPa-1, and 0.246 kPa-1, respectively. Mechanical test results show that the MGA-ETPU sensor showed 19% reduction in maximum stress after 400 loading-unloading compression cycles at 40% strain. Electrical performance tests showed that the resistance of MGA-ETPU sensor decreased by 12.5% when subjected to sudden compression at 82% strain and returned to its original state within 0.05 s. Compared to existing flexible sensors, the MGA-ETPU sensors offer excellent performance and several distinct advantages, including ease of fabrication, high sensitivity, fast response time, and good flexibility. These remarkable features make them ideally suited as flexible pressure sensors for smart shoes.
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Affiliation(s)
- Wei Zhao
- Key Laboratory of Green Manufacturing of Super-Light Elastomer Materials of State Ethnic Affairs Commission, Hubei Minzu University, Enshi 445000, China; (W.Z.); (Y.W.); (Q.Z.); (Y.L.); (H.D.); (S.L.); (L.T.); (J.T.); (Z.L.)
- College of Intelligent Systems Science and Engineering, Hubei Minzu University, Enshi 445000, China;
| | - Hao Chen
- College of Intelligent Systems Science and Engineering, Hubei Minzu University, Enshi 445000, China;
| | - Yuqi Wang
- Key Laboratory of Green Manufacturing of Super-Light Elastomer Materials of State Ethnic Affairs Commission, Hubei Minzu University, Enshi 445000, China; (W.Z.); (Y.W.); (Q.Z.); (Y.L.); (H.D.); (S.L.); (L.T.); (J.T.); (Z.L.)
- College of Intelligent Systems Science and Engineering, Hubei Minzu University, Enshi 445000, China;
| | - Qing Zhuo
- Key Laboratory of Green Manufacturing of Super-Light Elastomer Materials of State Ethnic Affairs Commission, Hubei Minzu University, Enshi 445000, China; (W.Z.); (Y.W.); (Q.Z.); (Y.L.); (H.D.); (S.L.); (L.T.); (J.T.); (Z.L.)
- College of Intelligent Systems Science and Engineering, Hubei Minzu University, Enshi 445000, China;
| | - Yaopeng Liu
- College of Chemical and Environmental Engineering, Hubei Minzu University, Enshi 445000, China;
| | - Yuanyuan Li
- Key Laboratory of Green Manufacturing of Super-Light Elastomer Materials of State Ethnic Affairs Commission, Hubei Minzu University, Enshi 445000, China; (W.Z.); (Y.W.); (Q.Z.); (Y.L.); (H.D.); (S.L.); (L.T.); (J.T.); (Z.L.)
- College of Intelligent Systems Science and Engineering, Hubei Minzu University, Enshi 445000, China;
| | - Hangyu Dong
- Key Laboratory of Green Manufacturing of Super-Light Elastomer Materials of State Ethnic Affairs Commission, Hubei Minzu University, Enshi 445000, China; (W.Z.); (Y.W.); (Q.Z.); (Y.L.); (H.D.); (S.L.); (L.T.); (J.T.); (Z.L.)
- College of Intelligent Systems Science and Engineering, Hubei Minzu University, Enshi 445000, China;
| | - Shidong Li
- Key Laboratory of Green Manufacturing of Super-Light Elastomer Materials of State Ethnic Affairs Commission, Hubei Minzu University, Enshi 445000, China; (W.Z.); (Y.W.); (Q.Z.); (Y.L.); (H.D.); (S.L.); (L.T.); (J.T.); (Z.L.)
- College of Intelligent Systems Science and Engineering, Hubei Minzu University, Enshi 445000, China;
| | - Linli Tan
- Key Laboratory of Green Manufacturing of Super-Light Elastomer Materials of State Ethnic Affairs Commission, Hubei Minzu University, Enshi 445000, China; (W.Z.); (Y.W.); (Q.Z.); (Y.L.); (H.D.); (S.L.); (L.T.); (J.T.); (Z.L.)
- College of Intelligent Systems Science and Engineering, Hubei Minzu University, Enshi 445000, China;
| | - Jianfeng Tan
- Key Laboratory of Green Manufacturing of Super-Light Elastomer Materials of State Ethnic Affairs Commission, Hubei Minzu University, Enshi 445000, China; (W.Z.); (Y.W.); (Q.Z.); (Y.L.); (H.D.); (S.L.); (L.T.); (J.T.); (Z.L.)
- College of Intelligent Systems Science and Engineering, Hubei Minzu University, Enshi 445000, China;
| | - Zhuo Liu
- Key Laboratory of Green Manufacturing of Super-Light Elastomer Materials of State Ethnic Affairs Commission, Hubei Minzu University, Enshi 445000, China; (W.Z.); (Y.W.); (Q.Z.); (Y.L.); (H.D.); (S.L.); (L.T.); (J.T.); (Z.L.)
- College of Intelligent Systems Science and Engineering, Hubei Minzu University, Enshi 445000, China;
| | - Yingru Li
- Key Laboratory of Green Manufacturing of Super-Light Elastomer Materials of State Ethnic Affairs Commission, Hubei Minzu University, Enshi 445000, China; (W.Z.); (Y.W.); (Q.Z.); (Y.L.); (H.D.); (S.L.); (L.T.); (J.T.); (Z.L.)
- College of Intelligent Systems Science and Engineering, Hubei Minzu University, Enshi 445000, China;
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13
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Zhang C, Wu M, Cao S, Liu M, Guo D, Kang Z, Li M, Ye D, Yang Z, Wang X, Xie Z, Liu J. Bioinspired Environment-Adaptable and Ultrasensitive Multifunctional Electronic Skin for Human Healthcare and Robotic Sensations. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2304004. [PMID: 37300351 DOI: 10.1002/smll.202304004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Indexed: 06/12/2023]
Abstract
Multifunctional electronic skins (e-skins) that can sense various stimuli have demonstrated increasing potential in many fields. However, most e-skins are human-oriented that cannot work in hash environments such as high temperature, underwater, and corrosive chemicals, impairing their applications, especially in human-machine interfaces, intelligent machines, robotics, and so on. Inspired by the crack-shaped sensory organs of spiders, an environmentally robust and ultrasensitive multifunctional e-skin is developed. By developing a polyimide-based metal crack-localization strategy, the device has excellent environment adaptability since polyimide has high thermal stability and chemical durability. The localized cracked part serves as an ultrasensitive strain sensing unit, while the non-cracked serpentine part is solely responsible for temperature. Since the two units are made of the same material and process, the signals are decoupled easily. The proposed device is the first multifunctional e-skin that can be used in harsh environments, therefore is of great potential for both human and robot-oriented applications.
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Affiliation(s)
- Chi Zhang
- State Key Laboratory of High-performance Precision Manufacturing, Dalian University of Technology, Dalian, Liaoning, 116024, China
| | - Mengxi Wu
- State Key Laboratory of High-performance Precision Manufacturing, Dalian University of Technology, Dalian, Liaoning, 116024, China
| | - Shuye Cao
- State Key Laboratory of High-performance Precision Manufacturing, Dalian University of Technology, Dalian, Liaoning, 116024, China
| | - Mengjing Liu
- State Key Laboratory of High-performance Precision Manufacturing, Dalian University of Technology, Dalian, Liaoning, 116024, China
| | - Di Guo
- State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian, 116024, China
| | - Zhan Kang
- State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian, 116024, China
| | - Ming Li
- State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian, 116024, China
| | - Dong Ye
- State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Zhuoqing Yang
- National Key Laboratory of Science and Technology on Micro and Nano Fabrication, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xuewen Wang
- Institute of Flexible Electronics, Northwestern Polytechnical University, Xi'an, 710072, China
| | - Zhaoqian Xie
- Department of Engineering Mechanics, Dalian University of Technology, Dalian, 116024, China
| | - Junshan Liu
- State Key Laboratory of High-performance Precision Manufacturing, Dalian University of Technology, Dalian, Liaoning, 116024, China
- Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, Dalian, Liaoning, 116024, China
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14
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Zhao N, Zhang H, Yang S, Sun Y, Zhao G, Fan W, Yan Z, Lin J, Wan C. Direct Induction of Porous Graphene from Mechanically Strong and Waterproof Biopaper for On-Chip Multifunctional Flexible Electronics. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2300242. [PMID: 37381614 DOI: 10.1002/smll.202300242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 06/05/2023] [Indexed: 06/30/2023]
Abstract
Graphene with a 3D porous structure is directly laser-induced on lignocellulosic biopaper under ambient conditions and is further explored for multifunctional biomass-based flexible electronics. The mechanically strong, flexible, and waterproof biopaper is fabricated by surface-functionalizing cellulose with lignin-based epoxy acrylate (LBEA). This composite biopaper shows as high as a threefold increase in tensile strength and excellent waterproofing compared with pure cellulose one. Direct laser writing (DLW) rapidly induces porous graphene from the biopaper in a single step. The porous graphene shows an interconnected carbon network, well-defined graphene domains, and high electrical conductivity (e.g., ≈3 Ω per square), which can be tuned by lignin precursors and loadings as well as lasing conditions. The biopaper in situ embedded with porous graphene is facilely fabricated into flexible electronics for on-chip and paper-based applications. The biopaper-based electronic devices, including the all-solid-state planer supercapacitor, electrochemical and strain biosensors, and Joule heater, show great performances. This study demonstrates the facile, versatile, and low-cost fabrication of multifunctional graphene-based electronics from lignocellulose-based biopaper.
