1
|
Feng J, Ao H, Cao P, Yang T, Xing B. Flexible tactile sensors with interlocking serrated structures based on stretchable multiwalled carbon nanotube/silver nanowire/silicone rubber composites. RSC Adv 2024; 14:13934-13943. [PMID: 38686300 PMCID: PMC11056684 DOI: 10.1039/d4ra00381k] [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: 01/15/2024] [Accepted: 04/12/2024] [Indexed: 05/02/2024] Open
Abstract
Flexible tactile sensors have attracted significant interest because of their application scope in the fields of biomedicine, motion detection, and human-computer interaction. However, the development of tactile sensors with high sensitivity and flexibility remains a critical challenge. This study develops a patterned, stretchable, and fully elastomeric multiwalled carbon nanotube (MWCNT)/silver nanowire (Ag NW)/silicone rubber (SR) composite. The addition of Ag NWs to MWCNTs enhances the transmission path of the conductive network, yielding a CNT/Ag NW/SR composite with a sensitivity coefficient of 40. This characteristic renders it suitable for use as a piezoresistive sensing material. The interlocking sawtooth structure can convert the mechanical stimuli of the sensor to the tensile strain of the composite, thereby enhancing its sensitivity and flexibility. Experimental results indicate that the developed tactile sensor exhibited a sensitivity of 2.82 N-1 at 0-0.5 N and 1.51 N-1 at 0.5-2 N. These haptic sensors also demonstrate good dynamic response, repeatability, and long life. Furthermore, experimental results show that these haptic sensors exhibit high reproducibility, fast dynamic response, and good mechanical and electrical stability. Because of these exceptional properties, the as-prepared sensor can be applied in the development of smart robots, prosthetics, and wearable devices.
Collapse
Affiliation(s)
- Junyan Feng
- College of Mechanical and Electronic Engineering, Jiaxing Nanhu University Jiaxing 314001 China
| | - Hezheng Ao
- College of Mechanical Engineering, Zhejiang University of Technology Hangzhou 310014 Zhejiang China
| | - Peng Cao
- College of Mechanical Engineering, Zhejiang University of Technology Hangzhou 310014 Zhejiang China
| | - Tao Yang
- College of Mechanical Engineering, Zhejiang University of Technology Hangzhou 310014 Zhejiang China
| | - Bo Xing
- College of Information Science and Engineering, Jiaxing University Jiaxing 314000 China
| |
Collapse
|
2
|
Hu T, Sheng B. A Highly Sensitive Strain Sensor with Wide Linear Sensing Range Prepared on a Hybrid-Structured CNT/Ecoflex Film via Local Regulation of Strain Distribution. ACS APPLIED MATERIALS & INTERFACES 2024. [PMID: 38603806 DOI: 10.1021/acsami.4c00648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/13/2024]
Abstract
With the development of information technology, high-performance wearable strain sensors with high sensitivity and stretchability have played a significant role in motion detection. However, many high-sensitivity and outstanding-stretchability strain sensors possess a limited linear sensing range, which limits the enhancement of the flexible strain sensors' performance. Herein, we develop a hybrid-structured carbon nanotube (CNT)/Ecoflex strain sensor with laser-engraved grooves along with punched circular holes in a composite CNT/Ecoflex film by vacuum filtration and permeation. By optimizing the distribution of grooves and circular holes, the strain in the sensing layer can be locally regulated, which alters the morphology of cracks under strain and allows the hybrid-structured CNT/Ecoflex strain sensor to simultaneously exhibit high sensitivity (GF = 43.8) as well as a wide linear sensing range (200%). On the basis of excellent performance, the hybrid-structured CNT/Ecoflex strain sensor is capable of detecting movements in various parts of the human body, including movements of larynx and joint bending.
Collapse
Affiliation(s)
- Tao Hu
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Bin Sheng
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| |
Collapse
|
3
|
Lin Y, Shull PB, Chossat JB. Design of a Wearable Real-Time Hand Motion Tracking System Using an Array of Soft Polymer Acoustic Waveguides. Soft Robot 2024; 11:282-295. [PMID: 37870761 DOI: 10.1089/soro.2022.0091] [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] [Indexed: 10/24/2023] Open
Abstract
Robust hand motion tracking holds promise for improved human-machine interaction in diverse fields, including virtual reality, and automated sign language translation. However, current wearable hand motion tracking approaches are typically limited in detection performance, wearability, and durability. This article presents a hand motion tracking system using multiple soft polymer acoustic waveguides (SPAWs). The innovative use of SPAWs as strain sensors offers several advantages that address the limitations. SPAWs are easily manufactured by casting a soft polymer shaped as a soft acoustic waveguide and containing a commercially available small ceramic piezoelectric transducer. When used as strain sensors, SPAWs demonstrate high stretchability (up to 100%), high linearity (R2 > 0.996 in all quasi-static, dynamic, and durability tensile tests), negligible hysteresis (<0.7410% under strain of up to 100%), excellent repeatability, and outstanding durability (up to 100,000 cycles). SPAWs also show high accuracy for continuous finger angle estimation (average root-mean-square errors [RMSE] <2.00°) at various flexion-extension speeds. Finally, a hand-tracking system is designed based on a SPAW array. An example application is developed to demonstrate the performance of SPAWs in real-time hand motion tracking in a three-dimensional (3D) virtual environment. To our knowledge, the system detailed in this article is the first to use soft acoustic waveguides to capture human motion. This work is part of an ongoing effort to develop soft sensors using both time and frequency domains, with the goal of extracting decoupled signals from simple sensing structures. As such, it represents a novel and promising path toward soft, simple, and wearable multimodal sensors.
Collapse
Affiliation(s)
- Yuan Lin
- Robotics Institute, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Peter B Shull
- Robotics Institute, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Jean-Baptiste Chossat
- Soft Transducers Laboratory, École Polytechnique Fédérale de Lausanne, Neuchâtel, Switzerland
| |
Collapse
|
4
|
Jiang Q, Liang X, Chen Z, Zou Y, Zhu S, Min R, Huang Q, Yang Z, Li Z, Chen Q. Wearable strain sensor integrating mechanoluminescent fiber with a flexible printed circuit. OPTICS LETTERS 2024; 49:1221-1224. [PMID: 38426978 DOI: 10.1364/ol.516883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Accepted: 02/11/2024] [Indexed: 03/02/2024]
Abstract
This paper reports an optical strain sensor that integrates a self-powered mechanoluminescent (ML) elastic fiber with a flexible circuit. The inclusion of an alumina nanoparticle as the additive results in seven-fold enhancement of ML intensity while maintaining flexibility of 120% strain. The sensor facilitates the detection of strain and stretching speed. It attains a sensitivity of 0.0022 lx/(1% strain) and a resolution of 0.2% strain, respectively. We have successfully applied it to detect bending motions of the finger, wrist, and elbow. This wearable strain sensor holds promise for diverse applications in wearable technology.
