Rapid photothermal assay for ultrasensitive point-of-care detection of tumor markers based on a filter membrane.

An ultrasensitive photothermal assay was designed for point-of-care testing (POCT) of tumor markers based on a filter membrane. Firstly, Cu2-xSe was successfully encapsulated in liposome spheres with biotin on the surface and connected to carcinoembryonic antigen (CEA) aptamer with 3'end modified biotin by streptavidin. Secondly, the CEA antibody was successfully modified on the surface of the nitrocellulose membrane through simple incubation. Finally, the assay process was completed using a disposable syringe, and the temperature was recorded using a handheld infrared temperature detector. In the range 0-50 ng mL-1, the temperature change of the nitrocellulose membrane has a strong linear relationship with CEA concentration, and the detection limit is 0.097 ng mL-1. It is worth noting that the entire testing process can be easily performed in 10 min, much shorter than traditional clinical methods. In addition, this method was successfully applied to the quantitative determination of CEA levels in human serum samples with a recovery of 96.2-103.3%. This rapid assay can be performed by "one suction and one push" through a disposable syringe, which is simple to operate, and the excellent sensitivity reveals the great potential of the proposed strategy in the POCT of tumor biomarkers.

Multi-dimensional microfluidic paper-based analytical devices (µPADs) for noninvasive testing: A review of structural design and applications.

The rapid emergence of microfluidic paper-based devices as point-of-care testing (POCT) tools for early disease diagnosis and health monitoring, particularly in resource-limited areas, holds immense potential for enhancing healthcare accessibility. Leveraging the numerous advantages of paper, such as capillary-driven flow, porous structure, hydrophilic functional groups, biodegradability, cost-effectiveness, and flexibility, it has become a pivotal choice for microfluidic substrates. The repertoire of microfluidic paper-based devices includes one-dimensional lateral flow assays (1D LFAs), two-dimensional microfluidic paper-based analytical devices (2D µPADs), and three-dimensional (3D) µPADs. In this comprehensive review, we provide and examine crucial information related to paper substrates, design strategies, and detection methods in multi-dimensional microfluidic paper-based devices. We also investigate potential applications of microfluidic paper-based devices for detecting viruses, metabolites and hormones in non-invasive samples such as human saliva, sweat and urine. Additionally, we delve into capillary-driven flow alternative theoretical models of fluids within the paper to provide guidance. Finally, we critically examine the potential for future developments and address challenges for multi-dimensional microfluidic paper-based devices in advancing noninvasive early diagnosis and health monitoring. This article showcases their transformative impact on healthcare, paving the way for enhanced medical services worldwide.

Rapid single-tier serodiagnosis of Lyme disease.

Point-of-care serological and direct antigen testing offers actionable insights for diagnosing challenging illnesses, empowering distributed health systems. Here, we report a POC-compatible serologic test for Lyme disease (LD), leveraging synthetic peptides specific to LD antibodies and a paper-based platform for rapid, and cost-effective diagnosis. Antigenic epitopes conserved across Borrelia burgdorferi genospecies, targeted by IgG and IgM antibodies, are selected to develop a multiplexed panel for detection of LD antibodies from patient sera. Multiple peptide epitopes, when combined synergistically with a machine learning-based diagnostic model achieve high sensitivity without sacrificing specificity. Blinded validation with 15 LD-positive and 15 negative samples shows 95.5% sensitivity and 100% specificity. Blind testing with the CDC's LD repository samples confirms the test accuracy, matching lab-based two-tier results, correctly differentiating between LD and look-alike diseases. This LD diagnostic test could potentially replace the cumbersome two-tier testing, improving diagnosis and enabling earlier treatment while facilitating immune monitoring and surveillance.

Point-of-care testing device platform for the determination of creatinine on an enzyme@CS/PB/MXene@AuNP-based screen-printed carbon electrode.

