1
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Xu W, Atik AY, Beker L, Ceylan Koydemir H. Digital monitoring of the microchannel filling flow dynamics using a non-contactless smartphone-based nano-liter precision flow velocity meter. Biosens Bioelectron 2024; 252:116130. [PMID: 38417285 DOI: 10.1016/j.bios.2024.116130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 01/21/2024] [Accepted: 02/11/2024] [Indexed: 03/01/2024]
Abstract
Microfluidic systems find widespread applications in diagnostics, biological research, chemistry, and engineering studies. Among their many critical parameters, flow rate plays a pivotal role in maintaining the functionality of microfluidic systems, including droplet-based microfluidic devices and those used in cell culture. It also significantly influences microfluidic mixing processes. Although various flow rate measurement devices have been developed, the challenge remains in accurately measuring flow rates within customized channels. This paper presents the development of a 3D-printed smartphone-based flow velocity meter. The 3D-printed platform is angled at 30° to achieve transparent flow visualization, and it doesn't require any external optical components such as external lenses and filters. Two LED modules integrated into the platform create a uniform illumination environment for video capture, powered directly by the smartphone. The performance of our platform, combined with a customized video processing algorithm, was assessed in three different channel types: uniform straight channels, straight channels with varying widths, and vessel-like channel patterns to demonstrate its versatility. Our device effectively measured flow velocities from 5.43 mm/s to 24.47 mm/s, with video quality at 1080p resolution and 60 frames per second, for which the measurement range can be extended by adjusting the frame rate. This flow velocity meter can be a useful analytical tool to evaluate and enhance microfluidic channel designs of various lab-on-a-chip applications.
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Affiliation(s)
- Weiming Xu
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA; Center for Remote Health Technologies and Systems, Texas A&M Engineering Experiment Station, College Station, TX, 77843, USA
| | - Abdulkadir Yasin Atik
- Department of Mechanical Engineering, Koç University, Sariyer, Istanbul, 34450, Turkey
| | - Levent Beker
- Department of Mechanical Engineering, Koç University, Sariyer, Istanbul, 34450, Turkey
| | - Hatice Ceylan Koydemir
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA; Center for Remote Health Technologies and Systems, Texas A&M Engineering Experiment Station, College Station, TX, 77843, USA.
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2
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Istif E, Ali M, Ozuaciksoz EY, Morova Y, Beker L. Near-Infrared Triggered Degradation for Transient Electronics. ACS Omega 2024; 9:2528-2535. [PMID: 38250408 PMCID: PMC10795112 DOI: 10.1021/acsomega.3c07203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 11/07/2023] [Accepted: 12/21/2023] [Indexed: 01/23/2024]
Abstract
Electronics that disintegrate after stable operation present exciting opportunities for niche medical implant and consumer electronics applications. The disintegration of these devices can be initiated due to their medium conditions or triggered by external stimuli, which enables on-demand transition. An external stimulation method that can penetrate deep inside the body could revolutionize the use of transient electronics as implantable medical devices (IMDs), eliminating the need for secondary surgery to remove the IMDs. We report near-infrared (NIR) light-triggered transition of metastable cyclic poly(phthalaldehyde) (cPPA) polymers. The transition of the encapsulation layer is achieved through the conversion of NIR light to heat, facilitated by bioresorbable metals, such as molybdenum (Mo). We reported a rapid degradation of cPPA encapsulation layer about 1 min, and the rate of degradation can be controlled by laser power and exposure time. This study offers a new approach for light triggerable transient electronics for IMDs due to the deep penetration depth of NIR light through to organs and tissues.
