Point-of-care Testing Devices Research Articles

Sample-to-answer point-of-care testing platform for quantitative detection of small molecules in blood using a smartphone-and microfluidic-based nanoplasmonic biosensor

Rapid and ultrasensitive detection of small molecules is of great significance in point-of-care testing (POCT) for health management and biomarker detection for many diseases. In this study, a novel POCT device integrated with a metasurface plasmon resonance (MetaSPR) chip with diffusion film enhancement was designed and controlled by a smartphone app for small molecule ultrasensitive detection based on competitive immunoassays. In this method, the sample competes with the antigen immobilized on the chip, and labeled antibodies are pumped from the sample pad to the chip for multiplexed and sample-to-answer analysis of blood. The entire process of detection is 14.3-fold less time (210 s in total) compared to an enzyme-linked immunosorbent assay (ELISA). For this assay, the limit of detection was 0.36 ppt and 1.05 ppt for testosterone and 25-hydroxyvitamin D3, respectively, and showed 100- to 1000-fold greater sensitivity than that of ELISA. Collectively, the data suggest that this novel POCT platform, based on a MetaSPR biosensor, provides ultrasensitive, rapid, regenerable, versatile, and real-time quantitative analysis for applications in health management and early diagnosis.

Tracking the Risk of Cardiovascular Disease after Almond and Oat Milk Intervene or Statin Medication with a Powerful Reflex SH-SAW POCT Platform.

Cardiovascular disease (CVD) represents the leading cause of death worldwide. For individuals at elevated risk for cardiovascular disease, early detection and monitoring of lipid status is imperative. The majority of lipid measurements conducted in hospital settings employ optical detection, which necessitates the use of relatively large-sized detection machines. It is, therefore, necessary to develop point-of-care testing (POCT) for lipoprotein in order to monitor CVD. To enhance the management and surveillance of CVD, this study sought to develop a POCT approach for apolipoprotein B (ApoB) utilizing a shear horizontal surface acoustic wave (SH-SAW) platform to assess the risk of heart disease. The platform employs a reflective SH-SAW sensor to reduce the sensor size and enhance the phase-shifted signals. In this study, the platform was utilized to monitor the impact of a weekly almond and oat milk or statins intervention on alterations in CVD risk. The SH-SAW ApoB test exhibited a linear range of 0 to 212 mg/dL, and a coefficient correlation (R) of 0.9912. Following a four-week intervention period, both the almond and oat milk intervention (-23.3%, p < 0.05) and statin treatment (-53.1%, p < 0.01) were observed to significantly reduce ApoB levels. These findings suggest that the SH-SAW POCT device may prove a valuable tool for monitoring CVD risk, particularly during routine daily or weekly follow-up visits.

A-338 Assessing the Technical and Analytical Performance of Point of Care Testing Devices for Blood Lipids Measurements

