scholarly journals Modifying Wicking Speeds in Paper-Based Microfluidic Devices by Laser-Etching

Micromachines ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 773
Author(s):  
Brent Kalish ◽  
Mick Kyle Tan ◽  
Hideaki Tsutsui
Keyword(s):  
Flow Control ◽  
Point Of Care ◽  
Low Cost ◽  
Microfluidic Devices ◽  
Diagnostic Tools ◽  
Laser Etching ◽  
Simple Process ◽  
Channel Geometry ◽  
Fluid Delivery ◽  
Reaction Zones

Paper-based microfluidic devices are an attractive platform for developing low-cost, point-of-care diagnostic tools. As paper-based devices’ detection chemistries become more complex, more complicated devices are required, often entailing the sequential delivery of different liquids or reagents to reaction zones. Most research into flow control has been focused on introducing delays. However, delaying the flow can be problematic due to increased evaporation leading to sample loss. We report the use of a CO2 laser to uniformly etch the surface of the paper to modify wicking speeds in paper-based microfluidic devices. This technique can produce both wicking speed increases of up to 1.1× faster and decreases of up to 0.9× slower. Wicking speeds can be further enhanced by etching both sides of the paper, resulting in wicking 1.3× faster than unetched channels. Channels with lengthwise laser-etched grooves were also compared to uniformly etched channels, with the most heavily grooved channels wicking 1.9× faster than the fastest double-sided etched channels. Furthermore, sealing both sides of the channel in packing tape results in the most heavily etched channels, single-sided, double-sided, and grooved, wicking over 13× faster than unetched channels. By selectively etching individual channels, different combinations of sequential fluid delivery can be obtained without altering any channel geometry. Laser etching is a simple process that can be integrated into the patterning of the device and requires no additional materials or chemicals, enabling greater flow control for paper-based microfluidic devices.

scholarly journals Point-of-Care Testing-the Key in the Battle against SARS-CoV-2 Pandemic

Micromachines ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1464
Author(s):  
Florina Silvia Iliescu ◽  
Ana Maria Ionescu ◽  
Larisa Gogianu ◽  
Monica Simion ◽  
Violeta Dediu ◽  
...  
Keyword(s):  
Clinical Decision Making ◽  
Point Of Care ◽  
Low Cost ◽  
Diagnostic Testing ◽  
Clinical Decision ◽  
Rapid Screening ◽  
Diagnostic Tools ◽  
Point Of Care Testing ◽  
Qrt Pcr ◽  
User Friendly

The deleterious effects of the coronavirus disease 2019 (COVID-19) pandemic urged the development of diagnostic tools to manage the spread of disease. Currently, the “gold standard” involves the use of quantitative real-time polymerase chain reaction (qRT-PCR) for SARS-CoV-2 detection. Even though it is sensitive, specific and applicable for large batches of samples, qRT-PCR is labour-intensive, time-consuming, requires trained personnel and is not available in remote settings. This review summarizes and compares the available strategies for COVID-19: serological testing, Point-of-Care Testing, nanotechnology-based approaches and biosensors. Last but not least, we address the advantages and limitations of these methods as well as perspectives in COVID-19 diagnostics. The effort is constantly focused on understanding the quickly changing landscape of available diagnostic testing of COVID-19 at the clinical levels and introducing reliable and rapid screening point of care testing. The last approach is key to aid the clinical decision-making process for infection control, enhancing an appropriate treatment strategy and prompt isolation of asymptomatic/mild cases. As a viable alternative, Point-of-Care Testing (POCT) is typically low-cost and user-friendly, hence harbouring tremendous potential for rapid COVID-19 diagnosis.