Collapse
|
5
|
Li S, Zhang J, He J, Liu W, Wang Y, Huang Z, Pang H, Chen Y. Functional PDMS Elastomers: Bulk Composites, Surface Engineering, and Precision Fabrication. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2304506. [PMID: 37814364 DOI: 10.1002/advs.202304506] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Indexed: 10/11/2023]
Abstract
Polydimethylsiloxane (PDMS)-the simplest and most common silicone compound-exemplifies the central characteristics of its class and has attracted tremendous research attention. The development of PDMS-based materials is a vivid reflection of the modern industry. In recent years, PDMS has stood out as the material of choice for various emerging technologies. The rapid improvement in bulk modification strategies and multifunctional surfaces has enabled a whole new generation of PDMS-based materials and devices, facilitating, and even transforming enormous applications, including flexible electronics, superwetting surfaces, soft actuators, wearable and implantable sensors, biomedicals, and autonomous robotics. This paper reviews the latest advances in the field of PDMS-based functional materials, with a focus on the added functionality and their use as programmable materials for smart devices. Recent breakthroughs regarding instant crosslinking and additive manufacturing are featured, and exciting opportunities for future research are highlighted. This review provides a quick entrance to this rapidly evolving field and will help guide the rational design of next-generation soft materials and devices.
Collapse
Affiliation(s)
- Shaopeng Li
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Jiaqi Zhang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Jian He
- Yizhi Technology (Shanghai) Co., Ltd, No. 99 Danba Road, Putuo District, Shanghai, 200062, China
| | - Weiping Liu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, China
- Center for Composites, COMAC Shanghai Aircraft Manufacturing Co. Ltd, Shanghai, 201620, China
| | - YuHuang Wang
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA
- Maryland NanoCenter, University of Maryland, College Park, MD, 20742, USA
| | - Zhongjie Huang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Huan Pang
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu, 225009, China
| | - Yiwang Chen
- National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education, Jiangxi Normal University, 99 Ziyang Avenue, Nanchang, 330022, China
| |
Collapse
|
6
|
Zhou J, Zhao S, Tang L, Zhang D, Sheng B. Programmable and Weldable Superelastic EGaIn/TPU Composite Fiber by Wet Spinning for Flexible Electronics. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 38031357 DOI: 10.1021/acsami.3c11068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
As an essential component of flexible electronics, superelastic conductive fibers with good mechanical and electrical properties have drawn significant attention, especially in their preparation. In this study, we prepared a superelastic conductive fiber composed of eutectic gallium-indium (EGaIn) and thermoplastic polyurethane (TPU) by simple wet spinning. The composite conductive fiber with a liquid metal (LM) content of 85 wt % achieved a maximum strain at a break of 659.2%, and after the conductive pathway in the porous structure of the composite fibers was fully activated, high conductivity (1.2 × 105 S/m) was achieved with 95 wt % LM by mechanical sintering and training processes. The prepared conductive fibers exhibited a stable resistive response as the fibers were strained and could be sewn into fabrics and used as wearable strain sensors to monitor various human motions. These conductive fibers can be molded into helical by heating, and they have excellent electrical properties at a maximum mechanical strain of 3400% (resistance change <0.27%) with a helical index of 11. Moreover, the conductive fibers can be welded to various two or three-dimensional conductors. In summary, with a scalable manufacturing process, weldability, superelasticity, and high electrical conductivity, EGaIn/TPU composite fibers fabricated by wet spinning have considerable potential for flexible electronics.
Collapse
Affiliation(s)
- Jingyu Zhou
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Shanshan Zhao
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Lei Tang
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Dawei Zhang
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Bin Sheng
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| |
Collapse
|
7
|
Zhou J, Fu C, Fang J, Shang K, Pu X, Zhang Y, Jiang Z, Lu X, He C, Jia L, Yao Y, Qian L, Yang T. Prosthetic finger for fingertip tactile sensing via flexible chromatic optical waveguides. MATERIALS HORIZONS 2023; 10:4940-4951. [PMID: 37609940 DOI: 10.1039/d3mh00921a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Building prosthetics indistinguishable from human limbs to accurately receive and transmit sensory information to users not only promises to radically improve the lives of amputees, but also shows potential in a range of robotic applications. Currently, a mainstream approach is to embed electrical or optical sensors with force/thermal sensing functions on the surface or inside of prosthetic fingers. Compared with electrical sensing technologies, tactile sensors based on stretchable optical waveguides have the advantages of easy fabrication, chemical safety, environmental stability, and compatibility with prosthetic structural materials. However, so far, research has mainly focused on the perception of finger joint motion or external press, and there is still a lack of study on optical sensors with fingertip tactile capabilities (such as texture, hardness, slip detection, etc.). Here we report a 3D printing prosthetic finger with flexible chromatic optical waveguides implanted at the fingertip. The finger achieves distributed displacement/force sensing detection, and exhibits high sensitivity, fast response and good stability. The finger can be used to conduct active sensory experiments, and the detection parameters include object contour, hardness, slip direction and speed, temperature, etc. Finally, exploratory research on identifying and manipulating objects is carried out with this finger. The developed prosthetic finger can artificially recreate touch perception and realize complex functions such as note-writing analysis and braille recognition.
Collapse
Affiliation(s)
- Jian Zhou
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| | - Chunqiao Fu
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| | - Jiahao Fang
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| | - Kedong Shang
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| | - Xiaobo Pu
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
- China Railway Academy CO., LTD., Chengdu 610031, P. R. China
| | - Yong Zhang
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| | - Zhongbao Jiang
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| | - Xulei Lu
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| | - Changliu He
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| | - Lingxu Jia
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| | - Yuming Yao
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| | - Linmao Qian
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| | - Tingting Yang
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, P. R. China.
| |
Collapse
|
8
|
Idil N, Aslıyüce S, Perçin I, Mattiasson B. Recent Advances in Optical Sensing for the Detection of Microbial Contaminants. MICROMACHINES 2023; 14:1668. [PMID: 37763831 PMCID: PMC10536746 DOI: 10.3390/mi14091668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 08/14/2023] [Accepted: 08/19/2023] [Indexed: 09/29/2023]
Abstract
Microbial contaminants are responsible for several infectious diseases, and they have been introduced as important potential food- and water-borne risk factors. They become a global burden due to their health and safety threats. In addition, their tendency to undergo mutations that result in antimicrobial resistance makes them difficult to treat. In this respect, rapid and reliable detection of microbial contaminants carries great significance, and this research area is explored as a rich subject within a dynamic state. Optical sensing serving as analytical devices enables simple usage, low-cost, rapid, and sensitive detection with the advantage of their miniaturization. From the point of view of microbial contaminants, on-site detection plays a crucial role, and portable, easy-applicable, and effective point-of-care (POC) devices offer high specificity and sensitivity. They serve as advanced on-site detection tools and are pioneers in next-generation sensing platforms. In this review, recent trends and advances in optical sensing to detect microbial contaminants were mainly discussed. The most innovative and popular optical sensing approaches were highlighted, and different optical sensing methodologies were explained by emphasizing their advantages and limitations. Consequently, the challenges and future perspectives were considered.