Abstract Background Cardiovascular diseases (CVDs) are the leading cause of death worldwide, causing over 17 million deaths each year. According to the World Health Organization (WHO), 85% of CVD deaths are due to heart disease and strokes, and over 75% occur in low- and middle-income countries (LMICs). Early detection and treatment are key to preventing consequences of CVD. Point-of-care testing (POCT) devices require minimal laboratory infrastructure and can be used to screen hard-to-reach populations for CVD risk. These devices are increasingly used in traditional care settings including hospitals and primary healthcare, and in non-traditional settings such as pharmacies. Although POCT devices offer fast and convenient testing, the analytical performance of these devices must produce accurate and reliable results, and have technical suitability for use. Several POCT devices for total cholesterol (TC) and other blood lipids are commercially available, however, the operational and analytical performance of these devices is not fully known. Methods Eight POCT devices for blood lipids were used in this study. For the technical assessment, a checklist was developed and applied, outlining the operational functionality and environmental conditions of the devices. Some relevant technical parameters in this checklist included requirements for temperature/humidity and power/voltage, storage conditions, and assay/test time. The analytical performance was assessed for parameters, such as accuracy and imprecision, using paired whole blood and serum donor samples for TC. In addition, these analytical parameters were assessed for serum High Density Lipoprotein-cholesterol (HDL-c) and Low Density Lipoprotein-cholesterol (LDL-c) samples on seven POCT devices. All samples were representative of a clinically relevant concentration range for TC, HDL-c, and LDL-c. Accuracy was compared to reference values obtained by the CDC reference measurement procedures. Results The mean bias for TC ranged among devices from -8.17% to 11.99% for whole blood and -7.89% to 7.02% for serum, respectively. The mean imprecision for TC in whole blood ranged from 1.94% to 11.63%, and in serum from 1.72% to 12.70%. The mean bias for serum HDL-c samples ranged from -7.33% to 17.36%, and for serum LDL-c samples from -20.92% to 5.04%. The mean imprecision for serum HDL-c samples ranged from 2.39% to 24.27% and for serum LDL-c samples ranged from 3.14% to 18.33%. For three of the eight devices, about 25% of the whole blood measurements and 50% of the serum measurements were reported outside of the measurement range and not included in the assessment. Comparing these non-reports with the reference values of these samples indicate that all of the reference values for whole blood and about 80% of the reference values for serum were actually within the measurement range of the device. Conclusions The technical assessment was helpful in building screening capacity in areas with limited laboratory infrastructure. The analytical assessment indicates notable differences in accuracy and precision for lipids measured in whole blood and serum, with serum measurements being more likely within performance requirements used by CDC's standardization programs. Additional studies to assess other devices and/or analytes, and future work to assist manufacturers improve the analytical performance of POCT devices are needed.

Impact of Point-of-Care Lactate Testing for Sepsis on Bundle Adherence and Clinical Outcomes in the Emergency Department: A Pre-Post Observational Study.

Background: The early diagnosis and prompt treatment of sepsis can enhance clinical outcomes. This study aimed to assess the relationship between point-of-care testing (POCT) for lactate levels and both adherence to the Surviving Sepsis Campaign (SSC) guidelines and mortality rates among sepsis patients in the emergency department (ED). We hypothesized that bedside lactate POCT would lead to better clinical outcomes. Methods: We conducted a pre-post observational study utilizing data from a prospectively collected sepsis registry. Following the introduction of lactate POCT, lactate levels were determined using both the central laboratory pathway and a POCT device. We then compared the characteristics and clinical outcomes between the periods before and after the introduction of POCT lactate measurement. Results: The analysis included a total of 1191 patients. The introduction of bedside lactate POCT led to a significant reduction in the time taken to obtain lactate results (from 53 to 33 min) and an increase in the rate of subsequent lactate measurements (from 82.1% to 88.2%). Lactate POCT did not significantly affect adherence to the overall SSC guidelines bundle (47.5% vs. 45.0%) or reduce 30-day mortality rates (31.1% vs. 31.4%). However, bedside lactate POCT could decrease extremely delayed lactate measurements. Conclusions: Bedside lactate POCT successfully reduced the time to obtain lactate results. Although lactate POCT did not lead to improved adherence to the overall SSC guidelines bundle or affect short-term mortality rates in sepsis patients, it may have an advantage in a specific situation such as overcrowded ED where there are subsequent or multiple measurements required.

