scholarly journals A fully battery-powered inexpensive spectrophotometric system for high-sensitivity point-of-care analysis on a microfluidic chip

The Analyst ◽  
2016 ◽  
Vol 141 (12) ◽  
pp. 3898-3903 ◽  
Author(s):  
Maowei Dou ◽  
Juan Lopez ◽  
Misael Rios ◽  
Oscar Garcia ◽  
Chuan Xiao ◽  
...  
Keyword(s):  
Microfluidic Chip ◽  
Point Of Care ◽  
Low Cost ◽  
High Sensitivity ◽  
Power Supplies ◽  
Low Resource Settings ◽  
Low Resource ◽  
External Power

A low-cost b̲a̲ttery-powered s̲pectrophotometric s̲ystem (BASS) was developed for high-sensitivity point-of-care analysis in low-resource settings on a microfluidic chip without relying on external power supplies.

Towards biomarker-based tests that can facilitate decisions about prevention and management of preeclampsia in low-resource settings

2016 ◽  
Vol 54 (1) ◽  
Author(s):  
Nathalie Acestor ◽  
Jane Goett ◽  
Arthur Lee ◽  
Tara M. Herrick ◽  
Susheela M. Engelbrecht ◽  
...  
Keyword(s):  
Health Care Providers ◽  
Clinical Performance ◽  
Point Of Care ◽  
Low Cost ◽  
Care Providers ◽  
Low Resource Settings ◽  
Low Resource ◽  
High Resource ◽  
Rapid Assays ◽  
Urine Biomarkers

AbstractIn recent years, an increasing amount of literature is emerging on candidate urine and blood-based biomarkers associated with incidence and severity of preeclampsia (PE) in pregnant women. While enthusiasm on the usefulness of several of these markers in predicting PE is evolving, essentially all work so far has focused on the needs of high-resource settings and high-income countries, resulting primarily in multi-parameter laboratory assays based on proteomic and metabolomics analysis techniques. These highly complex methods, however, require laboratory capabilities that are rarely available or affordable in low-resource settings (LRS). The importance of quantifying maternal and perinatal risks and identifying which pregnancies can be safely prolonged is also much greater in LRS, where intensive care facilities that can rapidly respond to PE-related health threats for women and infants are limited. For these reasons, simple, low cost, sensitive, and specific point-of-care (POC) tests are needed that can be performed by antenatal health care providers in LRS and that can facilitate decisions about detection and management of PE. Our study aims to provide a comprehensive systematic review of current and emerging blood and urine biomarkers for PE, not only on the basis of their clinical performance, but also of their suitability to be used in LRS-compatible test formats, such as lateral flow and other variants of POC rapid assays.

scholarly journals A low-cost fluorescence reader for in vitro transcription and nucleic acid detection with Cas13a

2019 ◽  
Author(s):  
Florian Katzmeier ◽  
Lukas Aufinger ◽  
Aurore Dupin ◽  
Jorge Quinteiro ◽  
Matthias Lenz ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Limit Of Detection ◽  
Point Of Care ◽  
Low Cost ◽  
Nucleic Acid Detection ◽  
Fluorescence Detector ◽  
Flat Detector ◽  
Low Resource Settings ◽  
Low Resource

AbstractPoint-of-care testing (POCT) in low-resource settings requires tools that can operate independent of typical laboratory infrastructure. Due to its favorable signal-to-background ratio, a wide variety of biomedical tests utilize fluorescence as a readout. However, fluorescence techniques often require expensive or complex instrumentation and can be difficult to adapt for POCT. To address this issue, we developed a pocket-sized fluorescence detector costing less than $15 that is easy to manufacture and can operate in low-resource settings. It is built from standard electronic components, including an LED and a light dependent resistor, filter foils and 3D printed parts, and reliably detected less than 10 nM fluorescein concentrations (with a lower limit of detection of ≈6.8 nM), which is sufficient to follow typical biochemical reactions used in POCT applications. All assays are conducted on filter paper, which allows for a flat detector architecture to improve signal collection. We validate the device by quantifying in vitro RNA transcription and also demonstrate sequence-specific detection of target RNAs in the nanomolar range using a Cas13a-based fluorescence assay. Cas13a is a RNA-guided, RNA-targeting CRISPR effector with promiscuous RNase activity upon recognition of its RNA target. Cas13a sensing is highly specific and adaptable and in combination with our detector represents a promising approach for nucleic acid POCT. Furthermore, our open-source device architecture could be a valuable educational tool that integrates hardware, software and biochemistry concepts.

