Point-of-care Testing Systems Research Articles

B-201 Clinical Performance Evaluation of IRON-qPCR™ RV, a Novel Molecular POCT system, for the Qualitative Detection of Respiratory Viruses in Nasopharyngeal Swab

Abstract Background The availability of Point-of-Care testing (POCT) based on molecular diagnostics to test simultaneously for multiple respiratory viruses is very limited though significant progress has been made in molecular testing for COVID-19 during the pandemic. Considering the similar symptoms presented by patients infected with various respiratory pathogens, it is crucial to have multiple POCT systems capable of detecting multiple respiratory pathogens while distinguishing SARS-CoV-2 from other pathogens. To meet the growing demand for multiplex testing for respiratory pathogens, a molecular POCT, IRON-qPCR™ RV has been developed. IRfON-qPCR™ RV is a multiplex real-time RT-PCR assay designed for the qualitative detection and differentiation of SARS-CoV-2, Influenza A, Influenza B, RSV-A, and RSV-B RNA from human nasopharyngeal swab specimens. The IRON-qPCR™ proceeds the entire process automatically from nucleic acid extraction to real-time RT-PCR within 40 minutes. The main goal of this study is to evaluate the clinical performance of IRON-qPCR™ RV in comparison with other assays and kits using nasopharyngeal swab samples. Methods To assess the clinical performance of the IRON-qPCR™ RV, specimen collection and evaluation were conducted at a clinical institution in France, utilizing a total of 980 nasopharyngeal swab samples. The comparators used were the Xpert® Xpress CoV-2/Flu/RSV plus Kit and the RealStar® RSV RT-PCR Kit 3.0. Since RSV subtypes are not distinguished by the Xpert kit, all RSV without subtype distinction were compared. Additionally, RealStar kit was used to compare the results of IRON-qPCR™ RV for RSV subtypes A and B. Clinical samples showing discrepancies between Xpert and RealStart, and the IRON-qPCR™ RV were further analyzed using Allplex™ SARS-CoV-2/FuA/FluB/RSV Assay and sequencing. Results Through the comparison of clinical performance of the IRON-qPCR™ RV with Xpert for SARS-CoV-2, Influenza A, and Influenza B in nasopharyngeal swab samples, the clinical sensitivity was analyzed to be over 95.5%, and the clinical specificity was over 99.6%. For RSV, compared to Xpert, the clinical sensitivity was analyzed to be 96.9%, and the clinical specificity was 98.9%. Furthermore, in comparison with RealStar, the clinical sensitivity and specificity of IRON-qPCR™ RV for RSV-A were determined to be 96.2% and 100%, respectively, and the clinical sensitivity and specificity for RSV-B were 96.0% and 100%. Additionally, discrepant samples in comparison with Xpert were further tested using the Allplex as a resolver kit. The result showed that the clinical sensitivity and specificity of IRON-qPCR™ RV for SARS-CoV-2, Influenza A, and Influenza B were over 98.3% and 100%. For RSV, the clinical sensitivity and specificity were 99.5% and 99.1%. Conclusions The clinical performance of IRON-qPCR™ RV was analyzed with the clinical sensitivity of over 95% and the clinical specificity of over 99%. Upon analysis including the results of the resolver kit for discrepant samples, increased clinical sensitivity and specificity were determined. The results of this study strongly support that the IRON-qPCR™ RV is a reliable POCT system for the simultaneous detection and differentiation of multiple respiratory viruses. Furthermore, it is applicable to district hospitals as well as clinical laboratories for accurate and timely testing.

Diagnostic accuracy of salivary active matrix metalloproteinase (aMMP)-8 point-of-care test for detecting periodontitis in adults: A systematic review and meta-analysis.