Solid-Phase microextraction on Self-Driven microfluidic chip using capillary micropump and microvalves for saliva electrochemical analysis

The real-time detection of biomarkers in saliva is of great significance for early non-invasive diagnostic of related diseases. In this work, molecular imprinting technology was used to prepare a lactic acid monolithic column, which could realize specific adsorption and elution of lactic acid, achieving solid phase microextraction (SPME) of lactic acid in samples, and purify the analytes. Lactic acid monolithic column was then embedded into the microfluidic channel, and passive microfluidic structures such as stop valve, retention valve, trigger valve and capillary pump were utilized to construct the SPME self-driven microfluidic chip. A series of complex operations such as lactic acid adsorption, rinse and elution on the monolithic column could be realized automatically without external power. Since the purification of the analytes was achieved by the monolithic column, the low-cost nano copper oxide modified electrode was used to achieve the specific electrochemical analysis of lactic acid. The screen-printed electrode was designed and fabricated, and the integrated electrochemical detection circuit was used to realize the portable analysis of Na+, K+ and lactic acid simultaneously. The microfluidic chip, screen-printed electrode and miniaturized detection circuit are integrated into a Point-of-care testing (POCT) device, which realizes the automatically real-time detection of saliva. By adjusting the template molecule in monolithic column polymerization, the application of this physiological fluid POCT device can be extended, and may provide some implications for the development of portable non-invasive health monitoring devices.

Paper-Based procalcitonin and Interleukin-6 test strip with Spectrum-Based optical reader for enterovirus severity differentiation in children

Infectious diseases significantly impact global health, necessitating prompt diagnosis to mitigate life-threatening sepsis risk. Identifying patients at risk of severe neurological complications from enterovirus infections is challenging due to nonspecific initial presentations. Point-of-care testing (POCT) has emerged as a transformative tool, with low-cost lateral-flow colorimetric assays showing promise in deployable POCT devices. We developed a PCT/IL-6 rapid diagnostic system integrating lateral flow assay (LFA) test strips and a portable optical spectrum reader, allowing simultaneous semi-quantitative measurement of serum PCT and IL-6 within 30 min at the point of care. The system demonstrated a strong correlation with traditional ELISA and effectively differentiated severe pediatric enterovirus cases using serum samples. IL-6 showed superior discriminatory ability over PCT in identifying patients with severe neurological complications. This novel diagnostic platform holds great potential for early sepsis recognition and infectious disease management, especially in resource-limited settings.

Recent Developments in Personal Glucose Meters as Point-of-Care Testing Devices (2020-2024).

Point-of-care testing (POCT) is a contemporary diagnostic approach characterized by its user-friendly nature, cost efficiency, environmental compatibility, and lack of reliance on professional experts. Therefore, it is widely used in clinical diagnosis and other analytical testing fields to meet the demand for rapid and convenient testing. The application of POCT technology not only improves testing efficiency, but also brings convenience and benefits to the healthcare industry. The personal glucose meter (PGM) is a highly successful commercial POCT tool that has been widely used not only for glucose analysis, but also for non-glucose target detection. In this review, the recent advances from 2020 to 2024 in non-glucose target analysis for PGMs as POCT devices are summarized. The signal transduction strategies for non-glucose target analysis based on PGMs, including enzymatic transduction, nanocarrier transduction (enzyme or glucose), and glucose consumption transduction are briefly introduced. Meanwhile, the applications of PGMs in non-glucose target analysis are outlined, encompassing biomedical, environmental, and food analysis, along with other diverse applications. Finally, the prospects of and obstacles to employing PGMs as POCT tools for non-glucose target analysis are discussed.

Contamination-Free Reference Electrode Using Prussian Blue for Small Oxygen Sensors.