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Affiliation(s)
- Nan Zhao
- Department of Chemical and Biomedical Engineering, University of Missouri, 1406 East Rollins Street, Columbia, MO, 65211, USA
- School of Ecology and Environment, Zhengzhou University, 100 Kexue Blvd, Zhengzhou, Henan Province, 450001, China
| | - Hanwen Zhang
- Department of Chemical and Biomedical Engineering, University of Missouri, 1406 East Rollins Street, Columbia, MO, 65211, USA
| | - Shuhong Yang
- Department of Chemical and Biomedical Engineering, University of Missouri, 1406 East Rollins Street, Columbia, MO, 65211, USA
| | - Yisheng Sun
- Department of Chemical and Biomedical Engineering, University of Missouri, 1406 East Rollins Street, Columbia, MO, 65211, USA
| | - Ganggang Zhao
- Department of Mechanical and Aerospace Engineering, University of Missouri, 416 South 6th Street, Columbia, MO, 65211, USA
| | - Wenjun Fan
- Department of Chemical and Biomedical Engineering, University of Missouri, 1406 East Rollins Street, Columbia, MO, 65211, USA
| | - Zheng Yan
- Department of Chemical and Biomedical Engineering, University of Missouri, 1406 East Rollins Street, Columbia, MO, 65211, USA
- Department of Mechanical and Aerospace Engineering, University of Missouri, 416 South 6th Street, Columbia, MO, 65211, USA
| | - Jian Lin
- Department of Mechanical and Aerospace Engineering, University of Missouri, 416 South 6th Street, Columbia, MO, 65211, USA
| | - Caixia Wan
- Department of Chemical and Biomedical Engineering, University of Missouri, 1406 East Rollins Street, Columbia, MO, 65211, USA
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15
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Velarte A, Otin A, Giménez-Gómez P, Muñoz-Berbel X, Pueyo E. Fiber-Optic-Based System for High-Resolution Monitoring of Stretch in Excised Tissues. BIOSENSORS 2023; 13:900. [PMID: 37887093 PMCID: PMC10605064 DOI: 10.3390/bios13100900] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 08/22/2023] [Accepted: 08/25/2023] [Indexed: 10/28/2023]
Abstract
Cardiovascular diseases cause a high number of deaths nowadays. To improve these statistics, new strategies to better understand the electrical and mechanical abnormalities underlying them are urgently required. This study focuses on the development of a sensor to measure tissue stretch in excised tissues, enabling improved knowledge of biomechanical properties and allowing greater control in real time. A system made of biocompatible materials is described, which is based on two cantilevered platforms that integrate an optical fiber inside them to quantify the amount of stretch the tissues are exposed to with a precision of μm. The operating principle of the sensor is based on the variation of the optical path with the movement of the platforms onto which the samples are fixed. The conducted tests highlight that this system, based on a simple topology and technology, is capable of achieving the desired purpose (a resolution of ∼1 μm), enabling the tissue to be bathed in any medium within the system.
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Affiliation(s)
- Antonio Velarte
- Biomedical Signal Interpretation and Computational Simulation (BSICoS) Group, I3A Institute, IIS Aragón, University of Zaragoza, 50018 Zaragoza, Spain;
| | - Aranzazu Otin
- Grupo de Electrónica de Potencia y Microelectrónica (GEPM) Group, I3A Institute, University of Zaragoza, 50018 Zaragoza, Spain;
| | - Pablo Giménez-Gómez
- Department of Materials and Environmental Chemistry, Stockholm University, 106 91 Stockholm, Sweden;
| | - Xavier Muñoz-Berbel
- Instituto de Microelectrónica de Barcelona (IMB-CNM), Consejo Superior de Investigaciones Científicas (CSIC), Campus UAB, 08193 Cerdanyola del Vallès, Spain;
- Centro de Investigación Biomédica en Red (CIBER) de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid, Spain
| | - Esther Pueyo
- Biomedical Signal Interpretation and Computational Simulation (BSICoS) Group, I3A Institute, IIS Aragón, University of Zaragoza, 50018 Zaragoza, Spain;
- Centro de Investigación Biomédica en Red (CIBER) de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid, Spain
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16
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Wu SD, Hsu SH, Ketelsen B, Bittinger SC, Schlicke H, Weller H, Vossmeyer T. Fabrication of Eco-Friendly Wearable Strain Sensor Arrays via Facile Contact Printing for Healthcare Applications. SMALL METHODS 2023; 7:e2300170. [PMID: 37154264 DOI: 10.1002/smtd.202300170] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/28/2023] [Indexed: 05/10/2023]
Abstract
Wearable flexible strain sensors with spatial resolution enable the acquisition and analysis of complex actions for noninvasive personalized healthcare applications. To provide secure contact with skin and to avoid environmental pollution after usage, sensors with biocompatibility and biodegradability are highly desirable. Herein, wearable flexible strain sensors composed of crosslinked gold nanoparticle (GNP) thin films as the active conductive layer and transparent biodegradable polyurethane (PU) films as the flexible substrate are developed. The patterned GNP films (micrometer- to millimeter-scale square and rectangle geometry, alphabetic characters, and wave and array patterns) are transferred onto the biodegradable PU film via a facile, clean, rapid and high-precision contact printing method, without the need of a sacrificial polymer carrier or organic solvents. The GNP-PU strain sensor with low Young's modulus (≈17.8 MPa) and high stretchability showed good stability and durability (10 000 cycles) as well as degradability (42% weight loss after 17 days at 74 °C in water). The GNP-PU strain sensor arrays with spatiotemporal strain resolution are applied as wearable eco-friendly electronics for monitoring subtle physiological signals (e.g., mapping of arterial lines and sensing pulse waveforms) and large-strain actions (e.g., finger bending).
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Affiliation(s)
- Shin-Da Wu
- Institute of Polymer Science and Engineering, National Taiwan University, Taipei, 10617, Taiwan
- Institute of Physical Chemistry, University of Hamburg, 20146, Hamburg, Germany
| | - Shan-Hui Hsu
- Institute of Polymer Science and Engineering, National Taiwan University, Taipei, 10617, Taiwan
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli, 35053, Taiwan
| | - Bendix Ketelsen
- Institute of Physical Chemistry, University of Hamburg, 20146, Hamburg, Germany
| | - Sophia C Bittinger
- Institute of Physical Chemistry, University of Hamburg, 20146, Hamburg, Germany
| | - Hendrik Schlicke
- Fraunhofer Center for Applied Nanotechnology CAN, 20146, Hamburg, Germany
| | - Horst Weller
- Institute of Physical Chemistry, University of Hamburg, 20146, Hamburg, Germany
- Fraunhofer Center for Applied Nanotechnology CAN, 20146, Hamburg, Germany
| | - Tobias Vossmeyer
- Institute of Physical Chemistry, University of Hamburg, 20146, Hamburg, Germany
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17
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Won D, Bang J, Choi SH, Pyun KR, Jeong S, Lee Y, Ko SH. Transparent Electronics for Wearable Electronics Application. Chem Rev 2023; 123:9982-10078. [PMID: 37542724 PMCID: PMC10452793 DOI: 10.1021/acs.chemrev.3c00139] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Indexed: 08/07/2023]
Abstract
Recent advancements in wearable electronics offer seamless integration with the human body for extracting various biophysical and biochemical information for real-time health monitoring, clinical diagnostics, and augmented reality. Enormous efforts have been dedicated to imparting stretchability/flexibility and softness to electronic devices through materials science and structural modifications that enable stable and comfortable integration of these devices with the curvilinear and soft human body. However, the optical properties of these devices are still in the early stages of consideration. By incorporating transparency, visual information from interfacing biological systems can be preserved and utilized for comprehensive clinical diagnosis with image analysis techniques. Additionally, transparency provides optical imperceptibility, alleviating reluctance to wear the device on exposed skin. This review discusses the recent advancement of transparent wearable electronics in a comprehensive way that includes materials, processing, devices, and applications. Materials for transparent wearable electronics are discussed regarding their characteristics, synthesis, and engineering strategies for property enhancements. We also examine bridging techniques for stable integration with the soft human body. Building blocks for wearable electronic systems, including sensors, energy devices, actuators, and displays, are discussed with their mechanisms and performances. Lastly, we summarize the potential applications and conclude with the remaining challenges and prospects.
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Affiliation(s)
- Daeyeon Won
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Junhyuk Bang
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Seok Hwan Choi
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Kyung Rok Pyun
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Seongmin Jeong
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Youngseok Lee
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Seung Hwan Ko
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
- Institute
of Engineering Research/Institute of Advanced Machinery and Design
(SNU-IAMD), Seoul National University, Seoul 08826, South Korea
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18
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Gao Y, Zhang H, Song B, Zhao C, Lu Q. Electric Double Layer Based Epidermal Electronics for Healthcare and Human-Machine Interface. BIOSENSORS 2023; 13:787. [PMID: 37622873 PMCID: PMC10452760 DOI: 10.3390/bios13080787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/25/2023] [Accepted: 07/31/2023] [Indexed: 08/26/2023]
Abstract
Epidermal electronics, an emerging interdisciplinary field, is advancing the development of flexible devices that can seamlessly integrate with the skin. These devices, especially Electric Double Layer (EDL)-based sensors, overcome the limitations of conventional electronic devices, offering high sensitivity, rapid response, and excellent stability. Especially, Electric Double Layer (EDL)-based epidermal sensors show great potential in the application of wearable electronics to detect biological signals due to their high sensitivity, fast response, and excellent stability. The advantages can be attributed to the biocompatibility of the materials, the flexibility of the devices, and the large capacitance due to the EDL effect. Furthermore, we discuss the potential of EDL epidermal electronics as wearable sensors for health monitoring and wound healing. These devices can analyze various biofluids, offering real-time feedback on parameters like pH, temperature, glucose, lactate, and oxygen levels, which aids in accurate diagnosis and effective treatment. Beyond healthcare, we explore the role of EDL epidermal electronics in human-machine interaction, particularly their application in prosthetics and pressure-sensing robots. By mimicking the flexibility and sensitivity of human skin, these devices enhance the functionality and user experience of these systems. This review summarizes the latest advancements in EDL-based epidermal electronic devices, offering a perspective for future research in this rapidly evolving field.
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Affiliation(s)
- Yuan Gao
- School of CHIPS, XJTLU Entrepreneur College (Taicang), Xi’an Jiaotong-Liverpool University, 111 Taicang Avenue, Taicang 215488, China; (Y.G.); (H.Z.); (B.S.)
| | - Hanchu Zhang
- School of CHIPS, XJTLU Entrepreneur College (Taicang), Xi’an Jiaotong-Liverpool University, 111 Taicang Avenue, Taicang 215488, China; (Y.G.); (H.Z.); (B.S.)
| | - Bowen Song
- School of CHIPS, XJTLU Entrepreneur College (Taicang), Xi’an Jiaotong-Liverpool University, 111 Taicang Avenue, Taicang 215488, China; (Y.G.); (H.Z.); (B.S.)
| | - Chun Zhao
- School of Advanced Technology, Xi’an Jiaotong-Liverpool University, Suzhou 215123, China;
| | - Qifeng Lu
- School of CHIPS, XJTLU Entrepreneur College (Taicang), Xi’an Jiaotong-Liverpool University, 111 Taicang Avenue, Taicang 215488, China; (Y.G.); (H.Z.); (B.S.)
