scholarly journals Design and Fabrication of Capillary-Driven Flow Device for Point-Of-Care Diagnostics

Biosensors ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 39 ◽  
Author(s):  
Sammer-ul Hassan ◽  
Xunli Zhang
Keyword(s):  
Point Of Care ◽  
Capillary Action ◽  
Point Of Care Diagnostics ◽  
Flow Device ◽  
Working Principle ◽  
Complex Fluid

Point-of-care (POC) diagnostics enables the diagnosis and monitoring of patients from the clinic or their home. Ideally, POC devices should be compact, portable and operatable without the requirement of expertise or complex fluid mechanical controls. This paper showcases a chip-and-dip device, which works on the principle of capillary-driven flow microfluidics and allows analytes’ detection by multiple microchannels in a single microchip via smartphone imaging. The chip-and-dip device, fabricated with inexpensive materials, works by simply dipping the reagents-coated microchip consisting of microchannels into a fluidic sample. The sample is loaded into the microchannels via capillary action and reacts with the reagents to produce a colourimetric signal. Unlike dipstick tests, this device allows the loading of bacterial/pathogenic samples for antimicrobial testing. A single device can be coated with multiple reagents, and more analytes can be detected in one sample. This platform could be used for a wide variety of assays. Here, we show the design, fabrication and working principle of the chip-and-dip flow device along with a specific application consisting in the determination of β-lactamase activity and cortisol. The simplicity, robustness and multiplexing capability of the chip-and-dip device will allow it to be used for POC diagnostics.

scholarly journals Current Nucleic Acid Extraction Methods and Their Implications to Point-of-Care Diagnostics

2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Nasir Ali ◽  
Rita de Cássia Pontello Rampazzo ◽  
Alexandre Dias Tavares Costa ◽  
Marco Aurelio Krieger
Keyword(s):  
Nucleic Acid ◽  
Extraction Method ◽  
Point Of Care ◽  
Extraction Methods ◽  
Vital Role ◽  
Acid Extraction ◽  
Nucleic Acid Extraction ◽  
Advantages And Disadvantages ◽  
Point Of Care Diagnostics ◽  
Working Principle

Nucleic acid extraction (NAE) plays a vital role in molecular biology as the primary step for many downstream applications. Many modifications have been introduced to the original 1869 method. Modern processes are categorized into chemical or mechanical, each with peculiarities that influence their use, especially in point-of-care diagnostics (POC-Dx). POC-Dx is a new approach aiming to replace sophisticated analytical machinery with microanalytical systems, able to be used near the patient, at thepoint of careorpoint of need. Although notable efforts have been made, a simple and effective extraction method is still a major challenge for widespread use of POC-Dx. In this review, we dissected the working principle of each of the most common NAE methods, overviewing their advantages and disadvantages, as well their potential for integration in POC-Dx systems. At present, it seems difficult, if not impossible, to establish a procedure which can be universally applied to POC-Dx. We also discuss the effects of the NAE chemicals upon the main plastic polymers used to mass produce POC-Dx systems. We end our review discussing the limitations and challenges that should guide the quest for an efficient extraction method that can be integrated in a POC-Dx system.

scholarly journals A Piezoelectric Flexural Plate Wave (FPW) Bio-MEMS Sensor with Improved Molecular Mass Detection for Point-of-Care Diagnostics

2019 ◽  
Vol 5 (1) ◽  
pp. 265-268 ◽  
Author(s):  
Christian Walk ◽  
Matthias Wiemann ◽  
Michael Görtz ◽  
Jens Weidenmüller ◽  
Andreas Jupe ◽  
...  
Keyword(s):  
Acoustic Waves ◽  
Point Of Care ◽  
Mass Loading ◽  
Mass Detection ◽  
Viscous Liquids ◽  
Mems Sensor ◽  
Point Of Care Diagnostics ◽  
Propagating Waves ◽  
Working Principle ◽  
Flexural Plate Wave

AbstractA piezoelectric FPW-sensor has been developed for a point of care device in this work. The Bio- MEMS FPW-sensor consists of an electrode configuration termed as an interdigital transducer (IDT) placed on a membrane. An input IDT excites and an output IDT detects the propagating acoustic waves through a PZT layer. Design optimizations and fabrication improvements of the FPW-sensor led to significantly reduced attenuation of the wave signal and the damping of the propagating waves between the IDTs. The working principle of mass loading is shown using different low-viscous liquids. A densitydependent sensitivity of -0.39 MHz/g/cm³ was evaluated. After the membrane was functionalized, the Bio-MEMS FPW-sensor was used to measure a specific chemokine in complex solution. By design improvements, the resolution was significantly increased from 0.7 Hz/nM to 14 Hz/nM.