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Affiliation(s)
- Emin Istif
- Department
of Molecular Biology and Genetics, Faculty of Engineering and Natural
Science, Kadir Has University, Istanbul 34083, Turkey
| | - Mohsin Ali
- Department
of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul 34450, Turkey
| | - Elif Yaren Ozuaciksoz
- Department
of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul 34450, Turkey
| | - Yagız Morova
- Koç
University Surface Science and Technology Center (KUYTAM), Rumelifeneri, Istanbul 34450, Turkey
| | - Levent Beker
- Department
of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul 34450, Turkey
- Nanofabrication
and Nanocharacterization Centre for Scientific and Technological Advanced
Research, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul 34450, Turkey
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3
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Abbasiasl T, Mirlou F, Mirzajani H, Bathaei MJ, Istif E, Shomalizadeh N, Cebecioğlu RE, Özkahraman EE, Yener UC, Beker L. A Wearable Touch-Activated Device Integrated with Hollow Microneedles for Continuous Sampling and Sensing of Dermal Interstitial Fluid. Adv Mater 2024; 36:e2304704. [PMID: 37709513 DOI: 10.1002/adma.202304704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 08/20/2023] [Indexed: 09/16/2023]
Abstract
Dermal interstitial fluid (ISF) is emerging as a rich source of biomarkers that complements conventional biofluids such as blood and urine. However, the impact of ISF sampling in clinical applications has been limited owing to the challenges associated with extraction. The implementation of microneedle-based wearable devices that can extract dermal ISF in a pain-free and easy-to-use manner has attracted growing attention in recent years. Here, a fully integrated touch-activated wearable device based on a laser-drilled hollow microneedle (HMN) patch for continuous sampling and sensing of dermal ISF is introduced. The developed platform can produce and maintain the required vacuum pressure (as low as ≈ -53 kPa) to collect adequate volumes of ISF (≈2 µL needle-1 h-1 ) for medical applications. The vacuum system can be activated through a one-touch finger operation. A parametric study is performed to investigate the effect of microneedle array size, vacuum pressure, and extraction duration on collected ISF. The capability of the proposed platform for continuous health monitoring is further demonstrated by the electrochemical detection of glucose and pH levels of ISF in animal models. This HMN-based system provides an alternative tool to the existing invasive techniques for ISF collection and sensing for medical diagnosis and treatment.
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Affiliation(s)
- Taher Abbasiasl
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Fariborz Mirlou
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Hadi Mirzajani
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Mohammad Javad Bathaei
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Emin Istif
- Faculty of Engineering and Natural Sciences, Kadir Has University, Cibali, Istanbul, 34083, Turkey
| | - Narges Shomalizadeh
- Koç University Research Center for Translational Research (KUTTAM), Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Rümeysa Emine Cebecioğlu
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Ecem Ezgi Özkahraman
- Department of Material Science and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Umut Can Yener
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Levent Beker
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
- Koç University Research Center for Translational Research (KUTTAM), Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
- Nanofabrication and Nanocharacterization Center for Scientific and Technological Advanced Research (n2Star), Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
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4
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Ali M, Bathaei MJ, Istif E, Karimi SNH, Beker L. Biodegradable Piezoelectric Polymers: Recent Advancements in Materials and Applications. Adv Healthc Mater 2023; 12:e2300318. [PMID: 37235849 DOI: 10.1002/adhm.202300318] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 05/21/2023] [Indexed: 05/28/2023]
Abstract
Recent materials, microfabrication, and biotechnology improvements have introduced numerous exciting bioelectronic devices based on piezoelectric materials. There is an intriguing evolution from conventional unrecyclable materials to biodegradable, green, and biocompatible functional materials. As a fundamental electromechanical coupling material in numerous applications, novel piezoelectric materials with a feature of degradability and desired electrical and mechanical properties are being developed for future wearable and implantable bioelectronics. These bioelectronics can be easily integrated with biological systems for applications, including sensing physiological signals, diagnosing medical problems, opening the blood-brain barrier, and stimulating healing or tissue growth. Therefore, the generation of piezoelectricity from natural and synthetic bioresorbable polymers has drawn great attention in the research field. Herein, the significant and recent advancements in biodegradable piezoelectric materials, including natural and synthetic polymers, their principles, advanced applications, and challenges for medical uses, are reviewed thoroughly. The degradation methods of these piezoelectric materials through in vitro and in vivo studies are also investigated. These improvements in biodegradable piezoelectric materials and microsystems could enable new applications in the biomedical field. In the end, potential research opportunities regarding the practical applications are pointed out that might be significant for new materials research.
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Affiliation(s)
- Mohsin Ali
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Mohammad Javad Bathaei
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Emin Istif
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
- Faculty of Engineering and Natural Sciences, Kadir Has University, Cibali, Istanbul, 34083, Turkey
| | - Seyed Nasir Hosseini Karimi
- Koç University Research Center for Translational Research (KUTTAM), Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Levent Beker
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
- Koç University Research Center for Translational Research (KUTTAM), Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
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5
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Istif E, Mirzajani H, Dağ Ç, Mirlou F, Ozuaciksoz EY, Cakır C, Koydemir HC, Yilgor I, Yilgor E, Beker L. Miniaturized wireless sensor enables real-time monitoring of food spoilage. Nat Food 2023; 4:427-436. [PMID: 37202486 DOI: 10.1038/s43016-023-00750-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 04/11/2023] [Indexed: 05/20/2023]
Abstract
Food spoilage results in food waste and food-borne diseases. Yet, standard laboratory tests to determine spoilage (mainly volatile biogenic amines) are not performed regularly by supply chain personnel or end customers. Here we developed a poly(styrene-co-maleic anhydride)-based, miniature (2 × 2 cm2) sensor for on-demand spoilage analysis via mobile phones. To demonstrate a real-life application, the wireless sensor was embedded into packaged chicken and beef; consecutive readings from meat samples using the sensor under various storage conditions enabled the monitoring of spoilage. While samples stored at room temperature showed an almost 700% change in sensor response on the third day, those stored in the freezer resulted in an insignificant change in sensor output. The proposed low-cost, miniature wireless sensor nodes can be integrated into packaged foods, helping consumers and suppliers detect spoilage of protein-rich foods on demand, and ultimately preventing food waste and food-borne diseases.
