Raman-enhanced sensor based on CRISPR-SERS technology for the rapid and hypersensitive detection of Mycobacterium tuberculosis.

Tuberculosis is a highly infectious disease caused by the bacterium Mycobacterium tuberculosis, and the spread of this agent has caused serious health problems worldwide. The rapid and accurate detection of M. tuberculosis is essential for controlling the spread of infection and for preventing the emergence of multidrug-resistant strains. In this study, the powerful trans-cleavage ability of CRISPR-Cas12a for ssDNA was combined with a surface-enhanced Raman spectroscopy (SERS)-based strategy to establish a CRISPR-SERS sensor for the hypersensitive detection of M. tuberculosis DNA. We observed a linear relationship between the concentration of M. tuberculosis DNA and the output signal over the range of 5 to 100 pM. The equation describing the standard curve was y = 24.10x + 1594, with R2 = 0.9914. The limit of detection was as low as 4.42 pM for genomic DNA, and a plasmid containing an M. tuberculosis-specific sequence was detected at 5 copy/µL. A detection accuracy of 100% was achieved in the analysis of DNA isolated from the sputum of hospitalized patients with tuberculosis. The entire detection process is simple to deploy and only takes 50 min and results in the sensitive and specific detection of M. tuberculosis DNA. This study provides a new method for the detection of tuberculosis. The tool is stable and can be utilized on-site, and it thus broadens the diagnostic application of CRISPR-Cas12a-based sensor technology.

Point-of-Care Testing for Cardiovascular Disease: A Narrative Review.

Cardiovascular disease is a major global public health challenge. Point-of-- care testing (POCT) technologies are crucial for the prevention, early diagnosis, and treatment of cardiovascular conditions. Numerous POCT technologies for cardiovascular disease are currently available, which include but are not limited to conventional methods, paper-based microfluidic technology, microfluidic chip technology, electrochemical detection technology, ultrasonic detection technology, and smartphone-based detection technology. Each method has a broad range of applications and performs differently across various detection scenarios. This article offers a comprehensive analysis of current POCT technologies for cardiovascular disease, assessing their effectiveness, limitations, and future development directions. The aim is to provide insights and theoretical references for innovative research and clinical applications in POCT methods for cardiovascular disease.

Needle-Plug/Piston-Based Modular Mesoscopic Design Paradigm Coupled With Microfluidic Device for Point-of-Care Pooled Testing.

Emerging diagnostic scenarios, such as population surveillance by pooled testing and on-site rapid diagnosis, highlight the importance of advanced microfluidic systems for in vitro diagnostics. However, the widespread adoption of microfluidic technology faces challenges due to the lack of standardized design paradigms, posing difficulties in managing macro-micro fluidic interfaces, reagent storage, and complex macrofluidic operations. This paper introduces a novel modular-based mesoscopic design paradigm, featuring a core "needle-plug/piston" structure with versatile variants for complex fluidic operations. These structures can be easily coupled with various microfluidic platforms to achieve truly self-contained microsystems. Incorporated into a "3D extensible" design architecture, the mesoscopic design meets the demands of function integration, macrofluid manipulations, and flexible throughputs for point-of-care nucleic acid testing. Using this approach, an ultra-sensitive nucleic acid detection system is developed with a limit of detection of ten copies of SARS-CoV-2 per mL. This system efficiently conducts large-scale pooled testing from 50 pharyngeal swabs in a tube with an uncompromised sensitivity, enabling a truly "sample-in-answer-out" microsystem with exceptional performance.

Potential use of Six Sigma metrics in the quality control review of hospital glucose meters.