Screen-printed carbon electrodes (SPCE) functionalized with MXene-based three-dimensional nanomaterials are reported for rapid determination of creatinine. Ti3C2TX MXene with in situ reduced AuNPs (MXene@AuNP) were used as a coreactant accelerator for efficient immobilization of enzymes. Creatinine could be oxidized by chitosan-embedded creatinine amidohydrolase, creatine amidinohydrolase, or sarcosine oxidase to generate H2O2, which could be electrochemically detected enhanced by Prussian blue (PB). The enzyme@CS/PB/MXene@AuNP/SPCE detected creatinine within the range 0.03-4.0 mM, with a limit of detection of 0.01 mM, with an average recovery of 96.8-103.7%. This indicates that the proposed biosensor is capable of detecting creatinine in a short amount of time (4 min) within a ± 5% percentage error, in contrast with the standard clinical colorimetric method. With this approach, reproducible and stable electrochemical responses could be achieved for determination of creatinine in serum, urine, or saliva. These results demonstrated its potential for deployment in resource-limited settings for early diagnosis and tracking the progression of chronic kidney disease (CKD).

C-reactive protein point-of-care testing in primary care-broader implementation needed to combat antimicrobial resistance.

This study presents the perspective of an international group of experts, providing an overview of existing models and policies and guidance to facilitate a proper and sustainable implementation of C-reactive protein point-of-care testing (CRP POCT) to support antibiotic prescribing decisions for respiratory tract infections (RTIs) with the aim to tackle antimicrobial resistance (AMR). AMR threatens to render life-saving antibiotics ineffective and is already costing millions of lives and billions of Euros worldwide. AMR is strongly correlated with the volume of antibiotics used. Most antibiotics are prescribed in primary care, mostly for RTIs, and are often unnecessary. CRP POCT is an available tool and has been proven to safely and cost-effectively reduce antibiotic prescribing for RTIs in primary care. Though established in a few European countries during several years, it has still not been implemented in many European countries. Due to the complexity of inappropriate antibiotic prescribing behavior, a multifaceted approach is necessary to enable sustainable change. The effect is maximized with clear guidance, advanced communication training for primary care physicians, and delayed antibiotic prescribing strategies. CRP POCT should be included in professional guidelines and implemented together with complementary strategies. Adequate reimbursement needs to be provided, and high-quality, and primary care-friendly POCT organization and performance must be enabled. Data gathering, sharing, and discussion as incentivization for proper behaviors should be enabled. Public awareness should be increased, and healthcare professionals' awareness and understanding should be ensured. Impactful use is achieved when all stakeholders join forces to facilitate proper implementation.

Economics of reducing response time to foreign-animal disease in the United States with point-of-care diagnostic tests.

BACKGROUND: As low probability events, United States producers, value chain actors, and veterinary services (VS) have limited experience with identifying foreign animal disease (FAD), which can allow FADs to spread undetected. Point-of-care (POC) diagnostic testing may help reduce the time from detecting an initial suspect case to implementing actionable interventions compared to the current approach of only using laboratory diagnostic testing for disease diagnosis and confirmation. To evaluate the value of the reduced response time, we compare the associated costs between the two diagnostic approaches while accounting for the uncertainty surrounding the size of a FAD event. METHODS: We apply a state-contingent approach (SCA) to model the uncertainty surrounding a FAD through alternative events, where the event defines the scale of outbreak size and its duration. We apply this approach within a cost-benefit framework (CBA) to determine the economic value from the two testing investment strategies to help explain the policymaker's response (and costs) to alternative FAD events while also considering the cost impacts on the producers from each event. RESULTS: Compared to the current laboratory strategy, a POC strategy that reduces response time by 0.5-days (swine, cattle scenarios) and 1.5-days (poultry scenario) may provide cost-saving to both producers and public response efforts. The benefit-cost analysis further suggests that despite the higher fixed costs to adopt the POC strategy, the swine and cattle sectors may benefit while the benefits may not be as pronounced in the poultry sector. DISCUSSION: POC testing that can reduce the time between detection and response during a FAD event may be a sound strategy for public expenditure and provide cost-savings for producers, especially when minimal fixed costs are incurred. However, to fully determine the value of POC testing, the consequences (costs) associated with potential actions if something goes wrong, (e.g. false positive results), should be considered in future studies.

Intermittent lysis on a single paper-based device to extract exosomal nucleic acid biomarkers from biological samples for downstream analysis.

