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Upadhyay S, Kumar A, Srivastava M, Srivastava A, Dwivedi A, Singh RK, Srivastava SK. Recent advancements of smartphone-based sensing technology for diagnosis, food safety analysis, and environmental monitoring. Talanta 2024; 275:126080. [PMID: 38615454 DOI: 10.1016/j.talanta.2024.126080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 04/04/2024] [Accepted: 04/07/2024] [Indexed: 04/16/2024]
Abstract
The emergence of computationally powerful smartphones, relatively affordable high-resolution camera, drones, and robotic sensors have ushered in a new age of advanced sensible monitoring tools. The present review article investigates the burgeoning smartphone-based sensing paradigms, including surface plasmon resonance (SPR) biosensors, electrochemical biosensors, colorimetric biosensors, and other innovations for modern healthcare. Despite the significant advancements, there are still scarcity of commercially available smart biosensors and hence need to accelerate the rates of technology transfer, application, and user acceptability. The application/necessity of smartphone-based biosensors for Point of Care (POC) testing, such as prognosis, self-diagnosis, monitoring, and treatment selection, have brought remarkable innovations which eventually eliminate sample transportation, sample processing time, and result in rapid findings. Additionally, it articulates recent advances in various smartphone-based multiplexed bio sensors as affordable and portable sensing platforms for point-of-care devices, together with statistics for point-of-care health monitoring and their prospective commercial viability.
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Affiliation(s)
- Satyam Upadhyay
- Department of Physics, Institute of Science, Banaras Hindu University, Varanasi, 221005, India
| | - Anil Kumar
- Department of Physics, Institute of Science, Banaras Hindu University, Varanasi, 221005, India
| | - Monika Srivastava
- School of Materials Science and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Amit Srivastava
- Department of Physics TDPG College, VBS Purvanchal University, Jaunpur, 222001, India
| | - Arpita Dwivedi
- Department of Physics, Institute of Science, Banaras Hindu University, Varanasi, 221005, India
| | - Rajesh Kumar Singh
- School of Physical and Material Sciences, Central University of Himachal Pradesh, Dharamshala, Kangra, 176215, India
| | - S K Srivastava
- Department of Physics, Institute of Science, Banaras Hindu University, Varanasi, 221005, India.
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Lu X, Bao J, Wei Y, Zhang S, Liu W, Wu J. Emerging Roles of Microrobots for Enhancing the Sensitivity of Biosensors. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2902. [PMID: 37947746 PMCID: PMC10650336 DOI: 10.3390/nano13212902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/29/2023] [Accepted: 10/30/2023] [Indexed: 11/12/2023]
Abstract
To meet the increasing needs of point-of-care testing in clinical diagnosis and daily health monitoring, numerous cutting-edge techniques have emerged to upgrade current portable biosensors with higher sensitivity, smaller size, and better intelligence. In particular, due to the controlled locomotion characteristics in the micro/nano scale, microrobots can effectively enhance the sensitivity of biosensors by disrupting conventional passive diffusion into an active enrichment during the test. In addition, microrobots are ideal to create biosensors with functions of on-demand delivery, transportation, and multi-objective detections with the capability of actively controlled motion. In this review, five types of portable biosensors and their integration with microrobots are critically introduced. Microrobots can enhance the detection signal in fluorescence intensity and surface-enhanced Raman scattering detection via the active enrichment. The existence and quantity of detection substances also affect the motion state of microrobots for the locomotion-based detection. In addition, microrobots realize the indirect detection of the bio-molecules by functionalizing their surfaces in the electrochemical current and electrochemical impedance spectroscopy detections. We pay a special focus on the roles of microrobots with active locomotion to enhance the detection performance of portable sensors. At last, perspectives and future trends of microrobots in biosensing are also discussed.
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Affiliation(s)
- Xiaolong Lu
- State Key Laboratory of Mechanics and Control for Aerospace Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; (J.B.); (Y.W.); (S.Z.)
