Smartphone-Enabled Point-of-Care Testing for Prehospital Stroke Diagnosis.

Objectives: The objective of this study was to evaluate the feasibility of point-of-care testing (POCT) devices for N-terminal pro-B-type natriuretic peptide (NT-proBNP) measurement in prehospital settings, with the aim of improving the speed and accuracy of stroke diagnosis, thereby facilitating quicker and more effective patient care.

Methods: Prehospital blood samples were collected from suspected stroke patients, and NT-proBNP levels were measured using a POCT device in ambulances and hospitals. Results from the NT-proBNP POCT and smartphone images were analyzed.

Crucial role of biosensors in the detection of helminth biomarkers in public health programmes.

Helminthiases are highly prevalent but neglected infections that affect more than 1·5 billion people worldwide. Considering the worldwide prevalence of helminthiases, WHO has declared them a public health concern since 2001, necessitating rigorous control and elimination efforts. However, only a few reliable point-of-care diagnostic tests are available for assessing the effectiveness of public health interventions targeting helminthiases, thus increasing the risk of suboptimal outcomes, misallocation of resources, and emergence of drug-resistant helminths.

Not all severe malaria cases are severe: Is it time to redefine severity criteria for malaria in non-endemic regions?

Background: The current definition of severe malaria in non-endemic areas follows WHO criteria, which mainly target children in malaria-endemic areas, potentially misclassifying cases in non-endemic regions. We assessed the performance of a modified severe malaria classification criteria within our patient cohort.

Methods: A cohort study of patients managed for malaria in a non-endemic setting (2005-2023) was analyzed.

Harnessing Bioluminescent Bacteria to Develop an Enzymatic-free Enzyme-linked immunosorbent assay for the Detection of Clinically Relevant Biomarkers.

Enzyme-linked immunosorbent assay (ELISA) is the gold standard technique for measuring protein biomarkers due to its high sensitivity, specificity, and throughput. Despite its success, continuous advancements in ELISA and immunoassay formats are crucial to meet evolving global challenges and to address new analytical needs in diverse applications. To expand the capabilities and applications of immunoassays, we introduce a novel ELISA-like assay that we call Bioluminescent-bacteria-linked immunosorbent assay (BBLISA).

One-Step Laser Nanostructuration of Reduced Graphene Oxide Films Embedding Metal Nanoparticles for Sensing Applications.

The combination of two-dimensional materials and metal nanoparticles (MNPs) allows the fabrication of novel nanocomposites with unique physical/chemical properties exploitable in high-performance smart devices and biosensing strategies. Current methods to obtain graphene-based films decorated with noble MNPs are cumbersome, poorly reproducible, and difficult to scale up. Herein, we propose a straightforward, versatile, surfactant-free, and single-step technique to produce reduced graphene oxide (rGO) conductive films integrating "naked" noble MNPs.

Conformational-switch biosensors as novel tools to support continuous, real-time molecular monitoring in lab-on-a-chip devices.

Recent years have seen continued expansion of the functionality of lab on a chip (LOC) devices. Indeed LOCs now provide scientists and developers with useful and versatile platforms across a myriad of chemical and biological applications. The field still fails, however, to integrate an often important element of bench-top analytics: real-time molecular measurements that can be used to "guide" a chemical response.

The sequestration mechanism as a generalizable approach to improve the sensitivity of biosensors and bioassays.

Biosensors and bioassays, both of which employ proteins and nucleic acids to detect specific molecular targets, have seen significant applications in both biomedical research and clinical practice. This success is largely due to the extraordinary versatility, affinity, and specificity of biomolecular recognition. Nevertheless, these receptors suffer from an inherent limitation: single, saturable binding sites exhibit a hyperbolic relationship (the "Langmuir isotherm") between target concentration and receptor occupancy, which in turn limits the sensitivity of these technologies to small variations in target concentration.

Toward Next Generation Lateral Flow Assays: Integration of Nanomaterials.

Lateral flow assays (LFAs) are currently the most used point-of-care sensors for both diagnostic (e.g., pregnancy test, COVID-19 monitoring) and environmental (e.

Selection and characterisation of bioreceptors to develop nanoparticle-based lateral-flow immunoassays in the context of the SARS-CoV-2 outbreak.

