1
|
Ali DS, Sofela SO, Deliorman M, Sukumar P, Abdulhamid MS, Yakubu S, Rooney C, Garrod R, Menachery A, Hijazi R, Saadi H, Qasaimeh MA. OMEF biochip for evaluating red blood cell deformability using dielectrophoresis as a diagnostic tool for type 2 diabetes mellitus. LAB ON A CHIP 2024; 24:2906-2919. [PMID: 38721867 DOI: 10.1039/d3lc01016c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Type 2 diabetes mellitus (T2DM) is a prevalent and debilitating disease with numerous health risks, including cardiovascular diseases, kidney dysfunction, and nerve damage. One important aspect of T2DM is its association with the abnormal morphology of red blood cells (RBCs), which leads to increased blood viscosity and impaired blood flow. Therefore, evaluating the mechanical properties of RBCs is crucial for understanding the role of T2DM in cellular deformability. This provides valuable insights into disease progression and potential diagnostic applications. In this study, we developed an open micro-electro-fluidic (OMEF) biochip technology based on dielectrophoresis (DEP) to assess the deformability of RBCs in T2DM. The biochip facilitates high-throughput single-cell RBC stretching experiments, enabling quantitative measurements of the cell size, strain, stretch factor, and post-stretching relaxation time. Our results confirm the significant impact of T2DM on the deformability of RBCs. Compared to their healthy counterparts, diabetic RBCs exhibit ∼27% increased size and ∼29% reduced stretch factor, suggesting potential biomarkers for monitoring T2DM. The observed dynamic behaviors emphasize the contrast between the mechanical characteristics, where healthy RBCs demonstrate notable elasticity and diabetic RBCs exhibit plastic behavior. These differences highlight the significance of mechanical characteristics in understanding the implications for RBCs in T2DM. With its ∼90% sensitivity and rapid readout (ultimately within a few minutes), the OMEF biochip holds potential as an effective point-of-care diagnostic tool for evaluating the deformability of RBCs in individuals with T2DM and tracking disease progression.
Collapse
Affiliation(s)
- Dima Samer Ali
- Division of Engineering, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.
- Department of Mechanical and Aerospace Engineering, New York University, New York, USA
| | - Samuel O Sofela
- Division of Engineering, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.
| | - Muhammedin Deliorman
- Division of Engineering, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.
| | - Pavithra Sukumar
- Division of Engineering, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.
| | - Ma-Sum Abdulhamid
- Division of Engineering, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.
| | - Sherifa Yakubu
- Division of Engineering, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.
| | - Ciara Rooney
- Cleveland Clinic Abu Dhabi (CCAD), Abu Dhabi, United Arab Emirates
| | - Ryan Garrod
- Cleveland Clinic Abu Dhabi (CCAD), Abu Dhabi, United Arab Emirates
| | - Anoop Menachery
- Division of Engineering, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.
- The Malta College of Arts, Science & Technology, Paola, Malta
| | - Rabih Hijazi
- Cleveland Clinic Abu Dhabi (CCAD), Abu Dhabi, United Arab Emirates
| | - Hussein Saadi
- Cleveland Clinic Abu Dhabi (CCAD), Abu Dhabi, United Arab Emirates
| | - Mohammad A Qasaimeh
- Division of Engineering, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.
- Department of Mechanical and Aerospace Engineering, New York University, New York, USA
- Department of Biomedical Engineering, New York University, New York, USA
| |
Collapse
|
2
|
Cheng Y, Pang SW. Biointerfaces with ultrathin patterns for directional control of cell migration. J Nanobiotechnology 2024; 22:158. [PMID: 38589901 PMCID: PMC11000378 DOI: 10.1186/s12951-024-02418-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Accepted: 03/18/2024] [Indexed: 04/10/2024] Open
Abstract
In the context of wound healing and tissue regeneration, precise control of cell migration direction is deemed crucial. To address this challenge, polydimethylsiloxane (PDMS) platforms with patterned 10 nm thick TiOx in arrowhead shape were designed and fabricated. Remarkably, without tall sidewall constraints, MC3T3-E1 cells seeded on these platforms were constrained to migrate along the tips of the arrowheads, as the cells were guided by the asymmetrical arrowhead tips which provided large contact areas. To the best of our knowledge, this is the first study demonstrating the use of thin TiOx arrowhead pattern in combination with a cell-repellent PDMS surface to provide guided cell migration unidirectionally without tall sidewall constraints. Additionally, high-resolution fluorescence imaging revealed that the asymmetrical distribution of focal adhesions, triggered by the patterned TiOx arrowheads with arm lengths of 10, 20, and 35 μm, promoted cell adhesion and protrusion along the arrowhead tip direction, resulting in unidirectional cell migration. These findings have important implications for the design of biointerfaces with ultrathin patterns to precisely control cell migration. Furthermore, microelectrodes were integrated with the patterned TiOx arrowheads to enable dynamic monitoring of cell migration using impedance measurement. This microfluidic device integrated with thin layer of guiding pattern and microelectrodes allows simultaneous control of directional cell migration and characterization of the cell movement of individual MC3T3-E1 cells, offering great potential for the development of biosensors for single-cell monitoring.