- Biomedical Engineering Fusion Laboratory, The Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing 211100, China
| | - Jinhui Bao
- State Key Laboratory of Mechanics and Control for Aerospace Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; (J.B.); (Y.W.); (S.Z.)
- Biomedical Engineering Fusion Laboratory, The Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing 211100, China
| | - Ying Wei
- State Key Laboratory of Mechanics and Control for Aerospace Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; (J.B.); (Y.W.); (S.Z.)
- Biomedical Engineering Fusion Laboratory, The Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing 211100, China
| | - Shuting Zhang
- State Key Laboratory of Mechanics and Control for Aerospace Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; (J.B.); (Y.W.); (S.Z.)
| | - Wenjuan Liu
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Jie Wu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China;
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Beduk T, Beduk D, Hasan MR, Guler Celik E, Kosel J, Narang J, Salama KN, Timur S. Smartphone-Based Multiplexed Biosensing Tools for Health Monitoring. BIOSENSORS 2022; 12:bios12080583. [PMID: 36004979 PMCID: PMC9406027 DOI: 10.3390/bios12080583] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 07/25/2022] [Accepted: 07/26/2022] [Indexed: 05/24/2023]
Abstract
Many emerging technologies have the potential to improve health care by providing more personalized approaches or early diagnostic methods. In this review, we cover smartphone-based multiplexed sensors as affordable and portable sensing platforms for point-of-care devices. Multiplexing has been gaining attention recently for clinical diagnosis considering certain diseases require analysis of complex biological networks instead of single-marker analysis. Smartphones offer tremendous possibilities for on-site detection analysis due to their portability, high accessibility, fast sample processing, and robust imaging capabilities. Straightforward digital analysis and convenient user interfaces support networked health care systems and individualized health monitoring. Detailed biomarker profiling provides fast and accurate analysis for disease diagnosis for limited sample volume collection. Here, multiplexed smartphone-based assays with optical and electrochemical components are covered. Possible wireless or wired communication actuators and portable and wearable sensing integration for various sensing applications are discussed. The crucial features and the weaknesses of these devices are critically evaluated.
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Affiliation(s)
- Tutku Beduk
- Silicon Austria Labs GmbH: Sensor Systems, 9524 Villach, Austria;
| | - Duygu Beduk
- Central Research Test and Analysis Laboratory Application and Research Center, Ege University, 35100 Izmir, Turkey;
| | - Mohd Rahil Hasan
- Department of Biotechnology, Jamia Hamdard, New Delhi 110062, India; (M.R.H.); (J.N.)
| | - Emine Guler Celik
- Department of Bioengineering, Faculty of Engineering, Ege University, 35100 Izmir, Turkey;
| | - Jurgen Kosel
- Silicon Austria Labs GmbH: Sensor Systems, 9524 Villach, Austria;
| | - Jagriti Narang
- Department of Biotechnology, Jamia Hamdard, New Delhi 110062, India; (M.R.H.); (J.N.)
