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One of the main challenges to be faced in deep space missions is to protect the health and ensure the maximum efficiency of the crew by preparing methods of prevention and in situ diagnosis. Indeed, the hostile environment causes important health problems, ranging from muscle atrophy, osteopenia, and immunological and metabolic alterations due to microgravity, to an increased risk of cancer caused by exposure to radiation. It is, therefore, necessary to provide new methods for the real-time measurement of biomarkers suitable for deepening our knowledge of the effects of space flight on the balance of the immune system and for allowing the monitoring of the astronaut's health during long-term missions. APHRODITE will enable human space exploration because it fills this void that affects both missions in LEO and future missions to the Moon and Mars. Its scientific objectives are the design, production, testing, and in-orbit demonstration of a compact, reusable, and reconfigurable system for performing the real-time analysis of oral fluid samples in manned space missions. In the frame of this project, a crew member onboard the ISS will employ APHRODITE to measure the selected target analytes, cortisol, and dehydroepiandrosterone sulfate (DHEA-S), in oral fluid, in four (plus one additional desired session) separate experiment sessions. The paper addresses the design of the main subsystems of the analytical device and the preliminary results obtained during the first implementations of the device subsystems and testing measurements on Earth. In particular, the system design and the experiment data output of the lab-on-chip photosensors and of the front-end readout electronics are reported in detail along with preliminary chemical tests for the duplex competitive CL-immunoassay for the simultaneous detection of cortisol and DHEA-S. Different applications also on Earth are envisaged for the APHRODITE device, as it will be suitable for point-of-care testing applications (e.g., emergency medicine, bioterrorism, diagnostics in developing countries, etc.). [ABSTRACT FROM AUTHOR]

Wearable biosensors are attracting great interest thanks to their high potential for providing clinical-diagnostic information in real time, exploiting non-invasive sampling of biofluids. In this context, sweat has been demonstrated to contain physiologically relevant biomarkers, even if it has not been exhaustively exploited till now. This biofluid has started to gain attention thanks to the applications offered by wearable biosensors, as it is easily collectable and can be used for continuous monitoring of some parameters. Several studies have reported electrochemical and optical biosensing strategies integrated with flexible, biocompatible, and innovative materials as platforms for biospecific recognition reactions. Furthermore, sampling systems as well as the transport of fluids by microfluidics have been implemented into portable and compact biosensors to improve the wearability of the overall analytical device. In this review, we report and discuss recent pioneering works about the development of sweat sensing technologies, focusing on opportunities and open issues that can be decisive for their applications in routine-personalized healthcare practices. [ABSTRACT FROM AUTHOR]

Analytical chemistry applied to medical and diagnostic analysis has recently focused on the development of cost-effective biosensors able to monitor the health status or to assess the level of specific biomarkers that can be indicative of several diseases. The improvement of technologies relating to the possibility of the non-invasive sampling of biological fluids, as well as sensors for the detection of analytical signals and the computational capabilities of the systems routinely employed in everyday life (e.g., smartphones, computers, etc.), makes the complete integration of self-standing analytical devices more accessible. This review aims to discuss the biosensors that have been proposed in the last five years focusing on two principal detecting approaches, optical and electrochemical, which have been employed for quantifying different kinds of target analytes reaching detection limits below the clinical sample levels required. These detection principles applied to point-of-care (POC) devices have been extensively reported in literature, and even the limited examples found on the market are based on these strategies. This work will show the latest innovations considering the integration of optical and electrochemical detection with the most commonly reported analytical platforms for POC applications such as paper-based or wearable and implantable devices. [ABSTRACT FROM AUTHOR]

Chemiluminescence is widely used for hydrogen peroxide detection, mainly exploiting the highly sensitive peroxidase-luminol-H2O2 system. Hydrogen peroxide plays an important role in several physiological and pathological processes and is produced by oxidases, thus providing a straightforward way to quantify these enzymes and their substrates. Recently, biomolecular self-assembled materials obtained by guanosine and its derivatives and displaying peroxidase enzyme-like catalytic activity have received great interest for hydrogen peroxide biosensing. These soft materials are highly biocompatible and can incorporate foreign substances while preserving a benign environment for biosensing events. In this work, a self-assembled guanosine-derived hydrogel containing a chemiluminescent reagent (luminol) and a catalytic cofactor (hemin) was used as a H2O2-responsive material displaying peroxidase-like activity. Once loaded with glucose oxidase, the hydrogel provided increased enzyme stability and catalytic activity even in alkaline and oxidizing conditions. By exploiting 3D printing technology, a smartphone-based portable chemiluminescence biosensor for glucose was developed. The biosensor allowed the accurate measurement of glucose in serum, including both hypo- and hyperglycemic samples, with a limit of detection of 120 µmol L−1. This approach could be applied for other oxidases, thus enabling the development of bioassays to quantify biomarkers of clinical interest at the point of care. [ABSTRACT FROM AUTHOR]