Collapse
Grants
- CityU11207620, CityU11207821, CityU11205423 Research Grants Council of the Hong Kong Special Administrative Region, China
- CityU11207620, CityU11207821, CityU11205423 Research Grants Council of the Hong Kong Special Administrative Region, China
- 9360148, 9380062 Center for Biosystems, Neuroscience, and Nanotechnology (CBNN) of City University of Hong Kong
- 9360148, 9380062 Center for Biosystems, Neuroscience, and Nanotechnology (CBNN) of City University of Hong Kong
Collapse
Affiliation(s)
- Yijun Cheng
- Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong, China
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Stella W Pang
- Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong, China.
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China.
| |
Collapse
|
3
|
Ayyanu R, Arul A, Song N, Anand Babu Christus A, Li X, Tamilselvan G, Bu Y, Kavitha S, Zhang Z, Liu N. Wearable sensor platforms for real-time monitoring and early warning of metabolic disorders in humans. Analyst 2023; 148:4616-4636. [PMID: 37712440 DOI: 10.1039/d3an01085f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
Nowadays, the prevalence of metabolic syndromes (MSs) has attracted increasing concerns as it is closely related to overweight and obesity, physical inactivity and overconsumption of energy, making the diagnosis and real-time monitoring of the physiological range essential and necessary for avoiding illness due to defects in the human body such as higher risk of cardiovascular disease, diabetes, stroke and diseases related to artery walls. However, the current sensing techniques are inconvenient and do not continuously monitor the health status of humans. Alternatively, the use of recent wearable device technology is a preferable method for the prevention of these diseases. This can enable the monitoring of the health status of humans in different health domains, including environment and structure. The use wearable devices with the purpose of facilitating rapid treatment and real-time monitoring can decrease the prevalence of MS and long-time monitor the health status of patients. This review highlights the recent advances in wearable sensors toward continuous monitoring of blood pressure and blood glucose, and further details the monitoring of abnormal obesity, triglycerides and HDL. We also discuss the challenges and future prospective of monitoring MS in humans.
Collapse
Affiliation(s)
- Ravikumar Ayyanu
- School of Emergency Management, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China.
| | - Amutha Arul
- Department of Chemistry, Francis Xavier Engineering College, Tirunelveli 627003, India
| | - Ninghui Song
- Nanjing Institute of Environmental Science, Key Laboratory of Pesticide Environmental Assessment and Pollution Control, Ministry of Ecology and Environment, Nanjing 210042, China.
| | - A Anand Babu Christus
- Department Chemistry, SRM Institute of Science and Technology, Ramapuram Campus, Ramapuram-600089, Chennai, Tamil Nadu, India
| | - Xuesong Li
- School of Emergency Management, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China.
| | - G Tamilselvan
- School of Emergency Management, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China.
| | - Yuanqing Bu
- Nanjing Institute of Environmental Science, Key Laboratory of Pesticide Environmental Assessment and Pollution Control, Ministry of Ecology and Environment, Nanjing 210042, China.
| | - S Kavitha
- Department of Chemistry, The M.D.T Hindu college (Affiliated to Manonmanium Sundaranar University), Tirunelveli-627010, Tamil Nadu, India
| | - Zhen Zhang
- School of Emergency Management, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China.
| | - Nan Liu
- Institute of Environment and Health, South China Hospital, Health Science Center, Shenzhen University, Shenzhen, 518116, P. R. China.
- Institute of Chronic Disease Risks Assessment, School of Nursing and Health, Henan University, Kaifeng, 475004, P. R. China
| |
Collapse
|
4
|
Shpun G, Farah N, Chemla Y, Markus A, Leibovitch TA, Lasnoy E, Gerber D, Zalevsky Z, Mandel Y. Optimizing the fabrication of a 3D high-resolution implant for neural stimulation. J Biol Eng 2023; 17:55. [PMID: 37620951 PMCID: PMC10463680 DOI: 10.1186/s13036-023-00370-8] [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: 09/12/2022] [Accepted: 07/24/2023] [Indexed: 08/26/2023] Open
Abstract
BACKGROUND Tissue-integrated micro-electronic devices for neural stimulation hold great potential in restoring the functionality of degenerated organs, specifically, retinal prostheses, which are aimed at vision restoration. The fabrication process of 3D polymer-metal devices with high resolution and a high aspect-ratio (AR) is very complex and faces many challenges that impair its functionality. APPROACH Here we describe the optimization of the fabrication process of a bio-functionalized 3D high-resolution 1mm circular subretinal implant composed of SU-8 polymer integrated with dense gold microelectrodes (23μm pitch) passivated with 3D micro-well-like structures (20μm diameter, 3μm resolution). The main challenges were overcome by step-by-step planning and optimization while utilizing a two-step bi-layer lift-off process; bio-functionalization was carried out by N2 plasma treatment and the addition of a bio-adhesion molecule. MAIN RESULTS In-vitro and in-vivo investigations, including SEM and FIB cross section examinations, revealed a good structural design, as well as a good long-term integration of the device in the rat sub-retinal space and cell migration into the wells. Moreover, the feasibility of subretinal neural stimulation using the fabricated device was demonstrated in-vitro by electrical activation of rat's retina. CONCLUSIONS The reported process and optimization steps described here in detail can aid in designing and fabricating retinal prosthetic devices or similar neural implants.