Background and aim: This study applied Six Sigma metrics to facilitate the quality control (QC) review for hospital glucose meters. Materials and methods: QC data from a period of six months on all hospital glucose meters were extracted from the data management system. Sigma values for each meter at two QC levels were calculated and evaluated each month by combining the imprecision, the absolute bias between the meter mean and all-meter mean, and the standards from ISO 15179:2013. The effectiveness of using Sigma values in identifying meters with possible quality problems for further Levey-Jennings QC chart review was assessed. Results: More than 80 % of the meter's Sigma values within the six months were greater than 4 at either QC level. At the high QC level, twice as many Sigma values were below 4 than the low QC level. Including Sigma values 4, 3.5 or 3 in the criteria for the QC review reduced the number of chart review to 32.8 %, 11.2 % or 3.5 %, respectively. Conclusions: The majority of the glucose meters examined in this study demonstrated optimal Sigma values. The Sigma metrics-based approach could be a valuable tool to guide an effective QC review of glucose meters for quality improvement.

Comparison of the Quantra QPlus and ROTEM Goal-Directed Transfusion Protocols in Cardiothoracic Surgery Patients: A Prospective Observational Study.

OBJECTIVES: To compare the designed treatment protocols for the Quantra QPlus and rotational thromboelastometry (ROTEM) with regard to transfusion advice. DESIGN: Prospective observational study. SETTING: Maastricht University Medical Center, The Netherlands. PARTICIPANTS: Adults with elective cardiopulmonary bypass surgery with a ROTEM test. INTERVENTIONS: ROTEM tests were performed postoperatively for standard monitoring of coagulation status and clinical decision making. Simultaneously, a concurrent sample was analyzed for the Quantra QPlus. MEASUREMENTS AND MAIN RESULTS: A total of 100 samples were analyzed using both the ROTEM and Quantra QPlus. Agreement between the transfusion advice for the ROTEM and Quantra QPlus protocols were compared using Cohen κ values for i.a. fibrinogen, platelet concentrates, and fresh frozen plasma (FFP). The agreement between ROTEM and Quantra QPlus was poor for overall transfusion (0.174) and fibrinogen transfusion (0.300). The agreement of cutoff values for fibrinogen clot stiffness for the Quantra QPlus and EXTEM A10 for the ROTEM was poor (0.160). The fibrinogen clot stiffness and FIBTEM A10 had a moderate agreement (0.731). A Cohen κ could not be calculated for the agreement of protamine, thrombocytes, FFP or cutoff values for these transfusions since frequencies included zero in these cases. The Quantra QPlus transfusion protocol advises transfusion in many non-bleeders, adjustments appear to be necessary. In a small group of cases in which clinically relevant blood loss was observed, the Quantra QPlus advised administration of transfusion products, whereas the ROTEM tests did not. CONCLUSION: ROTEM-guided and Quantra-guided transfusion did not correspond in this patient group, and agreement was moderate at best. Specificity and sensitivity for transfusion within protocols were heterogeneous between the methods. More clinical research in high-bleeding risk populations is needed to determine the clinical impact of the different protocols.

Diagnostic accuracy of Cardiochek® PA point-of-care testing (POCT) analyser with a 3-in-1 lipid panel for epidemiological surveys.

BACKGROUND: Point-of-care testing (POCT) is commonly used in epidemiological surveys due to its various advantages, such as portability and immediate test results. The CardioChek® PA analyser 3-in-1 lipid panel measures total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL) cholesterol and low-density lipoprotein (LDL) cholesterol. This study tested the reliability and diagnostic accuracy of the CardioChek® PA analyser using a 3-in-1 lipid panel. METHODS: A cross-sectional study design with quota sampling was used. A total of 203 respondents aged 18 years and above from a research centre in the Ministry of Health, Malaysia, were recruited. Venous blood was sent to the laboratory and tested with Siemens Atellica CH, while a POCT analyser was used for capillary blood measurements. Intraclass coefficient correlation (ICC) analysis was employed to determine the agreement between capillary and venous blood parameters. The diagnostic performance of the evaluated tests was evaluated using STATA version 12. RESULTS: The agreement between capillary and laboratory venous blood was moderate (0.64-0.67) for TC and HDL, good (0.75) for LDL and excellent (0.91) for TG). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were as follows: TC, 57.1%, 94.3%, 92.3% and 64.8%; TG, 76.0%, 100%, 100%, and 96.6%; HDL, 96.2%, 83.2%, 47.2% and 99.3%; and LDL, 81.0%, 100%, 100% and 68.3%, respectively. CONCLUSIONS: The CardioChek® PA analyser showed acceptable diagnostic accuracy for screening high-risk individuals more often in places where laboratories are inaccessible. It could also be used in clinical settings where patients would benefit from swift treatment decisions.