To determine the accuracy of salivary active matrix metalloproteinase (aMMP)-8 point-of-care test (POCT) for detecting periodontitis in adults, through meta-analysis. Diagnostic studies evaluating the accuracy of salivary/oral rinse aMMP-8 POCT for detecting periodontitis in adults, when compared with clinical examination, were considered eligible. A comprehensive search was performed up to 31 August 2023 through five databases. Quality Assessment of Diagnostic Accuracy Studies 2 was utilized to evaluate the methodological quality of the included articles. Meta-analysis was performed using Bayesian bivariate hierarchical model and subgroup analysis. From 368 screened studies, 6 studies (4 cross-sectional and 2 longitudinal studies) were included in the meta-analysis. Overall, the pooled sensitivity and specificity of salivary aMMP-8-POCT for detecting periodontitis were 0.63 (95% CI: 0.41-0.82) and 0.84 (95% CI: 0.65-0.95), respectively. Subgroup analyses revealed that the 95% CI for oral fluid types, predefined diagnostic thresholds and the POCT systems largely overlapped, indicating that the differences between them may not be significant. Salivary aMMP-8 POCT shows fair accuracy for detecting periodontitis. The diagnostic accuracy cannot be significantly influenced by the types of oral fluids, predefined diagnostic thresholds or the specific POCT systems used. More research is needed to confirm the clinical utility and implementation of aMMP-8 POCT in the diagnosis of periodontitis.

Investigation of the Effect of 70 Potential Interferents on Measurement Results of Two Blood Glucose Monitoring Systems.

Reliable blood glucose (BG) measurements are important for people with diabetes to manage their therapy as well as in point-of-care testing (POCT) performed by health care professionals to monitor BG of patients or even to diagnose diabetes. Among other factors, endogenous and exogenous substances present in blood samples can impact the measurement results. To ensure and prove that blood glucose monitoring systems (BGMSs) are robust in terms of potential interferents, manufacturers have to perform extensive evaluations. An interference screening test was performed for three reagent system lots of a POCT system and of a BGMS for self-monitoring of BG. A paired-difference approach based on ISO 15197:2013 and CLSI guideline EP07 was used with venous whole blood samples at two different glucose concentrations. Seventy potential interferents expected to be common in people with diabetes were evaluated. The interference effects were determined as normalized biases between test samples and corresponding control samples. For 69 of the 70 investigated potential interferents, both systems met the predefined acceptance criteria, with the normalized biases falling within ±10 mg/dL or ±10% at glucose concentrations ≤100 mg/dL or >100 mg/dL, respectively, for each of the three evaluated reagent system lots. The BGMS investigated in this study were found to be robust with respect to the 70 evaluated potential interferents. Interference effects were observed only for N-Acetyl-L-cysteine. Extensive evaluations of potential interfering factors can make an important contribution to ensure reliability of BGMS.

Surface‐Enhanced Raman Spectroscopy‐Based Optical Biosensor for Liquid Biopsy: Toward Precision Medicine

AbstractLiquid biopsy is regarded as a promising strategy for assisting precision medicine because of its convenience, noninvasiveness, and ability to overcome tumor heterogeneity and achieve early detection. Recently, impressive advancements in plasmonic biosensors, artificial intelligence, and portable Raman equipment have yielded unprecedented progress in surface‐enhanced Raman spectroscopy (SERS)–based point‐of‐care testing (POCT) systems for liquid biopsy. The development of these systems presents a paradigm shift in on‐site liquid biopsy applications by leveraging the unique benefits of efficiency, fast analysis, portability, affordability, and user‐friendliness. Herein, these advances are introduced over the last 3 years in the field of SERS‐based POCT systems for labeled and label‐free biomarker analysis in body fluids, including tumor circulating proteins and cells, exosomes, micro‐RNA, and circulating tumor DNA. Additionally, powerful machine learning algorithms (including deep learning algorithms) are integrated with SERS to effectively extract potential data features and generate precise diagnostic models. The review highlights the use of handheld and portable Raman devices in significantly promoting the application of SERS‐based POCT in clinical scenarios. Finally, the review outlines the challenges and future perspectives of this technology.

Development of enzyme-inorganic hybrid nanoflower-modified electrodes and a smartphone-controlled electrochemical analyzer for point-of-care testing of salivary amylase in saliva.