scholarly journals Point-of-care device to diagnose and monitor neonatal jaundice in low-resource settings

2017 ◽  
Vol 114 (51) ◽  
pp. E10965-E10971 ◽  
Author(s):  
Pelham A. Keahey ◽  
Mathieu L. Simeral ◽  
Kristofer J. Schroder ◽  
Meaghan M. Bond ◽  
Prince J. Mtenthaonnga ◽  
...  
Keyword(s):  
Total Bilirubin ◽  
Point Of Care ◽  
Low Cost ◽  
Neurological Impairment ◽  
Reference Laboratory ◽  
Reference Standard ◽  
Low Resource Settings ◽  
Low Resource ◽  
Increased Risk ◽  
Pilot Clinical Study

Newborns are at increased risk of jaundice, a condition in which excess bilirubin accumulates in blood. Left untreated, jaundice can lead to neurological impairment and death. Jaundice resulting from unconjugated hyperbilirubinemia is easily treated with exposure to blue light, and phototherapy systems have been developed for low-resource settings; however, there are no appropriate solutions to diagnose and monitor jaundice in these settings. To address this need we present BiliSpec, a low-cost reader and disposable lateral flow card designed to measure the concentration of total bilirubin from several drops of blood at the point of care. We evaluated the performance of BiliSpec, using blood from normal volunteers spiked with varying amounts of bilirubin; results measured using BiliSpec correlated well with a reference laboratory bilirubinometer (r = 0.996). We then performed a pilot clinical study using BiliSpec to measure total bilirubin in neonates at risk for jaundice at Queen Elizabeth Central Hospital in Blantyre, Malawi. Concentrations measured using BiliSpec correlated well with those measured using a laboratory reference standard in 94 patient samples ranging from 1.1 mg/dL to 23.0 mg/dL in concentration (r = 0.973). The mean difference between bilirubin levels measured with BiliSpec and the reference standard was 0.3 mg/dL (95% CI: −1.7–2.2 mg/dL).

scholarly journals Integrating high-performing electrochemical transducers in lateral flow assay

2021 ◽  
Author(s):  
Antonia Perju ◽  
Nongnoot Wongkaew
Keyword(s):  
High Performance ◽  
Point Of Care ◽  
Low Cost ◽  
High Sensitivity ◽  
Lateral Flow ◽  
Analytical Performance ◽  
Label Free ◽  
High Performing ◽  
Lateral Flow Assays ◽  
Electrochemical Transducers

AbstractLateral flow assays (LFAs) are the best-performing and best-known point-of-care tests worldwide. Over the last decade, they have experienced an increasing interest by researchers towards improving their analytical performance while maintaining their robust assay platform. Commercially, visual and optical detection strategies dominate, but it is especially the research on integrating electrochemical (EC) approaches that may have a chance to significantly improve an LFA’s performance that is needed in order to detect analytes reliably at lower concentrations than currently possible. In fact, EC-LFAs offer advantages in terms of quantitative determination, low-cost, high sensitivity, and even simple, label-free strategies. Here, the various configurations of EC-LFAs published are summarized and critically evaluated. In short, most of them rely on applying conventional transducers, e.g., screen-printed electrode, to ensure reliability of the assay, and additional advances are afforded by the beneficial features of nanomaterials. It is predicted that these will be further implemented in EC-LFAs as high-performance transducers. Considering the low cost of point-of-care devices, it becomes even more important to also identify strategies that efficiently integrate nanomaterials into EC-LFAs in a high-throughput manner while maintaining their favorable analytical performance.