Collapse
Affiliation(s)
- Neslihan Idil
- Department of Biology, Biotechnology Division, Hacettepe University, Ankara 06800, Turkey;
| | - Sevgi Aslıyüce
- Department of Chemistry, Biochemistry Division, Hacettepe University, Ankara 06800, Turkey;
| | - Işık Perçin
- Department of Biology, Molecular Biology Division, Hacettepe University, Ankara 06800, Turkey;
| | - Bo Mattiasson
- Department of Biotechnology, Lund University, 22100 Lund, Sweden
- Indienz AB, Annebergs Gård, 26873 Billeberga, Sweden
| |
Collapse
|
9
|
Li J, Chen S, Zhou J, Tang L, Jiang C, Zhang D, Sheng B. Flexible BaTiO 3-PDMS Capacitive Pressure Sensor of High Sensitivity with Gradient Micro-Structure by Laser Engraving and Molding. Polymers (Basel) 2023; 15:3292. [PMID: 37571185 PMCID: PMC10422564 DOI: 10.3390/polym15153292] [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: 07/17/2023] [Revised: 07/30/2023] [Accepted: 08/02/2023] [Indexed: 08/13/2023] Open
Abstract
The significant potential of flexible sensors in various fields such as human health, soft robotics, human-machine interaction, and electronic skin has garnered considerable attention. Capacitive pressure sensor is popular given their mechanical flexibility, high sensitivity, and signal stability. Enhancing the performance of capacitive sensors can be achieved through the utilization of gradient structures and high dielectric constant media. This study introduced a novel dielectric layer, employing the BaTiO3-PDMS material with a gradient micro-cones architecture (GMCA). The capacitive sensor was constructed by incorporating a dielectric layer GMCA, which was fabricated using laser engraved acrylic (PMMA) molds and flexible copper-foil/polyimide-tape electrodes. To examine its functionality, the prepared sensor was subjected to a pressure range of 0-50 KPa. Consequently, this sensor exhibited a remarkable sensitivity of up to 1.69 KPa-1 within the pressure range of 0-50 KPa, while maintaining high pressure-resolution across the entire pressure spectrum. Additionally, the pressure sensor demonstrated a rapid response time of 50 ms, low hysteresis of 0.81%, recovery time of 160 ms, and excellent cycling stability over 1000 cycles. The findings indicated that the GMCA pressure sensor, which utilized a gradient structure and BaTiO3-PDMS material, exhibited notable sensitivity and a broad linear pressure range. These results underscore the adaptability and viability of this technology, thereby facilitating enhanced flexibility in pressure sensors and fostering advancements in laser manufacturing and flexible devices for a wider array of potential applications.
Collapse
Affiliation(s)
- Jiayi Li
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (J.L.); (J.Z.); (L.T.); (C.J.); (D.Z.)
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Shangbi Chen
- Inertial Technology Division, Shanghai Aerospace Control Technology Institute, Shanghai 201109, China;
| | - Jingyu Zhou
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (J.L.); (J.Z.); (L.T.); (C.J.); (D.Z.)
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Lei Tang
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (J.L.); (J.Z.); (L.T.); (C.J.); (D.Z.)
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Chenkai Jiang
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (J.L.); (J.Z.); (L.T.); (C.J.); (D.Z.)
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Dawei Zhang
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (J.L.); (J.Z.); (L.T.); (C.J.); (D.Z.)
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Bin Sheng
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (J.L.); (J.Z.); (L.T.); (C.J.); (D.Z.)
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| |
Collapse
|
10
|
Qu C, Lu M, Zhang Z, Chen S, Liu D, Zhang D, Wang J, Sheng B. Flexible Microstructured Capacitive Pressure Sensors Using Laser Engraving and Graphitization from Natural Wood. Molecules 2023; 28:5339. [PMID: 37513212 PMCID: PMC10385064 DOI: 10.3390/molecules28145339] [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: 05/18/2023] [Revised: 06/28/2023] [Accepted: 07/01/2023] [Indexed: 07/30/2023] Open
Abstract
In recent years, laser engraving has received widespread attention as a convenient, efficient, and programmable method which has enabled high-quality porous graphene to be obtained from various precursors. Laser engraving is often used to fabricate the dielectric layer with a microstructure for capacitive pressure sensors; however, the usual choice of electrodes remains poorly flexible metal electrodes, which greatly limit the overall flexibility of the sensors. In this work, we propose a flexible capacitive pressure sensor made entirely of thermoplastic polyurethane (TPU) and laser-induced graphene (LIG) derived from wood. The capacitive pressure sensor consisted of a flexible LIG/TPU electrode (LTE), an LIG/TPU electrode with a microhole array, and a dielectric layer of TPU with microcone array molded from a laser-engraved hole array on wood, which provided high sensitivity (0.11 kPa-1), an ultrawide pressure detection range (20 Pa to 1.4 MPa), a fast response (~300 ms), and good stability (>4000 cycles, at 0-35 kPa). We believe that our research makes a significant contribution to the literature, because the easy availability of the materials derived from wood and the overall consistent flexibility meet the requirements of flexible electronic devices.
Collapse
Affiliation(s)
- Chenkai Qu
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Meilan Lu
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Ziyan Zhang
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Shangbi Chen
- Inertial Technology Division, Shanghai Aerospace Control Technology Institute, Shanghai 201109, China
| | - Dewen Liu
- Inertial Technology Division, Shanghai Aerospace Control Technology Institute, Shanghai 201109, China
| | - Dawei Zhang
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Jing Wang
- Department of Ultrasound Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310006, China
| | - Bin Sheng
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| |
Collapse
|
11
|
Zhang Y, Lu H, Zhang M, Hou Z, Li S, Wang H, Wu XE, Zhang Y. In Situ Mineralizing Spinning of Strong and Tough Silk Fibers for Optical Waveguides. ACS NANO 2023; 17:5905-5912. [PMID: 36892421 DOI: 10.1021/acsnano.2c12855] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Biopolymer-based optical waveguides with low-loss light guiding performance and good biocompatibility are highly desired for applications in biomedical photonic devices. Herein, we report the preparation of silk optical fiber waveguides through bioinspired in situ mineralizing spinning, which possess excellent mechanical properties and low light loss. Natural silk fibroin was used as the main precursor for the wet spinning of the regenerated silk fibroin (RSF) fibers. Calcium carbonate nanocrystals (CaCO3 NCs) were in situ grown in the RSF network and served as nucleation templates for mineralization during the spinning, leading to the formation of strong and tough fibers. CaCO3 NCs can guide the structure transformation of silk fibroin from random coils to β-sheets, contributing to enhanced mechanical properties. The tensile strength and toughness of the obtained fibers are up to 0.83 ± 0.15 GPa and 181.98 ± 52.42 MJ·m-3, obviously higher than those of natural silkworm silks and even comparable to spider silks. We further investigated the performance of the fibers as optical waveguides and observed a low light loss of 0.46 dB·cm-1, which is much lower than natural silk fibers. We believed that these silk-based fibers with excellent mechanical and light propagation properties are promising for applications in biomedical light imaging and therapy.
Collapse
Affiliation(s)
- Yong Zhang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
- Department of Equipment Maintenance and Remanufacturing Engineering, Academy of Army Armored Forces, Beijing, 100072, China
| | - Haojie Lu
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Mingchao Zhang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Zhishan Hou
- Department of Precision Instrument, Tsinghua University, Beijing, 100084, China
| | - Shuo Li
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Haomin Wang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Xun-En Wu
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yingying Zhang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| |
Collapse
|
12
|
Li Y, Yu J, Wei Y, Wang Y, Feng Z, Cheng L, Huo Z, Lei Y, Sun Q. Recent Progress in Self-Powered Wireless Sensors and Systems Based on TENG. SENSORS (BASEL, SWITZERLAND) 2023; 23:s23031329. [PMID: 36772369 PMCID: PMC9921943 DOI: 10.3390/s23031329] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/14/2023] [Accepted: 01/18/2023] [Indexed: 06/12/2023]
Abstract
With the development of 5G, artificial intelligence, and the Internet of Things, diversified sensors (such as the signal acquisition module) have become more and more important in people's daily life. According to the extensive use of various distributed wireless sensors, powering them has become a big problem. Among all the powering methods, the self-powered sensor system based on triboelectric nanogenerators (TENGs) has shown its superiority. This review focuses on four major application areas of wireless sensors based on TENG, including environmental monitoring, human monitoring, industrial production, and daily life. The perspectives and outlook of the future development of self-powered wireless sensors are discussed.