Collapse
Affiliation(s)
- Gal Shpun
- The Alexander Kofkin Faculty of Engineering, Bar Ilan University, 5290002, Ramat Gan, Israel
- Faculty of Life Sciences, School of Optometry & Visual Science, Bar Ilan University, 5290002, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology & Advanced Materials (BINA), Bar Ilan University, 5290002, Ramat Gan, Israel
| | - Nairouz Farah
- Faculty of Life Sciences, School of Optometry & Visual Science, Bar Ilan University, 5290002, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology & Advanced Materials (BINA), Bar Ilan University, 5290002, Ramat Gan, Israel
| | - Yoav Chemla
- Faculty of Life Sciences, School of Optometry & Visual Science, Bar Ilan University, 5290002, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology & Advanced Materials (BINA), Bar Ilan University, 5290002, Ramat Gan, Israel
| | - Amos Markus
- Faculty of Life Sciences, School of Optometry & Visual Science, Bar Ilan University, 5290002, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology & Advanced Materials (BINA), Bar Ilan University, 5290002, Ramat Gan, Israel
| | - Tamar Azrad Leibovitch
- Faculty of Life Sciences, School of Optometry & Visual Science, Bar Ilan University, 5290002, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology & Advanced Materials (BINA), Bar Ilan University, 5290002, Ramat Gan, Israel
| | - Erel Lasnoy
- Faculty of Life Sciences, School of Optometry & Visual Science, Bar Ilan University, 5290002, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology & Advanced Materials (BINA), Bar Ilan University, 5290002, Ramat Gan, Israel
| | - Doron Gerber
- Bar Ilan Institute for Nanotechnology & Advanced Materials (BINA), Bar Ilan University, 5290002, Ramat Gan, Israel
| | - Zeev Zalevsky
- The Alexander Kofkin Faculty of Engineering, Bar Ilan University, 5290002, Ramat Gan, Israel
- Bar Ilan Institute for Nanotechnology & Advanced Materials (BINA), Bar Ilan University, 5290002, Ramat Gan, Israel
| | - Yossi Mandel
- Faculty of Life Sciences, School of Optometry & Visual Science, Bar Ilan University, 5290002, Ramat Gan, Israel.
- Bar Ilan Institute for Nanotechnology & Advanced Materials (BINA), Bar Ilan University, 5290002, Ramat Gan, Israel.
- The Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel.
| |
Collapse
|
5
|
Roa CF, Singh N, Cherin E, Yin J, Boyes A, Foster FS, Demore CEM. Fine Pitch Flexible Printed Circuit Board Patterning for Miniaturized Endoscopic MicroUltrasound Arrays. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2022; 69:2785-2797. [PMID: 35797322 DOI: 10.1109/tuffc.2022.3189338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Microultrasound (micro-US) has become an invaluable tool for preclinical research and in emerging applications in clinical diagnosis and treatment guidance. Several such applications can benefit from arrays with a small footprint and endoscopic form factor. However, critical challenges arise in making electrical connections to array elements in such spatial constraints. In this work, we describe a method to pattern a high-density flexible circuit cabling on a copper-on polyimide film, using laser ablation of a polymer resist and wet etching, and then demonstrate a connection to a micro-US array. We investigate laser ablation process parameters and evaluate the ability to consistently pattern continuous copper traces. A minimum 30- [Formula: see text] pitch was achieved with 5- [Formula: see text]-wide electrode lines, and continuity of a 5-m-long trace is demonstrated. A flexible circuit with 30-mm-long traces with 30- [Formula: see text] line and 30- [Formula: see text] space before fan-out was fabricated to connect in an interleaved manner to a 32-element array with 30- [Formula: see text] element pitch. Metal deposition and laser ablation were used to connect and pattern the element electrodes to the copper traces of the flexible circuit. Electrical and acoustic measurements show good yield and consistent impedance across channels. Element pulse-echo tests demonstrated device functionality; the two-way pulse had 43-MHz center frequency and 40% fractional bandwidth (-6 dB). The proposed manufacturing methods facilitate the prototyping and fabrication of flexible endoscopic or small-footprint micro-US devices.