scholarly journals Electroanalytical Biosensors for Circulating Tumor DNA Detection—A Brief Review

2021 ◽  
Author(s):  
Zhijia Peng ◽  
Xiaogang Lin ◽  
Weiqi Nian ◽  
Xiaodong Zheng ◽  
Jayne Wu
Keyword(s):  
Real Time ◽  
Point Of Care ◽  
Low Cost ◽  
High Sensitivity ◽  
High Specificity ◽  
Circulating Tumor Dna ◽  
Minimal Invasive ◽  
Diagnosis And Treatment ◽  
Detection Technology ◽  
Tumor Dna

Early diagnosis and treatment have always been highly desired in the fight against cancer, and detection of circulating tumor DNA (ctDNA) has recently been touted as highly promising for early cancer screening. Consequently, the detection of ctDNA in liquid biopsy gains much attention in the field of tumor diagnosis and treatment, which has also attracted research interest from the industry. However, traditional gene detection technology is difficult to achieve low cost, real-time and portable measurement of ctDNA. Electroanalytical biosensors have many unique advantages such as high sensitivity, high specificity, low cost and good portability. Therefore, this review aims to discuss the latest development of biosensors for minimal-invasive, rapid, and real-time ctDNA detection. Various ctDNA sensors are reviewed with respect to their choices of receptor probes, detection strategies and figures of merit. Aiming at the portable, real-time and non-destructive characteristics of biosensors, we analyze their development in the Internet of Things, point-of-care testing, big data and big health.

scholarly journals Applying heat and humidity using stove boiled water for decontamination of N95 respirators in low resource settings

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0255338
Author(s):  
Siddharth Doshi ◽  
Samhita P. Banavar ◽  
Eliott Flaum ◽  
Surendra Kulkarni ◽  
Ulhas Vaidya ◽  
...  
Keyword(s):  
Large Scale ◽  
Low Cost ◽  
Low Resource Settings ◽  
Low Resource ◽  
Surgical Masks ◽  
Temperature And Humidity ◽  
Similar Temperature ◽  
N95 Respirators ◽  
Electricity Access ◽  
Uv C

Global shortages of N95 respirators have led to an urgent need of N95 decontamination and reuse methods that are scientifically validated and available world-wide. Although several large scale decontamination methods have been proposed (hydrogen peroxide vapor, UV-C); many of them are not applicable in remote and low-resource settings. Heat with humidity has been demonstrated as a promising decontamination approach, but care must be taken when implementing this method at a grassroots level. Here we present a simple, scalable method to provide controlled humidity and temperature for individual N95 respirators which is easily applicable in low-resource settings. N95 respirators were subjected to moist heat (>50% relative humidity, 65–80°C temperature) for over 30 minutes by placing them in a sealed container immersed in water that had been brought to a rolling boil and removed from heat, and then allowing the containers to sit for over 45 minutes. Filtration efficiency of 0.3–4.99 μm incense particles remained above 97% after 5 treatment cycles across all particle size sub-ranges. This method was then repeated at a higher ambient temperature and humidity in Mumbai, using standard utensils commonly found in South Asia. Similar temperature and humidity profiles were achieved with no degradation in filtration efficiencies after 6 cycles. Higher temperatures (>70°C) and longer treatment times (>40 minutes) were obtained by insulating the outer vessel. We also showed that the same method can be applied for the decontamination of surgical masks. This simple yet reliable method can be performed even without electricity access using any heat source to boil water, from open-flame stoves to solar heating, and provides a low-cost route for N95 decontamination globally applicable in resource-constrained settings.

scholarly journals Low-Cost, Accessible Fabrication Methods for Microfluidics Research in Low-Resource Settings

Micromachines ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 461 ◽  
Author(s):  
Hoang-Tuan Nguyen ◽  
Ha Thach ◽  
Emmanuel Roy ◽  
Khon Huynh ◽  
Cecile Perrault
Keyword(s):  
Developing Countries ◽  
Scientific Community ◽  
Low Cost ◽  
Microfluidic Devices ◽  
Research Community ◽  
Access To Healthcare ◽  
Healthcare Industry ◽  
Low Resource Settings ◽  
Limited Access ◽  
Low Resource