Quantitation of salivary alpha-amylase (sAA) plays a significant role in not only theoretical studies but also clinical practice. This study reports a quantitative point-of-care testing (POCT) system for sAA quantitation anywhere, anytime and by anyone, which consists of customized electrodes and a smartphone-controlled electrochemical analyzer. Organic-inorganic hybrid nanoflowers (NFs) encapsulating α-glucosidase (AG) and glucose dehydrogenase (GDH) have been synthesized and modified onto screen-printed electrodes (SPCEs) to fabricate the customized electrodes. The SPCEs integrated with the smartphone-controlled electrochemical analyzer exhibit good analytical performance for sAA with a low detection limit of 5.02 U mL-1 and a wide dynamic range of 100-2000 U mL-1 using chronoamperometry. The reported POCT system has been successfully demonstrated for quantitation of sAA in clinical saliva samples, and the quantitation results correlated well with those of the Bernfeld method which is extensively used in clinics. More importantly, this study reveals the great potential of sAA as an early warning indicator of abnormal glucose metabolism in obese individuals. Considering the non-invasive saliva sampling process as well as the easy-to-use and cost-effectiveness features of this quantitative POCT system, quantitation of salivary sAA at home by laypersons might become an appealing choice for obese individuals to monitor their glucose metabolism status anytime.

Design and application of a point-of-care testing system for triple detection of SARS-CoV-2, influenza A, and influenza B.

To mitigate the continued impact of SARS-CoV-2, influenza A, and influenza B viruses on human health, a smartphone-based point-of-care testing (POCT) system was designed to detect respiratory pathogens through a nucleic acid test. This compact, light-weight, highly automated, and universal system enables the differential diagnosis of SARS-CoV-2, influenza A, and influenza B in approximately 30min in a single-tube reaction. Numerous hospitals and disease control and prevention center assessed the triple POCT system's detection threshold, sensitivity, specificity, and stability, and have concluded that all the assessments were comparable to those of fluorescent quantitative polymerase chain reaction (PCR)-based testing. The triple POCT system is suitable as an onsite rapid-diagnosis device, as well as for pathogen screening at airports and customs.

Point-Of-Care Ultra-Portable Single-Molecule Bioassays for One-Health.

Screening asymptomatic organisms (humans, animals, plants) with a high-diagnostic accuracy using point-of-care-testing (POCT) technologies, though still visionary holds great potential. Convenient surveillance requires easy-to-use, cost-effective, ultra-portable but highly reliable, in-vitro-diagnostic devices that are ready for use wherever they are needed. Currently, there are not yet such devices available on the market, but there are a couple more promising technologies developed at readiness-level 5: the Clustered-Regularly-Interspaced-Short-Palindromic-Repeats (CRISPR) lateral-flow-strip tests and the Single-Molecule-with-a-large-Transistor (SiMoT) bioelectronic palmar devices. They both hold key features delineated by the World-Health-Organization for POCT systems and an occurrence of false-positive and false-negative errors <1-5% resulting in diagnostic-selectivity and sensitivity >95-99%, while limit-of-detections are of few markers. CRISPR-strip is a molecular assay that, can detect down to few copies of DNA/RNA markers in blood while SiMoT immunometric and molecular test can detect down to a single oligonucleotide, protein marker, or pathogens in 0.1mL of blood, saliva, and olive-sap. These technologies can prospectively enable the systematic and reliable surveillance of asymptomatic ones prior to worsening/proliferation of illnesses allowing for timely diagnosis and swift prognosis. This could establish a proactive healthcare ecosystem that results in effective treatments for all living organisms generating diffuse and well-being at efficient costs.

Traceable value of immunoglobulin G against receptor-binding domain of SARS-CoV-2 confirmation and application to point-of-care testing system development.