Collapse
|
6
|
Walton F, Cerezo-Sanchez M, McGlynn E, Das R, Heidari H. Cleanroom strategies for micro- and nano-fabricating flexible implantable neural electronics. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2022; 380:20210009. [PMID: 35658678 PMCID: PMC9168450 DOI: 10.1098/rsta.2021.0009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Implantable electronic neural interfaces typically take the form of probes and are made with rigid materials such as silicon and metals. These have advantages such as compatibility with integrated microchips, simple implantation and high-density nanofabrication but tend to be lacking in terms of biointegration, biocompatibility and durability due to their mechanical rigidity. This leads to damage to the device or, more importantly, the brain tissue surrounding the implant. Flexible polymer-based probes offer superior biocompatibility in terms of surface biochemistry and better matched mechanical properties. Research which aims to bring the fabrication of electronics on flexible polymer substrates to the nano-regime is remarkably sparse, despite the push for flexible consumer electronics in the last decade or so. Cleanroom-based nanofabrication techniques such as photolithography have been used as pattern transfer methods by the semiconductor industry to produce single nanometre scale devices and are now also used for making flexible circuit boards. There is still much scope for miniaturizing flexible electronics further using photolithography, bringing the possibility of nanoscale, non-invasive, high-density flexible neural interfacing. This work explores the fabrication challenges of using photolithography and complementary techniques in a cleanroom for producing flexible electronic neural probes with nanometre-scale features. This article is part of the theme issue 'Advanced neurotechnologies: translating innovation for health and well-being'.
Collapse
Affiliation(s)
- Finlay Walton
- Microelectronics Lab, James Watt School of Engineering, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Maria Cerezo-Sanchez
- Microelectronics Lab, James Watt School of Engineering, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Eve McGlynn
- Microelectronics Lab, James Watt School of Engineering, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Rupam Das
- Microelectronics Lab, James Watt School of Engineering, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Hadi Heidari
- Microelectronics Lab, James Watt School of Engineering, University of Glasgow, Glasgow, G12 8QQ, UK
| |
Collapse
|
7
|
Improvement in Strain Sensor Stability by Adapting the Metal Contact Layer. SENSORS 2022; 22:s22020630. [PMID: 35062593 PMCID: PMC8778142 DOI: 10.3390/s22020630] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 01/11/2022] [Accepted: 01/11/2022] [Indexed: 12/19/2022]
Abstract
Research on stretchable strain sensors is actively conducted due to increasing interest in wearable devices. However, typical studies have focused on improving the elasticity of the electrode. Therefore, methods of directly connecting wire or attaching conductive tape to materials to detect deformation have been used to evaluate the performance of strain sensors. Polyaniline (PANI), a p-type semiconductive polymer, has been widely used for stretchable electrodes. However, conventional procedures have limitations in determining an appropriate metal for ohmic contact with PANI. Materials that are generally used for connection with PANI form an undesirable metal-semiconductor junction and have significant contact resistance. Hence, they degrade sensor performance. This study secured ohmic contact by adapting Au thin film as the metal contact layer (the MCL), with lower contact resistance and a larger work function than PANI. Additionally, we presented a buffer layer using hard polydimethylsiloxane (PDMS) and structured it into a dumbbell shape to protect the metal from deformation. As a result, we enhanced steadiness and repeatability up to 50% strain by comparing the gauge factors and the relative resistance changes. Consequently, adapting structural methods (the MCL and the dumbbell shape) to a device can result in strain sensors with promising stability, as well as high stretchability.
Collapse
|
8
|
Near-field sub-diffraction photolithography with an elastomeric photomask. Nat Commun 2020; 11:805. [PMID: 32041949 PMCID: PMC7010681 DOI: 10.1038/s41467-020-14439-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 01/06/2020] [Indexed: 11/13/2022] Open
Abstract
Photolithography is the prevalent microfabrication technology. It needs to meet resolution and yield demands at a cost that makes it economically viable. However, conventional far-field photolithography has reached the diffraction limit, which imposes complex optics and short-wavelength beam source to achieve high resolution at the expense of cost efficiency. Here, we present a cost-effective near-field optical printing approach that uses metal patterns embedded in a flexible elastomer photomask with mechanical robustness. This technique generates sub-diffraction patterns that are smaller than 1/10th of the wavelength of the incoming light. It can be integrated into existing hardware and standard mercury lamp, and used for a variety of surfaces, such as curved, rough and defect surfaces. This method offers a higher resolution than common light-based printing systems, while enabling parallel-writing. We anticipate that it will be widely used in academic and industrial productions. Photolithography is an established microfabrication technique but commonly uses costly shortwavelength light sources to achieve high resolution. Here the authors use metal patterns embedded in a flexible elastomer photomask with mechanical robustness for generation of subdiffraction patterns as a cost effective near-field optical printing approach.