As the role of exosomes in physiological and pathological processes has been properly perceived, harvesting them and their internal components is critical for subsequent applications. This study is a debut of intermittent lysis, which has been integrated into a simple and easy-to-operate procedure on a single paper-based device to extract exosomal nucleic acid biomarkers for downstream analysis. Exosomes from biological samples were captured by anti-CD63-modified papers before being intermittently lysed by high-temperature, short-time treatment with double-distilled water to release their internal components. Exosomal nucleic acids were finally adsorbed by sol-gel silica for downstream analysis. Empirical trials not only revealed that sporadically dropping 95 °C ddH2O onto the anti-CD63-modified papers every 5 min for 6 times optimized the exosomal nucleic acids extracted by the anti-CD63 paper but also verified that the whole deployed procedure is applicable for point-of-care testing (POCT) in low-resource areas and for both in vitro (culture media) and in vivo (plasma and chronic lesion) samples. Importantly, downstream analysis of exosomal miR-21 extracted by the paper-based procedure integrated with this novel technique discovered that the content of exosomal miR-21 in chronic lesions related to their stages and the levels of exosomal carcinoembryonic antigen originated from colorectal cancer cells correlated to their exosomal miR-21.

Added predictive value of prehospital measurement of point-of-care lactate in an adult general EMS population in Sweden: a multi-centre observational study.

BACKGROUND: Emergency medical services (EMS) personnel must rapidly assess and transport patients with time-sensitive conditions to optimise patient outcomes. Serum lactate, a valuable in-hospital biomarker, has become more accessible in EMS settings through point-of-care (POC) testing. Although POC lactate levels are valuable in specific patient groups, its broader application in EMS remains unclear. This study assessed the additional predictive value of POC lactate levels in a general adult EMS population. METHODS: This prospective observational study (March 2018 to September 2019) involved two EMS organisations in Västra Götaland, Sweden. Patients were triaged using the Rapid Triage and Treatment System (RETTS). POC lactate levels were measured using StatStrip Xpress devices. Non-consecutive patients who received EMS and were aged 18 years and above were available for inclusion if triaged into RETTS levels: red, orange, yellow, or green if respiratory rate of ≥ 22 breaths/min. Outcomes were adverse outcomes, including a time-sensitive diagnosis, sequential organ failure assessment (SOFA) score ≥ 2, and 30-day mortality. Statistical analyses included descriptive statistics, imputation, and regression models to assess the impact of the addition of POC lactate levels to a base model (comprising patient age, sex, presence of past medical conditions, vital signs, pain, EMS response time, assessed triage condition, and triage level) and a RETTS triage model. RESULTS: Of 4,546 patients (median age 75 [57, 84] years; 49% male), 32.4% had time-sensitive conditions, 12.5% met the SOFA criteria, and 7.4% experienced 30-day mortality. The median POC lactate level was 1.7 (1.2, 2.5) mmol/L. Patients with time-sensitive conditions had higher lactate levels (1.9 mmol/L) than those with non-time-sensitive conditions (1.6 mmol/L). The probability of a time-sensitive condition increased with increasing lactate level. The addition of POC lactate marginally enhanced the predictive models, with a 1.5% and 4% increase for the base and RETTS triage models, respectively. POC lactate level as a sole predictor showed chance-only level predictive performance. CONCLUSIONS: Prehospital POC lactate assessment provided limited additional predictive value in a general adult EMS population. However, it may be beneficial in specific patient subgroups, emphasizing the need for its judicious use in prehospital settings.

Diagnostic performance of an albuminuria point-of-care test in screening for chronic kidney disease among young people living with HIV in Uganda: a cross-sectional study.

OBJECTIVES: The main aim was to determine the diagnostic performance of an albuminuria point-of-care test (POC) for diagnosis of chronic kidney disease among young people living with HIV (YPLHIV) in Uganda. DESIGN: We conducted a cross-sectional study comparing the diagnostic performance of MicroalbuPHAN (Erba Lachema, Czech Republic), an albuminuria POC test against the laboratory-measured albumin and creatinine as the reference standard. SETTING: The study was set in seven HIV clinics in Kampala, Uganda that provide antiretroviral therapy to adults and children living with HIV. The study took place from April to August 2023. PARTICIPANTS: 497 YPLHIV aged 10-24 years who were diagnosed with HIV before 10 years of age were randomly selected from the HIV clinics. Pregnant YPLHIV were excluded. PROCEDURES: Participants provided a spot urine sample that was tested for albumin and creatinine using the POC and in the laboratory and proteinuria using urine dipstick. The sensitivity, specificity, negative and positive predictive values (NPV, PPV) of the POC versus the laboratory test were calculated, and factors associated with having a positive POC test were estimated using logistic regression. OUTCOME MEASURES: The primary outcome was a diagnosis of albuminuria defined as an albumin creatinine ratio above 30 mg/g. RESULTS: Of the 497 participants enrolled, 278 (55.9%) were female and 331 (66.8%) were aged 10-17 years. The POC test had a sensitivity of 74.5% (95% CI 70.6% to 78.4%) and specificity of 68.1% (95% CI 63.9% to 72.3%). The PPV was 21.5% (95% CI 17.8% to 25.1%) and the NPV was 95.8% (95% CI 94.0% to 97.6%), with an accuracy of 68.8%. There was strong evidence that a positive POC test was associated with having proteinuria (OR 2.82; 95% CI 1.89 to 4.22, p<0.001); body mass index <19.5 (OR 1.69 95% CI 1.17 to 2.45, p=0.005) and being male (OR 1.48; 95% CI 1.02 to 2.14, p=0.04). CONCLUSIONS: The albuminuria POC test had low sensitivity and specificity. However, it can be used to exclude kidney disease given its high NPV. It should be validated against the 24-hour urinary excretion rate to further determine its diagnostic performance.