Food allergies are adverse health effects that arise from specific immune responses, occurring upon exposure to given foods, even if present in traces. Egg allergy is one of the most common food allergies, mainly caused by egg white proteins, with ovalbumin being the most abundant. As allergens can also be present in foodstuff due to unintended contamination, there is a need for analytical tools that are able to rapidly detect allergens in food products at the point-of-use. Herein, we report an origami paper-based device for detecting ovalbumin in food samples, based on a competitive immunoassay with chemiluminescence detection. In this biosensor, magnetic microbeads have been employed for easy and efficient immobilization of ovalbumin on paper. Immobilized ovalbumin competes with the ovalbumin present in the sample for a limited amount of enzyme-labelled anti-ovalbumin antibody. By exploiting the origami approach, a multistep analytical procedure could be performed using reagents preloaded on paper layers, thus providing a ready-to-use immunosensing platform. The assay provided a limit of detection (LOD) of about 1 ng mL−1 for ovalbumin and, when tested on ovalbumin-spiked food matrices (chocolate chip cookies), demonstrated good assay specificity and accuracy, as compared with a commercial immunoassay kit. [ABSTRACT FROM AUTHOR]

Recent advancements in synthetic biology, organic chemistry, and computational models have allowed the application of bioluminescence in several fields, ranging from well established methods for detecting microbial contamination to in vivo imaging to track cancer and stem cells, from cell‐based assays to optogenetics. Moreover, thanks to recent technological progress in miniaturized and sensitive light detectors, such as photodiodes and imaging sensors, it is possible to implement laboratory‐based assays, such as cell‐based and enzymatic assays, into portable analytical devices for point‐of‐care and on‐site applications. This review highlights some recent advances in the development of whole‐cell and cell‐free bioluminescence biosensors with a glance on current challenges and different strategies that have been used to turn bioassays into biosensors with the required analytical performance. Critical issues and unsolved technical problems are also highlighted, to give the reader a taste of this fascinating and challenging field. [ABSTRACT FROM AUTHOR]

Abstract: The point‐of‐care testing concept has been exploited to design and develop portable and cheap bioanalytical systems that can be used on‐site by conservators. These systems employ lateral flow immunoassays to simultaneously detect two proteins (ovalbumin and collagen) in artworks. For an in‐depth study on the application of these portable biosensors, both chemiluminescent and colorimetric detections were developed and compared in terms of sensitivity and feasibility. The chemiluminescent system displayed the best analytical performance (that is, two orders of magnitude lower limits of detection than the colorimetric system). To simplify its use, a disposable cartridge was designed ad hoc for this specific application. These results highlight the enormous potential of these inexpensive, easy‐to‐use, and minimally invasive diagnostic tools for conservators in the cultural heritage field. [ABSTRACT FROM AUTHOR]

Increasingly, smartphones are used as portable personal computers, revolutionizing communication styles and entire lifestyles. Using 3D-printing technology we have made a disposable minicartridge that can be easily prototyped to turn any kind of smartphone or tablet into a portable luminometer to detect chemiluminescence derived from enzyme-coupled reactions. As proof-of-principle, lactate oxidase was coupled with horseradish peroxidase for lactate determination in oral fluid and sweat. Lactate can be quantified in less than five minutes with detection limits of 0.5 mmol L−1 (corresponding to 4.5 mg dL−1) and 0.1 mmol L−1 (corresponding to 0.9 mg dL−1) in oral fluid and sweat, respectively. A smartphone-based device shows adequate analytical performance to offer a cost-effective alternative for non-invasive lactate measurement. It could be used to evaluate lactate variation in relation to the anaerobic threshold in endurance sport and for monitoring lactic acidosis in critical-care patients. [ABSTRACT FROM AUTHOR]

Highlights: [•] Lab-on-chip devices are at the forefront of development of new analytical platforms. [•] Chemical luminescence include chemi-, bio-, and electrochemiluminescence. [•] Chemical luminescence detection techniques offer superior performance in lab-on-chip. [•] We report advances from 2009 to date in chemical luminescence-based lab-on-chip. [ABSTRACT FROM AUTHOR]