| | - Khaled Nabil Salama
- Sensors Lab, Advanced Membranes and Porous Materials Center, Computer, Electrical and Mathematical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia;
| | - Suna Timur
- Central Research Test and Analysis Laboratory Application and Research Center, Ege University, 35100 Izmir, Turkey;
- Department of Biochemistry, Faculty of Science, Ege University, 35100 Izmir, Turkey
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Chung S, Bode L, Hall DA. Point-of-care human milk testing for maternal secretor status. Anal Bioanal Chem 2021; 414:3187-3196. [PMID: 34741182 PMCID: PMC8956550 DOI: 10.1007/s00216-021-03697-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/21/2021] [Accepted: 09/24/2021] [Indexed: 11/27/2022]
Abstract
We present an electrochemical impedimetric-based biosensor for monitoring the variation in human milk oligosaccharide (HMO) composition. 2′-Fucosyllactose (2’FL) is an HMO associated with infant growth, cognitive development, and protection from infectious diarrhea, one of the major causes of infant death worldwide. Due to genetic variation, the milk of some women (non-secretors) contains no or very little 2′FL with potential implications for infant health and development. However, there is currently no technology to analyze the presence and concentration of HMOs in human milk at the point-of-care (POC). The lack of such technology represents a major impediment to advancing human milk research and improving maternal-infant health. Towards this unmet need, we report an impedimetric assay for HMOs with an α-1,2 linkage, the most abundant of which is 2′FL. The sensor uses a lectin for affinity, specifically Ulex europaeusagglutininI (UEA), with electrochemical readout. In spiked studies, the sensor exhibited a high degree of linearity (R2 = 0.991) over 0.5 to 3.0 μM with a 330-nM detection limit. The sensor performance was clinically validated using banked human milk samples and correctly identified all secretor vs. non-secretor samples. Furthermore, despite the short 35-min assay time and low sample volume (25 μL), the assay was highly correlated with HPLC measurements. This bedside human milk testing assay enables POC, “sample-to-answer” quantitative HMO measurement, and will be a valuable tool to assess milk composition.
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Affiliation(s)
- Saeromi Chung
- Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Lars Bode
- Department of Pediatrics, University of California San Diego, La Jolla, CA, 92093, USA
- Mother-Milk-Infant Center of Research Excellence (MOMI CORE), University of California San Diego, La Jolla, CA, 92093, USA
| | - Drew A Hall
- Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, CA, 92093, USA.
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA.
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Dieujuste D, Qiang Y, Du E. A portable impedance microflow cytometer for measuring cellular response to hypoxia. Biotechnol Bioeng 2021; 118:4041-4051. [PMID: 34232511 DOI: 10.1002/bit.27879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 06/04/2021] [Accepted: 06/24/2021] [Indexed: 01/02/2023]
Abstract
This article presents the development and testing of a low-cost (<$60), portable, electrical impedance-based microflow cytometer for single-cell analysis under a controlled oxygen microenvironment. The system is based on an AD5933 impedance analyzer chip, a microfluidic chip, and an Arduino microcontroller operated by a custom Android application. A representative case study on human red blood cells (RBCs) affected by sickle cell disease is conducted to demonstrate the capability of the cytometry system. Impedance values of sickle blood samples exhibit remarkable deviations from the common reference line obtained from two normal blood samples. Such deviation is quantified by a conformity score, which allows for the measurement of intrapatient and interpatient variations of sickle cell disease. A low conformity score under oxygenated conditions or drastically different conformity scores between oxygenated and deoxygenated conditions can be used to differentiate a sickle blood sample from normal. Furthermore, an equivalent circuit model of a suspended biological cell is used to interpret the electrical impedance of single flowing RBCs. In response to hypoxia treatment, all samples, regardless of disease state, exhibit significant changes in at least one single-cell electrical property, that is, cytoplasmic resistance and membrane capacitance. The overall response to hypoxia is less in normal cells than those affected by sickle cell disease, where the change in membrane capacitance varies from -23% to seven times as compared with -17% in normal cells. The results reported in this article suggest that the developed method of testing demonstrates the potential application for a low-cost screening technique for sickle cell disease and other diseases in the field and low-resource settings. The developed system and methodology can be extended to analyze cellular response to hypoxia in other cell types.