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19
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Zhang X, Li N, Wang G, Zhang C, Zhang Y, Zeng F, Liu H, Yi G, Wang Z. Research status of polysiloxane-based piezoresistive flexible human electronic sensors. RSC Adv 2023; 13:16693-16711. [PMID: 37274402 PMCID: PMC10236448 DOI: 10.1039/d3ra03258b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 05/21/2023] [Indexed: 06/06/2023] Open
Abstract
Flexible human body electronic sensor is a multifunctional electronic device with flexibility, extensibility, and responsiveness. Piezoresistive flexible human body electronic sensor has attracted the extensive attention of researchers because of its simple preparation process, high detection sensitivity, wide detection range, and low power consumption. However, the wearability and affinity to the human body of traditional flexible human electronic sensors are poor, while polysiloxane materials can be mixed with other electronic materials and have good affinity toward the human body. Therefore, polysiloxane materials have become the first choice of flexible matrixes. In this study, the research progress and preparation methods of piezoresistive flexible human electronic sensors based on polysiloxane materials in recent years are summarized, the challenges faced in the development of piezoresistive flexible human electronic sensors are analyzed, and the future research directions are prospected.
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Affiliation(s)
- Xiaoyu Zhang
- Jiangsu Collaborative Innovation Center for Photovoltaic Science and Engineering, Jiangsu Province Cultivation Base for State Key Laboratory of Photovoltaic Science and Technology, Jiangsu Province Key Laboratory of Environmentally Friendly Polymer Materials, School of Materials Science and Engineering, Changzhou University Changzhou 213164 China
| | - Ning Li
- Jiangsu Collaborative Innovation Center for Photovoltaic Science and Engineering, Jiangsu Province Cultivation Base for State Key Laboratory of Photovoltaic Science and Technology, Jiangsu Province Key Laboratory of Environmentally Friendly Polymer Materials, School of Materials Science and Engineering, Changzhou University Changzhou 213164 China
| | - Guorui Wang
- Jiangsu Collaborative Innovation Center for Photovoltaic Science and Engineering, Jiangsu Province Cultivation Base for State Key Laboratory of Photovoltaic Science and Technology, Jiangsu Province Key Laboratory of Environmentally Friendly Polymer Materials, School of Materials Science and Engineering, Changzhou University Changzhou 213164 China
| | - Chi Zhang
- Jiangsu Collaborative Innovation Center for Photovoltaic Science and Engineering, Jiangsu Province Cultivation Base for State Key Laboratory of Photovoltaic Science and Technology, Jiangsu Province Key Laboratory of Environmentally Friendly Polymer Materials, School of Materials Science and Engineering, Changzhou University Changzhou 213164 China
| | - Yu Zhang
- Jiangsu Collaborative Innovation Center for Photovoltaic Science and Engineering, Jiangsu Province Cultivation Base for State Key Laboratory of Photovoltaic Science and Technology, Jiangsu Province Key Laboratory of Environmentally Friendly Polymer Materials, School of Materials Science and Engineering, Changzhou University Changzhou 213164 China
| | - Fanglei Zeng
- Jiangsu Collaborative Innovation Center for Photovoltaic Science and Engineering, Jiangsu Province Cultivation Base for State Key Laboratory of Photovoltaic Science and Technology, Jiangsu Province Key Laboratory of Environmentally Friendly Polymer Materials, School of Materials Science and Engineering, Changzhou University Changzhou 213164 China
| | - Hailong Liu
- Shandong Dongyue Silicone Material Co. ,Ltd. Zibo 256401 China
| | - Gang Yi
- Shandong Dongyue Silicone Material Co. ,Ltd. Zibo 256401 China
| | - Zhongwei Wang
- College of Materials Science and Engineering, Shandong University of Science and Technology Qingdao 266590 China
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20
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Haridas A, Sharma S, Naskar K, Mondal T. Cross-Talk Signal Free Recyclable Thermoplastic Polyurethane/Graphene-Based Strain and Pressure Sensor for Monitoring Human Motions. ACS APPLIED MATERIALS & INTERFACES 2023; 15:17279-17292. [PMID: 36944054 DOI: 10.1021/acsami.3c01364] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Developing a sensor that can read out cross-talk free signals while determining various active physiological parameters is demanding in the field of point-of-care applications. While there are a few examples of non-flexible sensors available, the management of electronic waste generated from such sensors is critical. Most of such available sensors are rigid in form factor and hence limit their usability in healthcare monitoring due to their poor conformity to human skin. Combining these facets, studies on the development of a recyclable cross-talk free flexible sensor for monitoring human motions and active parameters are far and few. In this work, we report on the development of a recyclable flexible sensor that can provide accurate data for detecting small changes in strain as well as pressure. The developed sensor could decipher the signals individually responsible due to strain as well as pressure. Hence, it can deliver a cross-talk free output. Thermoplastic polyurethane and graphene were selected as the model system. The thermoplastic polyurethane/graphene sensor exhibited a tensile strain sensitivity of GF ≃ 3.375 for 0-100% strain and 10.551 for 100-150% strain and a pressure sensitivity of ∼-0.25 kPa-1. We demonstrate the applicability of the strain sensor for monitoring a variety of human motions ranging from a very small strain of eye blinking to a large strain of elbow bending with unambiguous peaks and a very fast response and recovery time of 165 ms. The signals received are mostly electrical hysteresis free. To confirm the recyclability, the developed sensor was recycled up to three times. Marginal decrement in the sensitivity was noted with recycling without compromising the sensing capabilities. These findings promise to open up a new avenue for developing flexible sensors with lesser carbon footprints.
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Affiliation(s)
- Ajay Haridas
- Rubber Technology Centre, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Simran Sharma
- Rubber Technology Centre, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Kinsuk Naskar
- Rubber Technology Centre, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Titash Mondal
- Rubber Technology Centre, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
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21
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Muhammad W, Kim SD. Highly Stretchable PPy/PDMS Strain Sensors Fabricated with Multi-Step Oxygen Plasma Treatment. Polymers (Basel) 2023; 15:polym15071714. [PMID: 37050328 PMCID: PMC10096996 DOI: 10.3390/polym15071714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 03/27/2023] [Accepted: 03/27/2023] [Indexed: 04/14/2023] Open
Abstract
We present highly stretchable polypyrrole (PPy)/polydimethylsiloxane strain sensors of highly improved sensitivity and durability fabricated by a chemical oxidative polymerization with oxygen plasma treatment (O2 PT). In this study, O2 PT was performed for 30, 60, and 90 s at each growth stage of the PPy film in three steps to investigate the effects on the sensor performance as well as the microstructural properties of the PPy films. Bonding characteristics with underlying layers and resistance to microcrack generation of the multi-layer PPy films under our given strained state were significantly enhanced by the O2 PT. The best sensor performance in terms of sensitivity and stability were achieved by PT for 30 s with a maximum gauge factor of ~438 at a uniaxial strain of 50%, excellent durability over 500 stretching/release cycles, and a fast response time of ~50 ms.
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Affiliation(s)
- Waqar Muhammad
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 100-175, Republic of Korea
| | - Sam-Dong Kim
- Division of Electronics and Electrical Engineering, Dongguk University, Seoul 100-175, Republic of Korea
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22
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Optimal Design of Carbon-Based Polymer Nanocomposites Preparation Based on Response Surface Methodology. Polymers (Basel) 2023; 15:polym15061494. [PMID: 36987274 PMCID: PMC10052088 DOI: 10.3390/polym15061494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 03/19/2023] Open
Abstract
Response surface methodology (RSM) and central composite design (CCD) were used to improve the preparation of carbon nanotube and graphene (CNT-GN)-sensing unit composite materials in this study. Four independent variable factors (CNT content, GN content, mixing time, and curing temperature) were controlled at five levels, and 30 samples were generated using the multivariate control analysis technique. On the basis of the experimental design, semi-empirical equations were developed and utilized to predict the sensitivity and compression modulus of the generated samples. The results reveal a strong correlation between the experimental and expected values of sensitivity and the compression modulus for the CNT-GN/RTV (room-temperature-vulcanized silicone rubber) polymer nanocomposites fabricated using different design strategies. The correlation coefficients for the sensitivity and compression modulus are R2 =0.9634 and R2=0.9115, respectively. The ideal preparation parameters of the composite in the experimental range include a CNT content of 1.1 g, a GN content of 1.0 g, a mixing time of 15 min, and a curing temperature of 68.6 °C, according to theoretical predictions and experimental findings. At 0~30 kPa, the CNT-GN/RTV-sensing unit composite materials may reach a sensitivity of 0.385 kPa−1 and a compressive modulus of 601.567 kPa. This provides a new idea for the preparation of flexible sensor cells and reduces the time and economic cost of experiments.
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23
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Tuli A, Singh AP. Polymer-based wearable nano-composite sensors: a review. INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION 2023. [DOI: 10.1080/1023666x.2022.2161737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Aashish Tuli
- Mechanical Engineering, UIET Panjab University, Chandigarh, India
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Simegnaw AA, Teyeme Y, Malengier B, Tesfaye T, Daba H, Esmelealem K, Langenhove LV. Smart Shirt for Measuring Trunk Orientation. SENSORS (BASEL, SWITZERLAND) 2022; 22:9090. [PMID: 36501789 PMCID: PMC9739249 DOI: 10.3390/s22239090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/02/2022] [Accepted: 11/10/2022] [Indexed: 06/17/2023]
Abstract
Improper cycling posture is linked to a variety of spinal musculoskeletal diseases, including structural malformation of the spine and back discomfort. This paper presents a novel smart shirt integrated tri-axial gyroscope and accelerometer that can detect postural variation in terms of spinal curvature changes. To provide accurate feedback to the wearer and improve the wearer's correct movement, the garment is able to recognize trunk body posture. The gyroscope/accelerometer was placed around the upper and mid trunk of the user to record tri-axial angular velocity data. The device can also be used to help determine the trunk bending angle and monitor body postures in order to improve optimal orientation and position. The garment enables continuous measurement in the field at high sample rates (50 Hz), and the sensor has a large measurement range (16 g, 2000°/s). As electronic components are non-washable, instead of encapsulating them, a detachable module was created. In this, magnets are embedded in the jersey, and allow the positioning and removal of the sensor. The test results show that the average trunk-bending angle was 21.5°, and 99 percent of the observed angle fell within the standard (ranging from 8° to 35°). The findings demonstrate the feasibility of employing the smart shirt sensor to estimate trunk motions in the field on a regular basis.