Collapse
Affiliation(s)
- Yonghai Li
- Center on Nanoenergy Research, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, China
| | - Jinran Yu
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yichen Wei
- Center on Nanoenergy Research, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, China
| | - Yifei Wang
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhenyu Feng
- Center on Nanoenergy Research, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, China
| | - Liuqi Cheng
- Center on Nanoenergy Research, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, China
| | - Ziwei Huo
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanqiang Lei
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qijun Sun
- Center on Nanoenergy Research, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, China
- School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
13
|
Yu H, Zheng D, Liu Y, Chen S, Wang X, Peng W. Data Glove with Self-Compensation Mechanism Based on High-Sensitive Elastic Fiber-Optic Sensor. Polymers (Basel) 2022; 15:polym15010100. [PMID: 36616450 PMCID: PMC9824815 DOI: 10.3390/polym15010100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/12/2022] [Accepted: 12/12/2022] [Indexed: 12/28/2022] Open
Abstract
With the development of virtual reality (VR) interaction technology, data glove has become one of the most popular devices for human-computer interaction. It's valuable to design high-sensitive and flexible sensor for data glove. Therefore, a low-cost data glove based on self-compensating elastic optical fiber sensor with self-calibration function is proposed. The tunable and stretchable elastic fiber was fabricated by a simple, economical and controllable method. The fiber has good flexibility and high stability under stretching, bending and indentation deformation. The optical fibers are installed in the sensor in a U shape with a bending radius of 5 mm. Compared with the straight fiber, the response sensitivity of the U-shaped fiber to deformation is increased by about 7 times at most. The reference optical fiber is connected to the sensor, which effectively improves the stability and accuracy of the sensor system. In addition, the sensors are easy to install so that the data gloves can be customized for different hand shapes. In the gesture capture test, it can respond quickly and guide the manipulator to track the gesture. This responsive and stable data glove has broad development potential in motion monitoring, telemedicine and human-computer interaction.
Collapse
Affiliation(s)
- Hui Yu
- School of Physics, Dalian University of Technology, Dalian116024, China
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian 116024, China
| | - Daifu Zheng
- School of Physics, Dalian University of Technology, Dalian116024, China
| | - Yun Liu
- School of Physics, Dalian University of Technology, Dalian116024, China
- Correspondence: (Y.L.); (X.W.)
| | - Shimeng Chen
- Marine Engineering College, Dalian Maritime University, Dalian 116026, China
| | - Xiaona Wang
- School of Physics, Dalian University of Technology, Dalian116024, China
- Correspondence: (Y.L.); (X.W.)
| | - Wei Peng
- School of Physics, Dalian University of Technology, Dalian116024, China
| |
Collapse
|
14
|
Shi S, Liang J, Qu C, Chen S, Sheng B. Ramie Fabric Treated with Carboxymethylcellulose and Laser Engraved for Strain and Humidity Sensing. MICROMACHINES 2022; 13:mi13081309. [PMID: 36014231 PMCID: PMC9414723 DOI: 10.3390/mi13081309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/11/2022] [Accepted: 08/11/2022] [Indexed: 05/08/2023]
Abstract
Wearable fabric sensors have attracted enormous attention due to their huge potential in human health and activity monitoring, human-machine interaction and the Internet of Things (IoT). Among natural fabrics, bast fabric has the advantage of high strength, good resilience and excellent permeability. Laser engraving, as a high throughput, patternable and mask-free method, was demonstrated to fabricate fabric sensors. In this work, we developed a simplified, cost-effective and environmentally friendly method for engraving ramie fabric (a kind of bast fabric) directly by laser under an ambient atmosphere to prepare strain and humidity sensors. We used carboxymethylcellulose (CMC) to pretreat ramie fabric before laser engraving and gained laser-carbonized ramie fabrics (LCRF) with high conductivity (65 Ω sq-1) and good permeability. The strain and humidity sensors had high sensitivity and good flexibility, which can be used for human health and activity monitoring.
Collapse
Affiliation(s)
- Shangxuan Shi
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Jiao Liang
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Chenkai Qu
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
| | - Shangbi Chen
- Shanghai Aerospace Control Technology Institute, Shanghai 200233, China
| | - Bin Sheng
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Shanghai Key Laboratory of Modern Optical Systems, Engineering Research Center of Optical Instruments and Systems, Shanghai 200093, China
- Correspondence:
| |
Collapse
|
15
|
Babu VJ, Anusha M, Sireesha M, Sundarrajan S, Abdul Haroon Rashid SSA, Kumar AS, Ramakrishna S. Intelligent Nanomaterials for Wearable and Stretchable Strain Sensor Applications: The Science behind Diverse Mechanisms, Fabrication Methods, and Real-Time Healthcare. Polymers (Basel) 2022; 14:polym14112219. [PMID: 35683893 PMCID: PMC9182624 DOI: 10.3390/polym14112219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 05/24/2022] [Accepted: 05/27/2022] [Indexed: 11/30/2022] Open
Abstract
It has become a scientific obligation to unveil the underlying mechanisms and the fabrication methods behind wearable/stretchable strain sensors based on intelligent nanomaterials in order to explore their possible potential in the field of biomedical and healthcare applications. This report is based on an extensive literature survey of fabrication of stretchable strain sensors (SSS) based on nanomaterials in the fields of healthcare, sports, and entertainment. Although the evolution of wearable strain sensors (WSS) is rapidly progressing, it is still at a prototype phase and various challenges need to be addressed in the future in special regard to their fabrication protocols. The biocalamity of COVID-19 has brought a drastic change in humans’ lifestyles and has negatively affected nations in all capacities. Social distancing has become a mandatory rule to practice in common places where humans interact with each other as a basic need. As social distancing cannot be ruled out as a measure to stop the spread of COVID-19 virus, wearable sensors could play a significant role in technologically impacting people’s consciousness. This review article meticulously describes the role of wearable and strain sensors in achieving such objectives.
Collapse
Affiliation(s)
- Veluru Jagadeesh Babu
- NUS Centre for Nanotechnology and Sustainability, Department of Mechanical Engineering, National University of Singapore, Singapore 117581, Singapore; (M.S.); (S.S.A.A.H.R.); (S.R.)
- Correspondence: (V.J.B.); (S.S.)
| | - Merum Anusha
- Department of Pharmacology, S V Medical College, Dr NTR University of Health Sciences, Vijayawada 517501, India;
| | - Merum Sireesha
- NUS Centre for Nanotechnology and Sustainability, Department of Mechanical Engineering, National University of Singapore, Singapore 117581, Singapore; (M.S.); (S.S.A.A.H.R.); (S.R.)
| | - Subramanian Sundarrajan
- NUS Centre for Nanotechnology and Sustainability, Department of Mechanical Engineering, National University of Singapore, Singapore 117581, Singapore; (M.S.); (S.S.A.A.H.R.); (S.R.)