Microfluidics are expected to revolutionize the healthcare industry especially in developing countries since it would bring portable, easy-to-use, self-contained diagnostic devices to places with limited access to healthcare. To date, however, microfluidics has not yet been able to live up to these expectations. One non-negligible factor can be attributed to inaccessible prototyping methods for researchers in low-resource settings who are unable to afford expensive equipment and/or obtain critical reagents and, therefore, unable to engage and contribute to microfluidics research. In this paper, we present methods to create microfluidic devices that reduce initial costs from hundreds of thousands of dollars to about $6000 by using readily accessible consumables and inexpensive equipment. By including the scientific community most embedded and aware of the requirements of healthcare in developing countries, microfluidics will be able to increase its reach in the research community and be better informed to provide relevant solutions to global healthcare challenges.

A Low-Resource Oxygen Blender Prototype for Use in Modified Bubble CPAP Circuits

2020 ◽  
Vol 14 (1) ◽  
Author(s):  
Jared Floersch ◽  
Elsa Hauschildt ◽  
Adam Keester ◽  
Samuel Poganski ◽  
Kiet Tran ◽  
...  
Keyword(s):  
Continuous Positive Airway Pressure ◽  
Airway Pressure ◽  
Positive Airway Pressure ◽  
Low Cost ◽  
World Health ◽  
Pure Oxygen ◽  
Hypodermic Needle ◽  
Low Resource Settings ◽  
Low Resource ◽  
Tract Infections

Abstract Continuous positive airway pressure (CPAP) is a method of respiratory support used around the world to treat children with lower respiratory tract infections (LRTI) (WHO, 2016, Oxygen Therapy for Children, World Health Organization, Geneva, Switzerland, Report). Bubble continuous positive airway pressure (bCPAP) is an effective form of CPAP that is currently used in both high- and low-resource countries. Low-cost, modified bCPAP devices have been designed as an ideal form of CPAP in low-resource areas (Bjorklund, A. R., Mpora, B. O., Steiner, M. E., Fischer, G., Davey, C. S., and Slusher, T. M., 2018, “Use of a Modified Bubble Continuous Positive Airway Pressure (bCPAP) Device for Children in Respiratory Distress in Low- and Middle-Income Countries: A Safety Study,” Paediatr. Int. Child Health, 39(3), pp. 1–8). However, patients in low-resource settings undergoing bCPAP treatment are often given pure oxygen, which has been linked to retinopathy of prematurity, cardiovascular complications, and patient mortality (Rodgers, J. L., Iyer, D., Rodgers, L. E., Vanthenapalli, S., and Panguluri, S. K., 2019, “Impact of Hyperoxia on Cardiac Pathophysiology,” J. Cell. Physiol., 234(8), pp. 1–9; Ramgopal, S., Dezfulian, C., Hickey, R. W., Au, A. K., Venkataraman, S., Clark, R. S. B., and Horvat, C. M., 2019, “Association of Severe Hyperoxemia Events and Mortality Among Patients Admitted to a Pediatric Intensive Care Unit,” JAMA Network Open, 2(8), p. e199812). This problem is typically avoided by using commercial oxygen blenders, which can titrate down the concentration of oxygen delivered to the minimum needed; however, these blenders can cost nearly 1000 USD and are almost always unavailable in low-resource settings. The lack of available low-cost oxygen blenders compatible with modified bCPAP circuits creates a barrier for low-resource hospitals to be able to provide blended oxygen to patients. There is a need for a low-cost oxygen blender for use in low-resource settings. We propose a passive oxygen blender that operates via entrainment of atmospheric air. The device can easily be assembled in low-resource areas using a 22 gauge hypodermic needle, two 3 cc syringes, tape or super glue, and the materials required for bCPAP—for approximately 1.40 USD per device. The blender has not been clinically tested yet, but can achieve oxygen concentrations as low as 60% with bCPAP levels of 5 cm H2O (490 Pa) when used in a standard bCPAP circuit without a patient.

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