In recent years, significant attention has been directed toward advancing compact, point-of-care testing (POCT) devices to better deliver patient care and alleviate the burden on the medical care system. Common POCTs, such as blood oxygen sensors, leverage electrochemical sensing in their design. However, conventional electrochemical devices typically use Ag/AgCl reference electrodes, which are likely to release trace amounts of silver ions that contaminate the working electrode, causing rapid deterioration of the devices. This study proposes an effective reference electrode using graphene-coated porous silica spheres (G/PSS) with embedded Prussian blue (PB), denoted PB/G/PSS, designed specifically for small oxygen sensors. PB is a redox species that is an improvement over Ag/AgCl since it is significantly less water-soluble than AgCl. Since PB is an insulator, we dispersed PB in G/PSS, well-conductive mesoporous matrices, to ensure contact between PB clusters and the electrolytes. Moreover, the monodispersed, spherically shaped PB/G/PSS is an advantageous medium for fabricating POCT devices by screen printing. In this study, the open-circuit potential of the PB/G/PSS electrode remained stable within 30 mV for 31 days. The small oxygen sensor assembled through screen printing using PB/G/PSS demonstrated stable operation for several days or more. In contrast, a similar sensor with Ag/AgCl reference electrode rapidly deteriorated within a day. This PB/G/PSS reference electrode with improved stability is expected to be an excellent alternative to the Ag/AgCl system for small electrochemical-based POCT devices.

Gas Phase Aldehydes Detection in Exhaled Breath in Screening of Barrett's Esophagus

Aldehydes, e.g., acetaldehyde, have been classified as toxic and carcinogenic volatile organic compounds (VOCs) and are recognized as one determinant of upper aerodigestive tract cancer like Barrett's esophagus. Measuring aldehyde levels in breath provides information about the aldehydes released by abnormal cells, the level of aldehyde dehydrogenase (ALDH2) activity, and risks and diseases associated with high levels of acetaldehyde, which include liver disease and lung and upper digestive cancers. Devices currently available for breath analysis are state-of-the-art, high-resolution mass spectrometry instruments. These instruments have some drawbacks such as size, initial cost, and operational expense. Electrochemical sensors are capable of miniaturization and are available as portable and handheld breathalyzers. The non-invasive nature of breath analysis and its easy sampling makes smaller devices a more attractive alternative, particularly for continuous monitoring and point-of-care (POC) testing.1 However, the lack of an exchangeable/disposable sensing element, the resulting memory effect, and the need for frequent recalibration is the main drawback of currently available electrochemical breathalyzers.Herein we examine the feasibility of a POC testing device for aldehyde in exhaled breath to assess the medical application of such a device in noninvasive diagnostic testing for Barrett’s esophagus. To improve the selectivity of the method we harness the unique catalytic activity of the aminoxyl radical/oxoammonium redox couple toward aldehyde oxidation. The highly selective/sensitive device offers the capability for use in the detection of Barrett's esophagus, ideally at early stages, without the need for a high-cost screening test. Our functional sensing element consists of a screen-printed electrode (SPE) in which the graphene oxide-based is the working electrode. Exposing this electrode to simulated breath that contains aldehyde, while applying the required potential for oxidation of the aminoxyl radical (4-acetamido-TEMPO known as ACT), generates an electrocatalytic current proportional to the aldehyde concentration in the breath. These simple, sensitive, durable, and inexpensive electrodes may contribute to the development of a single-use reliable aldehyde sensor for personal or law enforcement applications.1. M. Mayer, M. Rafiee, Electrocatalytic Detection of Ethanol and Acetaldehyde by Aminoxyl Radicals: Utilizing Molecular Catalysis for Breath Analysis. Analyst 147, 2022, 3420 – 3423.

Exonuclease III/Cas12a Cascade Amplification Strategy and Smartphone-Based Portable Fluorescence Detector to Repurpose the Commercial AFP Strip for the POCT of Multiple RNAs.