Integrating point-of-care diabetes detection with lifestyle counselling in community settings: outcomes from Western Sydney, Australia.

INTRODUCTION: Early detection and prevention of type 2 diabetes and its complications are global health priorities. Optimal outcomes depend on individual awareness and proactive self-management of health risks. This study evaluates the effectiveness of a community-based diabetes detection and intervention program in a high-risk area in western Sydney, Australia. RESEARCH DESIGN AND METHODS: We collaborated with the Workers Lifestyle Group, Tamil Association Arts and Culture Association, and the National Aboriginal and Islanders Day Observance Committee to implement our program. Participants underwent HbA1C testing via point-of-care blood spot testing. They received personalized feedback, education on diabetes management, and were offered opportunities to enrol in lifestyle modification programs. Participants identified with pre-diabetes (HbA1C 5.7-6.4%) or diabetes (HbA1C > 6.4%) were advised to consult their General Practitioners (GPs). A follow-up questionnaire was distributed 3-8 months post-intervention to evaluate the programs usefulness and relevance and lifestyle changes implemented by the participants. RESULTS: Over eight months, 510 individuals participated. Of these, 19% had an HbA1C > 6.4%, and 38% had levels between 5.7 and 6.4%. Among those with diabetes, HbA1C levels ranged as follows: 56% <7%; 20% 7-7.9%; 18% 8-8.9%; and 5% >9%. Post intervention survey indicated that the program was well-received, with 62.5% of responses reporting lifestyle changes and 36.3% seeking further advice from their local healthcare providers. CONCLUSION: The study demonstrates a significant prevalence of pre-diabetes and diabetes in the community, similar to findings from larger-scale hospital and general practice studies. Point-of-care testing combined with personalized education effectively motivated participants toward healthier lifestyle choices and medical consultations. The paper discusses the scalability of this approach for broader population.

Point-of-care Testing HbA1c screening for type 2 diabetes in urban and rural areas of China: a cost-effectiveness analysis.

Background: Point-of-care Testing (POCT) glycosylated hemoglobin (HbA1c) is a convenient, cheap, effective and accessible screening method for type 2 diabetes in rural areas and community settings that is widely used in the European region and Japan, but not yet widespread in China. The study is the first to evaluate the cost-effectiveness of POCT HbA1c, fasting capillary glucose (FCG), and venous blood HbA1c to screen for type 2 diabetes in urban and rural areas of China, and to identify the best socio-economically beneficial screening strategy. Methods: Based on urban and rural areas in China, economic models for type 2 diabetes screening were constructed from a social perspective. The subjects of this study were adults aged 18-80 years with undiagnosed type 2 diabetes. Three screening strategies were established for venous blood HbA1c, FCG and POCT HbA1c, and cost-effectiveness analysis was performed by Markov models. One-way sensitivity analysis and probabilistic sensitivity analysis were performed on all parameters of the model to verify the stability of the results. Results: Compared with FCG, POCT HbA1c was cost-effective with an incremental cost-utility ratio (ICUR) of $500.06/quality-adjusted life year (QALY) in urban areas and an ICUR of $185.10/QALY in rural areas, within the willingness-to-pay threshold (WTP = $37,653). POCT HbA1c was cost-effective with lower cost and higher utility compared with venous blood HbA1c in both urban and rural areas. In the comparison of venous blood HbA1c and FCG, venous blood HbA1c was cost-effective (ICUR = $20,833/QALY) in urban areas but not in rural areas (ICUR = $41,858/QALY). Sensitivity analyses showed that the results of the study were stable and credible. Conclusions: POCT HbA1c was cost-effective for type 2 diabetes screening in both urban and rural areas of China, which could be considered for future clinical practice in China. Factors such as geographic location, local financial situation and resident compliance needed to be considered when making the choice of venous blood HbA1c or FCG.

