Point of Care Diagnostics

Objective: This study was done to assess the accuracy of Accutrend GCT meter in determining blood cholesterol levels in our setup, with an aim to recommend its use in clinical practice
Methods: This cross sectional study was conducted on 251 healthy volunteers from April to May 2013. Capillary whole blood samples were obtained using sterile lancets and cholesterol levels were measured using Accutrend GCT meter (Roche Diagnostics, Mannheim, Germany) using the standard technique. Three ml whole blood was also collected in plain tubes by the same operator without applying a tourniquet. Serum cholesterol levels were determined using Merck Microlab 300 Automated Clinical Chemistry Analyser the same day. The laboratory technician performing this test was blinded to results obtained with Accutrend GCT meter. The seven patients with readings beyond the analytic range of the Accutrend GCT meter were excluded, meaning that data analysis was performed on 244 results only.
Results: Results of 182 males and 62 females having a mean age of 38.54± 15.25 years were analysed. There was a significant difference in mean cholesterol levels measured by Accutrend GCT and Microlab-300 (4.73± 0.74mmol/l and 4.67± 0.86 mmol/l; p=0.021), producing a measurement bias of 1.43% with Accutrend GCT meter. A strong positive correlation was found between the results of the two techniques (r=0.852 ,p<0.001).
Conclusions: Accutrend GCT meter provides accurate measurement of blood cholesterol levels and its use should be encouraged for point-of-care measurements.

While developing an effective vaccine can take months up to years, detection of infected patients seems like one of the best ideas for controlling the situation. The role of biosensors in containing highly pathogenic viruses, saving lives and economy is evident. A new competitive numerical platform specifically for designing microfluidic-integrated biosensors is developed and presented in this work. Properties of the biosensor, sample, buffer fluid and even the microfluidic channel can be modified in this model. This feature provides the scientific community with the ability to design a specific biosensor for requested point-of-care (POC) applications. First, the validation of the presented numerical platform against experimental data and then results and discussion, highlighting the important role of the design parameters on the performance of the biosensor is presented. For the latter, the baseline case has been set on the previous studies on the biosensors suitable for SARS-CoV, ...

The field of centrifugal microfluidics has experienced tremendous growth during the past 15 years, especially in applications such as lab-on-a-disc (LoD) diagnostics. The strength of LoD systems lies in its potential for development into fully integrated sample-to-answer analysis systems. This review highlights the technologies necessary to develop the next generation of these systems. In addition to outlining valving and other fluid-handling operations, we discuss the recent advances and future outlook in four categories of LoD processes: reagent storage, sample preparation, nucleic acid amplification, and analyte detection strategies.

Bringing a diagnostic point of care test (POCT) to a healthcare market can be a painful experience as it requires the manufacturer to meet considerable technical, financial, managerial, and regulatory challenges. In this opinion article we propose a framework for developing the evidence needed to support product development, marketing, and adoption. We discuss each step in the evidence development pathway from the invention phase to the implementation of a new POCT in the healthcare system. We highlight the importance of articulating the value propositions and documenting the care pathway. We provide guidance on how to conduct care pathway analysis as little has been published on this. We summarize the clinical, economic and qualitative studies to be considered for developing evidence, and provide useful links to relevant software, on-line applications, websites, and give practical advice. We also provide advice on patient and public involvement and engagement (PPIE), and on product...

We assessed xurography and laser ablation for the manufacture of passive micromixers arrays to explore the scalability of unconventional manufacture technologies that could be implemented under the restrictions of the Point of Care for developing countries. In this work, we present a novel split-and-recombine (SAR) array design adapted for interfacing standardized dispensing (handheld micropipette) and sampling (microplate reader) equipment. The design was patterned and sealed from A4 sized vinyl sheets (polyvinyl chloride), employing low-cost disposable materials. Manufacture was evaluated measuring the dimensional error with stereoscopic and confocal microscopy. The micromixing efficiency was estimated using a machine vision system for passive driven infusion provided by micropippetting samples of dye and water. It was possible to employ rapid fabrication based on xurography to develop a four channel asymmetric split-and-recombine (ASAR) micromixer with mixing efficiencies ranging...

Despite the growth of research in universities on point-of-care (POC) diagnostics for global health, most devices never leave the laboratory. The processes that move diagnostic technology from the laboratory to the field-the processes intended to evaluate operation and performance under realistic conditions-are more complicated than they might seem. Two case studies illustrate this process: the development of a paper-based device to measure liver function, and the development of a device to identify sickle cell disease based on aqueous multiphase systems (AMPS) and differences in the densities of normal and sickled cells. Details of developing these devices provide strategies for forming partnerships, prototyping devices, designing studies, and evaluating POC diagnostics. Technical and procedural lessons drawn from these experiences may be useful to those designing diagnostic tests for developing countries, and more generally, technologies for use in resource-limited environments.