Collapse
|
9
|
Zia M, Chung B, Sober S, Bakir MS. Flexible Multielectrode Arrays With 2-D and 3-D Contacts for In Vivo Electromyography Recording. IEEE TRANSACTIONS ON COMPONENTS, PACKAGING, AND MANUFACTURING TECHNOLOGY 2020; 10:197-202. [PMID: 32280561 PMCID: PMC7150534 DOI: 10.1109/tcpmt.2019.2963556] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We present a system for recording in vivo electromyographic (EMG) signals from songbirds using hybrid polyimide-polydimethylsiloxane (PDMS) flexible multielectrode arrays (MEAs). 2-D electrodes with a diameter of 200, 125, and 50 μm and a center-to-center pitch of 300, 200, and 100 μm, respectively, were fabricated. 3-D MEAs were fabricated using a photoresist reflow process to obtain hemispherical domes utilized to form the 3-D electrodes. Biocompatibility and flexibility of the arrays were ensured by using polyimide and PDMS as the materials of choice for the arrays. EMG activity was recorded from the expiratory muscle group of anesthetized songbirds using the fabricated 2-D and 3-D arrays. Air pressure data were also recorded simultaneously from the air sac of the songbird. Together, EMG recordings and air pressure measurements can be used to characterize how the nervous system controls breathing and other motor behaviors. Such technologies can in turn provide unique insights into motor control in a range of species, including humans. An improvement of over 7× in the signal-to-noise ratio (SNR) is observed with the utilization of 3-D MEAs in comparison to 2-D MEAs.
Collapse
Affiliation(s)
- Muneeb Zia
- Department of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332 USA
| | - Bryce Chung
- Department of Biology, Emory University, Atlanta, GA 30322 USA
| | - Samuel Sober
- Department of Biology, Emory University, Atlanta, GA 30322 USA
| | - Muhannad S Bakir
- Department of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332 USA
| |
Collapse
|
10
|
Microfluidic devices with gold thin film channels for chemical and biomedical applications: a review. Biomed Microdevices 2019; 21:93. [DOI: 10.1007/s10544-019-0439-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
11
|
Femtosecond Laser-Based Modification of PDMS to Electrically Conductive Silicon Carbide. NANOMATERIALS 2018; 8:nano8070558. [PMID: 30037124 PMCID: PMC6071251 DOI: 10.3390/nano8070558] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 07/18/2018] [Accepted: 07/19/2018] [Indexed: 11/24/2022]
Abstract
In this paper, we experimentally demonstrate femtosecond laser direct writing of conductive structures on the surface of native polydimethylsiloxane (PDMS). Irradiation of femtosecond laser pulses modified the PDMS to black structures, which exhibit electrical conductivity. Fourier-transform infrared (FTIR) and X-ray diffraction (XRD) results show that the black structures were composed of β-silicon carbide (β-SiC), which can be attributed to the pyrolysis of the PDMS. The electrical conductivity was exhibited in limited laser power and scanning speed conditions. The technique we present enables the spatially selective formation of β-SiC on the surface of native PDMS only by irradiation of femtosecond laser pulses. Furthermore, this technique has the potential to open a novel route to simply fabricate flexible/stretchable MEMS devices with SiC microstructures.
Collapse
|
12
|
Tan EKW, Rughoobur G, Rubio-Lara J, Tiwale N, Xiao Z, Davidson CAB, Lowe CR, Occhipinti LG. Nanofabrication of Conductive Metallic Structures on Elastomeric Materials. Sci Rep 2018; 8:6607. [PMID: 29700337 PMCID: PMC5920093 DOI: 10.1038/s41598-018-24901-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 04/09/2018] [Indexed: 11/09/2022] Open
Abstract
Existing techniques for patterning metallic structures on elastomers are limited in terms of resolution, yield and scalability. The primary constraint is the incompatibility of their physical properties with conventional cleanroom techniques. We demonstrate a reliable fabrication strategy to transfer high resolution metallic structures of <500 nm in dimension on elastomers. The proposed method consists of producing a metallic pattern using conventional lithographic techniques on silicon coated with a thin sacrificial aluminium layer. Subsequent wet etching of the sacrificial layer releases the elastomer with the embedded metallic pattern. Using this method, a nano-resistor with minimum feature size of 400 nm is fabricated on polydimethylsiloxane (PDMS) and applied in gas sensing. Adsorption of solvents in the PDMS causes swelling and increases the device resistance, which therefore enables the detection of volatile organic compounds (VOCs). Sensitivity to chloroform and toluene vapor with a rapid response (~30 s) and recovery (~200 s) is demonstrated using this PDMS nano-resistor at room temperature.
Collapse
Affiliation(s)
- Edward K W Tan
- Department of Engineering, University of Cambridge, Cambridge, CB3 0FA, UK.
| | - Girish Rughoobur
- Department of Engineering, University of Cambridge, Cambridge, CB3 0FA, UK.,Microsystems Technology Laboratories, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Juan Rubio-Lara
- Nanoscience Centre, University of Cambridge, Cambridge, CB3 0FF, UK
| | - Nikhil Tiwale
- Nanoscience Centre, University of Cambridge, Cambridge, CB3 0FF, UK
| | - Zhuocong Xiao
- Nanoscience Centre, University of Cambridge, Cambridge, CB3 0FF, UK
| | - Colin A B Davidson
- Institute of Biotechnology, University of Cambridge, Cambridge, CB2 1QT, UK
| | - Christopher R Lowe
- Institute of Biotechnology, University of Cambridge, Cambridge, CB2 1QT, UK
| | - Luigi G Occhipinti
- Department of Engineering, University of Cambridge, Cambridge, CB3 0FA, UK.