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Affiliation(s)
- Darryl Dieujuste
- Department of Ocean and Mechanical Engineering, and the Department of Biological Sciences, Florida Atlantic University, Boca Raton, Florida, USA
| | - Yuhao Qiang
- Department of Ocean and Mechanical Engineering, and the Department of Biological Sciences, Florida Atlantic University, Boca Raton, Florida, USA
| | - E Du
- Department of Ocean and Mechanical Engineering, and the Department of Biological Sciences, Florida Atlantic University, Boca Raton, Florida, USA
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Huang CC, Ray P, Chan M, Zhou X, Hall DA. An aptamer-based magnetic flow cytometer using matched filtering. Biosens Bioelectron 2020; 169:112362. [PMID: 32911314 DOI: 10.1016/j.bios.2020.112362] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/26/2020] [Accepted: 06/03/2020] [Indexed: 01/13/2023]
Abstract
Facing unprecedented population-ageing, the management of noncommunicable diseases (NCDs) urgently needs a point-of-care (PoC) testing infrastructure. Magnetic flow cytometers are one such solution for rapid cancer cellular detection in a PoC setting. In this work, we report a giant magnetoresistive spin-valve (GMR SV) biosensor array with a multi-stripe sensor geometry and matched filtering to improve detection accuracy without compromising throughput. The carefully designed sensor geometry generates a characteristic signature when cells labeled with magnetic nanoparticles (MNPs) pass by thus enabling multi-parametric measurement like optical flow cytometers (FCMs). Enumeration and multi-parametric information were successfully measured across two decades of throughput (37 - 2730 cells/min). 10-μm polymer microspheres were used as a biomimetic model where MNPs and MNP-decorated polymer conjugates were flown over the GMR SV sensor array and detected with a signal-to-noise ratio (SNR) as low as 2.5 dB due to the processing gain afforded by the matched filtering. The performance was compared against optical observation, exhibiting a 92% detection efficiency. The system achieved a 95% counting accuracy for biomimetic models and 98% for aptamer-based pancreatic cancer cell detection. This system demonstrates the ability to perform reliable flow cytometry toward PoC diagnostics to benefit NCD control plans.
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Affiliation(s)
- Chih-Cheng Huang
- Materials Science and Engineering Program, University of California - San Diego, La Jolla, CA, 92093, USA
| | - Partha Ray
- Division of Surgical Oncology, Department of Surgery, Moores Cancer Center, UC San Diego Health, La Jolla, CA, 92093, USA
| | - Matthew Chan
- Department of Electrical and Computer Engineering, University of California - San Diego, La Jolla, CA, 92093, USA
| | - Xiahan Zhou
- Department of Electrical and Computer Engineering, University of California - San Diego, La Jolla, CA, 92093, USA
| | - Drew A Hall
- Department of Electrical and Computer Engineering, University of California - San Diego, La Jolla, CA, 92093, USA; Department of Bioengineering, University of California - San Diego, La Jolla, CA, 92093, USA.
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Low-Cost, Compact, and Rapid Bio-Impedance Spectrometer with Real-Time Bode and Nyquist Plots. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10030878] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Bioelectric impedance spectroscopy (BIS) has been widely used to study the electrical properties of biological tissue based on the characteristics of the complex electrical impedance dispersions. One of the problems in using the BIS method is the length of time required for the data acquisition process and possibly data analysis as well. In this research, a compact and work rapidly BIS instrumentation system has been developed at a low cost. It is designed to work in the frequency range of 100 Hz to 100 kHz, which is generally used in the fields of biophysics and medical physics. The BIS instrumentation system is built using several integrated modules. The modules are an AC current source to produce a selectable injection current; a data acquisition system to measure voltage, current, and phase difference rapidly and simultaneously; and software to calculate and display measurement results in the form of Bode and Nyquist plots in real time. The developed BIS system has been validated using a simple RC circuit as the sample being tested. The average time needed in the process of data acquisition and analysis until the formation of impedance dispersion curves in the form of Bode and Nyquist plots, for 54 sample frequencies, is less than one minute. The system is able to identify R and C values of the sample with a maximum error of 1.5%. In addition, some simple application examples are also presented in this paper.