A highly purified and bioactive immunoglobulin G monoclonal antibody against receptor-binding domain of SARS-CoV-2 (RBD-IgG-MAb) has been accurately quantified by amino acid determination using isotope dilution liquid chromatography-mass spectrometry. Absolute quantification of RBD-IgG-MAb was achieved by averaging 4 amino acid certified reference materials, which allows the quantitative value (66.1 ± 5.8 μg/L) to be traced to SI unit (mol). Afterwards, the RBD-IgG-MAb was employed as control and calibrationcompound for the development of a point-of-care testing (POCT) system based on colloidal gold lateral flow immunoassay, which aimed to rapidly and accurately detect the level of protective RBD-IgG after vaccination. Under the detection parameters, a sigmoidal curve has been plotted between signal intensity and the logarithmic concentration for quantitative detection with the limit of detection of about 0.39μg/mL. The relative standard deviations of intra-assay and inter-assay were lower than 2.3% and 14%, and the recoveries ranged from 87 to 100%, respectively. Fingertip blood samples from 37 volunteers after vaccination were analyzed by the POCT system; results showed that levels of RBD-IgG in 33 out of 37 samples ranged from 0.45 to 2.46μg/mL with the average level of 0.91μg/mL. The developed POCT system has been successfully established with the quantity-traceability RBD-IgG-MAb as control and calibration compound, and the scientific contribution of this work can be promoted to other areas.

A smartphone-powered photoelectrochemical POCT via Z-scheme Cu2O/Cu3SnS4 for dibutyl phthalate in the environmental and food

As a major hazardous additive released from microplastics and nanoplastics, identifying dibutyl phthalate (DBP) in complex matrices attracts a growing concern in environmental monitoring and food safety. For the first time, Cu2O/Cu3SnS4 nanoflower is prepared and serves as the photoactive material which can be constructed as a smartphone-based photoelectrochemical (PEC) point-of-care test (POCT). Effectively matching energy levels between Cu2O and Cu3SnS4 accelerated the transfer of photogenerated electron-hole pairs, significantly improving the intelligent PEC POCT performance. The novel Cu2O/Cu3SnS4 has proven to be the Z-scheme heterojunction by density functional theory calculation. A competitive immunoassay has been realized on a Cu2O/Cu3SnS4 modified electrode, dramatically decreasing the photocurrent signal and enhancing POCT sensitivity. The smartphone has been used to record and transfer PEC results. Under optimal conditions, the PEC POCT exhibited a satisfying linear range (0.04–400 ng/mL) and a low detection limit of 7.94 pg/mL in real samples, together with excellent stability, repeatability, reproducibility and selectivity. The PEC POCT system provides good performance and practicability in determining DBP in water and edible oil samples. This proposal provides a practical strategy for the intelligent POCT for environment monitoring and food safety.

A portable system for economical nucleic acid amplification testing.

Introduction: Regular and rapid large-scale screening for pathogens is crucial for controlling pandemics like Coronavirus Disease 2019 (COVID-19). In this study, we present the development of a digital point-of-care testing (POCT) system utilizing microfluidic paper-based analytical devices (μPADs) for the detection of SARS-CoV-2 gene fragments. The system incorporates temperature tuning and fluorescent detection components, along with intelligent and autonomous image acquisition and self-recognition programs. Methods: The developed POCT system is based on the nucleic acid amplification test (NAAT), a well-established molecular biology technique for detecting and amplifying nucleic acids. We successfully detected artificially synthesized SARS-CoV-2 gene fragments, namely ORF1ab gene, N gene, and E gene, with minimal reagent consumption of only 2.2μL per readout, representing a mere 11% of the requirements of conventional in-tube methods. The power dissipation of the system was low, at 6.4W. Results: Our testing results demonstrated that the proposed approach achieved a limit of detection of 1000 copies/mL, which is equivalent to detecting 1 copy or a single RNA template per reaction. By employing standard curve analysis, the quantity of the target templates can be accurately determined. Conclusion: The developed digital POCT system shows great promise for rapid and reliable detection of SARS-CoV-2 gene fragments, offering a cost-effective and efficient solution for controlling pandemics. Its compatibility with other diagnostic techniques and low reagent consumption make it a viable option to enhance healthcare in resource-limited areas.

Methylene-Blue-Encapsulated Metal-Organic-Framework-Based Electrochemical POCT Platform for Multiple Detection of Heavy Metal Ions in Milk.