Point of care testing (POCT) of nucleic acid (NA) contributes to the timely disease diagnosis, like bacteria and virus screening in households or resource-constrained areas, but its development has always been stagnant. Herein, we proposed an exonuclease III cascaded with CRISPR/Cas12a (Exo-III/Cas12a) amplification strategy and constructed a smartphone-based portable fluorescence detector (SPFD) to repurpose the commercial alpha-fetoprotein (AFP) strip for the ultrasensitive and hand-held detection of NA samples. In detail, the target-initiated-Exo-III/Cas12a strategy realizes the signal amplification and liberates AFP from magnetic beads through the trans-cleavages of activated Cas12a toward the AFP aptamer. After magnetic separation and migration, the fluorescence signals of the test (FT) and control (FC) lines on the AFP strip were digitally output by the SPFD, and the FT/FC was employed for the quantitative analysis to minimize external disturbances and improve accuracy. We experimentally assessed the universe applicability of the proposed NA-POCT platform toward miRNA-155, 16S rRNA of Staphylococcus aureus, and ORF1a/b RNA of Covid-19 pseudovirus, achieving favorable detection limits of 42 aM, 18 CFU/mL, and 87 copies/μL, respectively. Moreover, its simplicity, universality, and admirable detection performance demonstrate a great potential in the aspect of rapidly transforming the existing POCT devices for multiple new applications at the time of need.

From Chips-in-Lab to Point-of-Care Live Cell Device: Development of a Microfluidic Device for On-Site Cell Culture and High-Throughput Drug Screening.

Live cell assays provide real-time data of cellular responses. In combination with microfluidics, applications such as automated and high-throughput drug screening on live cells can be accomplished in small devices. However, their application in point-of-care testing (POCT) is limited by the requirement for bulky equipment to maintain optimal cell culture conditions. In this study, we propose a POCT device that allows on-site cell culture and high-throughput drug screening on live cells. We first observe that cell viabilities are substantially affected by liquid evaporation within the microfluidic device, which is intrinsic to the polydimethylsiloxane (PDMS) material due to its hydrophobic nature and nanopatterned surface. The unwanted PDMS-liquid-air interface in the cell culture environment can be eliminated by maintaining a persistent humidity of 95-100% or submerging the whole microfluidic device under water. Our results demonstrate that in the POCT device equipped with a water tank, both primary cells and cell lines can be maintained for up to 1 week without the need for external cell culture equipment. Moreover, this device is powered by a standard alkali battery and can automatically screen over 5000 combinatorial drug conditions for regulating neural stem cell differentiation. By monitoring dynamic variations in fluorescent markers, we determine the optimal doses of platelet-derived growth factor and epidermal growth factor to suppress proinflammatory S100A9-induced neuronal toxicities. Overall, this study presents an opportunity to transform lab-on-a-chip technology from a laboratory-based approach to actual point-of-care devices capable of performing complex experimental procedures on-site and offers significant advancements in the fields of personalized medicine and rapid clinical diagnostics.

Diagnostic Performance of Point-of-Care High-Sensitivity Troponin in the Exclusion of Non-ST-Elevation Myocardial Infarction in the Emergency Department.

This study evaluates the diagnostic performance of high-sensitivity troponin using point-of-care testing (POCT) devices compared with main laboratory measurements for ruling out non-ST-elevation myocardial infarction (NSTEMI) in emergency department (ED) patients presenting with non-traumatic chest pain. This multicenter, observational, prospective, non-interventional study was conducted in two Spanish hospitals from 1 June to 31 December 2023 and included adult patients presenting with non-traumatic chest pain admitted to the ED. High-sensitivity troponin levels were measured using both the Siemens Atellica® VTLi POCT device and main laboratory testing, with data collected on analytical results and measurement times. Of the 201 patients who met the inclusion criteria, a significant correlation was observed between the POCT and laboratory assays. The area under the curve (AUC) of the ROC curve was consistently greater than 0.9, indicating a high diagnostic accuracy for ruling out NSTEMI. In addition, measurement times were significantly reduced using POCT compared to the core laboratory. These results suggest that high-sensitivity troponin POCT devices offer comparable diagnostic performance to traditional laboratory methods for the diagnosis of NSTEMI in the emergency department, potentially speeding up clinical decisions and optimizing resource utilization.

