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• An enzyme-free sandwich-type electrochemical sensor for glucose detection was fabricated based on boronate complex. • Three-dimensional self-assembly monolayer was formed above uniformly dispersed gold nanoparticles array. • Electrochemical signals were not from faradic process of glucose oxidation but the secondary receptor FcBA. • The strategy exhibited excellent selectivity, wide linear range and low detection limit for glucose detection. • The proposed method showed promising prospection for glucose test in urine samples in psychological condition. In this article, a sandwich-type electrochemical sensor for selective determination of glucose based on the formation of glucose-boronic bidentate complex has been developed. 3-aminophenylboronic acid (m -APBA) was immobilized on the gold nanoparticles modified ITO electrode with the linker molecule 4-mercaptobenzoic acid (p -MBA). Then, glucose was captured by boronic acid group from m -APBA as the primary receptor and further grafted with an electroactive ferroceneboronic acid (FcBA) as the secondary receptor to form the sandwich-type sensor for selective detection of glucose. For comprehensively understanding the effect of the charge and structure of the terminal boronic acid group of 3-APBA on its binding to glucose, surface p K a was studied by electrochemical titration method, and it was proved the feasibility of examining glucose in physiological condition by the sandwich-type electrochemical sensor. The electrochemical characteristics of the as-prepared sensor were investigated by using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The electrochemical sensor displayed a linear detection range of glucose from 0.5 mmol L−1 to 30 mmol L−1, with detection limit of 43 µmol L−1. The sensor exhibited good performance in selectivity study with the coexistence of galactose, fructose, mannose and other common interferences in physiological environment, such as, uric acid, ascorbic acid and dopamine. The as-prepared electrode with high sensitivity, good stability and reproducibility as well as excellent biocompatibility made it promising for the development of enzyme-free sensors. [ABSTRACT FROM AUTHOR]

In this communication, for the first time, an easy preparation method of nickel–iron (Ni–Fe) hybrid nanocubes for glucose oxidation, which is highly efficient in alkaline media, is described. As an impressive redox probe for glucose, the Ni–Fe hybrid nanocubes exhibit many remarkable sensing performances, for example, low-response time (7 s), broad detection range (from 10 μM to 20.5 mM), and low detection limit (0.64 μM, S/N = 3). The selectivity, reliability and stability of the Ni–Fe hybrid nanocubes for glucose oxidation are also investigated. The glucose sensor based on Ni–Fe hybrid nanocubes shows a superior sensing performance to that of Ni-based or Fe-based electrochemical sensors. Furthermore, the Ni–Fe hybrid nanocubes were used to detect glucose in real samples of human blood serum. All the findings demonstrate that the glucose sensor based on Ni–Fe hybrid nanocubes is successful for glucose detection and shows promise for future applications in medical diagnostics, the food industry and biological processes. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Accurate determination of acetaminophen concentration is essential for studying the metabolic status of acetaminophen in clinical practice. In this study, nickel phosphide was used for electrochemical detection of acetaminophen for the first time. An electrochemical acetaminophen sensor based on Ni2P nanosheets was successfully constructed and the sensor showed many convincing properties: (a) a good linear range (0.5 μmol/L—4.5 mmol/L); (b) a moderate sensitivity (131.1 μA·mmol–1·L·cm–2); (c) a low detection limit (0.107 μmol/L). In addition, the sensor also showed excellent selectivity, robust stability and reliable repeatability. Further experiments demonstrate that the prepared sensor can be used for quantitative detection of acetaminophen in commercial medical drugs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel L-Cysteine self-assembled gold nanoparticles modified indium tin oxide electrode (ITO/Au/L-Cys) was obtained through a facile two step. • Comparing to bare Au, ITO/Au/L-Cys displays a highly sensitive and selective behavior for DA in the interference of UA. • ITO/Au/L-Cys exhibits an excellent electrocatalytic activity towards DA with the linear range of 2 μM ∼ 400 μM and a limit of detection reaches up to 0.6 μM. A novel L-Cysteine self-assembled gold nanoparticles modified indium tin oxide electrode (ITO/Au/L-Cys) was fabricated by facile steps of electro-deposition and immersion in solution. The as-prepared ITO/Au/L-Cys electrode is investigated as a potential electrochemical sensor for dopamine (DA) in the interference of Uric Acid (UA). It combines the catalytic advantages of the Au(1 1 1)-like nanoparticles array with self-assembled L-Cysteine. The biosensor displays a highly sensitive and selective behavior for DA in the present of UA. The peak currents response to DA is linear with their concentrations in the range of 2 μM ∼ 400 μM. In addition, a limit of detection reaches up to 0.6 μM (S/N = 3). Consequently, the high sensitivity, stability and excellent biocompatibility of ITO/Au/L-Cys electrode made it as a promising DA sensor. [ABSTRACT FROM AUTHOR]

In this article, for the first time, a novel, label-free and inherent electroactive redox biosensor based on ultrathin Au-Pt nanowire-decorated thionine/reduced graphene oxide (AuPtNWs/THI/rGO) is developed for carcinoembryonic antigen (CEA) detection. Ultrathin AuPtNWs are prepared by a one-pot synthesis method without the use of any stabilizer or template. The AuPtNWs/THI/rGO composites are obtained by the THI/rGO composites surface functionalized with -NH2 group employed as a support for loading ultrathin AuPtNWs by coordination. The AuPtNWs/THI/rGO composites not only favor the immobilization of antibody but also facilitate the electron transfer. It is found that the resultant AuPtNWs/THI/rGO composites can be designed to act as a sensitive label-free electrochemical immunosensor for CEA determination. Under the optimized conditions, the linear range of the proposed immunosensor is estimated to be from 50 fg·mL−1 to 100 ng·mL−1 (R= 0.998) and the detection limit is estimated to be 6 fg·mL−1 at a signal-to-noise ratio of 3, respectively. The prepared immunosensor for detection of CEA shows high sensitivity, reproducibility and stability. Our study demonstrates that the proposed immunosensor has also been used to determine CEA successfully in diluted blood samples. [ABSTRACT FROM AUTHOR]