Considering the high risk of heavy metal ions (HMIs) transferring through the food chain and accumulating in milk, a flexible and facile point-of-care testing (POCT) platform is urgently needed for the accurate, sensitive, and highly selective on-site quantification of multiple HMIs in milk. In this work, a cost-effective disk with six screen-printed electrodes (SPEs) was designed for hand-held electrochemical detection. Metal organic frameworks (MOFs) were adopted to amplify and enhance the electrochemical signals of methylene blue (MB). Using differential pulse voltammetry (DPV) methods, low limits of detection for four HMIs (Cd2+, 0.039 ppb; Hg2+, 0.039 ppb; Pb2+, 0.073 ppb; and As3+, 0.022 ppb) were achieved within four minutes. Moreover, the quantitative POCT system was applied to milk samples. The advantages of low cost, ease of on-site implementation, fast response, and accuracy allow for the POCT platform to be used in practical monitoring applications for the quantitation of multiple HMIs in milk samples.

A sample-preparation-free, point-of-care testing system for in situ detection of bovine mastitis.

We present a highly integrated point-of-care testing (POCT) device capable of immediately and accurately screening bovine mastitis infection based on somatic cell counting (SCC). The system primarily consists of a homemade cell-counting chamber and a miniature fluorescent microscope. The cell-counting chamber is pre-embedded with acridine orange (AO) in advance, which is simple and practical. And then SCC is directly identified by microscopic imaging analysis to evaluate the bovine mastitis infection. Only 4 μL of raw bovine milk is required for a simple sample testing and accurate SCC. The entire assay process from sampling to result in presentation is completed quickly within 6min, enabling instant "sample-in and answer-out." Under laboratory conditions, we mixed bovine leukocyte suspension with whole milk and achieved a detection limit as low as 2.12 × 104 cells/mL on the system, which is capable of screening various types of clinical standards of bovine milk. The fitting degrees of the proposed POCT system with manual fluorescence microscopy were generally consistent (R2 > 0.99). As a proof of concept, four fresh milk samples were used in the test. The average accuracy of somatic cell counts was 98.0%, which was able to successfully differentiate diseased cows from healthy ones. The POCT system is user-friendly and low-cost, making it a potential tool for on-site diagnosis of bovine mastitis in resource-limited areas.

A fluorescence point-of-care testing system for sample-to-answer detection of immunoglobulin E

In the work, a novel fluorescence point-of-care testing (POCT) system was developed for sample-to-answer detection of immunoglobulin E (IgE), which is the first time that a cloth material has been applied to the fluorescence detection of proteins. The system included an lateral/vertical flow-based microfluidic (LVFM) model, POCT detector, and smartphone-based data processing module. In the LVFM model, the non-woven cloth and screen-printing methods were applied to break the restrictions of traditional lateral flow strips on nitrocellulose membrane material and fabrication method. The 3D-printed POCT detector was used to supply a dark environment, with advantages of small volume, lightweight, and being easy-to-use. The smartphone-based data processing module was applied for image acquisition, image analysis and data display. After the fluorescent image was taken, the image analysis was carried out by the self-developed APP. By using the proposed POCT system, on the optimized conditions, the desired IgE detection was obtained, with a linear dynamic detection range of 10–1000 ng mL−1, and detection limit of 8.5 ng mL−1. In addition, the presented system showed good selectivity, repeatability and stability, and had the potential to be used in the field of detection of allergic diseases.

Visual Detection of Stem-Loop Primer Amplification (SPA) Products without Denaturation Using Peroxidase-like DNA Machines (PxDM).

Rapid, inexpensive, and accurate determination of nucleic acids is a decisive factor in evaluating population's health and monitoring treatment at point-of-care (POC) settings. Testing systems with visual outputs can provide instrument-free signal detection. Isothermal amplification technologies can substitute conventional polymerase chain reaction (PCR) testing due to compatibility with the POC diagnostic. Here, we have visually detected DNA fragments obtained by stem-loop-primer-assisted isothermal amplification (SPA), but not those obtained by PCR or LAMP amplification using DNA nanomachines with peroxidase-like activity (PxDM) with sensitivity to a single nucleotide substitution. Compared to the diagnostics with conventional loop-mediated isothermal amplification (LAMP), the PxDM method produces no false positive signals with the non-specific amplification products. The study suggests that PxDM, in conjunction with SPA isothermal amplification, can become a valid platform for POC testing systems.