Development of a whole-cell biosensor for the determination of tyrosine in urine for point-of-care diagnostics

2019 ◽  
Vol 11 (10) ◽  
pp. 1400-1404 ◽  
Author(s):  
Chieh Lin ◽  
Qian-Xian Zhang ◽  
Yi-Chun Yeh
Keyword(s):  
Point Of Care ◽  
Whole Cell ◽  
Point Of Care Diagnostics ◽  
Whole Cell Biosensor ◽  
Cell Biosensor

Two tyrosine-responsive promoters are used to differentially control the production of RFP and GFP signals in response to tyrosine levels in a culture.

scholarly journals A versatile capillaric microfluidics viscometer platform for bar-graph type point-of-care diagnostics

2021 ◽  
Author(s):  
Robert Claude Meffan ◽  
Julian Menges ◽  
Fabian Dolamore ◽  
Daniel Mak ◽  
Conan Fee ◽  
...  
Keyword(s):  
Field Effect Transistors ◽  
Point Of Care ◽  
Relative Viscosity ◽  
Microfluidic Channel ◽  
Flow Paths ◽  
Capillary Action ◽  
Point Of Care Diagnostics ◽  
Graph Type ◽  
Poly Ethylene ◽  
And Performance

A novel capillary action microfluidic viscometer has been designed that can measure the relative viscosity of a sample compared to a control liquid. Using capillary action circuits, the viscosity of a sample is transformed into a microfluidic bar-graph format without the use of external instrumentation. The bars in this case are represented by the distance that a liquid has flown through a microfluidic channel, relative to another liquid in an identical channel. As the device does not require external instrumentation, its use is targeted at point-of-care (PoC) situations. This implementation is made practical through capillaric Field Effect Transistors, and the conditional flow paths they enable. In this paper, we report on the design, operation, and performance of a two-channel version viscometer device exclusively based on capillary action circuits. Using poly-ethylene glycol solutions as viscous samples, we demonstrate that the device can transduce the relative viscosity consistently to within 2%. Enabled by the flexibility of the capillary action circuits, we additionally present a modified device which can measure transparent liquids without the need to add colorants to the sample. The forms of the device presented in this work have applications in both medical care and scientific measurements—particularly for PoC measurements.

scholarly journals COVID-19 Point-of-Care Diagnostics: Present and Future

ACS Nano ◽  
2021 ◽  
Author(s):  
Enrique Valera ◽  
Aaron Jankelow ◽  
Jongwon Lim ◽  
Victoria Kindratenko ◽  
Anurup Ganguli ◽  
...  
Keyword(s):  
Point Of Care ◽  
Point Of Care Diagnostics

scholarly journals 145 Point of care lung ultrasound in patient triage: integration of ultrasound into a streaming pathway for COVID-19

2020 ◽  
Vol 37 (12) ◽  
pp. 839.1-839
Author(s):  
Dominic Craver ◽  
Aminah Ahmad ◽  
Anna Colclough
Keyword(s):  
Point Of Care ◽  
District General Hospital ◽  
Training Programme ◽  
Service Evaluation ◽  
University Hospital ◽  
Junior Doctors ◽  
Point Of Care Ultrasound ◽  
Face To Face ◽  
Point Of Care Diagnostics ◽  
Audit Data

Aims/Objectives/BackgroundRapid risk stratification of patients is vital for Emergency Department (ED) streaming during the COVID-19 pandemic. Ideally, patients should be split into red (suspected/confirmed COVID-19) and green (non COVID-19) zones in order to minimise the risk of patient-to-patient and patient-to-staff transmission. A robust yet rapid streaming system combining clinician impression with point-of-care diagnostics is therefore necessary.Point of care ultrasound (POCUS) findings in COVID-19 have been shown to correlate well with computed tomography (CT) findings, and it therefore has value as a front-door diagnostic tool. At University Hospital Lewisham (a district general hospital in south London), we recognised the value of early POCUS and its potential for use in patient streaming.Methods/DesignWe developed a training programme, ‘POCUS for COVID’ and subsequently integrated POCUS into streaming of our ED patients. The training involved Zoom lectures, a face to face practical, a 10 scan sign off process followed by a final triggered assessment. Patient outcomes were reviewed in conjunction with their scan reports.Results/ConclusionsCurrently, we have 21 ED junior doctors performing ultrasound scans independently, and all patients presenting to our department are scanned either in triage or in the ambulance. A combination of clinical judgement and scan findings are used to stream the patient to an appropriate area.Service evaluation with analysis of audit data has found our streaming to be 94% sensitive and 79% specific as an indicator of COVID 19. Further analysis is ongoing.Here we present both the structure of our training programme and our integrated streaming pathway along with preliminary analysis results.