A novel indicator for lead poisoning beyond blood lead level: Facile diagnosis of lead poisoning using random urine with point-of-care testing

Lead (Pb) poisoning is estimated to account for 1 % of the global disease burden. The gold standard for diagnosing lead poisoning in human body relies on blood lead level (BLL), which is always performed in hospitals using expensive instruments. However, there are still many countries and regions with a lack of medical resources (without enough professional medical staff and analytical instruments). To achieve a facile diagnosis of lead poisoning by ordinary residents (without any expertise), this study conducted a research study on 810 participants to discover and validate a new lead poisoning indicator (creatinine-corrected urinary lead level, cULL) beyond BLL in non-invasive samples. A point-of-care testing (POCT) device to measure cULL was developed, equipped with liquid-phase microextraction and electromembrane extraction on a paper-based analytical device for on-site separation of lead and creatinine in the urine, using a smartphone for the quantification of analytes. The cULL as a novel indicator and the POCT device developed could be effective in reducing the risk of damage from lead contamination.

Point-of-Care Testing of Whole Blood for Liver Injury Auxiliary Diagnosis with Biothiols Activable Chemiluminescent Probe.

Liver injury significantly affects a patient's health and quality of life. However, timely and convenient diagnosis of this disease via whole blood detection remains challenging due to the lack of user-friendly and fast readout blood test methods. Herein, we developed such a method for the swift auxiliary diagnosis of liver injury via whole blood detection using a customed point-of-care testing (POCT) system consisting of a biothiols-activatable chemiluminescent probe and a hand-held POCT device. Biothiols served as the target to build the activable chemiluminescence probe due to their abnormal level in liver injury. Compared with fluorescent and electrical POCTs, this method is more convenient and has strong universality. By incorporating cyclodextrin via host-guest chemistry, we intensified chemiluminescence while mitigating chemical hemolysis caused by the dissolution of organic molecules, making this system suitable for whole blood analysis. Preliminary assessments in aqueous solutions, living cells, and mouse models confirmed its sensitivity, reliability, and feasibility. Simply mixing blood with the probe for 30 min yielded a clear signal readout within 15 s on the POCT device. Utilizing this portable detector, the reduced biothiol level was tested in 18 liver injury patient blood samples, and the results were similar to those measured by a commercial kit and in vivo imaging system. Thus, this work provides a universal platform for the fast and convenient detection of other biomarkers in whole blood samples and opens up possibilities for the rapid clinical diagnosis of diseases, enabling patients to conduct home self-examinations with ease.

A portable smartphone detection of ctDNA using MnB2 nanozyme and paper-based analytical device

The development of point-of-care testing (POCT) for circulating tumor DNA (ctDNA) is meaningful for the non-invasive cancers screening and diagnosis, particularly in resource-limited settings. The microfluidic paper-based analytical device (μPAD) provides an ideal platform, its application in ctDNA assays remains underexplored. In this work, a multifunctional μPAD was manufactured, which can enhance the efficiency and reduce the cost of ctDNA sensing. Additionally, a smartphone-based application analysis was fabricated for convenient, portable detection and colorimetric signal readout. Moreover, the novel oxidase-like MnB2 nanozyme was introduced in the sandwiches sensing strategy, utilizing its catalytic properties to effectively generate a colorimetric signal. The use of MnB2 nanozyme in sensing application is relatively novel, and its catalytic performance and mechanism was thoroughly evaluated via experiment and density functional theory (DFT) calculations. After optimizing the detection conditions, the proposed biosensor exhibited satisfactory results. Furthermore, the method was successfully used to detect ctDNA in tumor cell lysates and peripheral blood samples from tumor-bearing mice. The results were consistent with standard qPCR method, affirming the reliability of our POCT analysis device in ctDNA detection. Thus, this work not only provides a paper-based POCT device and intelligent analysis tool for portable cancers diagnosis, but it also paves a new application path for MnB2 nanozyme in the sensing filed.

NiADA (Non-invasive Anemia Detection App), a Smartphone-Based Application With Artificial Intelligence to Measure Blood Hemoglobin in Real-Time: A Clinical Validation.