| |
Collapse
|
13
|
Mirvakili SM, Hunter IW. Artificial Muscles: Mechanisms, Applications, and Challenges. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:1704407. [PMID: 29250838 DOI: 10.1002/adma.201704407] [Citation(s) in RCA: 323] [Impact Index Per Article: 53.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 09/10/2017] [Indexed: 05/22/2023]
Abstract
The area of artificial muscle is a highly interdisciplinary field of research that has evolved rapidly in the last 30 years. Recent advances in nanomaterial fabrication and characterization, specifically carbon nanotubes and nanowires, have had major contributions in the development of artificial muscles. However, what can artificial muscles really do for humans? This question is considered here by first examining nature's solutions to this design problem and then discussing the structure, actuation mechanism, applications, and limitations of recently developed artificial muscles, including highly oriented semicrystalline polymer fibers; nanocomposite actuators; twisted nanofiber yarns; thermally activated shape-memory alloys; ionic-polymer/metal composites; dielectric-elastomer actuators; conducting polymers; stimuli-responsive gels; piezoelectric, electrostrictive, magnetostrictive, and photostrictive actuators; photoexcited actuators; electrostatic actuators; and pneumatic actuators.
Collapse
Affiliation(s)
- Seyed M Mirvakili
- BioInstrumentation Laboratory, Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Ian W Hunter
- BioInstrumentation Laboratory, Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| |
Collapse
|
14
|
Guvanasen GS, Guo L, Aguilar RJ, Cheek AL, Shafor CS, Rajaraman S, Nichols TR, DeWeerth SP. A Stretchable Microneedle Electrode Array for Stimulating and Measuring Intramuscular Electromyographic Activity. IEEE Trans Neural Syst Rehabil Eng 2017; 25:1440-1452. [DOI: 10.1109/tnsre.2016.2629461] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
15
|
Hybrid Microfluidic Platform for Multifactorial Analysis Based on Electrical Impedance, Refractometry, Optical Absorption and Fluorescence. MICROMACHINES 2016; 7:mi7100181. [PMID: 30404355 PMCID: PMC6190102 DOI: 10.3390/mi7100181] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 09/12/2016] [Accepted: 09/26/2016] [Indexed: 11/18/2022]
Abstract
This paper describes the development of a novel microfluidic platform for multifactorial analysis integrating four label-free detection methods: electrical impedance, refractometry, optical absorption and fluorescence. We present the rationale for the design and the details of the microfabrication of this multifactorial hybrid microfluidic chip. The structure of the platform consists of a three-dimensionally patterned polydimethylsiloxane top part attached to a bottom SU-8 epoxy-based negative photoresist part, where microelectrodes and optical fibers are incorporated to enable impedance and optical analysis. As a proof of concept, the chip functions have been tested and explored, enabling a diversity of applications: (i) impedance-based identification of the size of micro beads, as well as counting and distinguishing of erythrocytes by their volume or membrane properties; (ii) simultaneous determination of the refractive index and optical absorption properties of solutions; and (iii) fluorescence-based bead counting.
Collapse
|
16
|
Zhou C, Bette S, Schnakenberg U. Flexible and Stretchable Gold Microstructures on Extra Soft Poly(dimethylsiloxane) Substrates. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2015; 27:6664-9. [PMID: 26414621 DOI: 10.1002/adma.201502630] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 07/23/2015] [Indexed: 05/27/2023]
Abstract
Stretchable gold microstructures are reliably transferred onto an extra-soft elastomeric substrate. Several major challenges, including failure-free transfer and reliable bonding with the substrate, are addressed. The simple and reproducible fabrication allows extensive study and optimization of the stretchability of meanders in terms of thickness, geometry, and substrate. The results provide new insights for designing stretchable electronics and novel routes for stretchrelated, mechanobiological cell-interface applications.
Collapse
Affiliation(s)
- Chen Zhou
- Institute of Materials in Electrical Engineering 1, RWTH Aachen University, Sommerfeldstraße 24, 52074, Aachen, Germany
| | - Sebastian Bette
- Institute of Materials in Electrical Engineering 1, RWTH Aachen University, Sommerfeldstraße 24, 52074, Aachen, Germany
| | - Uwe Schnakenberg
- Institute of Materials in Electrical Engineering 1, RWTH Aachen University, Sommerfeldstraße 24, 52074, Aachen, Germany
| |
Collapse
|
17
|
Effects of Fumed and Mesoporous Silica Nanoparticles on the Properties of Sylgard 184 Polydimethylsiloxane. MICROMACHINES 2015. [DOI: 10.3390/mi6070855] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
18
|
Martinez V, Stauffer F, Adagunodo MO, Forro C, Vörös J, Larmagnac A. Stretchable Silver Nanowire-Elastomer Composite Microelectrodes with Tailored Electrical Properties. ACS APPLIED MATERIALS & INTERFACES 2015; 7:13467-75. [PMID: 26068389 DOI: 10.1021/acsami.5b02508] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We introduce a photolithography process compatible with soft and rigid substrates, enabling the fabrication of complex 3D interconnected patterns of silver nanowire (AgNW) networks embedded in polydimethylsiloxane (PDMS). Dimensions of the AgNW micropatterns are controlled within the film plane by photolithography, whereas thickness is controlled via a novel and uniform deposition technique using centrifugation. We report the first systematic characterization of the electromechanical properties of such microelectrodes with finest stretchable feature of 15 μm. We observe a geometry-dependent behavior of the gauge factor not only by changing the thickness of the microelectrodes, as it has been commonly reported so far, but also by varying their lateral dimensions. The presented nanocomposites exhibited sheet resistances down to 0.6 Ω/sq, gauge factors ranging from 0.01 to 100, and stretchability above 50% uniaxial strain. This versatile process allows for the production of highly sensitive strain sensors and robust high-density stretchable conductors on a wafer scale with direct implications in mass production of stretchable electronic devices.