Evaluation of utilization and consequences of CRP point-of-care-testing in primary care practices: qualitative interviews with general practitioners from Germany.

BACKGROUND: The use and advantages of point-of-care tests (POCTs) for C-reactive protein (CRP) in general practice, especially for upper respiratory tract infections (uRTIs), have been studied extensively. However, there is limited knowledge about test indications, prerequisites, and integration of these tests into everyday practice. AIM: This study aims to investigate the attitudes and experiences of general practitioners (GPs) in Germany regarding the use of semi-quantitative CRP-POCTs. The study places special emphasis on implementation in routine care, including testing procedures, feasibility, opportunities and barriers for specific consultation scenarios, as well as test indications and their impact on GP-patient communication. DESIGN & SETTING: Qualitative interview study with 10 GPs (May/2023 to Aug/2023) METHOD: Ten German GPs who participated in an observational study on CRP-POCT use in general practices were interviewed using semi-structured interviews. Audio recordings were transcribed and content analysis was performed. RESULTS: Interviewed GPs stated that CRP-POCTs offer several advantages for various treatment cases. They improve diagnostic confidence and certainty of GPs' therapeutic decisions, and offer a broad spectrum of indications and application scenarios. Additionally, they have a positive impact on GP-patient communication, and their ease of use enables rapid implementation into existing workflows. On the other hand, CRP-POCT increase the time required for test performance and patient consultation. CONCLUSION: Due to the numerous benefits of semi-quantitative CRP-POCTs, interviewed GPs have a favourable attitude towards their regular integration into everyday practice. Implementation barriers include increased time and personnel expenses for testing and inadequate reimbursement by German statutory health insurance.

Performance of point-of-care glucose testing for the diagnosis of gestational diabetes in South Africa.

OBJECTIVE: Lack of accessibility to oral glucose tolerance tests (OGTTs) in South Africa means many pregnant women go without testing for gestational diabetes mellitus (GDM). This study evaluated point-of-care (POC) glucometers against the laboratory-based glucose method in pregnant women. METHODS: This was a cross-sectional study on pregnant women attending the prenatal clinic in Johannesburg who were recommended for the OGTT. OGTTs were conducted as per International Association of Diabetes and Pregnancy Study Groups (IADPSG) guidelines. Women who consented to the study donated both venous and capillary blood for laboratory-based and POC glucose measurements using seven POC glucometers: I-STAT, Xpress, LDX, VivaChek-Ino, Accu-Chek Active, StatStrip, and Codefree. By assessing sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) and comparing Bland-Altman plots, the diagnostic accuracy of each glucose meter was compared with the reference method, the laboratory-based glucose method. RESULTS: Data were analyzed for 1076 pregnant women. Based on OGTT testing, 83 women had GDM (7.7%). Overall, the POC glucometers performed poorly, with sensitivity ranging from 17.6% to 87.18% and specificity ranging between 62.7% and 99.8%. The AUC ranged from 0.59 to 0.79. All POC glucometers showed moderate to poor reliability. Laboratory-based fasting plasma glucose (FPG) surpassed the POC glucometers in sensitivity, specificity, and AUC, with values of 94.0%, 100%, and 0.98, respectively. CONCLUSION: We demonstrated that laboratory-based FPG has the potential to be used as a diagnostic test for GDM and that the POC glucometers cannot replace OGTT laboratory-based measurements.

