A Thread/Fabric-Based Band as A Flexible and Wearable Microfluidic Device for Sweat Sensing and Monitoring

Lab on a Chip ◽  
2021 ◽  
Author(s):  
Zhiqi Zhao ◽  
Qiujin Li ◽  
Linna Chen ◽  
Yu Zhao ◽  
Jixian Gong ◽  
...  
Keyword(s):  
Microfluidic Device ◽  
Point Of Care ◽  
Monitoring Systems ◽  
Biological Analytes

Flexible biosensors for monitoring systems have emerged as a promising portable diagnostics platform due to their potential for in situ point-of-care (POC) analytic devices. Assessment of biological analytes in sweat...

scholarly journals Direct and rapid measurement of hydrogen peroxide in human blood using a microfluidic device

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
R. Gaikwad ◽  
P. R. Thangaraj ◽  
A. K. Sen
Keyword(s):  
Hydrogen Peroxide ◽  
Microfluidic Device ◽  
Human Blood ◽  
Blood Cells ◽  
Limit Of Detection ◽  
Point Of Care ◽  
Time Interval ◽  
Fluorescence Measurement ◽  
Rapid Measurement ◽  
Automated Method

AbstractThe levels of hydrogen peroxide ($${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 ) in human blood is of great relevance as it has emerged as an important signalling molecule in a variety of disease states. Fast and reliable measurement of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 levels in the blood, however, continues to remain a challenge. Herein we report an automated method employing a microfluidic device for direct and rapid measurement of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 in human blood based on laser-induced fluorescence measurement. Our study delineates the critical factors that affect measurement accuracy—we found blood cells and soluble proteins significantly alter the native $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 levels in the time interval between sample withdrawal and detection. We show that separation of blood cells and subsequent dilution of the plasma with a buffer at a ratio of 1:6 inhibits the above effect, leading to reliable measurements. We demonstrate rapid measurement of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 in plasma in the concentration range of 0–49 µM, offering a limit of detection of 0.05 µM, a sensitivity of 0.60 µM−1, and detection time of 15 min; the device is amenable to the real-time measurement of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 in the patient’s blood. Using the linear correlation obtained with known quantities of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 , the endogenous $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 concentration in the blood of healthy individuals is found to be in the range of 0.8–6 µM. The availability of this device at the point of care will have relevance in understanding the role of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 in health and disease.

Simulation at the point of care: Reduced-cost, in situ training via a mobile cart

2009 ◽  
Vol 10 (2) ◽  
pp. 176-181 ◽  
Author(s):  
Peter H. Weinstock ◽  
Liana J. Kappus ◽  
Alexander Garden ◽  
Jeffrey P. Burns
Keyword(s):  
Point Of Care ◽  
In Situ Training

scholarly journals Adenosine Triphosphate Measurement in Deep Sea Using a Microfluidic Device

Micromachines ◽  
2018 ◽  
Vol 9 (8) ◽  
pp. 370 ◽  
Author(s):  
Tatsuhiro Fukuba ◽  
Takuroh Noguchi ◽  
Kei Okamura ◽  
Teruo Fujii
Keyword(s):  
Adenosine Triphosphate ◽  
Microfluidic Device ◽  
Deep Sea ◽  
Temperature Sensor ◽  
Biochemical Parameter ◽  
Underwater Vehicle ◽  
Luciferase Assay ◽  
Bioluminescence Intensity

Total ATP (adenosine triphosphate) concentration is a useful biochemical parameter for detecting microbial biomass or biogeochemical activity anomalies in the natural environment. In this study, we describe the development and evaluation of a new version of in situ ATP analyzer improved for the continuous and quantitative determination of ATP in submarine environments. We integrated a transparent microfluidic device containing a microchannel for cell lysis and a channel for the bioluminescence L–L (luciferin–luciferase) assay with a miniature pumping unit and a photometry module for the measurement of the bioluminescence intensity. A heater and a temperature sensor were also included in the system to maintain an optimal temperature for the L–L reaction. In this study, the analyzer was evaluated in deep sea environments, reaching a depth of 200 m using a remotely operated underwater vehicle. We show that the ATP analyzer successfully operated in the deep-sea environment and accurately quantified total ATP within the concentration lower than 5 × 10−11 M.