Smartphone-assisted detection of monocrotophos pesticide using a portable nano-enabled chromagrid-lightbox system towards point-of-care application

With the aim of monocrotophos pesticides detection in environmental and food samples at point-of-care (PoC) application, this research, for the first time, explores silica alcogel as an immobilization matrix to support the development of in-house customized nano-enabled “chromagrid-lighbox” as a sensing system. This system is fabricated using laboratory waste materials and demonstrates the detection of highly hazardous monocrotophos pesticide using a smartphone. Nano-enabled chromagrid is a chip-like assembly filled with silica alcogel -a nanomaterial (hence the name “nano-enabled” chromagrid), and “chromogenic reagents” which is required for the enzymatic detection of monocrotophos. Lightbox is the imaging station fabricated to provide constant lighting conditions to the chromagrid to capture accurate colorimetric data. The silica alcogel used in this system was synthesized from Tetraethyl orthosilicate (TEOS) via a sol-gel method and characterized using advanced analytical techniques. Further, three chromagrid assays were developed for the optical detection of monocrotophos with a low detection limit (LOD) at 0.421 ng ml−1 (by α-NAc chromagrid assay), 0.493 ng ml−1 (by DTNB chromagrid assay) and 0.811 ng ml−1 (by IDA chromagrid assay). The developed novel PoC chromagrid-lightbox system is capable of on-site detection of monocrotophos in environmental as well as food samples. This system is able to be manufacture prudently using recyclable waste plastic. Overall, such developed eco-friendly PoC testing system will surely manage rapid detection of monocrotophos pesticide needed for environmental and sustainable agricultural management.

Real-life evaluation of hypersensitive I-troponin on a point-of care analyser in an emergency unit

European Society of Cardiology (ESC) guidelines allow to perform rapid rule-in and rule-out algorithm with rapid troponin kinetics for the management of suspected Non ST-elevation acute coronary syndrome. These recommendations allow the use of point-of-care testing (POCT) systems provided that they have sufficient analytical performance. The aim of our study was to evaluate in real life the feasibility and performance of using a high sensitivity cardiac troponin I POCT system assay (hs-cTnI, Atellica® VTLi, Siemens) compared to high sensitivity cardiac troponin T values (hs-cTnT, e602®, Roche) obtained for patients admitted to emergency department. Analytical verification showed a coefficient of variation below 10% for hs-cTnI. Comparison of both troponins was moderate (r=0.7). The study included 117 patients with a median age of 65 years, 30% had renal failure and 36% presented with chest pain. In this study, the hs-cTnT value was, more often, higher than the 99th percentile than the hs-cTnl value, even for an age-adjusted 99th percentile hs-cTnT value. The concordance of the results was moderate (Cohen's Kappa: 0.54), age remaining the most important explanatory value of discordance. Only hs-cTnT had a predictive value for hospitalization. We did not observe any interpretation discrepancies for patients who had troponin kinetics. This study confirms the feasibility of using a POCT analyzer in the emergency department, provided that it performs high sensitivity troponin. However, some data are missing to be able to use it in the framework of rapid algorithm. Finally, the implementation of POCT requires collaboration between biologists and emergency physicians in terms of organization and interpretation of values, for the overall benefit of the patient.

Coupling ELISA to smartphones for POCT of chronic and congenital Chagas disease

Chagas disease (CD) affects about 7 million people worldwide, presents a large prevalence in Latin America, and is growing in the rest of the world, where congenital CD is the main mode of transmission. Point-of-care testing (POCT) methods are increasingly required to ease early diagnostics and increase treatment success. This work presents the development and validation of a smartphone-integrated ELISA-based POCT system for the detection of both chronic and congenital CD. Expensive and bulky equipment used for ELISA in conventional laboratories was replaced as follows. A miniaturized device was fabricated for incubation of commercial ELISA plates, achieving ∼±1 °C uniformity and stability. The ELISA plate reader was replaced by smartphone camera and image processing, comprising algorithms to account for variability sources and spatial light non-uniformity; thus, additional hardware like a dark-box is not required. The agreement between samples classified with this novel reading method vs. ELISA plate reader was found to be 99.7% and 95.4% for chronic and congenital CD, respectively. Furthermore, a smartphone application was designed and implemented to guide the user during the assay, provide connectivity, and access databases, facilitating patient monitoring and health-policy making. The whole system is aimed to be used as a practical diagnostic tool in primary health care settings, as well as to facilitate patients’ follow-up to provide better treatment. Concerning the technology itself, the proposed POCT platform is versatile enough to be readily adapted for the detection of other infectious diseases.