Amplification-free nucleic acids detection with next-generation CRISPR/dx systems.

CRISPR-based diagnostics (CRISPR/Dx) have revolutionized the field of molecular diagnostics. It enables home self-test, field-deployable, and point-of-care testing (POCT). Despite the great potential of CRISPR/Dx in diagnoses of biologically complex diseases, preamplification of the template often is required for the sensitive detection of low-abundance nucleic acids. Various amplification-free CRISPR/Dx systems were recently developed to enhance signal detection at sufficient sensitivity. Broadly, these amplification-free CRISPR/Dx systems are classified into five groups depending on the signal enhancement strategies employed: CRISPR/Cas12a and/or CRISPR/Cas13a are integrated with: (1) other catalytic enzymes (Cas14a, Csm6, Argonaute, duplex-specific nuclease, nanozyme, or T7 exonuclease), (2) rational-designed oligonucleotides (multivalent aptamer, tetrahedral DNA framework, RNA G-quadruplexes, DNA roller machine, switchable-caged guide RNA, hybrid locked RNA/DNA probe, hybridized cascade probe, or "U" rich stem-loop RNA), (3) nanomaterials (nanophotonic structure, gold nanoparticle, micromotor, or microbeads), (4) electrochemical and piezoelectric plate biosensors (SERS nanoprobes, graphene field-effect transistor, redox probe, or primer exchange reaction), or (5) cutting-edge detection technology platforms (digital bioanalysis, droplet microfluidic, smartphone camera, or single nanoparticle counting). Herein, we critically discuss the advances, pitfalls and future perspectives for these amplification-free CRISPR/Dx systems in nucleic acids detection. The continued refinement of these CRISPR/Dx systems will pave the road for rapid, cost-effective, ultrasensitive, and ultraspecific on-site detection without resorting to target amplification, with the ultimate goal of establishing CRISPR/Dx as the paragon of diagnostics.

An intelligent fluorescence sensing platform based on entropy-driven toehold-mediated strand displacement cycle reaction for point-of-care testing of miRNA.

BACKGROUND: MicroRNA (miRNA) has gradually become an emerging biomarker for early diagnosis and prognosis of various diseases due to its specific gene expression and high stability. With the development of molecular diagnosis and point-of-care testing (POCT) technology, developing simple, fast, sensitive, efficient, and low-cost miRNA sensors is of great significance for clinical applications and emergency rapid diagnosis. At present, entropy-driven toehold mediated chain displacement reaction, as a promising enzyme free isothermal amplification technique, is an important tool for ultra-sensitive biosensing applications. RESULTS: In this study, we used gold nanoparticles (AuNPs) as carriers and quenchers, modified them using self-assembled triple chain composite substrates AuNPs@A@B1/B2, and used dual reporter molecules for cascade cyclic amplification to amplify fluorescence signals, which proposed a fluorescent biosensor based on this reaction and build an intelligent fluorescence sensing platform for rapid detection of miRNA. We designed a highly specific self-programmable sensor using the acute ischemic stroke (AIS) biomarker miRNA-125a-5p as a sample, and achieved sensitive detection of miRNA in the range of 0.01 µM∼10 µ M under optimal conditions. It broke through the traditional detection limitations of weak signals and liberated the fluorescence detection environment. SIGNIFICANCE: In summary, this creative miRNA biosensor combined with POCT has demonstrated extraordinary detection potential, broad application prospects in the early diagnosis and prognosis monitoring of AIS, provides a novel miRNA universal detection strategy for the fields of biological and life sciences.

Commercial Strip-Inspired One-Pot CRISPR-Based Chip for Multiplexed Detection of Respiratory Viruses.