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Affiliation(s)
- Abdella Ahmmed Simegnaw
- Centre for Textile Science, Engineering Department of Materials, Textiles and Chemical Engineering, Ghent University, 9000 Gent, Belgium
- Ethiopian Institute of Textile and Fashion Technology, Bahir Dar University, P.O. Box 1037, Bahir Dar 6000, Ethiopia
| | - Yetanawork Teyeme
- Centre for Textile Science, Engineering Department of Materials, Textiles and Chemical Engineering, Ghent University, 9000 Gent, Belgium
- Ethiopian Institute of Textile and Fashion Technology, Bahir Dar University, P.O. Box 1037, Bahir Dar 6000, Ethiopia
| | - Benny Malengier
- Centre for Textile Science, Engineering Department of Materials, Textiles and Chemical Engineering, Ghent University, 9000 Gent, Belgium
| | - Tamrat Tesfaye
- Ethiopian Institute of Textile and Fashion Technology, Bahir Dar University, P.O. Box 1037, Bahir Dar 6000, Ethiopia
| | - Hundessa Daba
- Institute of Technology, School of Biomedical Engineering, Jimma University, Jimma P.O. Box 378, Ethiopia
| | - Kaledawit Esmelealem
- Bahir Dar Institute of Technology, Faculty of Computing, Computer Science, Bahir Dar University, P.O. Box 26, Bahir Dar 6000, Ethiopia
| | - Lieva Van Langenhove
- Centre for Textile Science, Engineering Department of Materials, Textiles and Chemical Engineering, Ghent University, 9000 Gent, Belgium
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25
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Yuan YH, Gu HX, Xie QY, Zhang J. In-situ SERS detection of aromatic amine pollutants in fire-fighting wastewater using low-cost flexible substrates. Microchem J 2022. [DOI: 10.1016/j.microc.2022.108139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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26
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Zamperlin N, Bottacini A, Callone E, Pegoretti A, Fontana M, Dirè S. Barium Titanate Functionalization with Organosilanes: Effect on Particle Compatibility and Permittivity in Nanocomposites. Molecules 2022; 27:molecules27196499. [PMID: 36235034 PMCID: PMC9572045 DOI: 10.3390/molecules27196499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/24/2022] [Accepted: 09/27/2022] [Indexed: 11/16/2022] Open
Abstract
Barium titanate (BT) recently gained new interest in the preparation of dielectric and piezoelectric lead-free materials for applications in sensors, electronics, energy harvesting and storage fields. Barium titanate nanocomposites can achieve attractive performance, provided that the compatibility between ceramic particles and polymeric matrices is enhanced to the benefit of the physical properties of the final composite. Tuning the particle-matrix interface through particle functionalization represents a viable solution. In this work, surface functionalization of BT nanoparticles (NPs), obtained by hydrothermal synthesis, with 3-glycidyloxypropyltrimethoxysilane, 2-[(acetoxy(polyethyleneoxy)propyl]triethoxysilane and triethoxysilylpropoxy(polyethyleneoxy)dodecanoate, was performed after optimizing the hydroxylation process of the NPs to improve their surface reactivity and increase the yield of grafting. Solid-state nuclear magnetic resonance and thermogravimetric analysis were used to quantify the molecules grafted onto the ceramic nanoparticles. Both bare and functionalized particles were employed in the realization of epoxy- and polydimethylsiloxane (PDMS)-based nanocomposites. Functionalization was proven to be beneficial for particle dispersibility and effective for particle alignment in the PDMS matrix. Moreover, the dielectric constant measurements revealed the potential of PDMS-based nanocomposites for applications in the field of dielectric elastomers.
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Affiliation(s)
- Nico Zamperlin
- Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, Italy
- Correspondence:
| | - Andrea Bottacini
- Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, Italy
| | - Emanuela Callone
- Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, Italy
| | - Alessandro Pegoretti
- Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, Italy
- National Interuniversity Consortium of Materials Science and Technology (INSTM), Via G. Giusti, 9, 50121 Firenze, Italy
| | - Marco Fontana
- Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, Italy
- Institute of Mechanical Intelligence, Scuola Superiore Sant’Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy
| | - Sandra Dirè
- Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 Trento, Italy
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27
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Hetzler Z, Wang Y, Krafft D, Jamalzadegan S, Overton L, Kudenov MW, Ligler FS, Wei Q. Flexible sensor patch for continuous carbon dioxide monitoring. Front Chem 2022; 10:983523. [PMID: 36238093 PMCID: PMC9552331 DOI: 10.3389/fchem.2022.983523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
Monitoring and measurement of carbon dioxide (CO2) is critical for many fields. The gold standard CO2 sensor, the Severinghaus electrode, has remained unchanged for decades. In recent years, many other CO2 sensor formats, such as detection based upon pH-sensitive dyes, have been demonstrated, opening the door for relatively simple optical detection schemes. However, a majority of these optochemical sensors require complex sensor preparation steps and are difficult to control and repeatably execute. Here, we report a facile CO2 sensor generation method that suffers from none of the typical fabrication issues. The method described here utilizes polydimethylsiloxane (PDMS) as the flexible sensor matrix and 1-hydroxypyrene-3,6,8-trisulfonate (HPTS), a pH-sensitive dye, as the sensing material. HPTS, a base (NaOH), and glycerol are loaded as dense droplets into a thin PDMS layer which is subsequently cured around the droplet. The fabrication process does not require prior knowledge in chemistry or device fabrication and can be completed as quickly as PDMS cures (∼2 h). We demonstrate the application of this thin-patch sensor for in-line CO2 quantification in cell culture media. To this end, we optimized the sensing composition and quantified CO2 in the range of 0–20 kPa. A standard curve was generated with high fidelity (R2 = 0.998) along with an analytical resolution of 0.5 kPa (3.7 mm Hg). Additionally, the sensor is fully autoclavable for applications requiring sterility and has a long working lifetime. This flexible, simple-to-manufacture sensor has a myriad of potential applications and represents a new, straightforward means for optical carbon dioxide measurement.
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Affiliation(s)
- Zach Hetzler
- Department of Chemical and Biomolecular Engineering, NC State University, Raleigh, NC, United States
| | - Yan Wang
- Department of Chemical and Biomolecular Engineering, NC State University, Raleigh, NC, United States
| | - Danny Krafft
- Department of Electrical and Computer Engineering, NC State University, Raleigh, NC, United States
| | - Sina Jamalzadegan
- Department of Chemical and Biomolecular Engineering, NC State University, Raleigh, NC, United States
| | - Laurie Overton
- Biomanufacturing Training and Education Center (BTEC), NC State University, Raleigh, NC, United States
| | - Michael W. Kudenov
- Department of Electrical and Computer Engineering, NC State University, Raleigh, NC, United States
| | - Frances S. Ligler
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, United States
| | - Qingshan Wei
- Department of Chemical and Biomolecular Engineering, NC State University, Raleigh, NC, United States
- *Correspondence: Qingshan Wei,
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28
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Mishra S, Mohanty S, Ramadoss A. Functionality of Flexible Pressure Sensors in Cardiovascular Health Monitoring: A Review. ACS Sens 2022; 7:2495-2520. [PMID: 36036627 DOI: 10.1021/acssensors.2c00942] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
As the highest percentage of global mortality is caused by several cardiovascular diseases (CVD), maintenance and monitoring of a healthy cardiovascular condition have become the primary concern of each and every individual. Simultaneously, recent progress and advances in wearable pressure sensor technology have provided many pathways to monitor and detect underlying cardiovascular illness in terms of irregularities in heart rate, blood pressure, and blood oxygen saturation. These pressure sensors can be comfortably attached onto human skin or can be implanted on the surface of vascular grafts for uninterrupted monitoring of arterial blood pressure. While the traditional monitoring systems are time-consuming, expensive, and not user-friendly, flexible sensor technology has emerged as a promising and dynamic practice to collect important health information at a comparatively low cost in a reliable and user-friendly way. This Review explores the importance and necessity of cardiovascular health monitoring while emphasizing the role of flexible pressure sensors in monitoring patients' health conditions to avoid adverse effects. A comprehensive discussion on the current research progress along with the real-time impact and accessibility of pressure sensors developed for cardiovascular health monitoring applications has been provided.
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Affiliation(s)
- Suvrajyoti Mishra
- School for Advanced Research in Petrochemicals: Laboratory for Advanced Research in Polymeric Materials (LARPM), Central Institute of Petrochemicals Engineering and Technology (CIPET), Bhubaneswar-751024, India
| | - Smita Mohanty
- School for Advanced Research in Petrochemicals: Laboratory for Advanced Research in Polymeric Materials (LARPM), Central Institute of Petrochemicals Engineering and Technology (CIPET), Bhubaneswar-751024, India
| | - Ananthakumar Ramadoss
- School for Advanced Research in Petrochemicals: Laboratory for Advanced Research in Polymeric Materials (LARPM), Central Institute of Petrochemicals Engineering and Technology (CIPET), Bhubaneswar-751024, India
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29
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Wearable Sensors for Healthcare: Fabrication to Application. SENSORS 2022; 22:s22145137. [PMID: 35890817 PMCID: PMC9323732 DOI: 10.3390/s22145137] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/06/2022] [Accepted: 07/06/2022] [Indexed: 02/07/2023]
Abstract
This paper presents a substantial review of the deployment of wearable sensors for healthcare applications. Wearable sensors hold a pivotal position in the microelectronics industry due to their role in monitoring physiological movements and signals. Sensors designed and developed using a wide range of fabrication techniques have been integrated with communication modules for transceiving signals. This paper highlights the entire chronology of wearable sensors in the biomedical sector, starting from their fabrication in a controlled environment to their integration with signal-conditioning circuits for application purposes. It also highlights sensing products that are currently available on the market for a comparative study of their performances. The conjugation of the sensing prototypes with the Internet of Things (IoT) for forming fully functioning sensorized systems is also shown here. Finally, some of the challenges existing within the current wearable systems are shown, along with possible remedies.