Recent advances in point-of-care testing of COVID-19.

Advances in microfluidic device miniaturization and system integration contribute to the development of portable, handheld, and smartphone-compatible devices. These advancements in diagnostics have the potential to revolutionize the approach to detect and respond to future pandemics. Accordingly, herein, recent advances in point-of-care testing (POCT) of coronavirus disease 2019 (COVID-19) using various microdevices, including lateral flow assay strips, vertical flow assay strips, microfluidic channels, and paper-based microfluidic devices, are reviewed. However, visual determination of the diagnostic results using only microdevices leads to many false-negative results due to the limited detection sensitivities of these devices. Several POCT systems comprising microdevices integrated with portable optical readers have been developed to address this issue. Since the outbreak of COVID-19, effective POCT strategies for COVID-19 based on optical detection methods have been established. They can be categorized into fluorescence, surface-enhanced Raman scattering, surface plasmon resonance spectroscopy, and wearable sensing. We introduced next-generation pandemic sensing methods incorporating artificial intelligence that can be used to meet global health needs in the future. Additionally, we have discussed appropriate responses of various testing devices to emerging infectious diseases and prospective preventive measures for the post-pandemic era. We believe that this review will be helpful for preparing for future infectious disease outbreaks.

Tape integrated self-designed microfluidic chip for point-of-care immunoassays simultaneous detection of disease biomarkers with tunable detection range

Multiple biomarkers to diagnose the combined manifestations of a patient's disease are an indispensable guide in point-of-care testing (POCT) and clinical applications. Currently, multiplex determination of molecules at different concentrations usually requires assays with adjustable detection ranges. Here, for the first time, commercially available 3M tapes, Tape 610, Tape 810, Tape 600, are integrated into a self-designed key valve microfluidic chip (KVMC) to construct a Tape-based KVMC. Interestingly, 3M tapes with different absorption tunability for the encapsulated antibodies have been used in KVMC as substrate to enable detection of diseases biomarkers in serum ranging from pg mL−1 to μg mL−1. The Tapes antibody layer in the chip has been successfully developed without sophisticated modifications, and the detection probe can be used for a wide range of detection of three biomarkers without multiple modifications and amplification. Automated, multiplexed, simultaneous bioassays of clinically relevant inflammatory biomarkers are performed in the Tape-based KVMC POCT system, with a limit of detection (LOD) of 0.23 μg mL−1 for C-reactive protein (CRP), 0.14 ng mL−1 for procalcitonin (PCT), and 12.53 pg mL−1 for interleukin-6 (IL-6), respectively, which offers a desirable strategy for the early clinical diagnosis of sepsis. The developed Tape-based KVMC possesses high sensitivity and excellent selectivity for three biomarkers in undiluted human serum samples, providing the foundation for the application of chip POCT in clinical and field precision diagnostics.

Detection of micro-RNA by a combination of nucleic acid sequence-based amplification and a novel chemiluminescent pyrophosphate assay.

Micro-RNA has attracted much attention as a biomarker for disease progression and malignancy. A compact, simple, rapid, and highly sensitive method is required to perform simple genetic analyses, such as point-of-care testing (POCT), at the clinic or bedside. Nucleic acid sequence-based amplification (NASBA) is a specific amplification method for a single-stranded RNA fragment that is useful for the highly sensitive detection of miRNAs. In this work, we developed a novel miRNA analytical system for POCT by combining the NASBA and chemiluminescence methods. Because the NASBA reaction is conducted at a constant temperature (41°C) and detection by chemiluminescence reaction does not require a light source, these methods could be combined to amplify 100 ng/assay miRNA. This combined miRNA detection method could be useful for the future development of compact POCT systems.