In this work, a new type of ultrasmall Pt nanoclusters (Pt NCs) was prepared via a facile one-pot approach by using yeast extract as the reductant and stabilizer. Besides their excellent water solubility, these yeast extract-stabilized Pt NCs also possess attractive peroxidase mimicking property. They can efficiently catalyze the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) in the coexistence of hydrogen peroxide (HO). Catalytic mechanism analysis suggested that the peroxidase mimicking activity of these Pt NCs might originate from their characteristic of accelerating electron transfer between TMB and HO, and their enzymatic kinetics followed typical Michaelis-Menten theory. On the basis of these findings, we developed a new highly sensitive colorimetric method for glucose detection, and the limit of detection was calculated as low as 0.28 μM (S/N = 3). Further application of the present system for glucose detection in human serum has been successfully demonstrated, suggesting its promising utilization as robust peroxidase mimics in the clinical diagnosis, pharmaceutical, and environmental chemistry fields.

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One-dimensional (1D) bimetallic nanowire materials have attracted much more attention in electroanalysis because of their unique physical and chemical properties. In this work, we further extended the application field of the PdPt bimetallic alloy nanowires (PdPt BANWs) structure and successfully fabricated a novel PdPt BANWs-based electrochemical sensor for sensitive detection of ascorbic acid (AA). It was found that the PdPt BANWs on the electrode exhibited remarkable electrocatalytic activity toward AA oxidation and could be used for sensitive detection of AA in a wide linear range (0.01-0.97 mM) with a high sensitivity of 467.9 mA mM À1 cm À2 . The detection limit is as lower as 0.2 mM (S/N ¼ 3). Moreover, the electrochemical sensor also exhibited good selectivity, reproducibility and stability, and had been successfully applied to detection of AA in serum samples and commercial vitamin C tablets with satisfactory results.