Usefulness of point of care ultrasound in older adults: a multicentre study across different geriatric care settings in Spain and the United Kingdom.

BACKGROUND: Point of care ultrasound (POCUS) is an imaging technique performed bedside. To date, few published studies have reported the usefulness of multiorgan POCUS in Geriatrics. The objective of this study was to describe the utility of multiorgan POCUS in the care of older adults admitted to geriatric care settings. METHODOLOGY: Observational retrospective study of patients admitted to geriatric settings in Spain and UK. Multiorgan POCUS was performed when there was a specific clinical suspicion or unexplained torpid clinical course despite physical examination and complementary tests. A geriatrician with a certificate degree in comprehensive ultrasound and long-standing experience in POCUS carried out POCUS. All patients underwent multiorgan POCUS in a cephalo-caudal manner. RESULTS: Out of 368 patients admitted to geriatric units, 29% met the inclusion criteria. Average age was 85.9 years (SD ± 6.1). POCUS identified 235 clinically significant findings (2.2 per patient). Findings were classified as 37.9% confirmed diagnosis, 16.6% ruled out diagnosis, 14.9% unsuspected relevant diagnoses and 30.6% clinical follow-ups. POCUS findings led to changes in pharmacological and non-pharmacological treatment in 66.3 and 69.2% respectively, resulted in completion or avoidance of invasive procedures in 17.8 and 15.9%, respectively, facilitating early referrals to other specialities in 14.9% and avoiding transfers in 25.2% of patients. CONCLUSION: Multiorgan POCUS is a tool that aids in the assessment and treatment of patients receiving care in geriatrics units. These results show the usefulness of POCUS in the management of older adults and suggest its inclusion in any curriculum of Geriatric Medicine speciality training.

An overview of influenza A virus detection methods: from state-of-the-art of laboratories to point-of-care strategies.

Influenza A virus (IAV), a common respiratory infectious pathogen, poses a significant risk to personal health and public health safety due to rapid mutation and wide host range. To better prevent and treat IAV, comprehensive measures are needed for early and rapid screening and detection of IAV. Although traditional laboratory-based techniques are accurate, they are often time-consuming and not always feasible in emergency or resource-limited areas. In contrast, emerging point-of-care strategies provide faster results but may compromise sensitivity and specificity. Here, this review critically evaluates various detection methods for IAV from established laboratory-based procedures to innovative rapid diagnosis. By analyzing the recent research progress, we aim to address significant gaps in understanding the effectiveness, practicality, and applicability of these methods in different scenarios, which could provide information for healthcare strategies, guide public health response measures, and ultimately strengthen patient care in the face of the ongoing threat of IAV. Through a detailed comparison of diagnostic models, this review can provide a reliable reference for rapid, accurate and efficient detection of IAV, and to contribute to the diagnosis, treatment, prevention, and control of IAV.

Sample preparation and detection methods in point-of-care devices towards future at-home testing.

Timely and accurate diagnosis is critical for effective healthcare, yet nearly half the global population lacks access to basic diagnostics. Point-of-care (POC) testing offers partial solutions by enabling low-cost, rapid diagnosis at the patient's location. At-home POC devices have the potential to advance preventive care and early disease detection. Nevertheless, effective sample preparation and detection methods are essential for accurate results. This review surveys recent advances in sample preparation and detection methods at POC. The goal is to provide an in-depth understanding of how these technologies can enhance at-home POC devices. Lateral flow assays, nucleic acid tests, and virus detection methods are at the forefront of POC diagnostic technology, offering rapid and sensitive tools for identifying and measuring pathogens, biomarkers, and viral infections. By illuminating cutting-edge research on assay development for POC diagnostics, this review aims to accelerate progress towards widely available, user-friendly, at-home health monitoring tools that empower individuals in personalized healthcare in the future.