- Correspondence: (V.J.B.); (S.S.)
| | - Syed Sulthan Alaudeen Abdul Haroon Rashid
- NUS Centre for Nanotechnology and Sustainability, Department of Mechanical Engineering, National University of Singapore, Singapore 117581, Singapore; (M.S.); (S.S.A.A.H.R.); (S.R.)
- Centre for Advanced Materials and Industrial Chemistry (CAMIC), School of Science, RMIT University, Melbourne, VIC 3001, Australia
| | - A. Senthil Kumar
- Advanced Manufacturing Laboratory, Department of Mechanical Engineering, National University of Singapore, Singapore 117581, Singapore;
| | - Seeram Ramakrishna
- NUS Centre for Nanotechnology and Sustainability, Department of Mechanical Engineering, National University of Singapore, Singapore 117581, Singapore; (M.S.); (S.S.A.A.H.R.); (S.R.)
| |
Collapse
|
16
|
Wang J, Wang L, Su X, Xiao R, Cheng H. Polarization Maintaining Fiber Temperature and Stress Gradient Sensitization Sensor Based on Semiconductor-Metal-Polymer Three-Layer Film Coating. ACS APPLIED MATERIALS & INTERFACES 2022; 14:20053-20061. [PMID: 35438503 DOI: 10.1021/acsami.2c03102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Increasing sensitivity, measuring points, and stability have always been the pursuit of sensors. ZnSe9:CO1 and Ag composite nano films were coated on polarization maintaining fiber (PMF). Then, the coated PMF was nested in capillary and hose which was encapsulated with polydimethylsiloxane (PDMS) and epoxy resin. The integrated capillary sensor and thermoplastic hose sensor were prepared. The gradient sensitization of various measurement parameters such as temperature, stress, and micro bending is realized. The temperature sensitivity is 1.49 nm/°C, the micro bending sensitivity is 1.72 nm/102 g, and the stress sensitivity is 6.27 nm/mε. The sensors maintain good linearity and instantaneous response while having high sensitivity. By adjusting the length of PMF, the number of troughs is increased in the same band range, and different troughs have different sensitivities, which solves the inherent problem of cross sensitivity and realizes multiparameter measurement. Capillary sensors are used for remote safe real-time monitoring of mechanical overheating, and hose sensors are used for real-time monitoring of bridge load and human joint bending. This work is of great significance to the extension of the application range of optical fiber sensor.
Collapse
Affiliation(s)
- Jin Wang
- College of Physics and Optoelectronics, Faculty of Science, Beijing University of Technology, Beijing 100124, China
| | - Li Wang
- College of Physics and Optoelectronics, Faculty of Science, Beijing University of Technology, Beijing 100124, China
| | - XueQiong Su
- College of Physics and Optoelectronics, Faculty of Science, Beijing University of Technology, Beijing 100124, China
| | - RanRan Xiao
- College of Physics and Optoelectronics, Faculty of Science, Beijing University of Technology, Beijing 100124, China
| | - Hao Cheng
- College of Physics and Optoelectronics, Faculty of Science, Beijing University of Technology, Beijing 100124, China
| |
Collapse
|
17
|
Meng K, Xiao X, Wei W, Chen G, Nashalian A, Shen S, Xiao X, Chen J. Wearable Pressure Sensors for Pulse Wave Monitoring. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2109357. [PMID: 35044014 DOI: 10.1002/adma.202109357] [Citation(s) in RCA: 142] [Impact Index Per Article: 71.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/21/2021] [Indexed: 05/15/2023]
Abstract
Cardiovascular diseases remain the leading cause of death worldwide. The rapid development of flexible sensing technologies and wearable pressure sensors have attracted keen research interest and have been widely used for long-term and real-time cardiovascular status monitoring. Owing to compelling characteristics, including light weight, wearing comfort, and high sensitivity to pulse pressures, physiological pulse waveforms can be precisely and continuously monitored by flexible pressure sensors for wearable health monitoring. Herein, an overview of wearable pressure sensors for human pulse wave monitoring is presented, with a focus on the transduction mechanism, microengineering structures, and related applications in pulse wave monitoring and cardiovascular condition assessment. The conceptualizations and methods for the acquisition of physiological and pathological information related to the cardiovascular system are outlined. The biomechanics of arterial pulse waves and the working mechanism of various wearable pressure sensors, including triboelectric, piezoelectric, magnetoelastic, piezoresistive, capacitive, and optical sensors, are also subject to systematic debate. Exemple applications of pulse wave measurement based on microengineering structured devices are then summarized. Finally, a discussion of the opportunities and challenges that wearable pressure sensors face, as well as their potential as a wearable intelligent system for personalized healthcare is given in conclusion.
Collapse
Affiliation(s)
- Keyu Meng
- School of Electronic and Information Engineering Jilin Provincial Key Laboratory of Human Health Status Identification and Function Enhancement, Changchun University, Changchun, 130022, China
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California, 90095, USA
| | - Xiao Xiao
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California, 90095, USA
| | - Wenxin Wei
- Department of Anesthesiology, China Medical University, Shenyang, 110022, China
| | - Guorui Chen
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California, 90095, USA
| | - Ardo Nashalian
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California, 90095, USA
| | - Sophia Shen
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California, 90095, USA
| | - Xiao Xiao
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California, 90095, USA
| | - Jun Chen
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California, 90095, USA
| |
Collapse
|
18
|
Li T, Su Y, Chen F, Liao X, Wu Q, Kang Y, Tan Y, Zhou Z. A Skin‐Like and Highly Stretchable Optical Fiber Sensor with the Hybrid Coding of Wavelength–Light Intensity. ADVANCED INTELLIGENT SYSTEMS 2021. [DOI: 10.1002/aisy.202100193] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Tianliang Li
- School of Mechanical and Electronic Engineering Wuhan University of Technology Wuhan 430070 China
| | - Yifei Su
- School of Mechanical and Electronic Engineering Wuhan University of Technology Wuhan 430070 China
| | - Fayin Chen
- School of Mechanical and Electronic Engineering Wuhan University of Technology Wuhan 430070 China
| | - Xinqin Liao
- School of Electronic Science and Engineering Xiamen University 422 Siming South Road Xiamen 361005 China
- School of Electrical and Electronic Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Singapore
| | - Qin Wu
- Department of Critical Care Medicine, West China Hospital Sichuan University No. 37 Guo Xue Alley, Wuhou District Chengdu Sichuan 610041 China
| | - Yan Kang
- Department of Critical Care Medicine, West China Hospital Sichuan University No. 37 Guo Xue Alley, Wuhou District Chengdu Sichuan 610041 China
| | - Yuegang Tan
- School of Mechanical and Electronic Engineering Wuhan University of Technology Wuhan 430070 China
| | - Zude Zhou
- School of Mechanical and Electronic Engineering Wuhan University of Technology Wuhan 430070 China
| |
Collapse
|
19
|
Xiang S, You H, Miao X, Niu L, Yao C, Jiang Y, Zhou G. An Ultra-Sensitive Multi-Functional Optical Micro/Nanofiber Based on Stretchable Encapsulation. SENSORS (BASEL, SWITZERLAND) 2021; 21:7437. [PMID: 34833512 PMCID: PMC8618424 DOI: 10.3390/s21227437] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 10/28/2021] [Accepted: 11/03/2021] [Indexed: 01/30/2023]
Abstract
Stretchable optical fiber sensors (SOFSs), which are promising and ultra-sensitive next-generation sensors, have achieved prominent success in applications including health monitoring, robotics, and biological-electronic interfaces. Here, we report an ultra-sensitive multi-functional optical micro/nanofiber embedded with a flexible polydimethylsiloxane (PDMS) membrane, which is compatible with wearable optical sensors. Based on the effect of a strong evanescent field, the as-fabricated SOFS is highly sensitive to strain, achieving high sensitivity with a peak gauge factor of 450. In addition, considering the large negative thermo-optic coefficient of PDMS, temperature measurements in the range of 30 to 60 °C were realized, resulting in a 0.02 dBm/°C response. In addition, wide-range detection of humidity was demonstrated by a peak sensitivity of 0.5 dB/% RH, with less than 10% variation at each humidity stage. The robust sensing performance, together with the flexibility, enables the real-time monitoring of pulse, body temperature, and respiration. This as-fabricated SOFS provides significant potential for the practical application of wearable healthcare sensors.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Guorui Zhou
- Department of Engineering Optics, Research Center of Laser Fusion CAEP, Mianyang 621900, China; (S.X.); (H.Y.); (X.M.); (L.N.); (C.Y.); (Y.J.)