The absence of sensitive, multiplexed, and point-of-care assays poses a critical obstacle in promptly responding to emerging human respiratory virus (HRV) pandemics. Herein, RECOGNIZER (re-building commercial pregnancy strips via large-size nanoflowers), an innovative one-pot CRISPR assay, is presented that employs commercially available strips to identify several types of HRVs. The superiority of the RECOGNIZER assay mainly relies on two aspects: (i) DNA nanoflowers possessing a high surface-to-volume ratio and well-defined surface allow for a considerable probe loading density and minimized non-specific interaction, achieving an impressive signal-to-noise proportion exceeding tenfold at 1 nM target. (ii) The design of the one-pot reaction, multi-channel chip, and custom-made app enables the rapid, sample-to-answer, and multiplexed analysis of four HRVs in 25 min. This assay demonstrates a sensitivity of 5.42 pM for synthetic SARS-CoV-2 RNA and 10 copies µL-1 for SARS-CoV-2 plasmids after pre-amplification. Finally, the proposed approach indicated 100% accuracy in 50 clinical swab samples, demonstrating the robust performance in distinguishing SARS-CoV-2 from other HRVs. The versatility and scalability of RECOGNIZER renders it a user-friendly platform for virus infection monitoring, offering significant potential for improving pandemic response efforts.

Rapid point-of-care testing for hepatitis C - assessment of feasibility, knowledge of participants and outcomes.

Aim: We assessed the feasibility of point-of-care testing to gain insights into participants' knowledge, experience and its effect on hepatitis C management. Background: In New Zealand, only 50% of people infected with hepatitis C (HCV) are currently diagnosed. HCV infection is the most common diagnosis leading to liver transplantation in New Zealand. A point-of-care test can streamline HCV management. Methods: The OraQuick HCV test (mouth swab or finger-prick) was offered to participants aged 45 to 65 and anyone with a risk factor for hepatitis C. Data collected included demographics, risk factors, and participant experience with testing. Results: A total of 218 participants were recruited. The median age was 29 years (IQR 22 to 46). All the tests via the finger-prick method were negative. Fourteen positive mouth-swab tests were negative on ELISA testing. One person was detected to have HCV infection and treated. Knowledge regarding HCV was low. There were no statistically significant differences in knowledge between participants with different education levels, F (4213=0.857, P=0.491 and different ethnicities, F (4,213)0.857, P=0.491. The majority of study participants preferred the point-of-care test. Conclusion: Point-of-care testing for HCV is feasible and preferred. Knowledge regarding HCV was low. This study has also provided valuable insights into the viability and experience of offering point-of-care testing.

Real-world performance of a single-use, analyser-free, molecular point-of-care test for COVID-19 used in the emergency department: Results of a prospective trial (ED-POC).

BACKGROUND: A novel single-use, analyser-free, molecular point-of-care test for SARS-CoV-2 (Veros COVID-19 test, Sherlock Biosciences) could reduce time to results and improve patient care and flow in the emergency department (ED), but its performance in this setting is unknown. METHODS: Adults aged ≥18 years presenting to Southampton General Hospital (UK) with suspected COVID-19 were tested with the Veros COVID-19 test in addition to standard of care near-patient PCR. Measures of diagnostic accuracy were calculated for the Veros COVID-19 test stratified by Ct value. Discrepant results underwent viral culture. FINDINGS: Between Jan 16 and May 2, 2023, 400 patients were enrolled with a median (IQR) age of 60 (34-77) and 141 (35·3%) were SARS-CoV-2 positive by PCR. The Veros test gave valid results on the first test in 384 (96·0%), and sensitivity and specificity were 127/141 (90·1%, 95%CI 83·9-94·5) and 258/259 (99·6%, 95%CI 97·9-100) overall. For those with high or moderate viral load (Ct ≤30), sensitivity was 125/129 (96·9%, 95%CI 92·3-99·2). One (7·1%) of 14 PCR positive/Veros test negative samples was culture positive. Median (IQR) time from sample collection to result was 19 (18-20) mins with the Veros test versus 73 (59-92) mins with PCR (p < 0·0001). INTERPRETATION: The Veros COVID-19 test generated results in near real-time, around 1 h sooner than rapid, near-patient, analyser-based PCR, and accuracy was excellent for samples with moderate and high viral loads. The Veros test represents a step-change in molecular diagnostics for infection and could significantly reduce time to results and improve patient management in EDs and other settings.