scholarly journals Point of Care Diagnostics in the Age of COVID-19

Diagnostics ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 9
Author(s):  
Meysam Rezaei ◽  
Sajad Razavi Bazaz ◽  
Sareh Zhand ◽  
Nima Sayyadi ◽  
Dayong Jin ◽  
...  
Keyword(s):  
Point Of Care ◽  
Diagnostic Methods ◽  
Global Public Health ◽  
Current Standard ◽  
Healthcare Facilities ◽  
Major Threat ◽  
Point Of Care Diagnostics ◽  
Recent Outbreak ◽  
Control Virus ◽  
Biosafety Level

The recent outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated serious respiratory disease, coronavirus disease 2019 (COVID-19), poses a major threat to global public health. Owing to the lack of vaccine and effective treatments, many countries have been overwhelmed with an exponential spread of the virus and surge in the number of confirmed COVID-19 cases. Current standard diagnostic methods are inadequate for widespread testing as they suffer from prolonged turn-around times (>12 h) and mostly rely on high-biosafety-level laboratories and well-trained technicians. Point-of-care (POC) tests have the potential to vastly improve healthcare in several ways, ranging from enabling earlier detection and easier monitoring of disease to reaching remote populations. In recent years, the field of POC diagnostics has improved markedly with the advent of micro- and nanotechnologies. Due to the COVID-19 pandemic, POC technologies have been rapidly innovated to address key limitations faced in existing standard diagnostic methods. This review summarizes and compares the latest available POC immunoassay, nucleic acid-based and clustered regularly interspaced short palindromic repeats- (CRISPR)-mediated tests for SARS-CoV-2 detection that we anticipate aiding healthcare facilities to control virus infection and prevent subsequent spread.

scholarly journals Revisiting Electrochemical Biosensing in the 21st Century Society for Inflammatory Cytokines Involved in Autoimmune, Neurodegenerative, Cardiac, Viral and Cancer Diseases

Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 189
Author(s):  
Susana Campuzano ◽  
Paloma Yáñez-Sedeño ◽  
José Manuel Pingarrón
Keyword(s):  
Point Of Care ◽  
Low Cost ◽  
Accurate Determination ◽  
Test Time ◽  
Electrochemical Biosensing ◽  
Recent Developments ◽  
Inflammatory Processes ◽  
Human Skills ◽  
Cancer Diseases

The multifaceted key roles of cytokines in immunity and inflammatory processes have led to a high clinical interest for the determination of these biomolecules to be used as a tool in the diagnosis, prognosis, monitoring and treatment of several diseases of great current relevance (autoimmune, neurodegenerative, cardiac, viral and cancer diseases, hypercholesterolemia and diabetes). Therefore, the rapid and accurate determination of cytokine biomarkers in body fluids, cells and tissues has attracted considerable attention. However, many currently available techniques used for this purpose, although sensitive and selective, require expensive equipment and advanced human skills and do not meet the demands of today’s clinic in terms of test time, simplicity and point-of-care applicability. In the course of ongoing pursuit of new analytical methodologies, electrochemical biosensing is steadily gaining ground as a strategy suitable to develop simple, low-cost methods, with the ability for multiplexed and multiomics determinations in a short time and requiring a small amount of sample. This review article puts forward electrochemical biosensing methods reported in the last five years for the determination of cytokines, summarizes recent developments and trends through a comprehensive discussion of selected strategies, and highlights the challenges to solve in this field. Considering the key role demonstrated in the last years by different materials (with nano or micrometric size and with or without magnetic properties), in the design of analytical performance-enhanced electrochemical biosensing strategies, special attention is paid to the methods exploiting these approaches.

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