| |
Collapse
|
20
|
Li DJ, Li QH, Wang ZR, Ma ZZ, Gu ZG, Zhang J. Interpenetrated Metal-Porphyrinic Framework for Enhanced Nonlinear Optical Limiting. J Am Chem Soc 2021; 143:17162-17169. [PMID: 34543015 DOI: 10.1021/jacs.1c07803] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Structural interpenetration in metal-organic frameworks (MOFs) significantly impacts on their properties and functionalities. However, understanding the interpenetration on third-order nonlinear optics (NLO) of MOFs have not been reported to date. Herein, we report two 3D porphyrinic MOFs, a 2-fold interpenetrated [Zn2(TPyP)(AC)2] (ZnTPyP-1) and a noninterpenetrated [Zn3(TPyP)(H2O)2(C2O4)2] (ZnTPyP-2), constructed from 5,10,15,20-tetra(4-pyridyl)porphyrin (TPyP(H2)) and Zn(NO3)2 (AC = acetate, C2O4 = oxalate). ZnTPyP-1 achieves excellent optical limiting (OL) performance with a giant nonlinear absorption coefficient (3.61 × 106 cm/GW) and large third-order susceptibility (7.73 × 10-7 esu), which is much better than ZnTPyP-2 and other reported OL materials. The corresponding MOFs nanosheets are dispersed into a polydimethylsiloxane (PDMS) matrix to form highly transparent and flexible MOFs/PDMS glasses for practical OL application. In addition, the OL response optimized by adjusting the MOFs concentration in the PDMS matrix and the type of metalloporphyrin are discussed in the ZnTPyP-1 system. The theoretical calculation confirmed that the abundant π-π interaction from porphyrinic groups in the interpenetrated framework increased the electron delocalization/transfer and boosted the OL performance. This study opens a new avenue to enhance OL performance by the construction of interpenetrated structures and provides a new approach for the preparation of transparent and flexible MOF composites in nonlinear optical applications.
Collapse
Affiliation(s)
- De-Jing Li
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China.,Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou, Fujian 350108, P. R. China
| | - Qiao-Hong Li
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China
| | - Zi-Rui Wang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China
| | - Zhi-Zhou Ma
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China
| | - Zhi-Gang Gu
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China.,Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou, Fujian 350108, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jian Zhang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China.,Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou, Fujian 350108, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| |
Collapse
|
21
|
Bunea AC, Dediu V, Laszlo EA, Pistriţu F, Carp M, Iliescu FS, Ionescu ON, Iliescu C. E-Skin: The Dawn of a New Era of On-Body Monitoring Systems. MICROMACHINES 2021; 12:1091. [PMID: 34577734 PMCID: PMC8470991 DOI: 10.3390/mi12091091] [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: 08/13/2021] [Revised: 09/01/2021] [Accepted: 09/08/2021] [Indexed: 12/13/2022]
Abstract
Real-time "on-body" monitoring of human physiological signals through wearable systems developed on flexible substrates (e-skin) is the next target in human health control and prevention, while an alternative to bulky diagnostic devices routinely used in clinics. The present work summarizes the recent trends in the development of e-skin systems. Firstly, we revised the material development for e-skin systems. Secondly, aspects related to fabrication techniques were presented. Next, the main applications of e-skin systems in monitoring, such as temperature, pulse, and other bio-electric signals related to health status, were analyzed. Finally, aspects regarding the power supply and signal processing were discussed. The special features of e-skin as identified contribute clearly to the developing potential as in situ diagnostic tool for further implementation in clinical practice at patient personal levels.
Collapse
Affiliation(s)
- Alina-Cristina Bunea
- National Institute for Research and Development in Microtechnologies—IMT, 077190 Bucharest, Romania; (A.-C.B.); (V.D.); (E.A.L.); (F.P.); (M.C.); (F.S.I.); (O.N.I.)
| | - Violeta Dediu
- National Institute for Research and Development in Microtechnologies—IMT, 077190 Bucharest, Romania; (A.-C.B.); (V.D.); (E.A.L.); (F.P.); (M.C.); (F.S.I.); (O.N.I.)
| | - Edwin Alexandru Laszlo
- National Institute for Research and Development in Microtechnologies—IMT, 077190 Bucharest, Romania; (A.-C.B.); (V.D.); (E.A.L.); (F.P.); (M.C.); (F.S.I.); (O.N.I.)
| | - Florian Pistriţu
- National Institute for Research and Development in Microtechnologies—IMT, 077190 Bucharest, Romania; (A.-C.B.); (V.D.); (E.A.L.); (F.P.); (M.C.); (F.S.I.); (O.N.I.)
| | - Mihaela Carp
- National Institute for Research and Development in Microtechnologies—IMT, 077190 Bucharest, Romania; (A.-C.B.); (V.D.); (E.A.L.); (F.P.); (M.C.); (F.S.I.); (O.N.I.)
| | - Florina Silvia Iliescu
- National Institute for Research and Development in Microtechnologies—IMT, 077190 Bucharest, Romania; (A.-C.B.); (V.D.); (E.A.L.); (F.P.); (M.C.); (F.S.I.); (O.N.I.)
| | - Octavian Narcis Ionescu
- National Institute for Research and Development in Microtechnologies—IMT, 077190 Bucharest, Romania; (A.-C.B.); (V.D.); (E.A.L.); (F.P.); (M.C.); (F.S.I.); (O.N.I.)
- Faculty of Electrical and Mechanical Engineering, Petroleum-Gas University of Ploiesti, 100680 Ploiesti, Romania
| | - Ciprian Iliescu
- National Institute for Research and Development in Microtechnologies—IMT, 077190 Bucharest, Romania; (A.-C.B.); (V.D.); (E.A.L.); (F.P.); (M.C.); (F.S.I.); (O.N.I.)