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30
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Yin Y, Guo C, Li H, Yang H, Xiong F, Chen D. The Progress of Research into Flexible Sensors in the Field of Smart Wearables. SENSORS (BASEL, SWITZERLAND) 2022; 22:5089. [PMID: 35890768 PMCID: PMC9319532 DOI: 10.3390/s22145089] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 07/02/2022] [Accepted: 07/03/2022] [Indexed: 05/14/2023]
Abstract
In modern society, technology associated with smart sensors made from flexible materials is rapidly evolving. As a core component in the field of wearable smart devices (or 'smart wearables'), flexible sensors have the advantages of excellent flexibility, ductility, free folding properties, and more. When choosing materials for the development of sensors, reduced weight, elasticity, and wearer's convenience are considered as advantages, and are suitable for electronic skin, monitoring of health-related issues, biomedicine, human-computer interactions, and other fields of biotechnology. The idea behind wearable sensory devices is to enable their easy integration into everyday life. This review discusses the concepts of sensory mechanism, detected object, and contact form of flexible sensors, and expounds the preparation materials and their applicability. This is with the purpose of providing a reference for the further development of flexible sensors suitable for wearable devices.
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Affiliation(s)
- Yunlei Yin
- College of Textile, Zhongyuan University of Technology, Zhengzhou 450007, China; (C.G.); (H.L.); (H.Y.); (F.X.); (D.C.)
| | - Cheng Guo
- College of Textile, Zhongyuan University of Technology, Zhengzhou 450007, China; (C.G.); (H.L.); (H.Y.); (F.X.); (D.C.)
| | - Hong Li
- College of Textile, Zhongyuan University of Technology, Zhengzhou 450007, China; (C.G.); (H.L.); (H.Y.); (F.X.); (D.C.)
| | - Hongying Yang
- College of Textile, Zhongyuan University of Technology, Zhengzhou 450007, China; (C.G.); (H.L.); (H.Y.); (F.X.); (D.C.)
- Henan Province Collaborative Innovation Center of Textile and Garment Industry, Zhengzhou 450007, China
| | - Fan Xiong
- College of Textile, Zhongyuan University of Technology, Zhengzhou 450007, China; (C.G.); (H.L.); (H.Y.); (F.X.); (D.C.)
| | - Dongyi Chen
- College of Textile, Zhongyuan University of Technology, Zhengzhou 450007, China; (C.G.); (H.L.); (H.Y.); (F.X.); (D.C.)
- College of Automation Engineering, University of Electronic Science and Technology, Chengdu 611731, China
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31
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Batch Fabrication of a Polydimethylsiloxane Based Stretchable Capacitive Strain Gauge Sensor for Orthopedics. Polymers (Basel) 2022; 14:polym14122326. [PMID: 35745901 PMCID: PMC9228458 DOI: 10.3390/polym14122326] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 05/26/2022] [Accepted: 06/06/2022] [Indexed: 02/01/2023] Open
Abstract
Polymer-based capacitive strain gauges are a novel and promising concept for measuring large displacements and strains in various applications. These novel sensors allow for high strain, well above the maximum values achieved with state-of-the-art strain gauges (Typ. 1%). In recent years, a lot of interest in this technology has existed in orthopedics, where the sensors have been used to measure knee laxity caused by a tear of the anterior cruciate ligament (ACL), and for other ligament injuries. The validation of this technology in the field has a very low level of maturity, as no fast, reproducible, and reliable manufacturing process which allows mass production of sensors with low cost exists. For this reason, in this paper, a new approach for the fabrication of polymer-based capacitive strain gauges is proposed, using polydimethylsiloxane (PDMS) as base material. It allows (1) the fast manufacturing of sensor batches with reproducible geometry, (2) includes a fabrication step for embedding rigid electrical contacts on the sensors, and (3) is designed to produce sensor batches in which the size, the number, and the position of the sensors can be adapted to the patient’s anatomy. In the paper, the process repeatability and the robustness of the design are successfully proven. After 1000 large-strain elongation cycles, in the form of accelerated testing caused much higher strains than in the above-mentioned clinical scenario, the sensor’s electrical contacts remained in place and the functionalities were unaltered. Moreover, the prototype of a patient customizable patch, embedding multiple sensors, was produced.
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32
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Afzal U, Afzal F, Maryam K, Aslam M. Fabrication of flexible temperature sensors to explore indeterministic data analysis for robots as an application of Internet of Things. RSC Adv 2022; 12:17138-17145. [PMID: 35755584 PMCID: PMC9178695 DOI: 10.1039/d2ra03015b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 05/20/2022] [Indexed: 12/04/2022] Open
Abstract
The use of flexible electronic devices in different applications of Internet of Things, especially in robot technology, has gained importance to measure different physical factors such as temperature. Moreover, there is a need for a flexible and more informative approach to analyse the data. In this study, we report two flexible temperature sensors based on reduced graphene and multi-walled carbon nanotubes with high sensitivity and quick response and recovery times. The electrical properties of the sensors were studied using an LCR meter associated with a controlled chamber at 1 kHz. We used both classical and neutrosophic methods for analyzing the measured data of temperature sensors and found the more effective method by comparing their methods of analysis. The use of flexible electronic devices in different applications of Internet of Things, especially in robot technology, has gained importance to measure different physical factors such as temperature.![]()
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Affiliation(s)
- Usama Afzal
- Department of Physics, University of Education, Township Campus Lahore 54000 Pakistan
| | - Fatima Afzal
- School of Chemistry, University of the Punjab Lahore 54000 Pakistan
| | - Kanza Maryam
- School of Chemistry, University of the Punjab Lahore 54000 Pakistan
| | - Muhammad Aslam
- Departments of Statistics, Faculty of Science, King Abdulaziz University Jeddah 21551 Saudi Arabia
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33
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Di Tocco J, Lo Presti D, Rainer A, Schena E, Massaroni C. Silicone-Textile Composite Resistive Strain Sensors for Human Motion-Related Parameters. SENSORS 2022; 22:s22103954. [PMID: 35632361 PMCID: PMC9147119 DOI: 10.3390/s22103954] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/11/2022] [Accepted: 05/20/2022] [Indexed: 11/29/2022]
Abstract
In recent years, soft and flexible strain sensors have found application in wearable devices for monitoring human motion and physiological parameters. Conductive textile-based sensors are good candidates for developing these sensors. However, their robust electro-mechanical connection and susceptibility to environmental factors are still an open challenge to date. In this work, the manufacturing process of a silicone-textile composite resistive strain sensor based on a conductive resistive textile encapsulated into a dual-layer of silicone rubber is reported. In the working range typical of biomedical applications (up to 50%), the proposed flexible, skin-safe and moisture resistant strain sensor exhibited high sensitivity (gauge factor of −1.1), low hysteresis (maximum hysteresis error 3.2%) and ease of shaping in custom designs through a facile manufacturing process. To test the developed flexible sensor, two applicative scenarios covering the whole working range have been considered: the recording of the chest wall expansion during respiratory activity and the capture of the elbow flexion/extension movements.
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Affiliation(s)
- Joshua Di Tocco
- Unit of Measurements and Biomedical Instrumentation, Departmental Faculty of Engineering, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 00128 Rome, Italy; (J.D.T.); (D.L.P.); (C.M.)
| | - Daniela Lo Presti
- Unit of Measurements and Biomedical Instrumentation, Departmental Faculty of Engineering, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 00128 Rome, Italy; (J.D.T.); (D.L.P.); (C.M.)
| | - Alberto Rainer
- Unit of Tissue Engineering and Chemistry for Engineering, Departmental Faculty of Engineering, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 00128 Rome, Italy;
- Institute of Nanotechnology, National Research Council, Via Monteroni, 73100 Lecce, Italy
| | - Emiliano Schena
- Unit of Measurements and Biomedical Instrumentation, Departmental Faculty of Engineering, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 00128 Rome, Italy; (J.D.T.); (D.L.P.); (C.M.)
- Correspondence:
| | - Carlo Massaroni
- Unit of Measurements and Biomedical Instrumentation, Departmental Faculty of Engineering, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 00128 Rome, Italy; (J.D.T.); (D.L.P.); (C.M.)
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Goodband R, Bain CD, Staykova M. Comparative Study of Lipid- and Polymer-Supported Membranes Obtained by Vesicle Fusion. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:5674-5681. [PMID: 35471971 PMCID: PMC9097520 DOI: 10.1021/acs.langmuir.2c00266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 04/12/2022] [Indexed: 06/14/2023]
Abstract
We compare the fusion of giant lipid and block-copolymer vesicles on glass and poly(dimethylsiloxane) substrates. Both types of vesicles are similar in their ability to fuse to hydrophilic substrates and form patches with distinct heart or circular shapes. We use epifluorescence/confocal microscopy and atomic force microscopy on membrane patches to (i) characterize bilayer fluidity and patch-edge stability and (ii) follow the intermediate stages in the formation of continuous supported bilayers. Polymer membranes show much lower membrane fluidity and, unlike lipids, an inability of adjacent patches to fuse spontaneously into continuous membranes. We ascribe this effect to hydration repulsion forces acting between the patch edges, which can be diminished by increasing the sample temperature. We show that large areas of supported polymer membranes can be created by fusing giant vesicles on glass or poly(dimethylsiloxane) substrates and annealing their edges.
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Affiliation(s)
| | - Colin D. Bain
- Department
of Chemistry, Durham University, Durham DH1 3LE, U.K.
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35
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Perspective about Cellulose-Based Pressure and Strain Sensors for Human Motion Detection. BIOSENSORS 2022; 12:bios12040187. [PMID: 35448247 PMCID: PMC9025327 DOI: 10.3390/bios12040187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/04/2022] [Accepted: 03/16/2022] [Indexed: 12/26/2022]
Abstract
High-performance wearable sensors, especially resistive pressure and strain sensors, have shown to be promising approaches for the next generation of health monitoring. Besides being skin-friendly and biocompatible, the required features for such types of sensors are lightweight, flexible, and stretchable. Cellulose-based materials in their different forms, such as air-porous materials and hydrogels, can have advantageous properties to these sensors. For example, cellulosic sensors can present superior mechanical properties which lead to improved sensor performance. Here, recent advances in cellulose-based pressure and strain sensors for human motion detection are reviewed. The methodologies and materials for obtaining such devices and the highlights of pressure and strain sensor features are also described. Finally, the feasibility and the prospects of the field are discussed.