In situ fabrication of a microfluidic device for immobilised metal affinity sensing

2012 ◽  
Vol 29 (4) ◽  
pp. 494-501 ◽  
Author(s):  
Abhishek G. Deshpande ◽  
Nicholas J. Darton ◽  
Kamran Yunus ◽  
Adrian C. Fisher ◽  
Nigel K.H. Slater
Keyword(s):  
Microfluidic Device ◽  
Metal Affinity ◽  
In Situ Fabrication

Laboratory Experimentations for New Hydrothermal Monitoring Systems Using ADCPs

2013 ◽  
Author(s):  
Kanae Komaki ◽  
Mitsuru Shimazu ◽  
Shunsuke Kondo ◽  
Yosuke Onishi ◽  
Satoshi Furuta ◽  
...  
Keyword(s):  
Environmental Impact ◽  
Deep Ocean ◽  
Monitoring Systems ◽  
Echo Intensity ◽  
In Situ Data ◽  
Environmental Impact Assessments ◽  
Suspended Matters ◽  
Water Tanks ◽  
Ocean Mining

Deep ocean mining in a hydrothermal area needs careful environmental impact assessments in terms of preservation and mitigation of biodiversity. The General Environmental Technos Co. Ltd., or KANSO TECHNOS, for short, has participated in environmental impact assessments in hydrothermal areas in the Izu-Ogasawara and the East China Sea areas (Ishida et al., 2011). Through the experience, we suggest a method of using acoustic systems such as acoustic Doppler current profilers (ADCPs) for monitoring of suspended matters and benthos in hydrothermal areas. Thus, we try to do in-situ observations, called Tow-yo (or Towing) observations with ADCPs (Komaki and Ura, 2009; Komaki et al., 2010). This system has a great advantage in enabling the measurement of great environmental factors, echo intensity and current velocity in a large range. To confirm exactly what the substances are and how large they are from the measured echo intensity data, we tried laboratory experiments in water tanks with echo sounders and turbidity sensors. These results will finally be integrated in a simulation model to predict substances from in-situ data in deep water for future monitoring systems.

Comparison of two glucose-monitoring systems for use in horses

2022 ◽  
pp. 1-7
Author(s):  
Caitlin E. Malik ◽  
David M. Wong ◽  
Katarzyna A. Dembek ◽  
Katherine E. Wilson
Keyword(s):  
Blood Glucose ◽  
Blood Glucose Concentration ◽  
Point Of Care ◽  
Glucose Monitoring ◽  
Glucose Absorption ◽  
Monitoring Systems ◽  
Oral Glucose ◽  
Clinically Normal ◽  
Freestyle Libre ◽  
Interstitial Glucose

Abstract OBJECTIVE To determine the accuracy of 2 interstitial glucose-monitoring systems (GMSs) for use in horses compared with a point-of-care (POC) glucometer and standard laboratory enzymatic chemistry method (CHEM). ANIMALS 8 clinically normal adult horses. PROCEDURES One of each GMS device (Dexcom G6 and Freestyle Libre 14-day) was placed on each horse, and blood glucose concentration was measured via POC and CHEM at 33 time points and compared with simultaneous GMS readings. An oral glucose absorption test (OGAT) was performed on day 2, and glucose concentrations were measured and compared. RESULTS Glucose concentrations were significantly correlated with one another between all devices on days 1 to 5. Acceptable agreement was observed between Dexcom G6 and Freestyle Libre 14-day when compared with CHEM on days 1, 3, 4, and 5 with a combined mean bias of 10.45 mg/dL and 1.53 mg/dL, respectively. During dextrose-induced hyperglycemia on day 2, mean bias values for Dexcom G6 (10.49 mg/dL) and FreeStyle Libre 14-day (0.34 mg/dL) showed good agreement with CHEM. CLINICAL RELEVANCE Serial blood glucose measurements are used to diagnose or monitor a variety of conditions in equine medicine; advances in near-continuous interstitial glucose monitoring allow for minimally invasive glucose assessment, thereby reducing stress and discomfort to patients. Data from this study support the use of the Dexcom G6 and Freestyle Libre 14-day interstitial glucose-monitoring systems to estimate blood glucose concentrations in horses.