- Academy of Romanian Scientists, 010071 Bucharest, Romania
- Faculty of Applied Chemistry and Materials Science, University “Politehnica” of Bucharest, 011061 Bucharest, Romania
| |
Collapse
|
22
|
Wu C, Liu X, Ying Y. Soft and Stretchable Optical Waveguide: Light Delivery and Manipulation at Complex Biointerfaces Creating Unique Windows for On-Body Sensing. ACS Sens 2021; 6:1446-1460. [PMID: 33611914 DOI: 10.1021/acssensors.0c02566] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Over the past few decades, optical waveguides have been increasingly used in wearable/implantable devices for on-body sensing. However, conventional optical waveguides are stiff, rigid, and brittle. A mismatch between conventional optical waveguides and complex biointerfaces makes wearable/implantable devices uncomfortable to wear and potentially unsafe. Soft and stretchable polymer optical waveguides not only inherit many advantages of conventional optical waveguides (e.g., immunity to electromagnetic interference and without electrical hazards) but also provide a new perspective for solving the mismatch between conventional optical waveguides and complex biointerfaces, which is essential for the development of light-based wearable/implantable sensors. In this review, polymer optical waveguides' unique properties, including flexibility, biocompatibility and biodegradability, porosity, and stimulus responsiveness, and their applications in the wearable/implantable field in recent years are summarized. Then, we briefly discuss the current challenges of high optical loss, unstable signal transmission, low manufacturing efficiency, and difficulty in deployment during implantation of flexible polymer optical waveguides, and propose some possible solutions to these problems.
Collapse
Affiliation(s)
- Chenjian Wu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, China
| | - Xiangjiang Liu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, China
- College of Mechanical and Electrical Engineering, Xinjiang Agricultural University, Urumqi, 830052, China
| | - Yibin Ying
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, China
| |
Collapse
|
23
|
Vandekerckhove B, Missinne J, Vonck K, Bauwens P, Verplancke R, Boon P, Raedt R, Vanfleteren J. Technological Challenges in the Development of Optogenetic Closed-Loop Therapy Approaches in Epilepsy and Related Network Disorders of the Brain. MICROMACHINES 2020; 12:38. [PMID: 33396287 PMCID: PMC7824489 DOI: 10.3390/mi12010038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 12/24/2020] [Accepted: 12/28/2020] [Indexed: 12/25/2022]
Abstract
Epilepsy is a chronic, neurological disorder affecting millions of people every year. The current available pharmacological and surgical treatments are lacking in overall efficacy and cause side-effects like cognitive impairment, depression, tremor, abnormal liver and kidney function. In recent years, the application of optogenetic implants have shown promise to target aberrant neuronal circuits in epilepsy with the advantage of both high spatial and temporal resolution and high cell-specificity, a feature that could tackle both the efficacy and side-effect problems in epilepsy treatment. Optrodes consist of electrodes to record local field potentials and an optical component to modulate neurons via activation of opsin expressed by these neurons. The goal of optogenetics in epilepsy is to interrupt seizure activity in its earliest state, providing a so-called closed-loop therapeutic intervention. The chronic implantation in vivo poses specific demands for the engineering of therapeutic optrodes. Enzymatic degradation and glial encapsulation of implants may compromise long-term recording and sufficient illumination of the opsin-expressing neural tissue. Engineering efforts for optimal optrode design have to be directed towards limitation of the foreign body reaction by reducing the implant's elastic modulus and overall size, while still providing stable long-term recording and large-area illumination, and guaranteeing successful intracerebral implantation. This paper presents an overview of the challenges and recent advances in the field of electrode design, neural-tissue illumination, and neural-probe implantation, with the goal of identifying a suitable candidate to be incorporated in a therapeutic approach for long-term treatment of epilepsy patients.
Collapse
Affiliation(s)
- Bram Vandekerckhove
- Center for Microsystems Technology, Imec and Ghent University, 9000 Ghent, Belgium; (B.V.); (J.M.); (P.B.); (R.V.)
| | - Jeroen Missinne
- Center for Microsystems Technology, Imec and Ghent University, 9000 Ghent, Belgium; (B.V.); (J.M.); (P.B.); (R.V.)
| | - Kristl Vonck
- 4Brain Team, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (K.V.); (P.B.); (R.R.)
| | - Pieter Bauwens
- Center for Microsystems Technology, Imec and Ghent University, 9000 Ghent, Belgium; (B.V.); (J.M.); (P.B.); (R.V.)
| | - Rik Verplancke
- Center for Microsystems Technology, Imec and Ghent University, 9000 Ghent, Belgium; (B.V.); (J.M.); (P.B.); (R.V.)
| | - Paul Boon
- 4Brain Team, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (K.V.); (P.B.); (R.R.)
| | - Robrecht Raedt
- 4Brain Team, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (K.V.); (P.B.); (R.R.)
| | - Jan Vanfleteren
- Center for Microsystems Technology, Imec and Ghent University, 9000 Ghent, Belgium; (B.V.); (J.M.); (P.B.); (R.V.)
| |
Collapse
|
24
|
Hu X, Yang K, Zhang C. Optimization of Preparation Conditions for Side-Emitting Polymer Optical Fibers Using Response Surface Methodology. Polymers (Basel) 2020; 12:E3062. [PMID: 33371300 PMCID: PMC7766554 DOI: 10.3390/polym12123062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 12/15/2020] [Accepted: 12/17/2020] [Indexed: 12/30/2022] Open
Abstract
Polymer optical fibers (POFs) were used for preparing side-emitting polymer optical fibers (SPOFs), which were processed with acetone and n-hexane combined in selected proportions by a solvent treatment method. The effects of the volume ratio of acetone to n-hexane and treatment time on response variable factors were investigated. The center composite design (CCD) based response surface methodology (RSM), a quadratic model, and a two-factor interaction model were developed to relate the preparation variables of illumination intensity, breaking strength, and rigidity. According to analysis of variance (ANOVA), the factors affecting the optimization of each response factor were determined. The predicted values after process optimization were found to be highly similar to the experimental values. The optimal conditions for the preparation of SPOF were as follows: the volume ratio of acetone to hexane was 1.703, and the treatment time was 2.716 s. The three response variables of SPOF prepared under the optimal conditions were: illumination intensity 19.339 mV, breaking strength 5.707 N, and rigidity 572.013 N·mm2.
Collapse
Affiliation(s)
- Xianjin Hu
- School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China;
| | - Kun Yang
- School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China;
| | - Cheng Zhang
- School of Electrical Engineering and Automation, Tiangong University, Tianjin 300387, China;
| |
Collapse
|
25
|
Peng Z, Chen X, Fan Y, Srolovitz DJ, Lei D. Strain engineering of 2D semiconductors and graphene: from strain fields to band-structure tuning and photonic applications. LIGHT, SCIENCE & APPLICATIONS 2020; 9:190. [PMID: 33298826 PMCID: PMC7680797 DOI: 10.1038/s41377-020-00421-5] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 10/10/2020] [Accepted: 10/14/2020] [Indexed: 05/05/2023]
Abstract
Two-dimensional (2D) transition metal dichalcogenides (TMDCs) and graphene compose a new family of crystalline materials with atomic thicknesses and exotic mechanical, electronic, and optical properties. Due to their inherent exceptional mechanical flexibility and strength, these 2D materials provide an ideal platform for strain engineering, enabling versatile modulation and significant enhancement of their optical properties. For instance, recent theoretical and experimental investigations have demonstrated flexible control over their electronic states via application of external strains, such as uniaxial strain and biaxial strain. Meanwhile, many nondestructive optical measurement methods, typically including absorption, reflectance, photoluminescence, and Raman spectroscopies, can be readily exploited to quantitatively determine strain-engineered optical properties. This review begins with an introduction to the macroscopic theory of crystal elasticity and microscopic effective low-energy Hamiltonians coupled with strain fields, and then summarizes recent advances in strain-induced optical responses of 2D TMDCs and graphene, followed by the strain engineering techniques. It concludes with exciting applications associated with strained 2D materials, discussions on existing open questions, and an outlook on this intriguing emerging field.