Recent infectious disease outbreaks, such as COVID-19 and Ebola, have highlighted the need for rapid and accurate diagnosis to initiate treatment and curb transmission. Successful diagnostic strategies critically depend on the efficiency of biological sampling and timely analysis. However, current diagnostic techniques are invasive/intrusive and present a severe bottleneck by requiring specialist equipment and trained personnel. Moreover, centralised test facilities are poorly accessible and the requirement to travel may increase disease transmission. Self-administrable, point-of-care (PoC) microneedle diagnostic devices could provide a viable solution to these problems. These miniature needle arrays can detect biomarkers in/from the skin in a minimally invasive manner to provide (near-) real-time diagnosis. Few microneedle devices have been developed specifically for infectious disease diagnosis, though similar technologies are well established in other fields and generally adaptable for infectious disease diagnosis. These include microneedles for biofluid extraction, microneedle sensors and analyte-capturing microneedles, or combinations thereof. Analyte sampling/detection from both blood and dermal interstitial fluid is possible. These technologies are in their early stages of development for infectious disease diagnostics, and there is a vast scope for further development. In this review, we discuss the utility and future outlook of these microneedle technologies in infectious disease diagnosis.

Oasis Diagnostics has developed two products to address the need for providing a saliva sample for use in final quantitative analysis of relevant biological analytes in a Point-of-Care (POC) or Point–of-Use (POU) environment. The first product is a real-time quantitative POC/POU Salivary Cortisol test (VerOFy®) that utilizes a fluorescent Lateral Flow Test (LFT) cassette in combination with a Saliva Collection/Purification device. The LFT cassette is then quantitated with a Litebox Image Analysis System (LIAM) which detects the fluorescent bands on the LTF strip. Image Analysis and data transfer is accomplished with an onboard processor, and bluetooth internet data transfer. Each cassette is recognized for test analyte, and lot specific information via QR codes and transferred to the processor on the LIAM. LIAM instrument controls are simple, easy to use, and results are visualized on the onboard screen. The cortisol assay can detect cortisol values in saliva within a standard range...

Point-of-care (POC) and disposable biomedical applications demand low-power microfluidic systems with pumping components that provide controlled pressure sources. Unfortunately, external pumps have hindered the implementation of such microfluidic systems due to limitations associated with portability and power requirements. Here, we propose and demonstrate a &#39;finger-powered&#39; integrated pumping system as a modular element to provide pressure head for a variety of advanced microfluidic applications, including finger-powered on-chip microdroplet generation. By utilizing a human finger for the actuation force, electrical power sources that are typically needed to generate pressure head were obviated. Passive fluidic diodes were designed and implemented to enable distinct fluids from multiple inlet ports to be pumped using a single actuation source. Both multilayer soft lithography and injection molding processes were investigated for device fabrication and performance. Experimen...

The overall goal of this research is to develop a new point-of-care system for early detection and characterization of cardiac markers to aid in diagnosis of acute coronary syndrome. The envisioned final technology platform incorporates functionalized gold colloidal nanoparticles trapped at the entrance to a nanofluidic device providing a robust means for analyte detection at trace levels using surface enhanced

In order to satisfy an emergent demand in point of care (POC) diagnostics as well as low resource settings such as in developing countries, we have integrated optical and bio-medical engineering to implement a device, which detects pathogens and displays test results using cell phones. The device employs DNA amplification and off-the-shelf components to obtain the diagnosis. Keywords-component; Bio Instrumentation,

New tools are needed to enable rapid detection, identification, and reporting of infectious viral and microbial pathogens in a wide variety of point-of-care applications that impact human and animal health. We report the design, construction, and characterization of a platform for multiplexed analysis of disease-specific DNA sequences that utilizes a smartphone camera as the sensor in conjunction with a handheld &quot;cradle&quot; that interfaces the phone with a silicon-based microfluidic chip embedded within a credit card-sized cartridge. Utilizing specific nucleic acid sequences for four equine respiratory pathogens as representative examples, we demonstrate the ability of the system to utilize a single 15 µL droplet of test sample to perform selective positive/negative determination of target sequences, including integrated experimental controls, in approximately 30 minutes. Our approach utilizes loop mediated isothermal amplification (LAMP) reagents pre-deposited into distinct ...

ABSTRACT Point Of Care (POC) Diagnostics from Bench to Market Ali Karami Research Centre of Molecular Biology, Baqiyatallah University of Medical Sciences. Karami@bmsu.ac.ir Point-of-care test (POC) also known as bedside, near-patient testing is defined as medical testing at or near the site of patient care.The current diagnostic laboratory system has been slow to change, and when properly evaluated is in need of change to a more patient-centered system (personalized medicine and companion diagnostics). The market for in vitro diagnostic (IVD) testing is estimated to be $54 billion in 2013, with POC, according to several market research company reports, representing 14% to 15% of the market. With the evolution of blood glucose, blood gas, urinalysis, pregnancy, and coagulation testing in the mid-1990s, the menu of POCs has expanded from fewer than 10 tests available in 1995 to approximately 110 tests available today. It is predicted that point of care testing market will be approximately US$ 25 Billion by 2016. Blood glucose test controls a lion’s market share of around 70% for the year 2011 and it is expected to continue its dominance till 2016. Infectious disease testing market is expected to double by 2016 from its market of 2011. As countries are making the healthcare more and more accessible to people, POC is found in several environments: hospital bedside, ambulatory care settings (clinics or physician offices), alternate care (skilled nursing facilities), and home settings. Benefits of POCT The key benefits of point-of-care include:

Microfluidic, cellular co-cultures that approximate macro scale biology are important tools for refining the in vitro study of organ level function and disease. In recent years, advances in technical fabrication and biological integration have provided new insights into biological phenomena, improved diagnostic measurements and made major steps toward de novo tissue creation. Here we review applications of these technologies specific to the cardiovascular field, emphasizing three general categories of use: reductionist vascular models, tissue-engineered vascular models and point-of-care diagnostics. With continued progress in the ability to purposefully control microscale environments, the detailed study of both primary and cultured cells may find new relevance in the general cardiovascular research community.

Fungal diseases of plants are of great economic importance causing 70–80% of crop losses associated with microbial plant pathogens. Advanced on-site disease diagnostics is very important to maximize crop productivity. In this study, diagnostic systems have been developed for simultaneous detection and identification of six fungal pathogens using 48-well microarrays (micromatrices) for qPCR. All oligonucleotide sets were tested for their specificity using 59 strains of target and non-target species. Detection limit of the developed test systems varied from 0.6 to 43.5 pg of DNA depending on target species with reproducibility within 0.3−0.7% (standard deviation). Diagnostic efficiency of test systems with stabilized and freeze-dried PCR master-mixes did not significantly differ from that of freshly prepared microarrays, though detection limit increased. Validation of test systems on 30 field samples of potato plants showed perfect correspondence with the results of morphological iden...

Staphylococcus aureus is closely ass ociated with f ood poisoni ng inci dences, more, becaus e of i nt oxication due to
contamination of food with its enterotoxins. Staphylococcus enterotoxin A (SEA) i s highl y r es is tant to heat and
other f ood processing condi ti ons and has been i mplicated i n f ood bor ne diseases from dair y products. Here we
describe a r apid, gol d nanoparticl e bas ed lateral flow immunoassay (LFIA) for detecting SEA in milk. Assay is in
sandwich format and uses two specifi c monoclonal antibodies against SEA, one of which is labeled with gold
nanoparticles and other is immobilized at control line. We also demonstrate the effect of using a combination
of additives in captur e antibody in order t o enhance assay s ensitivity. The developed LFIA is specific and has a
lower detecti on limit of 0.5 μg/ml. LFIA is tested both on spiked buffer and milk samples and display good repro-ducibility. The assembled strips s tabl e f or a month at 4 ° C. The met hod may be suitable for t esting SEA i n milk
samples as i t i s qui ck, easy t o per form and r eproduci bl e

Background

The diagnosis of cystic echinococcosis (CE) is based primarily on imaging, in particular with ultrasound for abdominal CE, complemented by serology when imaging results are unclear. In rural endemic areas, where expertise in ultrasound may be scant and conventional serology techniques are unavailable due to lack of laboratory equipment, Rapid Diagnostic Tests (RDTs) are appealing.
Methodology/Principal Findings

We evaluated the diagnostic accuracy of 3 commercial RDTs for the diagnosis of hepatic CE. Sera from 59 patients with single hepatic CE cysts in well-defined ultrasound stages (gold standard) and 25 patients with non-parasitic cysts were analyzed by RDTs VIRapid HYDATIDOSIS (Vircell, Spain), Echinococcus DIGFA (Unibiotest, China), ADAMU-CE (ICST, Japan), and by RIDASCREEN Echinococcus IgG ELISA (R-Biopharm, Germany). Sensitivity, specificity and ROC curves were compared with McNemar and t-test. For VIRapid and DIGFA, correlation between semiquantitative results and ELISA OD values were evaluated by Spearman’s coefficient. Reproducibility was assessed on 16 randomly selected sera with Cohen’s Kappa coefficient. Sensitivity and Specificity of VIRapid (74%, 96%) and ADAMU-CE (57%, 100%) did not differ from ELISA (69%, 96%) while DIGFA (72%, 72%) did (p = 0.045). ADAMU-CE was significantly less sensitive in the diagnosis of active cysts (p = 0.019) while DIGFA was significantly less specific (p = 0.014) compared to ELISA. All tests were poorly sensitive in diagnosing inactive cysts (33.3% ELISA and ADAMU-CE, 42.8% DIGFA, 47.6% VIRapid). The reproducibility of all RDTs was good-very good. Band intensity of VIRapid and DIGFA correlated with ELISA OD values (r = 0.76 and r = 0.79 respectively, p<0.001).
Conclusions/Significance

RDTs may be useful in resource-poor settings to complement ultrasound diagnosis of CE in uncertain cases. VIRapid test appears to perform best among the examined kits, but all tests are poorly sensitive in the presence of inactive cysts, which may pose problems with accurate diagnosis.