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36
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Zeng X, Deng HT, Wen DL, Li YY, Xu L, Zhang XS. Wearable Multi-Functional Sensing Technology for Healthcare Smart Detection. MICROMACHINES 2022; 13:254. [PMID: 35208378 PMCID: PMC8874439 DOI: 10.3390/mi13020254] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 01/30/2022] [Accepted: 01/31/2022] [Indexed: 11/21/2022]
Abstract
In recent years, considerable research efforts have been devoted to the development of wearable multi-functional sensing technology to fulfill the requirements of healthcare smart detection, and much progress has been achieved. Due to the appealing characteristics of flexibility, stretchability and long-term stability, the sensors have been used in a wide range of applications, such as respiration monitoring, pulse wave detection, gait pattern analysis, etc. Wearable sensors based on single mechanisms are usually capable of sensing only one physiological or motion signal. In order to measure, record and analyze comprehensive physical conditions, it is indispensable to explore the wearable sensors based on hybrid mechanisms and realize the integration of multiple smart functions. Herein, we have summarized various working mechanisms (resistive, capacitive, triboelectric, piezoelectric, thermo-electric, pyroelectric) and hybrid mechanisms that are incorporated into wearable sensors. More importantly, to make wearable sensors work persistently, it is meaningful to combine flexible power units and wearable sensors and form a self-powered system. This article also emphasizes the utility of self-powered wearable sensors from the perspective of mechanisms, and gives applications. Furthermore, we discuss the emerging materials and structures that are applied to achieve high sensitivity. In the end, we present perspectives on the outlooks of wearable multi-functional sensing technology.
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Affiliation(s)
- Xu Zeng
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China; (X.Z.); (H.-T.D.); (D.-L.W.); (Y.-Y.L.)
| | - Hai-Tao Deng
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China; (X.Z.); (H.-T.D.); (D.-L.W.); (Y.-Y.L.)
| | - Dan-Liang Wen
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China; (X.Z.); (H.-T.D.); (D.-L.W.); (Y.-Y.L.)
| | - Yao-Yao Li
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China; (X.Z.); (H.-T.D.); (D.-L.W.); (Y.-Y.L.)
| | - Li Xu
- Rehabilitation Department, Sichuan Provincial People’s Hospital, Chengdu 610072, China
| | - Xiao-Sheng Zhang
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China; (X.Z.); (H.-T.D.); (D.-L.W.); (Y.-Y.L.)
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37
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Mihara S, Takeoka S. Preparation and characterization of highly elongated polydimethylsiloxane nanosheets. POLYM ADVAN TECHNOL 2022. [DOI: 10.1002/pat.5591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Sho Mihara
- Graduate School of Advanced Science and Engineering Waseda University Tokyo Japan
- Waseda Research Institute for Science and Engineering Waseda University Tokyo Japan
| | - Shinji Takeoka
- Waseda Research Institute for Science and Engineering Waseda University Tokyo Japan
- Faculty of Science and Engineering Waseda University Tokyo Japan
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38
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Lin L, Chung CK. PDMS Microfabrication and Design for Microfluidics and Sustainable Energy Application: Review. MICROMACHINES 2021; 12:1350. [PMID: 34832762 PMCID: PMC8625467 DOI: 10.3390/mi12111350] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/15/2021] [Accepted: 10/26/2021] [Indexed: 12/18/2022]
Abstract
The polydimethylsiloxane (PDMS) is popular for wide application in various fields of microfluidics, microneedles, biology, medicine, chemistry, optics, electronics, architecture, and emerging sustainable energy due to the intrinsic non-toxic, transparent, flexible, stretchable, biocompatible, hydrophobic, insulating, and negative triboelectric properties that meet different requirements. For example, the flexibility, biocompatibility, non-toxicity, good stability, and high transparency make PDMS a good candidate for the material selection of microfluidics, microneedles, biomedical, and chemistry microchips as well as for optical examination and wearable electronics. However, the hydrophobic surface and post-surface-treatment hydrophobic recovery impede the development of self-driven capillary microchips. How to develop a long-term hydrophilicity treatment for PDMS is crucial for capillary-driven microfluidics-based application. The dual-tone PDMS-to-PDMS casting for concave-and-convex microstructure without stiction is important for simplifying the process integration. The emerging triboelectric nanogenerator (TENG) uses the transparent flexible PDMS as the high negative triboelectric material to make friction with metals or other positive-triboelectric material for harvesting sustainably mechanical energy. The morphology of PDMS is related to TENG performance. This review will address the above issues in terms of PDMS microfabrication and design for the efficient micromixer, microreactor, capillary pump, microneedles, and TENG for more practical applications in the future.
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Affiliation(s)
| | - Chen-Kuei Chung
- Department of Mechanical Engineering and Core Facility Center, National Cheng Kung University, Tainan 701, Taiwan;
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Fabrication of Soft Tissue Scaffold-Mimicked Microelectrode Arrays Using Enzyme-Mediated Transfer Printing. MICROMACHINES 2021; 12:mi12091057. [PMID: 34577700 PMCID: PMC8472004 DOI: 10.3390/mi12091057] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/24/2021] [Accepted: 08/26/2021] [Indexed: 12/29/2022]
Abstract
Hydrogels are the ideal materials in the development of implanted bioactive neural interfaces because of the nerve tissue-mimicked physical and biological properties that can enhance neural interfacing compatibility. However, the integration of hydrogels and rigid/dehydrated electronic microstructure is challenging due to the non-reliable interfacial bonding, whereas hydrogels are not compatible with most conditions required for the micromachined fabrication process. Herein, we propose a new enzyme-mediated transfer printing process to design an adhesive biological hydrogel neural interface. The donor substrate was fabricated via photo-crosslinking of gelatin methacryloyl (GelMA) containing various conductive nanoparticles (NPs), including Ag nanowires (NWs), Pt NWs, and PEDOT:PSS, to form a stretchable conductive bioelectrode, called NP-doped GelMA. On the other hand, a receiver substrate composed of microbial transglutaminase-incorporated gelatin (mTG-Gln) enabled simultaneous temporally controlled gelation and covalent bond-enhanced adhesion to achieve one-step transfer printing of the prefabricated NP-doped GelMA features. The integrated hydrogel microelectrode arrays (MEA) were adhesive, and mechanically/structurally bio-compliant with stable conductivity. The devices were structurally stable in moisture to support the growth of neuronal cells. Despite that the introduction of AgNW and PEDOT:PSS NPs in the hydrogels needed further study to avoid cell toxicity, the PtNW-doped GelMA exhibited a comparable live cell density. This Gln-based MEA is expected to be the next-generation bioactive neural interface.
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40
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Nesser H, Lubineau G. Achieving Super Sensitivity in Capacitive Strain Sensing by Electrode Fragmentation. ACS APPLIED MATERIALS & INTERFACES 2021; 13:36062-36070. [PMID: 34309375 DOI: 10.1021/acsami.1c07704] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Accurate wireless strain monitoring is critical for many engineering applications. Capacitive strain sensors are well suited for remote sensing but currently have a limited sensitivity. This study presents a new approach for improving the sensitivity of electrical capacitance change-based strain sensors. Our technology is based on a dielectric elastomer layer laminated between two fragmented electrodes (i.e., carbon nanotube papers) that, by design, experiences a significant change in resistance (from Ω to MΩ) when stretched and makes the sensor behave as a transmission line, a well-known structure in telecommunication engineering. The strain-dependent voltage attenuation over the structure length results in a large variation of the effective capacitance (gauge factor exceeding 37 at 3% strain).
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Affiliation(s)
- Hussein Nesser
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division (PSE), COHMAS Laboratory, Thuwal 23955-6900, Saudi Arabia
| | - Gilles Lubineau
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division (PSE), COHMAS Laboratory, Thuwal 23955-6900, Saudi Arabia
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41
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Flexible and Transparent Polymer-Based Optical Humidity Sensor. SENSORS 2021; 21:s21113674. [PMID: 34070545 PMCID: PMC8198816 DOI: 10.3390/s21113674] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/19/2021] [Accepted: 05/21/2021] [Indexed: 11/16/2022]
Abstract
Thin spin-coated polymer films of amphiphilic copolymer obtained by partial acetalization of poly (vinyl alcohol) are used as humidity-sensitive media. They are deposited on polymer substrate (PET) in order to obtain a flexible humidity sensor. Pre-metallization of substrate is implemented for increasing the optical contrast of the sensor, thus improving the sensitivity. The morphology of the sensors is studied by surface profiling, while the transparency of the sensor is controlled by transmittance measurements. The sensing behavior is evaluated through monitoring of transmittance values at different levels of relative humidity gradually changing in the range 5-95% and the influence of up to 1000 bending deformations is estimated by determining the hysteresis and sensitivity of the flexible sensor after each set of deformations. The successful development of a flexible sensor for optical monitoring of humidity in a wide humidity range is demonstrated and discussed.
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42
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Lin CB, Chuang YF, Yang F, Lee S. Kinetics for the Slip Motion of Ripple Dislocations on Gold-Coated Poly(dimethylsiloxane). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:5943-5949. [PMID: 33951393 DOI: 10.1021/acs.langmuir.1c00487] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Understanding the evolution of the defects in surface patterns is of practical importance to improve the performance and structural durability of the pattern-based micro- and nanodevices. In this work, we investigate the effects of temperature, compressive strain, and relative direction of the compression to the prestretch on the slip motion of ripple dislocations formed on the surface of gold-coated poly(dimethylsiloxane) films. Applying compression in the direction parallel to the direction of prestretch cannot cause the slip motion of the ripple dislocations. The initial velocity of the slip motion of the ripple dislocations increases with the increases in temperature and compressive strain. The temperature dependence of the ratios of the configuration force to the viscous coefficient and the viscous coefficient to the effective mass of the ripple dislocations follows the Arrhenius equation.