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Affiliation(s)
- Emin Istif
- Department of Mechanical Engineering, Koç University, Istanbul, Turkey.
- Department of Molecular Biology and Genetics, Faculty of Engineering and Natural Science, Kadir Has University, Istanbul, Turkey.
| | - Hadi Mirzajani
- Department of Mechanical Engineering, Koç University, Istanbul, Turkey
| | - Çağdaş Dağ
- Nanofabrication and Nanocharacterization Centre for Scientific and Technological Advanced Research, Koç University, Istanbul, Turkey
- Koç University İşBank Centre for Infectious Diseases, Koç University, Istanbul, Turkey
| | - Fariborz Mirlou
- Department of Biomedical Sciences and Engineering, Koç University, Istanbul, Turkey
| | | | - Cengiz Cakır
- Department of Electronics and Communication Engineering, Istanbul Technical University, Istanbul, Turkey
| | - Hatice Ceylan Koydemir
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA
- Center for Remote Health Technologies and Systems, Texas A&M University, College Station, TX, USA
| | | | - Emel Yilgor
- Department of Chemistry, Koç University, Istanbul, Turkey
| | - Levent Beker
- Department of Mechanical Engineering, Koç University, Istanbul, Turkey.
- Nanofabrication and Nanocharacterization Centre for Scientific and Technological Advanced Research, Koç University, Istanbul, Turkey.
- Department of Biomedical Sciences and Engineering, Koç University, Istanbul, Turkey.
- Koç University Research Center for Translational Research, Koç University, Istanbul, Turkey.
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6
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Bathaei MJ, Singh R, Mirzajani H, Istif E, Akhtar MJ, Abbasiasl T, Beker L. Photolithography-Based Microfabrication of Biodegradable Flexible and Stretchable Sensors. Adv Mater 2023; 35:e2207081. [PMID: 36401580 DOI: 10.1002/adma.202207081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 11/12/2022] [Indexed: 06/16/2023]
Abstract
Biodegradable sensors based on integrating conductive layers with polymeric materials in flexible and stretchable forms have been established. However, the lack of a generalized microfabrication method results in large-sized, low spatial density, and low device yield compared to the silicon-based devices manufactured via batch-compatible microfabrication processes. Here, a batch fabrication-compatible photolithography-based microfabrication approach for biodegradable and highly miniaturized essential sensor components is presented on flexible and stretchable substrates. Up to 1600 devices are fabricated within a 1 cm2 footprint and then the functionality of various biodegradable passive electrical components, mechanical sensors, and chemical sensors is demonstrated on flexible and stretchable substrates. The results are highly repeatable and consistent, proving the proposed method's high device yield and high-density potential. This simple, innovative, and robust fabrication recipe allows complete freedom over the applicability of various biodegradable materials with different properties toward the unique application of interests. The process offers a route to utilize standard micro-fabrication procedures toward scalable fabrication of highly miniaturized flexible and stretchable transient sensors and electronics.
