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Nicotine gum Ailments: Key Exacerbators involving Pulmonary Illnesses?
The article systematically enlightens a clear overview of the clinically adopted techniques for the detection of COVID-19 including oligonucleotide-based molecular detection, Point-of-Care immunodiagnostics, radiographical analysis/sensing system, and newly developed biosensing prototypes having commercial viability. The commercial kits/analytical methods based-sensing strategies have also been tabulated categorically. The critical insights on the developer, commercial brand name, detection methods, technical operational details, detection time, clinical specimen, status, the limit of detection/detection ability have been discussed comprehensively. We believe that this review may provide scientists, clinicians and healthcare manufacturers valuable information regarding the most recent developments/approaches towards COVID-19 diagnosis.The rapidly growing demand for humidity sensing in various applications such as noninvasive epidermal sensing, water status tracking of plants, and environmental monitoring has triggered the development of high-performance humidity sensors. In particular, timely communication with plants to understand their physiological status may facilitate preventing negative influence of environmental stress and enhancing agricultural output. In addition, precise humidity sensing at bio-interface requires the sensor to be both flexible and stable. However, challenges still exist for the realization of efficient and large-scale production of flexible humidity sensors for bio-interface applications. Here, a convenient, effective, and robust method for massive production of flexible and wearable humidity sensor is proposed, using laser direct writing technology to produce laser-induced graphene interdigital electrode (LIG-IDE). Compared to previous methods, this strategy abandons the complicated and costly procedures for traditional IDE preparation. Using graphene oxide (GO) as the humidity-sensitive material, a flexible capacitive-type GO-based humidity sensor with low hysteresis, high sensitivity (3215.25 pF/% RH), and long-term stability (variation less than ± 1%) is obtained. These superior properties enable the sensor with multifunctional applications such as noncontact humidity sensing and human breath monitoring. In addition, this flexible humidity sensor can be directly attached onto the plant leaves for real-time and long-term tracking transpiration from the stomata, without causing any damage to plants, making it a promising candidate for next-generation electronics for intelligent agriculture.Cathodic photoelectrochemical (PEC) bioassay is more resistant to reductive interferents, and development of high-performance photocathode is imperatively required in precise monitoring target in complex matrices. In this work, a plasmonic Au activated amorphous MoSx photocathode (a-MoSx/Au) was fabricated by sequential electrodeposition. Coupled with a sensitization amplification strategy induced by target-aptamer recognition, an ultrasensitive and high-affinitive signal-on cathodic PEC aptasensor for insulin detection was developed. Under optimum conditions, the sensor exhibits a wide linear range (0.1 pg/mL~100 ng/mL) and an ultralow detection limit (28 fg/mL) even lower than most sensors reported so far. Plasmonic Au activation and target-induced sensitization effect are responsible for high-performance PEC aptasensing of insulin at a-MoSx photocathode.As one of the most important proteolytic enzymes, trypsin is useful as a reliable and specific biomarker for the diagnosis of pancreatitis and other pathological conditions. In this paper, a novel signal-on electrochemical biosensor based on the use of electrochemically controlled grafting of polymers as an amplification strategy is described for the ultrasensitive assay of trypsin activity. The carboxyl-group-free peptide, serving as the substrate for the recognition of trypsin, is first immobilized via its N-terminus. The tryptic cleavage of peptide substrate can generate a free carboxyl group at the C-terminus of the truncated peptide, to which through the carboxylate-Zr(IV)-carboxylate linkage the carboxyl-group-containing initiator for atom transfer radical polymerization (ATRP) can be conjugated. The subsequent surface-initiated grafting of polymers (SI-GOP) based on electrochemically controlled ATRP (eATRP), with ferrocenylmethyl methacrylate (FcMMA) as the monomer, can bring a large amount of Fc tags to electrode surface, resulting in the generation of a very high detection signal. The eATRP-based SI-GOP is easy to operate and low-cost as an amplification strategy. Under optimal conditions, the detection limit for trypsin activity can be down to 0.016 mU mL-1 (~2.68 pM or ~0.064 ng mL-1). As the current signal increases with trypsin activity, this trypsin biosensor is less susceptible to false positives due to the signal-on mode. Moreover, it is highly selective and applicable to inhibitor screening and the assay of trypsin activity in the presence of complex biological matrices. Taking together, this electrochemical trypsin biosensor may hold great potential in diagnostic applications.A self-powered aptasensor for prostate specific antigen (PSA) based on a membraneless photoelectrochemical fuel cell (PEFC) with double photoelectrodes was constructed, in which, PSA-binding aptamer was electrostatically immobilized on the KOH-doped g-C3N4 modified TiO2 nanotube arrays (TNA/A-g-C3N4/aptamer), which was used as a photoanode, and Fe3+-doped CuBi2O4 modified indium doped tin oxide (ITO) substrate (ITO/CBFeO) was used as a photocathode. Under visible light irradiation, glucose was photocatalytically oxidized by A-g-C3N4 and generated H2O2 in situ, which was used as the electron acceptor for ITO/CBFeO photocathode, thus producing a high cell output response with a maximum output power of 133.5 μW cm-2 and an open circuit potential of 0.98 V. Due to the specific recognition of PSA by the aptamer and the output power decrease of the PEFC caused by