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Affiliation(s)
- C B Lin
- Mechanical and Electro-Mechanical Engineering, Tamkang University, New Taipei City 251301, Taiwan
| | - Yu-Fan Chuang
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 300, Taiwan
| | - Fuqian Yang
- Department of Chemical and Materials Engineering, University of Kentucky Materials Program, Lexington, Kentucky 40506, United States
| | - Sanboh Lee
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 300, Taiwan
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43
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Zullo G, Silvestroni AL, Candiotto G, Koptyug A, Petrone N. A Novel Multi-Axial Pressure Sensor Probe for Measuring Triaxial Stress States Inside Soft Materials. SENSORS 2021; 21:s21103487. [PMID: 34067759 PMCID: PMC8155985 DOI: 10.3390/s21103487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/07/2021] [Accepted: 05/13/2021] [Indexed: 11/22/2022]
Abstract
This paper presents the concept, design, construction, and validation of a novel probe based on the hexadic disposition of six pressure sensors suitable for measuring triaxial stress states inside bulky soft materials. The measurement of triaxial stress states inside bulk materials such as brain tissue surrogates is a challenging task needed to investigate internal organs’ stress states and validate FE models. The purpose of the work was the development and validation of a 17 × 17 × 17 mm probe containing six pressure sensors. To do so, six piezoresistive pressure sensors of 6 mm diameter were arranged into an hexad at three cartesian axes and bisecting angles, based on the analytical solution of the stress tensor. The resulting probe was embedded in a soft silicone rubber of known characteristics, calibrated under cyclic compression and shear in three orientations, and statically validated with combined loads. A calibration matrix was computed, and validation tests allowed us to estimate Von Mises stress under combined stress with an error below 6%. Hence, the proposed probe design and method can give indications about the complex stress state developing internally to soft materials under triaxial high-strain fields, opening applications in the analysis of biological models or physical surrogates involving parenchyma organs.
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Affiliation(s)
- Giuseppe Zullo
- Department of Industrial Engineering, University of Padua, Via Venezia 1, 35131 Padua, Italy; (G.Z.); (A.L.S.); (G.C.)
| | - Anna Leidy Silvestroni
- Department of Industrial Engineering, University of Padua, Via Venezia 1, 35131 Padua, Italy; (G.Z.); (A.L.S.); (G.C.)
| | - Gianluca Candiotto
- Department of Industrial Engineering, University of Padua, Via Venezia 1, 35131 Padua, Italy; (G.Z.); (A.L.S.); (G.C.)
| | - Andrey Koptyug
- Department of Quality and Mechanical Engineering, Mid Sweden University, Campus Östersund Kunskapens väg 8, SE-831 25 Östersund, Sweden;
| | - Nicola Petrone
- Department of Industrial Engineering, University of Padua, Via Venezia 1, 35131 Padua, Italy; (G.Z.); (A.L.S.); (G.C.)
- Correspondence: ; Tel.: +39-049-827-6761
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44
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Wen DL, Sun DH, Huang P, Huang W, Su M, Wang Y, Han MD, Kim B, Brugger J, Zhang HX, Zhang XS. Recent progress in silk fibroin-based flexible electronics. MICROSYSTEMS & NANOENGINEERING 2021; 7:35. [PMID: 34567749 PMCID: PMC8433308 DOI: 10.1038/s41378-021-00261-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Accepted: 02/16/2021] [Indexed: 05/04/2023]
Abstract
With the rapid development of the Internet of Things (IoT) and the emergence of 5G, traditional silicon-based electronics no longer fully meet market demands such as nonplanar application scenarios due to mechanical mismatch. This provides unprecedented opportunities for flexible electronics that bypass the physical rigidity through the introduction of flexible materials. In recent decades, biological materials with outstanding biocompatibility and biodegradability, which are considered some of the most promising candidates for next-generation flexible electronics, have received increasing attention, e.g., silk fibroin, cellulose, pectin, chitosan, and melanin. Among them, silk fibroin presents greater superiorities in biocompatibility and biodegradability, and moreover, it also possesses a variety of attractive properties, such as adjustable water solubility, remarkable optical transmittance, high mechanical robustness, light weight, and ease of processing, which are partially or even completely lacking in other biological materials. Therefore, silk fibroin has been widely used as fundamental components for the construction of biocompatible flexible electronics, particularly for wearable and implantable devices. Furthermore, in recent years, more attention has been paid to the investigation of the functional characteristics of silk fibroin, such as the dielectric properties, piezoelectric properties, strong ability to lose electrons, and sensitivity to environmental variables. Here, this paper not only reviews the preparation technologies for various forms of silk fibroin and the recent progress in the use of silk fibroin as a fundamental material but also focuses on the recent advanced works in which silk fibroin serves as functional components. Additionally, the challenges and future development of silk fibroin-based flexible electronics are summarized. (1) This review focuses on silk fibroin serving as active functional components to construct flexible electronics. (2) Recent representative reports on flexible electronic devices that applied silk fibroin as fundamental supporting components are summarized. (3) This review summarizes the current typical silk fibroin-based materials and the corresponding advanced preparation technologies. (4) The current challenges and future development of silk fibroin-based flexible electronic devices are analyzed.
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Affiliation(s)
- Dan-Liang Wen
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, 611731 China
| | - De-Heng Sun
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, 611731 China
| | - Peng Huang
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, 611731 China
| | - Wen Huang
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, 611731 China
| | - Meng Su
- CIRMM, Institute of Industrial Science, The University of Tokyo, Tokyo, 153-8505 Japan
| | - Ya Wang
- Microsystems Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Meng-Di Han
- Institute of Microelectronics, Peking University, 100087 Beijing, China
| | - Beomjoon Kim
- CIRMM, Institute of Industrial Science, The University of Tokyo, Tokyo, 153-8505 Japan
| | - Juergen Brugger
- Microsystems Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Hai-Xia Zhang
- Institute of Microelectronics, Peking University, 100087 Beijing, China
| | - Xiao-Sheng Zhang
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, 611731 China
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45
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Han F, Li M, Ye H, Zhang G. Materials, Electrical Performance, Mechanisms, Applications, and Manufacturing Approaches for Flexible Strain Sensors. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:1220. [PMID: 34063165 PMCID: PMC8148098 DOI: 10.3390/nano11051220] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 04/30/2021] [Accepted: 05/01/2021] [Indexed: 12/13/2022]
Abstract
With the recent great progress made in flexible and wearable electronic materials, the upcoming next generation of skin-mountable and implantable smart devices holds extensive potential applications for the lifestyle modifying, including personalized health monitoring, human-machine interfaces, soft robots, and implantable biomedical devices. As a core member within the wearable electronics family, flexible strain sensors play an essential role in the structure design and functional optimization. To further enhance the stretchability, flexibility, sensitivity, and electricity performances of the flexible strain sensors, enormous efforts have been done covering the materials design, manufacturing approaches and various applications. Thus, this review summarizes the latest advances in flexible strain sensors over recent years from the material, application, and manufacturing strategies. Firstly, the critical parameters measuring the performances of flexible strain sensors and materials development contains different flexible substrates, new nano- and hybrid- materials are introduced. Then, the developed working mechanisms, theoretical analysis, and computational simulation are presented. Next, based on different material design, diverse applications including human motion detection and health monitoring, soft robotics and human-machine interface, implantable devices, and biomedical applications are highlighted. Finally, synthesis consideration of the massive production industry of flexible strain sensors in the future; different fabrication approaches that are fully expected are classified and discussed.
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Affiliation(s)
- Fei Han
- Institute of Future Lighting, Academy for Engineering and Technology, Fudan University, Shanghai 200433, China; (F.H.); (M.L.)
- Shenzhen Institute of Wide-Bandgap Semiconductors, Shenzhen 518055, China
| | - Min Li
- Institute of Future Lighting, Academy for Engineering and Technology, Fudan University, Shanghai 200433, China; (F.H.); (M.L.)
| | - Huaiyu Ye
- Shenzhen Institute of Wide-Bandgap Semiconductors, Shenzhen 518055, China
| | - Guoqi Zhang
- Institute of Future Lighting, Academy for Engineering and Technology, Fudan University, Shanghai 200433, China; (F.H.); (M.L.)
- Shenzhen Institute of Wide-Bandgap Semiconductors, Shenzhen 518055, China
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46
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Gao J, He S, Nag A. Electrochemical Detection of Glucose Molecules Using Laser-Induced Graphene Sensors: A Review. SENSORS (BASEL, SWITZERLAND) 2021; 21:2818. [PMID: 33923790 PMCID: PMC8073164 DOI: 10.3390/s21082818] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 04/06/2021] [Accepted: 04/14/2021] [Indexed: 02/07/2023]
Abstract
This paper deals with recent progress in the use of laser-induced graphene sensors for the electrochemical detection of glucose molecules. The exponential increase in the exploitation of the laser induction technique to generate porous graphene from polymeric and other naturally occurring materials has provided a podium for researchers to fabricate flexible sensors with high dynamicity. These sensors have been employed largely for electrochemical applications due to their distinct advantages like high customization in their structural dimensions, enhanced characteristics and easy roll-to-roll production. These laser-induced graphene (LIG)-based sensors have been employed for a wide range of sensorial applications, including detection of ions at varying concentrations. Among the many pivotal electrochemical uses in the biomedical sector, the use of these prototypes to monitor the concentration of glucose molecules is constantly increasing due to the essentiality of the presence of these molecules at specific concentrations in the human body. This paper shows a categorical classification of the various uses of these sensors based on the type of materials involved in the fabrication of sensors. The first category constitutes examples where the electrodes have been functionalized with various forms of copper and other types of metallic nanomaterials. The second category includes other miscellaneous forms where the use of both pure and composite forms of LIG-based sensors has been shown. Finally, the paper concludes with some of the possible measures that can be taken to enhance the use of this technique to generate optimized sensing prototypes for a wider range of applications.