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Affiliation(s)
- Mohammad Javad Bathaei
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Rahul Singh
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Hadi Mirzajani
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Emin Istif
- Faculty of Engineering and Natural Sciences, Kadir Has University, Cibali, Istanbul, 34083, Turkey
| | - Muhammad Junaid Akhtar
- Department of Electrical and Electronics Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Taher Abbasiasl
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Levent Beker
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
- Research Center for Translational Medicine (KUTTAM), Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
- Nanofabrication and Nanocharacterization Center for Scientific and Technological Advanced Research (n2Star), Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
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7
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Li TL, Liu Y, Forro C, Yang X, Beker L, Bao Z, Cui B, Pașca SP. Stretchable mesh microelectronics for the biointegration and stimulation of human neural organoids. Biomaterials 2022; 290:121825. [PMID: 36326509 PMCID: PMC9879137 DOI: 10.1016/j.biomaterials.2022.121825] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 09/16/2022] [Accepted: 09/24/2022] [Indexed: 02/03/2023]
Abstract
Advances in tridimensional (3D) culture approaches have led to the generation of organoids that recapitulate cellular and physiological features of domains of the human nervous system. Although microelectrodes have been developed for long-term electrophysiological interfaces with neural tissue, studies of long-term interfaces between microelectrodes and free-floating organoids remain limited. In this study, we report a stretchable, soft mesh electrode system that establishes an intimate in vitro electrical interface with human neurons in 3D organoids. Our mesh is constructed with poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) based electrically conductive hydrogel electrode arrays and elastomeric poly(styrene-ethylene-butylene-styrene) (SEBS) as the substrate and encapsulation materials. This mesh electrode can maintain a stable electrochemical impedance in buffer solution under 50% compressive and 50% tensile strain. We have successfully cultured pluripotent stem cell-derived human cortical organoids (hCO) on this polymeric mesh for more than 3 months and demonstrated that organoids readily integrate with the mesh. Using simultaneous stimulation and calcium imaging, we show that electrical stimulation through the mesh can elicit intensity-dependent calcium signals comparable to stimulation from a bipolar stereotrode. This platform may serve as a tool for monitoring and modulating the electrical activity of in vitro models of neuropsychiatric diseases.
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Affiliation(s)
- Thomas L Li
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA; Department of Chemistry, Stanford University, Stanford, CA, 94305, USA
| | - Yuxin Liu
- Department of Chemical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Csaba Forro
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Xiao Yang
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA; Department of Chemistry, Stanford University, Stanford, CA, 94305, USA
| | - Levent Beker
- Department of Chemical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Zhenan Bao
- Department of Chemical Engineering, Stanford University, Stanford, CA, 94305, USA.
| | - Bianxiao Cui
- Department of Chemistry, Stanford University, Stanford, CA, 94305, USA.
| | - Sergiu P Pașca
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305, USA; Stanford Brain Organogenesis, Wu Tsai Neuroscience Institute, Stanford, CA, 94305, USA.
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8
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Mirzajani H, Abbasiasl T, Mirlou F, Istif E, Bathaei MJ, Dağ Ç, Deyneli O, Yazıcı D, Beker L. An ultra-compact and wireless tag for battery-free sweat glucose monitoring. Biosens Bioelectron 2022; 213:114450. [PMID: 35688025 DOI: 10.1016/j.bios.2022.114450] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/29/2022] [Accepted: 05/31/2022] [Indexed: 11/02/2022]
Abstract
Glucose monitoring before, during, and after exercise is essential for people with diabetes as exercise increases the risk of activity-induced hyper- and hypo-glycemic events. The situation is even more challenging for athletes with diabetes as they have impaired metabolic control compared to sedentary individuals. In this regard, a compact and noninvasive wearable glucose monitoring device that can be easily worn is critical to enabling glucose monitoring. This report presents an ultra-compact glucose tag with a footprint and weight of 1.2 cm2 and 0.13 g, respectively, for sweat analysis. The device comprises a near field communication (NFC) chip, antenna, electrochemical sensor, and microfluidic channels implemented in different material layers. The device has a flexible and conformal structure and can be easily attached to different body parts. The battery-less operation of the device was enabled by NFC-based wireless power transmission and the compact antenna. Femtosecond laser ablation was employed to fabricate a highly compact and flexible NFC antenna. The proposed device demonstrated excellent operating characteristics with a limit of detection (LOD), limit of quantification (LOQ), and sensitivity of 24 μM, 74 μM, and 1.27 μA cm-2 mM-1, respectively. The response of the proposed sensor in sweat glucose detection and quantification was validated by nuclear magnetic resonance spectroscopy (NMR). Also, the device's capability in attachment to the body, sweat collection, and glucose measurement was demonstrated through in vitro and in vivo experiments, and satisfactory results were obtained.
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Affiliation(s)
- Hadi Mirzajani
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Taher Abbasiasl
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Fariborz Mirlou
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Emin Istif
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Mohammad Javad Bathaei
- Department of Biomedical Sciences and Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Çağdaş Dağ
- Department of Molecular Biology and Genetics, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey; Nanofabrication and Nanocharacterization Centre for Scientific and Technological Advanced Research, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey; Koç University İşBank Centre for Infectious Diseases, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Oğuzhan Deyneli
- Division of Endocrinology, Department of Internal Medicine, School of Medicine, Koç University Hospital, Topkapı Caddesi, Zeytinburnu, Istanbul, Turkey
| | - Dilek Yazıcı
- Division of Endocrinology, Department of Internal Medicine, School of Medicine, Koç University Hospital, Topkapı Caddesi, Zeytinburnu, Istanbul, Turkey
| | - Levent Beker
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey; Koç University Research Center for Translational Research (KUTTAM), Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey.