Smart Nanodevices for Point-of-Care Applications

2021 ◽  
Vol 17 ◽  
Author(s):  
Rajasekhar Chokkareddy ◽  
Suvardhan Kanchi ◽  
Inamuddin
Keyword(s):  
Chronic Diseases ◽  
Patient Monitoring ◽  
State Of The Art ◽  
Point Of Care ◽  
Low Cost ◽  
Medical Diagnostics ◽  
Diagnostic Tools ◽  
Current State ◽  
Rural Patients ◽  
Diagnosis Of Diseases

Background: While significant strides have been made to avoid mortality during the treatment of chronic diseases, it is still one of the biggest health-care challenges that have a profound effect on humanity. The development of specific, sensitive, accurate, quick, low-cost, and easy-to-use diagnostic tools is therefore still in urgent demand. Nanodiagnostics is defined as the application of nanotechnology to medical diagnostics that can offer many unique opportunities for more successful and efficient diagnosis and treatment for infectious diseases. Methods: In this review we provide an overview of infectious disease using nanodiagnostics platforms based on nanoparticles, nanodevices for point-of-care (POC) applications. Results: Current state-of-the-art and most promising nanodiagnostics POC technologies, including miniaturized diagnostic tools, nanorobotics and drug delivery systems have been fully examined for the diagnosis of diseases. It also addresses the drawbacks, problems and potential developments of nanodiagnostics in POC applications for chronic diseases. Conclusions: While progress is gaining momentum in this field and many researchers have dedicated their time in developing new smart nanodevices for POC applications for various chronic diseases, the ultimate aim of achieving longterm, reliable and continuous patient monitoring has not yet been achieved. Moreover, the applicability of the manufactured nanodevices to rural patients for on-site diagnosis, cost, and usability are the crucial aspects that require more research, improvements, and potential testing stations. Therefore, more research is needed to develop the demonstrated smart nanodevices and upgrade their applicability to hospitals away from the laboratories.

scholarly journals Programmable Paper-Based Microfluidic Devices for Biomarker Detections

Micromachines ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 516 ◽  
Author(s):  
Veasna Soum ◽  
Sooyong Park ◽  
Albertus Ivan Brilian ◽  
Oh-Sun Kwon ◽  
Kwanwoo Shin
Keyword(s):  
Point Of Care ◽  
High Sensitivity ◽  
Microfluidic Devices ◽  
Portable Devices ◽  
Biomarker Detection ◽  
Fluid Delivery ◽  
Wide Range ◽  
Paper Based Microfluidics ◽  
Digital Microfluidic ◽  
Detection Of Biomarkers

Recent advanced paper-based microfluidic devices provide an alternative technology for the detection of biomarkers by using affordable and portable devices for point-of-care testing (POCT). Programmable paper-based microfluidic devices enable a wide range of biomarker detection with high sensitivity and automation for single- and multi-step assays because they provide better control for manipulating fluid samples. In this review, we examine the advances in programmable microfluidics, i.e., paper-based continuous-flow microfluidic (p-CMF) devices and paper-based digital microfluidic (p-DMF) devices, for biomarker detection. First, we discuss the methods used to fabricate these two types of paper-based microfluidic devices and the strategies for programming fluid delivery and for droplet manipulation. Next, we discuss the use of these programmable paper-based devices for the single- and multi-step detection of biomarkers. Finally, we present the current limitations of paper-based microfluidics for biomarker detection and the outlook for their development.

scholarly journals Negligible-cost microfluidic device fabrication using 3D-printed interconnecting channel scaffolds

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0245206
Author(s):  
Harry Felton ◽  
Robert Hughes ◽  
Andrea Diaz-Gaxiola
Keyword(s):  
Rapid Prototyping ◽  
Point Of Care ◽  
Low Cost ◽  
Microfluidic Channel ◽  
Microfluidic Devices ◽  
Device Fabrication ◽  
Appropriate Technology ◽  
Channel Cross Section ◽  
Microfluidic Systems ◽  
3D Printed