Background Anemia is a severe public health problem in India affecting more than half of the population. To reduce its burden on the population, the Government of India under the Anemia Mukt Bharat program has adopted a monitoring strategy for the diagnosis and treatment of anemia. Point-of-care testing (POCT) devices play a pivotal role in testing hemoglobin at a community level where sophisticated laboratory instruments are not available. The majority of the currently available POCT devices are invasive in nature which have their own limitations. A non-invasive method of hemoglobin estimation will address many of the limitations of an invasive POCT instrument, which will further improve people's acceptability for hemoglobin testing. The Non-Invasive Anemia Detection App (NiADA) (Monere AI Private Limited, Kolkata, West Bengal, India), a non-invasive POCT application, uses artificial intelligence (AI) to predict the hemoglobin level from lower eyelid images. This real-time, point-of-care, low-cost solution uses a custom computer vision deep-learning algorithm to determine blood hemoglobin value. Method The study validates an AI-based smartphone application NiADAagainst laboratory hemoglobin estimation and a widely used point-of-care hemoglobin estimation instrument (HemoCue Hb 301; HemoCue AB, Angelholm, Skane County, Sweden). The study was conducted in a tertiary care hospital in Eastern India and recruited a total of 556 participants. These included 58 pediatric patients, 51 pregnant women, 214 adult females, and 224 adult males. Statistical analysis was performed using Python (Python Software Foundation, Wilmington, Delaware, United States). A p-value of < 0.05 was taken to be significant. Result The mean difference observed between NiADA and laboratory-estimated hemoglobin values came out to be -0.29 g/dL and -0.89 g/dL for adult females and males respectively, and 0.61 g/dL for pregnant women and -0.69g/dL for the pediatric population. The limits of agreement for NiADA were narrow at 2.77 to -2.18 g/dL for adult females, 3.76 to -1.96 g/dL for adult males, 1.89 to -3.29 g/dL for pregnant women, and 3.28 to -2.08 g/dL for the pediatric population. The sensitivity and specificity of the NiADA application against the laboratory estimation method were 75.8% and 53.8% for adult females, 70.0% and 48.3% for adult males, 23.8% and 90% for pregnant females, and 75% and 57% for the pediatric population. Conclusion As a non-invasive application, NiADA's performance is satisfactory and comparable with minimally invasive tools like HemoCue Hb 301 and otherPOCT devices.

NFC Smartphone-Based Electrochemical Microfluidic Device Integrated with Nanobody Recognition for C-Reactive Protein.

Point-of-care testing (POCT) devices play a crucial role as tools for disease diagnostics, and the integration of biorecognition elements with electronic components into these devices widens their functionalities and facilitates the development of complex quantitative assays. Unfortunately, biosensors that exploit large conventional IgG antibodies to capture relevant biomarkers are often limited in terms of sensitivity, selectivity, and storage stability, considerably restricting the use of POCT in real-world applications. Therefore, we used nanobodies as they are more suitable for fabricating electrochemical biosensors with near-field communication (NFC) technology. Moreover, a flow-through microfluidic device was implemented in this system for the detection of C-reactive protein (CRP), an inflammation biomarker, and a model analyte. The resulting sensors not only have high sensitivity and portability but also retain automated sequential flow properties through capillary transport without the need for an external pump. We also compared the accuracy of CRP quantitative analyses between commercial PalmSens4 and NFC-based potentiostats. Furthermore, the sensor reliability was evaluated using three biological samples (artificial serum, plasma, and whole blood without any pretreatment). This platform will streamline the development of POCT devices by combining operational simplicity, low cost, fast analysis, and portability.