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9
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Mirzajani H, Mirlou F, Istif E, Singh R, Beker L. Powering smart contact lenses for continuous health monitoring: Recent advancements and future challenges. Biosens Bioelectron 2022; 197:113761. [PMID: 34800926 DOI: 10.1016/j.bios.2021.113761] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 10/15/2021] [Accepted: 10/29/2021] [Indexed: 12/16/2022]
Abstract
As the tear is noninvasively and continuously available, it has been turned into a convenient biological interface as a wearable medical device for out-of-hospital and self-monitoring applications. Recent progress in integrated circuits (ICs) and biosensors coupled with wireless data communication techniques have led to the implementation of smart contact lenses that can continuously sample tear fluid, analyze physiological conditions, and wirelessly transmit data to an electronic device such as smartphone, which can send data to relevant healthcare units. Continuous analyte monitoring is one of the significant characteristics of wearable biosensors. However, despite several advantages over other on-skin wearable medical devices, batteries cannot be incorporated on smart contact lenses for continuous electrical power supply due to the limited area. Herein, we review the progress of power delivery techniques of smart contact lenses for the first time. Different approaches, including wireless power transmission (WPT), biofuel cells, supercapacitors, flexible batteries, wired connections, and hybrid methods, are thoroughly discussed to understand the principles of self-sustainable contact lens biosensors comprehensively. Additionally, recent progress in contact lens biosensors is reviewed in detail, thereby providing the prospects for further developments of smart contact lenses as a common biosensing platform for various disease monitoring and diagnostic applications.
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Affiliation(s)
- Hadi Mirzajani
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Fariborz Mirlou
- Department of Electrical and Electronics Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Emin Istif
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Rahul Singh
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey
| | - Levent Beker
- Department of Mechanical Engineering, Koç University, Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey; Koç University Research Center for Translational Research (KUTTAM), Rumelifeneri Yolu, Sarıyer, Istanbul, 34450, Turkey.
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10
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Affiliation(s)
- Levent Beker
- Department of Mechanical Engineering, Koç University, Istanbul, Turkey.
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11
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You I, Mackanic DG, Matsuhisa N, Kang J, Kwon J, Beker L, Mun J, Suh W, Kim TY, Tok JBH, Bao Z, Jeong U. Artificial multimodal receptors based on ion relaxation dynamics. Science 2021; 370:961-965. [PMID: 33214277 DOI: 10.1126/science.aba5132] [Citation(s) in RCA: 155] [Impact Index Per Article: 51.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 09/24/2020] [Indexed: 12/13/2022]
Abstract
Human skin has different types of tactile receptors that can distinguish various mechanical stimuli from temperature. We present a deformable artificial multimodal ionic receptor that can differentiate thermal and mechanical information without signal interference. Two variables are derived from the analysis of the ion relaxation dynamics: the charge relaxation time as a strain-insensitive intrinsic variable to measure absolute temperature and the normalized capacitance as a temperature-insensitive extrinsic variable to measure strain. The artificial receptor with a simple electrode-electrolyte-electrode structure simultaneously detects temperature and strain by measuring the variables at only two measurement frequencies. The human skin-like multimodal receptor array, called multimodal ion-electronic skin (IEM-skin), provides real-time force directions and strain profiles in various tactile motions (shear, pinch, spread, torsion, and so on).
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Affiliation(s)
- Insang You
- Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.,Department of Chemical Engineering, Stanford University, Stanford, CA 94305-5025, USA.,Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - David G Mackanic
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305-5025, USA
| | - Naoji Matsuhisa
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305-5025, USA
| | - Jiheong Kang
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305-5025, USA
| | - Jimin Kwon
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Levent Beker
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305-5025, USA
| | - Jaewan Mun
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305-5025, USA
| | - Wonjeong Suh
- Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Tae Yeong Kim
- Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Jeffrey B-H Tok
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305-5025, USA
| | - Zhenan Bao
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305-5025, USA.
| | - Unyong Jeong
- Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.