Collapse
Affiliation(s)
- Zhiwei Peng
- Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong, 999077, China
| | - Xiaolin Chen
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, 999077, China
| | - Yulong Fan
- Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong, 999077, China
| | - David J Srolovitz
- Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong, 999077, China
| | - Dangyuan Lei
- Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong, 999077, China.
| |
Collapse
|
26
|
Dielectric Elastomers UV-Cured from Poly(dimethylsiloxane) Solution in Vinyl Acetate. Polymers (Basel) 2020; 12:polym12112660. [PMID: 33187228 PMCID: PMC7697987 DOI: 10.3390/polym12112660] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 12/31/2022] Open
Abstract
Poly(dimethylsiloxane) (PDMS) has been extensively used as an electroactive polymer material because it exhibits not only excellent moldability but also mechanical properties sufficient enough for electroactive performance despite low dielectric permittivity. Its low dielectric property is due to its molecular non-polarity. Here, we introduce a polar group into a PDMS elastomer by using vinyl acetate (VAc) as a crosslinker to improve the dielectric permittivity. We synthesized a high-molecular weight PDMS copolymer containing vinyl groups, namely poly(dimethylsiloxane-co-methylvinylsiloxane) (VPDMS), and prepared several of the VPDMS solutions in VAc. We obtained transparent PDMS films by UV curing of the solution layers. Electromechanical actuation-related physical properties of one of the UV-cured films were almost equivalent to or superior to those of platinum-catalyzed hydrosilylation-cured PDMS films. In addition, saponification of the UV-cured film significantly improved the electrical and mechanical properties (ɛ′ ~ 44.1 pF/m at 10 kHz, E ~ 350 kPa, ɛ ~ 320%). The chemical introduction of VAc into PDMS main chains followed by saponification would offer an efficacious method of enhancing the electroactive properties of PDMS elastomers.
Collapse
|
27
|
Ahmad Tarar A, Mohammad U, K. Srivastava S. Wearable Skin Sensors and Their Challenges: A Review of Transdermal, Optical, and Mechanical Sensors. BIOSENSORS 2020; 10:E56. [PMID: 32481598 PMCID: PMC7345448 DOI: 10.3390/bios10060056] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 05/15/2020] [Accepted: 05/25/2020] [Indexed: 12/21/2022]
Abstract
Wearable technology and mobile healthcare systems are both increasingly popular solutions to traditional healthcare due to their ease of implementation and cost-effectiveness for remote health monitoring. Recent advances in research, especially the miniaturization of sensors, have significantly contributed to commercializing the wearable technology. Most of the traditional commercially available sensors are either mechanical or optical, but nowadays transdermal microneedles are also being used for micro-sensing such as continuous glucose monitoring. However, there remain certain challenges that need to be addressed before the possibility of large-scale deployment. The biggest challenge faced by all these wearable sensors is our skin, which has an inherent property to resist and protect the body from the outside world. On the other hand, biosensing is not possible without overcoming this resistance. Consequently, understanding the skin structure and its response to different types of sensing is necessary to remove the scientific barriers that are hindering our ability to design more efficient and robust skin sensors. In this article, we review research reports related to three different biosensing modalities that are commonly used along with the challenges faced in their implementation for detection. We believe this review will be of significant use to researchers looking to solve existing problems within the ongoing research in wearable sensors.
Collapse
Affiliation(s)
- Ammar Ahmad Tarar
- Department of Biological Engineering, University of Idaho, Moscow, ID 83844, USA;
| | - Umair Mohammad
- Department of Electrical & Computer Engineering, University of Idaho, Moscow, ID 83844, USA;
| | - Soumya K. Srivastava
- Department of Chemical & Materials Engineering, University of Idaho, Moscow, ID 83844, USA
| |
Collapse
|
28
|
Sousa RPCL, Ferreira B, Azenha M, Costa SPG, Silva CJR, Figueira RB. PDMS Based Hybrid Sol-Gel Materials for Sensing Applications in Alkaline Environments: Synthesis and Characterization. Polymers (Basel) 2020; 12:polym12020371. [PMID: 32046023 PMCID: PMC7077420 DOI: 10.3390/polym12020371] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 01/10/2020] [Accepted: 01/16/2020] [Indexed: 01/21/2023] Open
Abstract
Nowadays, concrete degradation is a major problem in the civil engineering field. Concrete carbonation, one of the main sources of structures' degradation, causes concrete's pH to decrease; hence, enabling the necessary conditions for corrosion reinforcement. An accurate, non-destructive sensor able to monitor the pH decrease resistant to concrete conditions is envisaged by many researchers. Optical fibre sensors (OFS) are generally used for concrete applications due to their high sensitivity and resistance to external interferences. Organic-inorganic hybrid (OIH) films, for potential functionalization of OFS to be applied in concrete structures, were developed. Polydimethylsiloxane (PDMS) based sol-gel materials were synthesized by the formation of an amino alcohol precursor followed by hydrolysis and condensation. Different ratios between PDMS and (3-aminopropyl)triethoxysilane (3-APTES) were studied. The synthesized OIH films were characterized by Fourier-transformed infrared spectroscopy (FTIR), UV-Vis spectroscopy, electrochemical impedance spectroscopy (EIS) and thermogravimetric analysis (TGA). The OIH films were doped with phenolphthalein (Phph), a pH indicator, and were characterized by UV-Vis and EIS. FTIR characterization showed that the reaction between both precursors, the hydrolysis and the condensation reactions occurred successfully. UV-Vis characterization confirmed the presence of Phph embedded in the OIH matrices. Dielectric and thermal properties of the materials showed promising properties for application in contact with a high alkaline environment.
Collapse
Affiliation(s)
- Rui P. C. L. Sousa
- Centro de Química, Campus de Gualtar, Universidade do Minho, 4710-057 Braga, Portugal; (B.F.); (S.P.G.C.); (C.J.R.S.)
- Correspondence: (R.P.C.L.S.); or (R.B.F.)
| | - Bárbara Ferreira
- Centro de Química, Campus de Gualtar, Universidade do Minho, 4710-057 Braga, Portugal; (B.F.); (S.P.G.C.); (C.J.R.S.)
| | - Miguel Azenha
- ISISE, Departamento de Engenharia Civil, Escola de Engenharia, Campus de Azurém, Universidade do Minho, 4800-058 Guimarães, Portugal;
| | - Susana P. G. Costa
- Centro de Química, Campus de Gualtar, Universidade do Minho, 4710-057 Braga, Portugal; (B.F.); (S.P.G.C.); (C.J.R.S.)
| | - Carlos J. R. Silva
- Centro de Química, Campus de Gualtar, Universidade do Minho, 4710-057 Braga, Portugal; (B.F.); (S.P.G.C.); (C.J.R.S.)
| | - Rita B. Figueira
- Centro de Química, Campus de Gualtar, Universidade do Minho, 4710-057 Braga, Portugal; (B.F.); (S.P.G.C.); (C.J.R.S.)
- Correspondence: (R.P.C.L.S.); or (R.B.F.)
| |
Collapse
|