This manuscript aims at raising the attention of the scientific community to the need for better characterised bioreceptors for fast development of point-of-care diagnostic devices able to support mass frequency testing. Particularly, we present the difficulties encountered in finding suitable antibodies for the development of a lateral flow assay for detecting the nucleoprotein of SARS-CoV-2.

Continuous monitoring of molecular biomarkers in microfluidic devices.

The ability to monitor molecular targets is crucial in fields ranging from healthcare to industrial processing to environmental protection. Devices employing biomolecules to achieve this goal are called biosensors. Over the last half century researchers have developed dozens of different biosensor approaches.

Low-Cost, User-Friendly, All-Integrated Smartphone-Based Microplate Reader for Optical-Based Biological and Chemical Analyses.

The quantitative detection of different molecular targets is of utmost importance for a variety of human activities, ranging from healthcare to environmental studies. Bioanalytical methods have been developed to solve this and to achieve the quantification of multiple targets from small volume samples. Generally, they can be divided into two different classes: point of care (PoC) and laboratory-based approaches.

A plug, print & play inkjet printing and impedance-based biosensing technology operating through a smartphone for clinical diagnostics.

Simplicity is one of the key feature for the spread of any successful technological product. Here, a method for rapid and low-cost fabrication of electrochemical biosensors is presented. This "plug, print & play" method involves inkjet-printing even in an office-like environment, without the need of highly specialized expertise or equipment, guaranteeing an ultra-fast idea to (scaled) prototype production time.

Nanodiagnostics to Face SARS-CoV-2 and Future Pandemics: From an Idea to the Market and Beyond.

The COVID-19 pandemic made clear how our society requires quickly available tools to address emerging healthcare issues. Diagnostic assays and devices are used every day to screen for COVID-19 positive patients, with the aim to decide the appropriate treatment and containment measures. In this context, we would have expected to see the use of the most recent diagnostic technologies worldwide, including the advanced ones such as nano-biosensors capable to provide faster, more sensitive, cheaper, and high-throughput results than the standard polymerase chain reaction and lateral flow assays.

Rapid and Efficient Detection of the SARS-CoV-2 Spike Protein Using an Electrochemical Aptamer-Based Sensor.

The availability of sensors able to rapidly detect SARS-CoV-2 directly in biological fluids in a single step would allow performing massive diagnostic testing to track in real time and contain the spread of COVID-19. Motivated by this, here, we developed an electrochemical aptamer-based (EAB) sensor able to achieve the rapid, reagentless, and quantitative measurement of the SARS-CoV-2 spike (S) protein. First, we demonstrated the ability of the selected aptamer to undergo a binding-induced conformational change in the presence of its target using fluorescence spectroscopy.

Lateral flow device for water fecal pollution assessment: from troubleshooting of its microfluidics using bioluminescence to colorimetric monitoring of generic .

Water is the most important ingredient of life. Water fecal pollution threatens water quality worldwide and has direct detrimental effects on human health and the global economy. Nowadays, assessment of water fecal pollution relies on time-consuming techniques that often require well-trained personnel and highly-equipped laboratories.

The Microbiome Meets Nanotechnology: Opportunities and Challenges in Developing New Diagnostic Devices.

Monitoring of the human microbiome is an emerging area of diagnostics for personalized medicine. Here, the potential of different nanomaterials and nanobiosensing technologies is reviewed for the development of novel diagnostic devices for the detection and measurement of microbiome-related biomarkers. Moreover, the current and future landscape of microbiome-based diagnostics is defined by exploring the advantages and disadvantages of current nanotechnology-based approaches, especially in the context of developing point-of-care (PoC) devices that would meet the international guidelines known as REASSURED (Real-time connectivity; Ease of specimen collection; Affordability; Sensitivity; Specificity; User-friendliness; Rapid & robust operation; Equipment-free; and Deliverability).

Paper-Based Electrophoretic Bioassay: Biosensing in Whole Blood Operating via Smartphone.

Point-of-care (PoC) tests are practical and effective diagnostic solutions for major clinical problems, ranging from the monitoring of a pandemic to recurrent or simple measurements. Although, in recent years, a great improvement in the analytical performance of such sensors has been observed, there is still a major issue that has not been properly solved: the ability to perform adequate sample treatments. The main reason is that normally sample treatments require complicated or long procedures not adequate for deployment at the PoC.

Tutorial: design and fabrication of nanoparticle-based lateral-flow immunoassays.