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Ghosh S, Aggarwal K, U. VT, Nguyen T, Han J, Ahn CH. A new microchannel capillary flow assay (MCFA) platform with lyophilized chemiluminescence reagents for a smartphone-based POCT detecting malaria. MICROSYSTEMS & NANOENGINEERING 2020; 6:5. [PMID: 34567620 PMCID: PMC8433401 DOI: 10.1038/s41378-019-0108-8] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 07/30/2019] [Accepted: 09/17/2019] [Indexed: 05/06/2023]
Abstract
There has been a considerable development in microfluidic based immunodiagnostics over the past few years which has greatly favored the growth of novel point-of-care-testing (POCT). However, the realization of an inexpensive, low-power POCT needs cheap and disposable microfluidic devices that can perform autonomously with minimum user intervention. This work, for the first time, reports the development of a new microchannel capillary flow assay (MCFA) platform that can perform chemiluminescence based ELISA with lyophilized chemiluminescent reagents. This new MCFA platform exploits the ultra-high sensitivity of chemiluminescent detection while eliminating the shortcomings associated with liquid reagent handling, control of assay sequence and user intervention. The functionally designed microchannels along with adequate hydrophilicity produce a sequential flow of assay reagents and autonomously performs the ultra-high sensitive chemiluminescence based ELISA for the detection of malaria biomarker such as PfHRP2. The MCFA platform with no external flow control and simple chemiluminescence detection can easily communicate with smartphone via USB-OTG port using a custom-designed optical detector. The use of the smartphone for display, data transfer, storage and analysis, as well as the source of power allows the development of a smartphone based POCT analyzer for disease diagnostics. This paper reports a limit of detection (LOD) of 8 ng/mL by the smartphone analyzer which is sensitive enough to detect active malarial infection. The MCFA platform developed with the smartphone analyzer can be easily customized for different biomarkers, so a hand-held POCT for various infectious diseases can be envisaged with full networking capability at low cost.
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Affiliation(s)
- Sthitodhi Ghosh
- Department of Electrical Engineering and Computer Science, Microsystems and BioMEMS Laboratory, University of Cincinnati, Cincinnati, OH 45221 USA
| | - Kashish Aggarwal
- Department of Electrical Engineering and Computer Science, Microsystems and BioMEMS Laboratory, University of Cincinnati, Cincinnati, OH 45221 USA
| | - Vinitha T. U.
- Department of Electrical Engineering and Computer Science, Microsystems and BioMEMS Laboratory, University of Cincinnati, Cincinnati, OH 45221 USA
| | - Thinh Nguyen
- Department of Electrical Engineering and Computer Science, Microsystems and BioMEMS Laboratory, University of Cincinnati, Cincinnati, OH 45221 USA
| | - Jungyoup Han
- Mico BioMed USA Inc., 10999 Reed Hartman Highway, STE 309C, Cincinnati, OH 45242 USA
| | - Chong H. Ahn
- Department of Electrical Engineering and Computer Science, Microsystems and BioMEMS Laboratory, University of Cincinnati, Cincinnati, OH 45221 USA
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Sawhney MA, Conlan RS. POISED-5, a portable on-board electrochemical impedance spectroscopy biomarker analysis device. Biomed Microdevices 2019; 21:70. [PMID: 31273464 PMCID: PMC6609592 DOI: 10.1007/s10544-019-0406-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Point-of-care medical devices offer the potential for rapid biomarker detection and reporting of medical conditions, thereby bypassing the requirements for offline clinical laboratory facilities in many cases. Label-free electrochemical techniques are suitable for use in handheld diagnostic devices due the inherent electronic detection modality and low requirement for processing reagents. While electrochemical impedance sensing is widely used in tissue analysis such as body composition measurement, its use in point-of-care patient testing is yet to be widely adopted. Here we have considered a number of issues currently limiting the translation of electrochemical impedance sensing into clinical biosensor devices. Specifically, we have addressed the current requirement for these sensors to be connected to an external processor by applying a minimum number of frequencies required for optimized biomarker detection, and subsequently delivering analytics within the measurement device. The POISED-5 device was evaluated using a sensor for the ovarian cancer biomarker cancer antigen 125 (CA125), demonstrating performance comparable to standard laboratory equipment, with direct interpretation of response signal amplitude substituting traditional impedance component calculation and model fitting.