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Singh R, Bathaei MJ, Istif E, Beker L. A Review of Bioresorbable Implantable Medical Devices: Materials, Fabrication, and Implementation. Adv Healthc Mater 2020; 9:e2000790. [PMID: 32790033 DOI: 10.1002/adhm.202000790] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/22/2020] [Indexed: 12/15/2022]
Abstract
Implantable medical devices (IMDs) are designed to sense specific parameters or stimulate organs and have been actively used for treatment and diagnosis of various diseases. IMDs are used for long-term disease screening or treatments and cannot be considered for short-term applications since patients need to go through a surgery for retrieval of the IMD. Advances in bioresorbable materials has led to the development of transient IMDs that can be resorbed by bodily fluids and disappear after a certain period. These devices are designed to be implanted in the adjacent of the targeted tissue for predetermined times with the aim of measurement of pressure, strain, or temperature, while the bioelectronic devices stimulate certain tissues. They enable opportunities for monitoring and treatment of acute diseases. To realize such transient and miniaturized devices, researchers utilize a variety of materials, novel fabrication methods, and device design strategies. This review discusses potential bioresorbable materials for each component in an IMD followed by programmable degradation and safety standards. Then, common fabrication methods for bioresorbable materials are introduced, along with challenges. The final section provides representative examples of bioresorbable IMDs for various applications with an emphasis on materials, device functionality, and fabrication methods.
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Affiliation(s)
- Rahul Singh
- Department of Mechanical Engineering Koç University Rumelifeneri Yolu, Sarıyer Istanbul 34450 Turkey
| | - Mohammad Javad Bathaei
- Department of Biomedical Sciences and Engineering Koç University Rumelifeneri Yolu, Sarıyer Istanbul 34450 Turkey
| | - Emin Istif
- Department of Mechanical Engineering Koç University Rumelifeneri Yolu, Sarıyer Istanbul 34450 Turkey
| | - Levent Beker
- Department of Mechanical Engineering Koç University Rumelifeneri Yolu, Sarıyer Istanbul 34450 Turkey
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13
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Beker L, Matsuhisa N, You I, Ruth SRA, Niu S, Foudeh A, Tok JBH, Chen X, Bao Z. A bioinspired stretchable membrane-based compliance sensor. Proc Natl Acad Sci U S A 2020; 117:11314-11320. [PMID: 32385155 PMCID: PMC7260970 DOI: 10.1073/pnas.1909532117] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Compliance sensation is a unique feature of the human skin that electronic devices could not mimic via compact and thin form-factor devices. Due to the complex nature of the sensing mechanism, up to now, only high-precision or bulky handheld devices have been used to measure compliance of materials. This also prevents the development of electronic skin that is fully capable of mimicking human skin. Here, we developed a thin sensor that consists of a strain sensor coupled to a pressure sensor and is capable of identifying compliance of touched materials. The sensor can be easily integrated into robotic systems due to its small form factor. Results showed that the sensor is capable of classifying compliance of materials with high sensitivity allowing materials with various compliance to be identified. We integrated the sensor to a robotic finger to demonstrate the capability of the sensor for robotics. Further, the arrayed sensor configuration allows a compliance mapping which can enable humanlike sensations to robotic systems when grasping objects composed of multiple materials of varying compliance. These highly tunable sensors enable robotic systems to handle more advanced and complicated tasks such as classifying touched materials.
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Affiliation(s)
- Levent Beker
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305
- Department of Mechanical Engineering, Koç University, Sariyer, Istanbul, 34450, Turkey
| | - Naoji Matsuhisa
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Insang You
- Department of Materials Science and Engineering, Pohang University of Science and Technology, 37673 Pohang, Gyeongbuk, Korea
| | | | - Simiao Niu
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305
| | - Amir Foudeh
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305
| | - Jeffrey B-H Tok
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305
| | - Xiaodong Chen
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Zhenan Bao
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305;
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14
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Oda H, Beker L, Kaizawa Y, Franklin A, Min JG, Leyden J, Wang Z, Chang J, Bao Z, Fox PM. A Novel Technology for Free Flap Monitoring: Pilot Study of a Wireless, Biodegradable Sensor. J Reconstr Microsurg 2019; 36:182-190. [PMID: 31675757 DOI: 10.1055/s-0039-1700539] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Accurate monitoring of free flap perfusion after complex reconstruction is critical for early recognition of flap compromise. Surgeons use a variety of subjective and objective measures to evaluate flap perfusion postoperatively. However, these measures have some limitations. We have developed a wireless, biodegradable, and flexible sensor that can be applied to real-time postoperative free flap monitoring. Here we assess the biocompatibility and function of our novel sensor. METHODS Seven Sprague-Dawley (SD) rats were used for biocompatibility studies. The sensor was implanted around the femoral artery near the inguinal ligament on one leg (implant side) and sham surgery was performed on the contralateral leg (control side). At 6 and 12 weeks, samples were harvested to assess the inflammation within and around the implant and artery. Two animals were used to assess sensor function. Sensor function was evaluated at implantation and 7 days after the implantation. Signal changes after venous occlusion were also assessed in an epigastric artery island flap model. RESULTS In biocompatibility studies, the diameter of the arterial lumen and intima thickness in the implant group were not significantly different than the control group at the 12-week time point. The number of CD-68 positive cells that infiltrated into the soft tissue, surrounding the femoral artery, was also not significantly different between groups at the 12-week time point. For sensor function, accurate signaling could be recorded at implantation and 7 days later. A change in arterial signal was noted immediately after venous occlusion in a flap model. CONCLUSION The novel wireless, biodegradable sensor presented here is biocompatible and capable of detecting arterial blood flow and venous occlusion with high sensitivity. This promising new technology could combat the complications of wired sensors, while improving the survival rate of flaps with vessel compromise due to its responsive nature.