This paper reports a novel, negligible-cost and open-source process for the rapid prototyping of complex microfluidic devices in polydimethylsiloxane (PDMS) using 3D-printed interconnecting microchannel scaffolds. These single-extrusion scaffolds are designed with interconnecting ends and used to quickly configure complex microfluidic systems before being embedded in PDMS to produce an imprint of the microfluidic configuration. The scaffolds are printed using common Material Extrusion (MEX) 3D printers and the limits, cost & reliability of the process are evaluated. The limits of standard MEX 3D-printing with off-the-shelf printer modifications is shown to achieve a minimum channel cross-section of 100×100 μm. The paper also lays out a protocol for the rapid fabrication of low-cost microfluidic channel moulds from the thermoplastic 3D-printed scaffolds, allowing the manufacture of customisable microfluidic systems without specialist equipment. The morphology of the resulting PDMS microchannels fabricated with the method are characterised and, when applied directly to glass, without plasma surface treatment, are shown to efficiently operate within the typical working pressures of commercial microfluidic devices. The technique is further validated through the demonstration of 2 common microfluidic devices; a fluid-mixer demonstrating the effective interconnecting scaffold design, and a microsphere droplet generator. The minimal cost of manufacture means that a 5000-piece physical library of mix-and-match channel scaffolds (100 μm scale) can be printed for ~$0.50 and made available to researchers and educators who lack access to appropriate technology. This simple yet innovative approach dramatically lowers the threshold for research and education into microfluidics and will make possible the rapid prototyping of point-of-care lab-on-a-chip diagnostic technology that is truly affordable the world over.

scholarly journals Host-Modulation Therapy and Chair-Side Diagnostics in the Treatment of Peri-Implantitis

Biosensors ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 44 ◽  
Author(s):  
Timo Sorsa ◽  
Joseph Bacigalupo ◽  
Mauno Könönen ◽  
Pirjo Pärnänen ◽  
Ismo T. Räisänen
Keyword(s):  
Point Of Care ◽  
Low Cost ◽  
Diagnostic Tools ◽  
Low Grade ◽  
Active Matrix ◽  
Point Of Care Test ◽  
Increased Risk ◽  
Prevention And Treatment ◽  
Potential Benefits ◽  
Low Grade Inflammation

Previous studies report periodontitis and peri-implantitis being able to induce systemic low-grade inflammation, which is known to be associated with increased risk for some systemic medical disease such as cardiovascular disease. In this regard, recent studies have shown that host modulation therapy (HMT) together with traditional mechanical and surgical treatment not only cease the progression of periodontitis but also reduce the systemic collagenolytic biomarkers in both oral fluids and circulation. This suggests that the corresponding adjunctive HMT-medication could be effective in the prevention and treatment of dental peri-implantitis, as well. Furthermore, low-cost, safe, and practical oral fluid active matrix metalloproteinase-8 (aMMP-8) lateral-flow immunotests have been proposed as point-of-care/chair-side diagnostic tools to detect peri-implantitis and periodontitis, and to monitor their effective resolutions, while using various therapeutic strategies, including host modulation. This study reports the potential benefits of HMT-medication in the prevention and treatment of dental peri-implantitis among five patients (four of five were current/ex-smokers). In addition, the aMMP-8 point-of-care test diagnosed 20 peri-implantitis and 20 healthy controls correctly. In conclusion, this study and previous studies support the potential effectiveness of HMT-medication(s) and point-of-care/chair-side technologies in the treatment and diagnostics/monitoring of peri-implantitis. However, more studies are needed to further confirm this.

Alleviating the Neglected Tropical Diseases: Recent Developments in Diagnostics and Detection

2018 ◽  
Vol 18 (18) ◽  
pp. 1559-1574 ◽  
Author(s):  
Satakshi Hazra ◽  
Sanjukta Patra
Keyword(s):  
Pathogen Detection ◽  
Neglected Tropical Diseases ◽  
Point Of Care ◽  
Low Cost ◽  
Holistic Approach ◽  
Diagnostic Tools ◽  
Tropical Diseases ◽  
Antimicrobial Drug Resistance ◽  
Diagnostic Measures ◽  
Specificity And Sensitivity