scholarly journals Electroosmotic flow driven microfluidic device for bacteria isolation using magnetic microbeads

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Samuel Miller ◽  
Alison A. Weiss ◽  
William R. Heineman ◽  
Rupak K. Banerjee
Keyword(s):  
Microfluidic Device ◽  
Electroosmotic Flow ◽  
Point Of Care ◽  
Food Poisoning ◽  
Fluorescent Intensity ◽  
Magnetic Microbeads ◽  
E Coli ◽  
Detection Assay ◽  
Flow Capture ◽  
Improved Performance

Abstract The presence of bacterial pathogens in water can lead to severe complications such as infection and food poisoning. This research proposes a point-of-care electroosmotic flow driven microfluidic device for rapid isolation and detection of E. coli in buffered solution (phosphate buffered saline solution). Fluorescent E. coli bound to magnetic microbeads were driven through the microfluidic device using both constant forward flow and periodic flow switching at concentrations ranging from 2 × 105 to 4 × 107 bacteria/mL. A calibration curve of fluorescent intensity as a function of bacteria concentration was created using both constant and switching flow, showing an increase in captured fluorescent pixel count as concentration increases. In addition, the use of the flow switching resulted in a significant increase in the capture efficiency of E. coli, with capture efficiencies up to 83% ± 8% as compared to the constant flow capture efficiencies (up to 39% ± 11%), with a sample size of 3 µL. These results demonstrate the improved performance associated with the use of the electroosmotic flow switching system in a point-of-care bacterial detection assay.

scholarly journals Comparative evaluation of in situ stress monitoring with Rayleigh waves

2018 ◽  
Vol 18 (1) ◽  
pp. 205-215 ◽  
Author(s):  
James Martin Hughes ◽  
James Vidler ◽  
Ching-Tai Ng ◽  
Aditya Khanna ◽  
Munawwar Mohabuth ◽  
...  
Keyword(s):  
Rayleigh Wave ◽  
Harmonic Generation ◽  
Health Monitoring ◽  
Rayleigh Waves ◽  
Second Harmonic ◽  
Monitoring Systems ◽  
Stress Monitoring ◽  
Bulk Waves ◽  
Health Monitoring Systems

The in situ monitoring of stresses provides a crucial input for residual life prognosis and is an integral part of structural health monitoring systems. Stress monitoring is generally achieved by utilising the acoustoelastic effect, which relates the speed of elastic waves in a solid, typically longitudinal and shear waves, to the stress state. A major shortcoming of methods based on the acoustoelastic effect is their poor sensitivity. Another shortcoming of acoustoelastic methods is associated with the rapid attenuation of bulk waves in the propagation medium, requiring the use of dense sensor networks. The purpose of this article is twofold: to demonstrate the application of Rayleigh (guided) waves rather than bulk waves towards stress monitoring based on acoustoelasticity, and to propose a new method for stress monitoring based on the rate of accumulation of the second harmonic of large-amplitude Rayleigh waves. An experimental study is conducted using the cross-correlation signal processing technique to increase the accuracy of determining Rayleigh wave speeds when compared with traditional methods. This demonstrates the feasibility of Rayleigh wave–based acoustoelastic structural health monitoring systems, which could easily be integrated with existing sensor networks. Second harmonic generation is then investigated to demonstrate the sensitivity of higher order harmonics to stress-induced nonlinearities. The outcomes of this study demonstrate that the sensitivity of the new second harmonic generation method is several orders of magnitude greater than the acoustoelastic method, making the proposed method more suitable for development for online stress monitoring of in-service structures.

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