Development of a µPAD for the point-of-care testing of serum glutamic oxaloacetic transaminase (SGOT).

A wax-patterned paper analytical device (µPAD) has been developed for point-of-care colourimetric testing of serum glutamic oxaloacetic transaminase (SGOT). The detection method was based on the transamination reaction of aspartate with α-ketoglutarate, leading to the formation of oxaloacetate which reacts with the reagent Fast Blue BB salt and forms a cavern pink colour. The intensity of the cavern pink colour grows as the concentration of SGOT increases. UV-visible spectroscopy was utilized to optimize reaction conditions, and the optimized reagents were dropped onto the wax-patterned paper. The coloured PADs, after the addition of SGOT, have been photographed, and a colour band has been generated to correlate the SGOT concentration visually. The images were used to calculate the intensity values using ImageJ software, which inturn was used to calculate the SGOT concentration. The PADs were also tested with serum samples, and SGOT spiked serum samples. The PAD could detect the SGOT concentration ranging from 5 to 200 U/L. The analysis yielded highly accurate results with less than 6% relative error compared to the clinical sample. This colourimetric test demonstrated exceptional selectivity in the presence of other biomolecules in the blood serum, with a detection limit of 2.77 U/L and a limit of quantification of 9.25 U/L. Additionally, a plasma separation membrane was integrated with the PAD to directly test SGOT from finger-prick blood samples.

Effect of Combination of Point-of-Care C-Reactive Protein Testing and General Practitioner Education and Long-Term Effect of Education on Reducing Antibiotic Prescribing for Children Presenting with Acute Infections in General Practice in Latvia: A Randomized Controlled Intervention Study.

BACKGROUND: Antibiotics are often overprescribed in children in general practice. We investigated whether the availability of C-reactive protein point-of-care testing (CRP POCT) in daily practice and general practitioner (GP) education reduces antibiotic prescribing for children with acute infections and whether GP education has a long-term effect on antibiotic prescribing. METHODS: This was a randomized controlled intervention study with randomization at the GP practice level. Eligible patients were children aged 1 month to 17 years presenting to general practice with an acute infection. INTERVENTIONS: In the first study period, one GP group received combined interventions (CRP POCT was provided for daily use in combination with a live educational session), while the second GP group continued usual care. During the second study period, the GP groups were switched. During this period, the long-term education effect was evaluated in the GP group, which had previously received both interventions: the CRP POCT was no longer available in their practices in accordance with the study protocol, but education could have a lasting effect. PRIMARY OUTCOME: Antibiotic prescribing at index consultation. RESULTS: GP with combined intervention enrolled 1784 patients, GP with usual care enrolled 886 patients, and GP with long-term education effect enrolled 647 patients. Most of the patients had upper (76.8%) and lower (18.8%) respiratory infections. In total, 29.3% of the study patients received antibiotic prescriptions. Adjusted binary logistic regression analysis showed no differences for the primary outcome between GPs with usual care and GPs with combined intervention (aOR 0.89 (0.74-1.07), p = 0.20), but significantly lower antibiotic prescribing was observed for GPs with long-term education in comparison with GPs with usual care (aOR 0.75 (0.59-0.96), p = 0.02); however, after multilevel analyses, any differences in the antibiotic prescription between intervention groups became non-significant. GPs widely used CRP POCT when it was available in practice (for 69.1% of patients in the combined intervention group), but rarely measured CRP in the laboratory in the usual care group (8.8% (n = 78)) or long-term education group (14.8% (n = 98)). The majority of the tested patients had low CRP levels (below 20 mg/L); despite this, up to 35.4% of them received antibiotic prescriptions. CONCLUSIONS: Our results show that the availability of CRP POCT and educational training for GPs together did not reduce antibiotic prescribing, and one-time education did not have a long-term effect on antibiotic prescribing.