Background: Neglected tropical diseases (NTDs) are communicable diseases caused by a group of bacteria, viruses, protozoa and helminths prevalent in more than 145 countries that affect the world’s poverty stricken populations. WHO enlists 18 NTDs amongst people living in endemic areas having inaccessibility to preventive measures. Steps to reduce the global disease burden of the NTDs need attention at multi-factorial levels. Control programmes, mass drug administrations, transmission checks, eradication surveillances and diagnoses are some of them. The foremost in this list is confirmatory diagnosis. A comprehensive summary of the innovative, high-impact, multiplexed, low-cost diagnostic tools developed in the last decade that helped to meet the needs of users can depict a holistic approach to further evaluate potential technologies and reagents currently in research. Major Advancements: A literature survey based on developing nano-biotechnological platforms to meet the diagnostic challenges in NTDs towards development of a useful point-of-care (POC) unit is reported. However, in order to pave the way for complete eradication more sensitive tools are required that are user-friendly and applicable for use in endemic and low-resource settings. There are various novel research progresses/advancements made for qualitative and quantitative measurement of infectious load in some diseases like dengue, Chagas disease and leishmaniasis; though further improvements on the specificity and sensitivity front are still awaited. Strategies to combat the problem of antimicrobial drug resistance in diagnosis of NTDs have also been put forward by various research groups and organizations. Moreover, the state-of-the-art “omics” approaches like metabolomics and metagenomics have also started to contribute constructively towards diagnosis and prevention of the NTDs. Conclusion: A concrete solution towards a single specimen based common biomarker detection platform for NTDs is lacking. Identifying robust biomarkers and implementing them on simple diagnostic tools to ease the process of pathogen detection can help us understand the obstacles in current diagnostic measures of the NTDs.

Research Progress of Paper-Based Microfluidic Devices

2013 ◽  
Vol 421 ◽  
pp. 334-336 ◽  
Author(s):  
Yong Qiang Cheng ◽  
Cui Lian Guo ◽  
Yang Li ◽  
Bin Zhao ◽  
Xiao Cui
Keyword(s):  
Environmental Monitoring ◽  
Plasma Etching ◽  
Biological Samples ◽  
Recent Progress ◽  
Point Of Care ◽  
Low Cost ◽  
Microfluidic Devices ◽  
Research Progress ◽  
Potential Applications

Paper-based microfluidic devices have recently received increasing attention as a potential platform for its low cost, portability and excellent compatibility with biological samples. A variety of fabrication technologies were employed, including simple photolithography, wax plotting, printing, inkjet etching, plasma etching and so on. Meanwhile, the potential applications of paper-based microfluidic devices in diagnostic, point-of-care (POC), and environmental monitoring were reported. We review the recent progress of fabrication technologies and the applications of paper-based microfluidic devices.

Transient Modelling of Pneumatic Valves in Centrifugal Microfluidic Devices

2016 ◽  
Author(s):  
Michael R. Moon ◽  
Lin Lin
Keyword(s):  
Surface Tension ◽  
Point Of Care ◽  
Low Cost ◽  
Microfluidic Devices ◽  
Novel Technologies ◽  
Fluid Handling ◽  
Pneumatic Valves ◽  
Microfluidic Valves ◽  
And Control ◽  
Micrometer Scale

Point of care medical instruments benefit from compact fluid handling systems in the microliter range. To handle fluid volumes this small, many novel technologies have been studied. Pneumatic valves offer advantages over other microfluidic valves, including robustness and low cost. These valves are used in centrifugal microfluidic devices, a very active area of research, and take advantage of pneumatic and centrifugal pressure to aliquot and control the flow of fluid. The physics of fluids at the micrometer scale are complex and modelling their behavior using CFD software is challenging. Representing adhesion, surface tension, and other multiphase interactions is critical to accurately model microfluidic behavior. Centrifugal devices must also consider Coriolis, centrifugal, and Euler effects. In this study, a pneumatic valve was designed and simulated using commercial CFD software. The device was also fabricated for verification of the simulation. The simulation demonstrated the multiphase interactions of fluid and air within the rotating device. In a transient analysis of the model, a 6 μl volume of water is held in stable equilibrium by a compressed volume of air at low RPM, while at a higher RPM, the fluid is observed to displace the compressed air as a result of Rayleigh-Taylor instability. Actual devices with comparable geometry were built and tested. The behavior of the valve predicted in the model was in agreement with experimental results produced from the actual devices. The results of the simulation captured the stabilizing effect of both pneumatic pressure and surface tension at low RPM, as well as the instability that results from increased centrifugal and Euler pressure at higher RPM.