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Affiliation(s)
- Jingrong Gao
- College of Light Industry and Food Science, South China University of Technology, Guangzhou 510006, China;
| | - Shan He
- School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China;
- Institute for NanoScale Science and Technology, College of Science and Engineering, Flinders University, 5042 Bedford Park, Australia
| | - Anindya Nag
- School of Information Science and Engineering, Shandong University, Jinan 251600, China
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Jeong SY, Lee JU, Hong SM, Lee CW, Hwang SH, Cho SC, Shin BS. Highly Skin-Conformal Laser-Induced Graphene-Based Human Motion Monitoring Sensor. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:951. [PMID: 33917897 PMCID: PMC8068237 DOI: 10.3390/nano11040951] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 04/01/2021] [Accepted: 04/07/2021] [Indexed: 12/02/2022]
Abstract
Bio-compatible strain sensors based on elastomeric conductive polymer composites play pivotal roles in human monitoring devices. However, fabricating highly sensitive and skin-like (flexible and stretchable) strain sensors with broad working range is still an enormous challenge. Herein, we report on a novel fabrication technology for building elastomeric conductive skin-like composite by mixing polymer solutions. Our e-skin substrates were fabricated according to the weight of polydimethylsiloxane (PDMS) and photosensitive polyimide (PSPI) solutions, which could control substrate color. An e-skin and 3-D flexible strain sensor was developed with the formation of laser induced graphene (LIG) on the skin-like substrates. For a one-step process, Laser direct writing (LDW) was employed to construct superior durable LIG/PDMS/PSPI composites with a closed-pore porous structure. Graphene sheets of LIG coated on the closed-porous structure constitute a deformable conductive path. The LIG integrated with the closed-porous structure intensifies the deformation of the conductive network when tensile strain is applied, which enhances the sensitivity. Our sensor can efficiently monitor not only energetic human motions but also subtle oscillation and physiological signals for intelligent sound sensing. The skin-like strain sensor showed a perfect combination of ultrawide sensing range (120% strain), large sensitivity (gauge factor of ~380), short response time (90 ms) and recovery time (140 ms), as well as superior stability. Our sensor has great potential for innovative applications in wearable health-monitoring devices, robot tactile systems, and human-machine interface systems.
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Affiliation(s)
- Sung-Yeob Jeong
- Department of Mechanical Engineering, The University of Tokyo, Tokyo 113-8656, Japan;
| | - Jun-Uk Lee
- Department of Cogno-Mechatronics Engineering, Pusan National University, Pusan 46241, Korea; (J.-U.L.); (C.-W.L.); (S.-H.H.); (S.-C.C.)
| | - Sung-Moo Hong
- Interdisciplinary Department for Advanced Innovative Manufacturing Engineering, Pusan National University, Pusan 46241, Korea;
| | - Chan-Woo Lee
- Department of Cogno-Mechatronics Engineering, Pusan National University, Pusan 46241, Korea; (J.-U.L.); (C.-W.L.); (S.-H.H.); (S.-C.C.)
| | - Sung-Hwan Hwang
- Department of Cogno-Mechatronics Engineering, Pusan National University, Pusan 46241, Korea; (J.-U.L.); (C.-W.L.); (S.-H.H.); (S.-C.C.)
| | - Su-Chan Cho
- Department of Cogno-Mechatronics Engineering, Pusan National University, Pusan 46241, Korea; (J.-U.L.); (C.-W.L.); (S.-H.H.); (S.-C.C.)
| | - Bo-Sung Shin
- Interdisciplinary Department for Advanced Innovative Manufacturing Engineering, Pusan National University, Pusan 46241, Korea;
- Department of Optics and Mechatronics Engineering, Pusan National University, Pusan 46241, Korea
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Valarezo Añazco E, Han SJ, Kim K, Lopez PR, Kim TS, Lee S. Hand Gesture Recognition Using Single Patchable Six-Axis Inertial Measurement Unit via Recurrent Neural Networks. SENSORS (BASEL, SWITZERLAND) 2021; 21:1404. [PMID: 33671364 PMCID: PMC7922880 DOI: 10.3390/s21041404] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/09/2021] [Accepted: 02/09/2021] [Indexed: 12/14/2022]
Abstract
Recording human gestures from a wearable sensor produces valuable information to implement control gestures or in healthcare services. The wearable sensor is required to be small and easily worn. Advances in miniaturized sensor and materials research produces patchable inertial measurement units (IMUs). In this paper, a hand gesture recognition system using a single patchable six-axis IMU attached at the wrist via recurrent neural networks (RNN) is presented. The IMU comprises IC-based electronic components on a stretchable, adhesive substrate with serpentine-structured interconnections. The proposed patchable IMU with soft form-factors can be worn in close contact with the human body, comfortably adapting to skin deformations. Thus, signal distortion (i.e., motion artifacts) produced for vibration during the motion is minimized. Also, our patchable IMU has a wireless communication (i.e., Bluetooth) module to continuously send the sensed signals to any processing device. Our hand gesture recognition system was evaluated, attaching the proposed patchable six-axis IMU on the right wrist of five people to recognize three hand gestures using two models based on recurrent neural nets. The RNN-based models are trained and validated using a public database. The preliminary results show that our proposed patchable IMU have potential to continuously monitor people's motions in remote settings for applications in mobile health, human-computer interaction, and control gestures recognition.
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Affiliation(s)
- Edwin Valarezo Añazco
- Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea; (E.V.A.); (S.J.H.); (K.K.); (P.R.L.); (T.-S.K.)
- Faculty of Engineering in Electricity and Computation, FIEC, Escuela Superior Politécnica del Litoral, ESPOL, Guayaquil EC090112, Ecuador
| | - Seung Ju Han
- Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea; (E.V.A.); (S.J.H.); (K.K.); (P.R.L.); (T.-S.K.)
| | - Kangil Kim
- Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea; (E.V.A.); (S.J.H.); (K.K.); (P.R.L.); (T.-S.K.)
| | - Patricio Rivera Lopez
- Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea; (E.V.A.); (S.J.H.); (K.K.); (P.R.L.); (T.-S.K.)
| | - Tae-Seong Kim
- Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea; (E.V.A.); (S.J.H.); (K.K.); (P.R.L.); (T.-S.K.)
| | - Sangmin Lee
- Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea; (E.V.A.); (S.J.H.); (K.K.); (P.R.L.); (T.-S.K.)
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Nag A, Alahi MEE, Mukhopadhyay SC, Liu Z. Multi-Walled Carbon Nanotubes-Based Sensors for Strain Sensing Applications. SENSORS (BASEL, SWITZERLAND) 2021; 21:1261. [PMID: 33578782 PMCID: PMC7916448 DOI: 10.3390/s21041261] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 01/22/2021] [Accepted: 02/03/2021] [Indexed: 12/28/2022]
Abstract
The use of multi-walled carbon nanotube (MWCNT)-based sensors for strain-strain applications is showcased in this paper. Extensive use of MWCNTs has been done for the fabrication and implementation of flexible sensors due to their enhanced electrical, mechanical, and thermal properties. These nanotubes have been deployed both in pure and composite forms for obtaining highly efficient sensors in terms of sensitivity, robustness, and longevity. Among the wide range of applications that MWCNTs have been exploited for, strain-sensing has been one of the most popular ones due to the high mechanical flexibility of these carbon allotropes. The MWCNT-based sensors have been able to deduce a broad spectrum of macro- and micro-scaled tensions through structural changes. This paper highlights some of the well-approved conjugations of MWCNTs with different kinds of polymers and other conductive nanomaterials to form the electrodes of the strain sensors. It also underlines some of the measures that can be taken in the future to improve the quality of these MWCNT-based sensors for strain-related applications.
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Affiliation(s)
- Anindya Nag
- School of Information Science and Engineering, Shandong University, Jinan 251600, China;
| | - Md. Eshrat E Alahi
- The Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China;
| | | | - Zhi Liu
- School of Information Science and Engineering, Shandong University, Jinan 251600, China;
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Quiñones-Pérez M, Cieza RJ, Ngo BKD, Grunlan MA, Domenech M. Amphiphilic silicones to reduce the absorption of small hydrophobic molecules. Acta Biomater 2021; 121:339-348. [PMID: 33271355 DOI: 10.1016/j.actbio.2020.11.041] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/23/2020] [Accepted: 11/25/2020] [Indexed: 12/19/2022]
Abstract
Silicones (i.e. crosslinked poly(dimethylsiloxane), PDMS) are commonly used material for microfluidic device fabrication. Nonetheless, due to the uncontrollable absorption of small hydrophobic molecules (<1 kDa) into the bulk, its applicability to cell-based drug assays and sensing applications has been limited. Here, we demonstrate the use of substrates made of silicones bulk modified with a poly(ethylene oxide) silane amphiphile (PEO-SA) to reduce hydrophobic small molecule sequestration for cell-based assays. Modified silicone substrates were generated with concentrations of 2 wt.%, 9 wt.% and, 14 wt.% PEO-SA. Incorporation of PEO-SA into the silicone bulk was assessed by FTIR analysis in addition to water contact angle analysis to evaluate surface hydrophobicity. Cell toxicity, absorption of small hydrophobic drugs, and cell response to hydrophobic molecules were also evaluated. Results showed that the incorporation of the PEO-SA into the silicone led to a reduction in water contact angle from 114° to as low as 16° that was stable for at least three months. The modified silicones showed viability values above 85% for NIH-3T3, MCF7, MDA-MB-468, and MDA-MB-231 cell lines. A drug response assay using tamoxifen and the MCF7 cell line showed full recovery of cell toxicity response when exposed to PDMS modified with 9 wt.% or 14 wt.% PEO-SA compared to tissue culture plastic. Therefore, our study supports the use of PEO-SA at concentrations of 9 wt.% or higher for enhanced surface wettability and reduced absorption of small hydrophobic molecules in PDMS-based platforms.
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Affiliation(s)
- Manuel Quiñones-Pérez
- Industrial Biotechnology Program, University of Puerto Rico Mayagüez, PR-108, Mayagüez, PR 00682, Puerto Rico
| | - Ruben J Cieza
- Chemical Engineering Department, University of Puerto Rico Mayagüez, PR-108, Mayagüez, PR 00682, Puerto Rico
| | - Bryan Khai D Ngo
- Department of Biomedical Engineering, Department of Materials Science & Engineering, Department of Chemistry, Texas A&M University, College Station, TX 77843, USA
| | - Melissa A Grunlan
- Department of Biomedical Engineering, Department of Materials Science & Engineering, Department of Chemistry, Texas A&M University, College Station, TX 77843, USA
| | - Maribella Domenech
- Chemical Engineering Department, University of Puerto Rico Mayagüez, PR-108, Mayagüez, PR 00682, Puerto Rico.
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