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.

An intelligent device with double fluorescent carbon dots based on smartphone for visual and point-of-care testing of Copper(II) in water and food samples.

The excessive presence of Cu2+ could be harmful to human health. Therefore, a ratiometric fluorescence sensor based on multicolor fluorescent carbon dots (CDs) was developed for Cu2+ detection. The blue and yellow carbon dots (B-CDs/Y-CDs) were synthesized by one-step hydrothermal method. After adding Cu2+, it is captured by the amino groups of B-CDs to form complexes, resulting in a strong fluorescence quenching via photoinduced electron transfer (PET). Meanwhile, the amino groups from Y-CDs also binds with Cu2+ that inhibit the internal PET thus enhancing the fluorescence of Y-CDs. The sensor has the merits in rapid, visual, and selective with a low limit of detection (LOD) at 2.29 nM. Furthermore, an intelligent device composed of portable optical detector and smartphone is constructed, which realizes the visual point-of-care testing (POCT) of Cu2+ with a LOD of 7.51 nM. The strategy provides an accessible approach for monitoring heavy metal pollution and food safety.

Innovative approach of nanopore-based metagenomic sequencing for rapid identification of bacterial pathogens in joint fluid: A pilot study.

Analysis of 11 clinical samples of joint fluid in this pilot study demonstrated proof-of-concept for nanopore-based metagenomic sequencing to serve as a complementary real-time diagnostic technique for septic arthritis, with a sensitivity of 75.0 % and specificity of 57.1 %, compared to the gold standard method of bacterial culture.

A Finger-Actuated Sample-Dosing Capillary-Driven Microfluidic Device for Loop-Mediated Isothermal Amplification.

Loop-mediated isothermal amplification (LAMP) has attracted significant attention for rapid and accurate point-of-care diagnostics. However, integrating sample introduction, lysis, amplification, and detection steps into an easy-to-use, disposable system has so far been challenging. This has limited the uptake of the technique in practical applications. In this study, we developed a colourimetric one-step LAMP assay that combines thermolysis and LAMP reaction, to detect the SARS-CoV-2 virus in nasopharyngeal swab samples from COVID-19-infected individuals. The limit of detection was 500 copies per reaction at 65 °C for 25 min in reaction tubes. Additionally, we developed a finger-operated capillary-driven microfluidic device with selective PVA coating. This finger-actuated microfluidic device could self-dose the required sample amount for the LAMP reaction and inhibit sample evaporation. Finally, we integrated the LAMP assay into the microfluidic device by short-term pre-storage of the LAMP master mix. Using this device, nasopharyngeal swab samples from COVID-19-infected individuals showed positive results at a reaction time of 35 min at 65 °C. This integrated device may be adapted to detect other RNA viruses of interest rapidly.

Admission Point-of-Care Testing for the Clinical Care of Children with Cerebral Malaria.

Point-of-care testing (PoCT), an alternative to laboratory-based testing, may be useful in the clinical care of critically ill children in resource-limited settings. We evaluated the clinical utility of PoCT in the care of 193 Malawian children treated for World Health Organization-defined cerebral malaria (CM) between March 2019 and May 2023. We assessed the frequency of abnormal PoCT results and the clinical interventions performed in response to these abnormalities. We determined the association between abnormal PoCT results and patient outcomes. Overall, 52.1% of all PoCT results were abnormal. Of the children with abnormal results, clinical interventions occurred in 16.9%. Interventions most commonly followed abnormal results for PoCT glucose (100.0% of the patients had treatment for hypoglycemia), potassium (32.1%), lactate (22.0%), and creatinine (16.3%). Patients with hypoglycemia, hyperlactatemia, and hypocalcemia had a higher mortality risk than children with normal values. Future studies are needed to determine whether obtaining laboratory values using PoCT and the clinical response to these interventions modify outcomes in critically ill African children with CM.