Collapse
Affiliation(s)
- Vincent Martinez
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, ETH Zurich, Gloriastrasse 35, ETZ F76, CH-8092 Zurich, Switzerland
| | - Flurin Stauffer
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, ETH Zurich, Gloriastrasse 35, ETZ F76, CH-8092 Zurich, Switzerland
| | - Mohammed O Adagunodo
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, ETH Zurich, Gloriastrasse 35, ETZ F76, CH-8092 Zurich, Switzerland
| | - Csaba Forro
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, ETH Zurich, Gloriastrasse 35, ETZ F76, CH-8092 Zurich, Switzerland
| | - Janos Vörös
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, ETH Zurich, Gloriastrasse 35, ETZ F76, CH-8092 Zurich, Switzerland
| | - Alexandre Larmagnac
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, ETH Zurich, Gloriastrasse 35, ETZ F76, CH-8092 Zurich, Switzerland
| |
Collapse
|
19
|
Wu J, Wang R, Yu H, Li G, Xu K, Tien NC, Roberts RC, Li D. Inkjet-printed microelectrodes on PDMS as biosensors for functionalized microfluidic systems. LAB ON A CHIP 2015; 15:690-5. [PMID: 25412449 DOI: 10.1039/c4lc01121j] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Microfluidic systems based on polydimethylsiloxane (PDMS) have gained popularity in recent years. However, microelectrode patterning on PDMS to form biosensors in microchannels remains a worldwide technical issue due to the hydrophobicity of PDMS and its weak adhesion to metals. In this study, an additive technique using inkjet-printed silver nanoparticles to form microelectrodes on PDMS is presented. (3-Mercaptopropyl)trimethoxysilane (MPTMS) was used to modify the surface of PDMS to improve its surface wettability and its adhesion to silver. The modified surface of PDMS is rendered relatively hydrophilic, which is beneficial for the silver droplets to disperse and thus effectively avoids the coalescence of adjacent droplets. Additionally, a multilevel matrix deposition (MMD) method is used to further avoid the coalescence and yield a homogeneous pattern on the MPTMS-modified PDMS. A surface wettability comparison and an adhesion test were conducted. The resulting silver pattern exhibited good uniformity, conductivity and excellent adhesion to PDMS. A three-electrode electrochemical biosensor was fabricated successfully using this method and sealed in a PDMS microchannel, forming a lab-on-a-chip glucose biosensing system.
Collapse
Affiliation(s)
- Jianwei Wu
- State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin, China.
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Tseng P, Pushkarsky I, Di Carlo D. Metallization and biopatterning on ultra-flexible substrates via dextran sacrificial layers. PLoS One 2014; 9:e106091. [PMID: 25153326 PMCID: PMC4143360 DOI: 10.1371/journal.pone.0106091] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 07/31/2014] [Indexed: 11/23/2022] Open
Abstract
Micro-patterning tools adopted from the semiconductor industry have mostly been optimized to pattern features onto rigid silicon and glass substrates, however, recently the need to pattern on soft substrates has been identified in simulating cellular environments or developing flexible biosensors. We present a simple method of introducing a variety of patterned materials and structures into ultra-flexible polydimethylsiloxane (PDMS) layers (elastic moduli down to 3 kPa) utilizing water-soluble dextran sacrificial thin films. Dextran films provided a stable template for photolithography, metal deposition, particle adsorption, and protein stamping. These materials and structures (including dextran itself) were then readily transferrable to an elastomer surface following PDMS (10 to 70∶1 base to crosslinker ratios) curing over the patterned dextran layer and after sacrificial etch of the dextran in water. We demonstrate that this simple and straightforward approach can controllably manipulate surface wetting and protein adsorption characteristics of PDMS, covalently link protein patterns for stable cell patterning, generate composite structures of epoxy or particles for study of cell mechanical response, and stably integrate certain metals with use of vinyl molecular adhesives. This method is compatible over the complete moduli range of PDMS, and potentially generalizable over a host of additional micro- and nano-structures and materials.