the steric hindrance of the captured PSA on the TNA/A-g-C3N4, the PEFC could be used as a self-powered aptasensor for PSA with a quantitative range of 0.005-50 ng mL-1, a low detection limit of 1.3 pg mL-1 and good selectivity, and has been successfully applied for the analysis of real human serum samples with good precision of the relative standard deviation (RSD) less than 5.6% and good accuracy of the recoveries ranged from 91% to 108%.Electrogenic bacteria or exoelectrogens can transfer electrons to extracellular electron acceptors and thus have a wide range of applications to the ever-emerging fields of bioenergy, bioremediation, and biosensing. Standard state-of-the-art techniques for screening of electrogenic bacteria are inefficient, and often prevent rapid, high-throughput analyses. selleck inhibitor Herein, we created a simple, rapid, and straightforward papertronic 4- and 16-channel sensing platforms that is connected to a visual readout, allowing the naked eye to evaluate and quantify direct bacterial electrogenic capabilities. Our system integrated multiple 2-electrode sensing units into a signal amplifier circuit connected to light-emitting diode (LED) reporting units. The current generated from electrogenic bacteria in the sensing unit was amplified by the transistor and was transduced into LED illumination. The sensing units incorporated on the paper-based printed circuit boards (PCBs) absorbed bacteria-laden suspensions through capillary action, allowing for a rapid assessment ( less then 2 min) of their electrogenic potential. Two well-known exoelectrogens, Shewanella oneidensis MR1 and Pseudomonas aeruginosa PA01, and many other mutants of the latter were selected to demonstrate the practicality of the proposed sensor. The effectiveness for on-site and portable measurements was validated by testing solid wastewater samples randomly obtained from the environment. Thus, the system described in this work highlights a novel form of a scalable, high-throughput sensing array for simple and rapid quantification of bacterial electrogenicity.We present a tyrosinase-conjugated zinc oxide-reduced graphene oxide (Tyr/ZnO-rGO) nanocomposite system as a biosensing test-bed for rapid and sensitive detection of dopamine (DA). The bioelectrodes (Tyr/ZnO-rGO/ITO) were designed by covalently immobilizing tyrosinase enzyme on spin-coated films of ZnO-rGO nanocomposite prepared via self-assembly approach. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) showed fast electron transfer kinetics of ZnO-rGO/ITO electrode. The response studies of the Tyr/ZnO-rGO/ITO bioelectrode revealed ultrafast (0.34 ± 0.09 s) detection of DA in a wide linear dynamic range of 0.1-1500 pM. The significant performance of the biosensor in terms of low detection limit (8.75 ± 0.64 pM) and high sensitivity (39.56 ± 0.41 μA nM-1) values is attributed to the fast and unhindered electron transfer mechanism of ZnO-rGO matrix having low electrochemical band gap. The nanoplatform exhibited high selectivity toward DA in human sera, and remained stable up to 3 months at 4 °C, representing its suitability for clinical applications.A simple and highly sensitive photoelectrochemical biosensor towards L-phenylalanine, as a kind of typical essential amino acid and phenylketonuria biomarker was developed on a surface molecular imprinted (MIP) polydopamine-coated CdS/CdSe/Zn heterojunction. Hierarchical marigold flower-like Zn layer decorated by n-type dichalcogenides interfacial heterojunction was successfully designed and synthesized on Ti foil for PEC converter by in situ electrodeposition. A visible-light-driven molecular imprinting film was prepared through the electropolymerization of dopamine in the presence of L-Phe as biomarker. The combination of bio-MIP and photoelectrochemistry overcomes the defects of the PEC method, which is the absence of selectivity, and offers a new PEC sensor with high sensitivity and selectivity based on visible-light-driven heterojunction and biopolymer-enhanced strategy. The unique interfacial between the Zn marigold flower layer as low work function support and CdS/CdSe n-n heterojunction as well as n-type characteristics of polydopamine imprinted by L-Phe biomarker drastically increase the light trapping and absorption in the visible range, and dramatically inhibit the charge carrier recombination, which is crucial for boosting the Bio-PEC activity. Photocatalytic, electrocatalytic and physicochemical properties of the above-mentioned layers were fully characterized. As-prepared PEC biosensor displayed superb performance for the detection of L-Phe biomarker in the optimized condition obtained from central composite design modeling, showing two linear range 0.005-2.5 and 2.5-130 μM and a low detection limit of 0.9 nM. This work suggests that such L-Phe-imprinted polydopamine-coated Zn/CdS/CdSe heterojunction is greatly promising for being applied in photoelectrochemical biosensing with high photo-electron conversion efficiency.Magnetic hierarchical flower-like Co3O4 spheres (Co3O4 nanoflowers) were facilely prepared via one-step surfactant-free and template-free wet chemical route at room temperature. The formation mechanism of Co3O4 nanoflowers was explored. The as-prepared Co3O4 nanoflowers exhibited excellent tetra-enzyme mimetic activities, including oxidase-like, peroxidase-like, catalase-like and superoxide dismutase (SOD)-like activity. The catalytic mechanism of the Co3O4 nanoflowers was studied in detail. The oxidase-like catalytic activity of Co3O4 nanoflowers was derived from the inherent oxygen vacancies of Co3O4, while the peroxidase-like catalytic activity originated from the •OH radical generated by hydrogen peroxide (H2O2). Only one specific enzyme mimics reaction with Co3O4 nanoflowers can be obtained by inhibiting specifically other nanozymes via varying pH, adding appropriate scavengers or selecting its specific substrate. Further, the steady-state kinetic and catalytic performance of the oxidase-, peroxidase- and catalase mimics of Co3O4 nanoflowers were studied.
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