scholarly journals 3D-Printed Immunosensor Arrays for Cancer Diagnostics

Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4514 ◽  
Author(s):  
Mohamed Sharafeldin ◽  
Karteek Kadimisetty ◽  
Ketki S. Bhalerao ◽  
Tianqi Chen ◽  
James F. Rusling
Keyword(s):  
3D Printing ◽  
Early Stage ◽  
Point Of Care ◽  
Low Cost ◽  
Cancer Diagnostics ◽  
Diagnostic Tools ◽  
Protein Biomarkers ◽  
Protein Biomarker ◽  
Subtractive Manufacturing ◽  
3D Printed

Detecting cancer at an early stage of disease progression promises better treatment outcomes and longer lifespans for cancer survivors. Research has been directed towards the development of accessible and highly sensitive cancer diagnostic tools, many of which rely on protein biomarkers and biomarker panels which are overexpressed in body fluids and associated with different types of cancer. Protein biomarker detection for point-of-care (POC) use requires the development of sensitive, noninvasive liquid biopsy cancer diagnostics that overcome the limitations and low sensitivities associated with current dependence upon imaging and invasive biopsies. Among many endeavors to produce user-friendly, semi-automated, and sensitive protein biomarker sensors, 3D printing is rapidly becoming an important contemporary tool for achieving these goals. Supported by the widely available selection of affordable desktop 3D printers and diverse printing options, 3D printing is becoming a standard tool for developing low-cost immunosensors that can also be used to make final commercial products. In the last few years, 3D printing platforms have been used to produce complex sensor devices with high resolution, tailored towards researchers’ and clinicians’ needs and limited only by their imagination. Unlike traditional subtractive manufacturing, 3D printing, also known as additive manufacturing, has drastically reduced the time of sensor and sensor array development while offering excellent sensitivity at a fraction of the cost of conventional technologies such as photolithography. In this review, we offer a comprehensive description of 3D printing techniques commonly used to develop immunosensors, arrays, and microfluidic arrays. In addition, recent applications utilizing 3D printing in immunosensors integrated with different signal transduction strategies are described. These applications include electrochemical, chemiluminescent (CL), and electrochemiluminescent (ECL) 3D-printed immunosensors. Finally, we discuss current challenges and limitations associated with available 3D printing technology and future directions of this field.

scholarly journals Rapid and accurate detection of novel coronavirus SARS-CoV-2 using CRISPR-Cas3

2020 ◽  
Author(s):  
Kazuto Yoshimi ◽  
Kohei Takeshita ◽  
Seiya Yamayoshi ◽  
Satomi Shibumura ◽  
Yuko Yamauchi ◽  
...  
Keyword(s):  
Dna Cleavage ◽  
Detection Method ◽  
Point Of Care ◽  
Low Cost ◽  
Diagnostic Tools ◽  
Type I ◽  
Point Of Care Testing ◽  
Virus Surveillance ◽  
Single Base Pair ◽  
Novel Coronavirus

Novel coronavirus SARS-CoV-2 outbreaks have rapidly spread to multiple countries, highlighting the urgent necessity for fast, sensitive, and specific diagnostic tools for virus surveillance. Here, the previously unknown collateral single-stranded DNA cleavage we observed with type I CRISPR-Cas3 highlights its potential for development as a Cas3-mediated rapid (within 40 min), low-cost, instrument-free detection method for SARS-CoV-2. This Cas3-based assay is comparable with Cas12- and real-time reverse-transcriptase PCR-based assays in its speed and sensitivity, but offers greater specificity for single-base-pair discrimination while negating the need for highly trained operators. These findings support the use of CRISPR diagnostics for point-of-care testing in patients with suspected SARS-CoV-2 infections.

Sign in / Sign up

Export Citation Format

Share Document