We used a luminescence-based biosensor to determine mercury in urine samples of subjects with or without dental amalgam restorations. The system utilizes Escherichia coli as a host organism and firefly luciferase luc gene as a reporter under the control of the mercury-inducible promoter from the mer operon from transposon Tn21. The presence of mercury induces the specific gene sequence with consequent synthesis of the luciferase enzyme, and luciferin/luciferase-mediated light output occurs. The method showed a linear relationship between the light signal intensity and the Hg[SUP2+] concentration in the range of 1.67 × 10[SUP-13]_ 1.67 × 10[SUP-7] M with a detection limit of 1.67 × 10[SUP[-13] M, corresponding to 4.0 × 10[SUP-8] mol/tube. The system proved precise, accurate, and highly selective for mercury and methylmercury, with no light emission induced by other heavy metals; the matrix effect caused by urine components was minimal. The analysis of urine specimens showed that urinary mercury levels in subjects with amalgam fillings were slightly significantly higher than those in subjects without amalgam fillings (p < 0.1) and the statistically significant difference improved when creatinine-normalized values were considered (p < 0.05). In summary, from the analytical point of view this luminescent microbial biosensor represents an easy, rapid, and sensitive tool to analyse Hg[SUP2+] in biological and environmental samples. Along with the possibility of using 384-well microtitre plates requiring very low reagent volumes, these characterisitcs make the system suitable for the high-throughput screening of Hg[SUP2+] on large numbers of specimens. This method could help better clarify the relationship between dental amalgam and urinary mercury excretion by permitting large-scale analysis of many selected groups of subjects, with strict control of all the relevant parameters affecting Hg[SUP2+] concentration in urine, such as diet and... [ABSTRACT FROM AUTHOR]

Since the introduction of paper-based analytical devices as potential diagnostic platforms a few decades ago, huge efforts have been made in this field to develop systems suitable for meeting the requirements for the point-of-care (POC) approach. Considerable progress has been achieved in the adaptation of existing analysis methods to a paper-based format, especially considering the chemiluminescent (CL)-immunoassays-based techniques. The implementation of biospecific assays with CL detection and paper-based technology represents an ideal solution for the development of portable analytical devices for on-site applications, since the peculiarities of these features create a unique combination for fitting the POC purposes. Despite this, the scientific production is not paralleled by the diffusion of such devices into everyday life. This review aims to highlight the open issues that are responsible for this discrepancy and to find the aspects that require a focused and targeted research to make these methods really applicable in routine analysis. [ABSTRACT FROM AUTHOR]

Abstract During space missions, real-time monitoring of astronauts' health status is of crucial importance and therefore there is a strong demand for simple analytical devices that astronauts can use to perform clinical chemistry analyses directly onboard. As part of the "IN SITU Bioanalysis" project, we designed a biosensor for analysing salivary levels of cortisol in astronauts, a marker of chronic stress. The biosensor is based on the Lateral Flow Immunoassay (LFIA) approach coupled with chemiluminescence (CL) detection and comprises a 3D-printed plastic cartridge containing a sealed fluidic element with the LFIA strip, in which the flow of sample and reagents is activated by pressing buttons on the cartridge and sustained by exploiting capillary forces. For measurement, the photon emission is imaged employing a CL reader based on an ultrasensitive cooled charge-coupled device (CCD) camera. The payload was designed to operate in microgravity and to withstand mechanical stress, such as take-off vibrations, and onboard depressurization events, while the microfluidics was developed considering alterations of physical phenomena occurring in microgravity, such as bubble formation, surface wettability and liquid evaporation. The biosensor, which was successfully used by the Italian astronaut Paolo Nespoli during the VITA mission (July-December 2017), demonstrated the feasibility of performing sensitive LFIA analysis of salivary cortisol down to 0.4 ng/mL directly onboard the International Space Station. It could be easily adapted for the analysis of other clinical biomarkers, thus enabling the early diagnosis of diseases and the timely activation of appropriate countermeasures. Graphical abstract fx1 Highlights • A biosensor based on chemiluminescent Lateral Flow Immunoassay was developed. • The biosensor allowed to quantify cortisol in oral fluid sample. • The biosensor was designed to be insensitive to microgravity conditions. • The biosensor was used onboard the ISS for monitoring health status of crew members. • The biosensor was used by the Italian astronaut Paolo Nespoli (VITA mission, 2017). [ABSTRACT FROM AUTHOR]