Collapse
Affiliation(s)
- Peter Tseng
- Department of Bioengineering, University of California Los Angeles, Los Angeles, California, United States of America
| | - Ivan Pushkarsky
- Department of Bioengineering, University of California Los Angeles, Los Angeles, California, United States of America
| | - Dino Di Carlo
- Department of Bioengineering, University of California Los Angeles, Los Angeles, California, United States of America
- * E-mail:
| |
Collapse
|
21
|
Hammock ML, Chortos A, Tee BCK, Tok JBH, Bao Z. 25th anniversary article: The evolution of electronic skin (e-skin): a brief history, design considerations, and recent progress. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2013; 25:5997-6038. [PMID: 24151185 DOI: 10.1002/adma.201302240] [Citation(s) in RCA: 882] [Impact Index Per Article: 80.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 06/22/2013] [Indexed: 05/19/2023]
Abstract
Human skin is a remarkable organ. It consists of an integrated, stretchable network of sensors that relay information about tactile and thermal stimuli to the brain, allowing us to maneuver within our environment safely and effectively. Interest in large-area networks of electronic devices inspired by human skin is motivated by the promise of creating autonomous intelligent robots and biomimetic prosthetics, among other applications. The development of electronic networks comprised of flexible, stretchable, and robust devices that are compatible with large-area implementation and integrated with multiple functionalities is a testament to the progress in developing an electronic skin (e-skin) akin to human skin. E-skins are already capable of providing augmented performance over their organic counterpart, both in superior spatial resolution and thermal sensitivity. They could be further improved through the incorporation of additional functionalities (e.g., chemical and biological sensing) and desired properties (e.g., biodegradability and self-powering). Continued rapid progress in this area is promising for the development of a fully integrated e-skin in the near future.
Collapse
Affiliation(s)
- Mallory L Hammock
- Department of Chemical Engineering, 381 N. South Axis, Stanford University, Stanford, CA, 94305, USA
| | | | | | | | | |
Collapse
|
22
|
Guvanasen GS, Tuthill C, Nichols TR, DeWeerth SP. A PDMS-based integrated stretchable microelectrode array (isMEA) for neural and muscular surface interfacing. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2013; 7:1-10. [PMID: 23853274 DOI: 10.1109/tbcas.2012.2192932] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Numerous applications in neuroscience research and neural prosthetics, such as electrocorticogram (ECoG) recording and retinal prosthesis, involve electrical interactions with soft excitable tissues using a surface recording and/or stimulation approach. These applications require an interface that is capable of setting up high-throughput communications between the electrical circuit and the excitable tissue and that can dynamically conform to the shape of the soft tissue. Being a compliant material with mechanical impedance close to that of soft tissues, polydimethylsiloxane (PDMS) offers excellent potential as a substrate material for such neural interfaces. This paper describes an integrated technology for fabrication of PDMS-based stretchable microelectrode arrays (MEAs). Specifically, as an integral part of the fabrication process, a stretchable MEA is directly fabricated with a rigid substrate, such as a thin printed circuit board (PCB), through an innovative bonding technology-via-bonding-for integrated packaging. This integrated strategy overcomes the conventional challenge of high-density packaging for this type of stretchable electronics. Combined with a high-density interconnect technology developed previously, this stretchable MEA technology facilitates a high-resolution, high-density integrated system solution for neural and muscular surface interfacing. In this paper, this PDMS-based integrated stretchable MEA (isMEA) technology is demonstrated by an example design that packages a stretchable MEA with a small PCB. The resulting isMEA is assessed for its biocompatibility, surface conformability, electrode impedance spectrum, and capability to record muscle fiber activity when applied epimysially.
Collapse
|
23
|
Du K, Wathuthanthri I, Liu Y, Xu W, Choi CH. Wafer-scale pattern transfer of metal nanostructures on polydimethylsiloxane (PDMS) substrates via holographic nanopatterns. ACS APPLIED MATERIALS & INTERFACES 2012; 4:5505-14. [PMID: 23020206 DOI: 10.1021/am301423s] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
In this paper, we report on a cost-effective and simple, nondestructive pattern transfer method that allows the fabrication of metallic nanostructures on a polydimethylsiloxane (PDMS) substrate on a wafer scale. The key idea is to use holographic nanopatterns of a photoresist (PR) layer as template structures, where a metal film is directly deposited in order to replicate the nanopatterns of the PR template layer. Then, the PDMS elastomer is molded onto the metal film and the metal/PDMS composite layer is directly peeled off from the PR surface. Many metallic materials including Ti, Al, and Ag were successfully nanopatterned on PDMS substrates by the pattern transfer process with no use of any adhesion promoter layer or coating. In case of Au that has poor adhesion to PDMS material, a salinization of the metal surface with 3-(aminopropyl)-triethoxysilane (APTES) monolayer promoted the adhesion and led to successful pattern transfer. A series of adhesion tests confirmed the good adhesion of the transferred metal films onto the molded PDMS substrates, including scotch-tape and wet immersion tests. The inexpensive and robust pattern transfer approach of metallic nanostructures onto transparent and flexible PDMS substrates will open the new door for many scientific and engineering applications such as micro-/nanofluidics, optofluidics, nanophotonics, and nanoelectronics.
Collapse
Affiliation(s)
- Ke Du
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, New Jersey 07030, USA
| | | | | | | | | |
Collapse
|