Point-of-care monitoring of milk quality by rapid Immunofluorescence with mechanical deformation of the hydrogel microspheres

Point-of-care testing (POCT) of chloramphenicol (CAP) in fresh milk from private ranches is essential to ensure food safety. It’s still a great challenge to meet simultaneously rapid and accurate during POCT of CAP. Here, we present a POCT device integrating hydrogel microsphere immunoassay and smartphone Fourier analysis for fast and sensitive detection of CAP. Based on the excellent biocompatibility and outstanding mechanical properties of hydrogel microspheres (100 μm), the antibody activity can be maintained and the mechanical deformation of the hydrogel cross-linking lattice is induced by squeezing to accelerate the antigen-antibody reaction of CAP and anti-CAP antibodies. The signal-to-noise ratio of the detection result is optimized adaptively by a designed microsphere Fourier analysis algorithm for precise CAP concentration detection. The results show that the method decreases incubation time from 60 min to 25 min and meets detection limit requirements of industrial production (0.05 ng/mL, with a dynamic range of 0.05–8 ng/mL). This method not only achieves rapid and accurate on-site detection of CAP in milk but also applies to other low concentrations of harmful substances detection in food field.

Point-of-care testing: a critical analysis of the market and future trends

Point-of-care testing (POCT) involves conducting diagnostic tests outside the laboratory. These tests are utilized for their quick and reliable results in detecting chronic diseases and acute infections. We examined the historical market value trends of the POCT industry and projected its future growth. POCT devices offer several advantages, such as portability, no specific storage requirements, and simplicity of use. However, issues such as inaccurate results can reduce demand for POCT compared to traditional laboratory testing alternatives. While the benefits of POCT are clear, it’s important to acknowledge the challenges. The accuracy of POCT devices can be compromised due to factors such as user error, environmental conditions, and limitations in technology. Furthermore, the cost-effectiveness of these devices is often a concern, particularly in resource-limited settings. The regulatory landscape for POCT is also complex and varies by region, which can pose challenges for manufacturers and end-users. Improvements in POCT devices’ sensitivity, specificity, cost, and turnaround time for test results could enhance their utility. Enhancements to a POCT device should be considered if they are economically viable and lead to a significant increase in demand. Our financial analysis of the POCT market revealed a positive growth trend. We identified potential areas for growth that could help the industry progress and expand in line with its projected growth in the coming years. The industry could focus on integrating intelligent technologies into POCT devices and collaborating with the innovative technology sector to increase revenue. It could also develop more sensitive and accurate POCT devices for non-communicable diseases. Another potential area of growth is in diseases that require continuous patient monitoring but where conventional clinical testing is time-consuming. Enhancing the POCT devices used in these areas could revolutionize medical diagnosis and potentially save many lives, provided they meet clinical standards.

Improvement of point of care testing device for accurate whole blood glucose measurement in early neonates.

It is important that blood glucose concentrations be accurately and conveniently measured in infants. However, especially in the early neonatal period, point-of-care testing devices used for adults may not accurately measure blood glucose concentrations in neonates. In Study 1, the accuracy of neonatal whole-blood glucose measurements was evaluated for the existing glucose analyser Glutest Mint® (hereinafter MINT1; Sanwa Kagaku Kenkyusho, Nagoya, Japan) by comparing the data with reference blood glucose concentrations. In Study 2, we used MINT2, which was modified based on the findings from Study 1, to measure whole-blood glucose concentrations in newborns, and the accuracy of the measurements was compared with that of MINT1. Blood glucose concentrations were measured in 100 infants each in Study 1 and 2. In Study 1, the whole-blood glucose concentrations measured using MINT1 were found to be significantly lower than the reference blood glucose concentrations in early neonates. The results of Study 1 suggested that characteristics of erythrocyte membranes in early neonates affected the measurements. Therefore, we conducted Study 2 using MINT2, which was modified to be less susceptible. MINT2 was found to accurately measure whole-blood glucose concentrations in the early neonatal period. The study showed that the point-of-care testing device could be improved to allow for accurate whole-blood glucose measurements in the early neonatal period.