Long-duration space missions pose important health concerns for astronauts, especially regarding the adverse effects of microgravity and exposure to high-energy cosmic rays. The long-term maintenance of crew health and performance mainly relies on prevention, early diagnoses, condition management, and medical interventions in situ. In-flight biosensor diagnostic devices and medical procedures must use few resources and operate in a microgravity environment, which complicates the collection and management of biological samples. Moreover, the biosensors must be certified for in-flight operation according to strict design and safety regulations. Herein, we report on the state of the art and recent advances in biosensing diagnostic instrumentation for monitoring astronauts’ health during long-duration space missions, including portable and wearable biosensors. We discuss perspectives on new-format biosensors in autonomous space clinics. We also describe our own work in developing biosensing devices for non-invasively diagnosing space-related diseases, and how they are used in long-duration missions. Finally, we discuss the benefits of space exploration for Earth-based medicine. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) printed electrochemical devices are increasingly used in point-of-need and point-of-care testing. They show several advantages such as simple fabrication, low cost, fast response, and excellent selectivity and sensitivity in small sample volumes. However, there are only a few examples of analytical devices combining 3D-printed electrodes with electrochemiluminescence (ECL) detection, an electrochemical detection principle widely employed in clinical chemistry analysis. Herein, a portable, 3D-printed miniaturized ECL biosensor for glucose detection has been developed, based on the luminol/H 2 O 2 ECL system and employing a two-electrode configuration with carbon black-doped polylactic acid (PLA) electrodes. The ECL emission is obtained by means of a 1.5V AA alkaline battery and detected using a smartphone camera, thus providing easy portability of the analytical platform. The ECL system was successfully applied for sensing H 2 O 2 and, upon coupling the luminol/H 2 O 2 system with the enzyme glucose oxidase, for glucose detection. The incorporation of luminol and glucose oxidase in an agarose hydrogel matrix allowed to produce ECL devices preloaded with the reagents required for the assay, so that the analysis only required sample addition. The ECL biosensor showed an excellent ability to detect glucose up to 5 mmol L−1, with a limit of detection of 60 μmol L−1. The biosensor was also used to analyse real samples (i.e., glucose saline solutions and artificial serum samples) with satisfactory results, thus suggesting its suitability for point-of-care analysis. Coupling with other oxidases could further extend the applicability of this analytical platform. • A 3D-printed electrochemiluminescence (ECL) biosensor for glucose was developed. • The 3D-printed electrochemical cell was made in conductive polylactic acid polymer. • The biosensor coupled the glucose oxidase enzyme with the luminol-H 2 O 2 ECL system. • A point-of-care analytical platform using a smartphone as ECL detector was developed. • The biosensor accurately detected glucose in pharmaceutical and biological samples. [ABSTRACT FROM AUTHOR]

Abstract: Simple, rapid and highly sensitive assays, possibly allowing on-site analysis, are required in the security and forensic fields or to obtain early signs of environmental pollution. Several bioanalytical methods and biosensors based on portable devices have been developed for this purpose. Among them, Lateral Flow ImmunoAssays (LFIAs) offer the advantages of rapidity and ease of use and, thanks to the high specificity of antigen–antibody binding, allow greatly simplifying and reducing sample pre-analytical treatments. However, LFIAs usually employ colloidal gold or latex beads as labels and they rely on the formation of colored bands visible by the naked eye. With this assay format, only qualitative or semi-quantitative information can be obtained and low sensitivity is achieved. Recently, the use of enzyme-catalyzed chemiluminescence detection in LFIA has been proposed to overcome these problems. In this work, we describe the development of a quantitative CL-LFIA assay for the detection of 2,4,6-trinitrotoluene (TNT) in real samples. Thanks to the use of a portable imaging device for CL signal measurement based on a thermoelectrically cooled CCD camera, the analysis could be performed directly on-field. A limit of detection of 0.2μgmL−1 TNT was obtained, which is five times lower than that obtained with a previously described colloidal gold-based LFIA developed employing the same immunoreagents. The dynamic range of the assay extended up to 5μgmL−1 TNT and recoveries ranging from 97% to 111% were obtained in the analysis of real samples (post blast residues obtained from controlled explosion). [Copyright &y& Elsevier]

Exposure to mycotoxins, which may contaminate food and feed commodities, represents a serious health risk for consumers. Ochratoxin A (OTA) is one of the most abundant and toxic mycotoxins, thus specific regulations for fixing its maximum admissible levels in foodstuff have been established. Lateral Flow ImmunoAssay (LFIA)-based devices have been proposed as screening tools to avoid OTA contamination along the whole food chain. We report a portable, user-friendly smartphone-based biosensor for the detection and quantification of OTA in wine and instant coffee, which combines the LFIA approach with chemiluminescence (CL) detection. The device employs the smartphone camera as a light detector and uses low-cost, disposable analytical cartridges containing the LFIA strip and all the necessary reagents. The analysis can be carried out at the point of need by non-specialized operators through simple manual operations. The biosensor allows OTA quantitative detection in wine and coffee samples up to 25 μg L−1 and with limits of detection of 0.3 and 0.1 μg L−1, respectively, which are below the European law-fixed limits. These results demonstrate that the developed device can be used for routine monitoring of OTA contamination, enabling rapid and reliable identification of positive samples requiring confirmatory analysis. [Display omitted] • Smartphone-based biosensor developed by chemiluminescence Lateral Flow Immunoassay. • Ochratoxin A quantitative detection below EU law limits in wine and coffee samples. • Ready-to-use self-contained analytical cartridge for rapid on-field application. • The biosensor enables screening for OTA contamination along the whole food chain. [ABSTRACT FROM AUTHOR]