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Affiliation(s)
- M. Anne Sawhney
- Swansea University Medical School, Singleton Park, Swansea, SA2 8PP UK
- Centre for NanoHealth, Swansea University, Singleton Park, Swansea, SA2 8PP UK
| | - R. S. Conlan
- Swansea University Medical School, Singleton Park, Swansea, SA2 8PP UK
- Centre for NanoHealth, Swansea University, Singleton Park, Swansea, SA2 8PP UK
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Affiliation(s)
- Alexander C. Sun
- Electrical and Computer Engineering; University of California in; San Diego, La Jolla, CA
| | - Drew A. Hall
- Electrical and Computer Engineering; University of California in; San Diego, La Jolla, CA
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Phelps T, Hall DA. Development of a smartphone-based pulse oximeter with adaptive SNR/power balancing. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2017; 2017:3297-3300. [PMID: 29060602 DOI: 10.1109/embc.2017.8037561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Millions worldwide suffer from diseases that exhibit early warnings signs that can be detected by standard clinical-grade diagnostic tools. Unfortunately, such tools are often prohibitively expensive to the developing world leading to inadequate healthcare and high mortality rates. To address this problem, a smartphone-based pulse oximeter is presented that interfaces with the phone through the audio jack, enabling point-of-care measurements of heart rate (HR) and oxygen saturation (SpO2). The device is designed to utilize existing phone resources (e.g., the processor, battery, and memory) resulting in a more portable and inexpensive diagnostic tool than standalone equivalents. By adaptively tuning the LED driving signal, the device is less dependent on phone-specific audio jack properties than prior audio jack-based work making it universally compatible with all smartphones. We demonstrate that the pulse oximeter can adaptively optimize the signal-to-noise ratio (SNR) within the power constraints of a mobile phone (<; 10mW) while maintaining high accuracy (HR error <; 3.4% and SpO2 error <; 3.7%) against a clinical grade instrument.
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Xie P, Cao X, Lin Z, Javanmard M. Top-down fabrication meets bottom-up synthesis for nanoelectronic barcoding of microparticles. LAB ON A CHIP 2017; 17:1939-1947. [PMID: 28470316 DOI: 10.1039/c7lc00035a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Traditional optical and plasmonic techniques for barcoding of micro-particles for multiplexed bioassays are generally high in throughput, however bulky instrumentation is often required for performing readout. Electrical impedance based detection allows for ultra-compact instrumentation footprint necessary for wearable devices, however to date, the lack of ability to electronically barcode micro-particles has been a long standing bottleneck towards enabling multiplexed electronic biomarker assays. Nanoelectronic barcoding, which to the best of our knowledge is the first impedance based solution for micro-particle barcoding, works by forming tunable nano-capacitors on the surface of micro-spheres, effectively modulating the frequency dependent dielectric properties of the spheres allowing one bead barcode to be distinguished from another. Nanoelectronic barcoding uses a well-known, but unexplored electromagnetic phenomenon of micro-particles: the Clausius-Mossotti (CM) factor spectrum of a Janus particle (JP) shifts depending on the zeta (wall) potential of the metallic half of the microsphere, and the fact that the complex impedance spectrum of a particle directly corresponds to the CM factor spectrum. A one-to-one correspondence will be established between each biomarker and the corresponding engineered microsphere. This transformative new method for barcoding will enable a new class of handheld and wearable biosensors capable of multiplexed continuous temporal bio-monitoring. The proposed nano-electronically barcoded particles utilize both bottom-up synthesis and top-down fabrication to enable precisely engineered frequency dependent dielectric signatures. Multi-frequency lock-in measurements of the complex impedance, in conjunction with multi-variate analysis of impedance data, allows for particle differentiation using a fully functional ultra-compact electronic detector.
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Affiliation(s)
- Pengfei Xie
- Department of Electrical and Computer Engineering, Rutgers University, USA.
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