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Affiliation(s)
- Hiroki Oda
- Department of Surgery, Division of Plastic and Reconstructive Surgery, Stanford University Medical Center, Palo Alto, California.,Division of Plastic and Reconstructive Surgery, Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| | - Levent Beker
- Department of Chemical Engineering, Stanford University, Stanford, California
| | - Yukitoshi Kaizawa
- Department of Surgery, Division of Plastic and Reconstructive Surgery, Stanford University Medical Center, Palo Alto, California.,Division of Plastic and Reconstructive Surgery, Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| | - Austin Franklin
- Department of Surgery, Division of Plastic and Reconstructive Surgery, Stanford University Medical Center, Palo Alto, California.,Division of Plastic and Reconstructive Surgery, Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| | - Jung Gi Min
- Department of Surgery, Division of Plastic and Reconstructive Surgery, Stanford University Medical Center, Palo Alto, California.,Division of Plastic and Reconstructive Surgery, Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| | - Jacinta Leyden
- Department of Surgery, Division of Plastic and Reconstructive Surgery, Stanford University Medical Center, Palo Alto, California.,Division of Plastic and Reconstructive Surgery, Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| | - Zhen Wang
- Department of Surgery, Division of Plastic and Reconstructive Surgery, Stanford University Medical Center, Palo Alto, California.,Division of Plastic and Reconstructive Surgery, Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| | - James Chang
- Department of Surgery, Division of Plastic and Reconstructive Surgery, Stanford University Medical Center, Palo Alto, California.,Division of Plastic and Reconstructive Surgery, Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| | - Zhenan Bao
- Department of Chemical Engineering, Stanford University, Stanford, California
| | - Paige M Fox
- Department of Surgery, Division of Plastic and Reconstructive Surgery, Stanford University Medical Center, Palo Alto, California.,Division of Plastic and Reconstructive Surgery, Veterans Affairs Palo Alto Health Care System, Palo Alto, California
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Feig VR, Tran H, Lee M, Liu K, Huang Z, Beker L, Mackanic DG, Bao Z. An Electrochemical Gelation Method for Patterning Conductive PEDOT:PSS Hydrogels. Adv Mater 2019; 31:e1902869. [PMID: 31414520 DOI: 10.1002/adma.201902869] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 07/28/2019] [Indexed: 05/20/2023]
Abstract
Due to their high water content and macroscopic connectivity, hydrogels made from the conducting polymer PEDOT:PSS are a promising platform from which to fabricate a wide range of porous conductive materials that are increasingly of interest in applications as varied as bioelectronics, regenerative medicine, and energy storage. Despite the promising properties of PEDOT:PSS-based porous materials, the ability to pattern PEDOT:PSS hydrogels is still required to enable their integration with multifunctional and multichannel electronic devices. In this work, a novel electrochemical gelation ("electrogelation") method is presented for rapidly patterning PEDOT:PSS hydrogels on any conductive template, including curved and 3D surfaces. High spatial resolution is achieved through use of a sacrificial metal layer to generate the hydrogel pattern, thereby enabling high-performance conducting hydrogels and aerogels with desirable material properties to be introduced into increasingly complex device architectures.