Lateral-flow assays (LFAs) are quick, simple and cheap assays to analyze various samples at the point of care or in the field, making them one of the most widespread biosensors currently available. They have been successfully employed for the detection of a myriad of different targets (ranging from atoms up to whole cells) in all type of samples (including water, blood, foodstuff and environmental samples). Their operation relies on the capillary flow of the sample throughout a series of sequential pads, each with different functionalities aiming to generate a signal to indicate the absence/presence (and, in some cases, the concentration) of the analyte of interest.

Lateral flow assay modified with time-delay wax barriers as a sensitivity and signal enhancement strategy.

The ease of use, low cost and quick operation of lateral flow assays (LFA) have made them some of the most common point of care biosensors in a variety of fields. However, their generally low sensitivity has limited their use for more challenging applications, where the detection of low analytic concentrations is required. Here we propose the use of soluble wax barriers to selectively and temporarily accumulate the target and label nanoparticles on top of the test line (TL).

Real-Time Monitoring of a Protein Biomarker.

The ability to monitor protein biomarkers continuously and in real-time would significantly advance the precision of medicine. Current protein-detection techniques, however, including ELISA and lateral flow assays, provide only time-delayed, single-time-point measurements, limiting their ability to guide prompt responses to rapidly evolving, life-threatening conditions. In response, here we present an electrochemical aptamer-based sensor (EAB) that supports high-frequency, real-time biomarker measurements.

E-DNA scaffold sensors and the reagentless, single-step, measurement of HIV-diagnostic antibodies in human serum.

The multiplexed, point-of-care measurement of specific antibodies could improve the speed with which diseases are diagnosed and their treatment initiated. To this end, we are developing E-DNA scaffold sensors, which consist of a rigid, nucleic acid "scaffold" attached on one end to an electrode and presenting both a redox reporter and an epitope on the other. In the absence of antibody, the reporter efficiently transfers electrons when interrogated electrochemically.

Experimental Comparison in Sensing Breast Cancer Mutations by Signal ON and Signal OFF Paper-Based Electroanalytical Strips.

The development of paper-based electroanalytical strips as powerful diagnostic tools has gained a lot of attention within the sensor community. In particular, the detection of nucleic acids in complex matrices represents a trending topic, especially when focused toward the development of emerging technologies, such as liquid biopsy. DNA-based biosensors have been largely applied in this direction, and currently, there are two main approaches based on target/probe hybridization reported in the literature, namely Signal ON and Signal OFF.

Calibration-Free Measurement of Phenylalanine Levels in the Blood Using an Electrochemical Aptamer-Based Sensor Suitable for Point-of-Care Applications.

By analogy to the revolution the "home glucose monitor" created in the treatment of diabetes, the availability of a modular, "platform" technology able to measure nearly any metabolite, biomarker, or drug "at-home" in unprocessed, finger-prick volumes of whole blood could revolutionize the monitoring and treatment of disease. Thus motivated, we have adapted here the electrochemical aptamer-based sensing platform to the problem of rapidly and conveniently measuring the level of phenylalanine in the blood, an ability that would aid the monitoring and management of phenylketonuria (PKU). To achieve this, we exploited a previously reported DNA aptamer that recognizes phenylalanine in complex with a rhodium-based "receptor" that improves affinity.

Smart Chip for Visual Detection of Bacteria Using the Electrochromic Properties of Polyaniline.

Finding fast and reliable ways to detect pathogenic bacteria is crucial for addressing serious public health issues in clinical, environmental, and food settings. Here, we present a novel assay based on the conversion of an electrochemical signal into a more convenient optical readout for the visual detection of . Electropolymerizing polyaniline (PANI) on an indium tin oxide screen-printed electrode (ITO SPE), we achieved not only the desired electrochromic behavior but also a convenient way to modify the electrode surface with antibodies (taking advantage of the many amine groups of PANI).

Open Source Software for the Real-Time Control, Processing, and Visualization of High-Volume Electrochemical Data.

Electrochemical sensors are major players in the race for improved molecular diagnostics due to their convenience, temporal resolution, manufacturing scalability, and their ability to support real-time measurements. This is evident in the ever-increasing number of health-related electrochemical sensing platforms, ranging from single-measurement point-of-care devices to wearable devices supporting immediate and continuous monitoring. In support of the need for such systems to rapidly process large data volumes, we describe here an open-source, easily customizable, multiplatform compatible program for the real-time control, processing, and visualization of electrochemical data.