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Affiliation(s)
- Vivian Rachel Feig
- Department of Materials Science and Engineering, Stanford University, 443 Via Ortega, Room 328, Stanford, CA, 93405, USA
| | - Helen Tran
- Department of Chemical Engineering, Stanford University, 443 Via Ortega, Room 328, Stanford, CA, 93405, USA
| | - Minah Lee
- Center for Energy Storage Research, Clean Energy Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Korea
| | - Kathy Liu
- Department of Materials Science and Engineering, Stanford University, 443 Via Ortega, Room 328, Stanford, CA, 93405, USA
| | - Zhuojun Huang
- Department of Materials Science and Engineering, Stanford University, 443 Via Ortega, Room 328, Stanford, CA, 93405, USA
| | - Levent Beker
- Department of Mechanical Engineering, Koç University Rumelifeneri Yolu, Sarıyer, İstanbul, 34450, Turkey
| | - David G Mackanic
- Department of Chemical Engineering, Stanford University, 443 Via Ortega, Room 328, Stanford, CA, 93405, USA
| | - Zhenan Bao
- Department of Chemical Engineering, Stanford University, 443 Via Ortega, Room 328, Stanford, CA, 93405, USA
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Boutry CM, Beker L, Kaizawa Y, Vassos C, Tran H, Hinckley AC, Pfattner R, Niu S, Li J, Claverie J, Wang Z, Chang J, Fox PM, Bao Z. Biodegradable and flexible arterial-pulse sensor for the wireless monitoring of blood flow. Nat Biomed Eng 2019; 3:47-57. [DOI: 10.1038/s41551-018-0336-5] [Citation(s) in RCA: 371] [Impact Index Per Article: 74.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 11/27/2018] [Indexed: 12/20/2022]
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17
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Beker L, Benet A, Meybodi AT, Eovino B, Pisano AP, Lin L. Energy harvesting from cerebrospinal fluid pressure fluctuations for self-powered neural implants. Biomed Microdevices 2017; 19:32. [PMID: 28425028 DOI: 10.1007/s10544-017-0176-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this paper, a novel method to generate electrical energy by converting available mechanical energy from pressure fluctuations of the cerebrospinal fluid within lateral ventricles of the brain is presented. The generated electrical power can be supplied to the neural implants and either eliminate their battery need or extend the battery lifespan. A diaphragm type harvester comprised of piezoelectric material is utilized to convert the pressure fluctuations to electrical energy. The pressure fluctuations cause the diaphragm to bend, and the strained piezoelectric materials generate electricity. In the framework of this study, an energy harvesting structure having a diameter of 2.5 mm was designed and fabricated using microfabrication techniques. A 1:1 model of lateral ventricles was 3D-printed from raw MRI images to characterize the harvester. Experimental results show that a maximum power of 0.62 nW can be generated from the harvester under similar physical conditions in lateral ventricles which corresponds to energy density of 12.6 nW/cm2. Considering the available area within the lateral ventricles and the size of harvesters that can be built using microfabrication techniques it is possible to amplify to power up to 26 nW. As such, the idea of generating electrical energy by making use of pressure fluctuations within brain is demonstrated in this work via the 3D-printed model system.
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Affiliation(s)
- Levent Beker
- Department of Mechanical Engineering, and Berkeley Sensor Actuator Center, University of California, Berkeley, CA, USA.
| | - Arnau Benet
- Department of Neurological Surgery, University of California, San Francisco, CA, USA
| | - Ali Tayebi Meybodi
- Department of Neurological Surgery, University of California, San Francisco, CA, USA
| | - Ben Eovino
- Department of Mechanical Engineering, and Berkeley Sensor Actuator Center, University of California, Berkeley, CA, USA
| | - Albert P Pisano
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, CA, USA
| | - Liwei Lin
- Department of Mechanical Engineering, and Berkeley Sensor Actuator Center, University of California, Berkeley, CA, USA
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19
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Beker L. Food and nutrition services for children. Second in a series on age-specific competencies. Health Care Food Nutr Focus 1998; 14:4-8. [PMID: 10177991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Abstract
We compared standard chest physical therapy and postural drainage (CPT/PD) with a new airway clearance therapy called high-frequency chest wall oscillation (HFCWO) in a group of stable cystic fibrosis (CF) patients. In this crossover trial, 29 CF patients (15 males, 14 females), aged 7-47 years that met the inclusion criteria were randomly assigned to alternate CPT/PD and HFCWO, on a daily basis, over a 4 day period. Each patient received 2 days of each form of therapy; treatment frequency and the length of treatment were the same for both techniques. Expectorated secretions were collected during each 30 minute therapy session and for 15 minutes following treatment. The wet and dry weights of collected secretions were determined gravimetrically, and the therapy methods were compared. Significantly more sputum was expectorated during HFCWO than during CPT/PD as determined by both the wet (P < 0.001) and the dry (P < 0.01) measurements. This study suggests that HFCWO is at least as effective as manual CPT/PD in clearing secretions from the airways in patients with cystic fibrosis.
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Affiliation(s)
- J Kluft
- Department of Pulmonary Medicine, Children's National Medical Center, Washington, DC 20010, USA
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