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A novel hedgehog-shaped bismuth sulfide (HS-Bi2S3) nanostructure was for the first time explored as an electrode material for biosensing. Using cetyltrimethyl ammonium bromide (CTAB)-trimellitic acid as a composite soft template, the HS-Bi2S3 nanostructure was synthesized by a hydrothermal route. Using glucose oxidase (GOx) as the model, the HS-Bi2S3 nanostructure was employed to immobilize GOx for the development of a sensitive electrochemical glucose biosensor. The characterization of HS-Bi2S3 and the biosensor was performed by scanning electron microscopy, X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy and cyclic voltammetry. The hedgehog-shaped nanostructure of Bi2S3 has a large specific surface area to trap a large number of enzyme molecules, and at the same time greatly enhances the direct-electron-transfer action of enzymes. The HS-Bi2S3-based biosensor shows a wide linear range of 0.005–1.7 mmol L−1 and a low detection limit of 1.6 μmol L−1 for glucose at −0.37 V, which presents much better assay performance in comparison with the glucose biosensor without HS-Bi2S3. The present electrochemical biosensor displays high selectivity, good repeatability and stability, which can be used to measure blood glucose in real serum samples. [ABSTRACT FROM AUTHOR]

A titanium dioxide functionalized SnS2 nanocomposite was synthesized for the immobilization of glucose oxidase (GOx) to develop an enzymatic electrochemical glucose biosensor. Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry were used to characterize the nanocomposite and the glucose biosensor. The TiO2–SnS2 composite shows a larger surface area and GOx entrapped in this matrix maintains excellent bioactivity and stability. The constructed glucose biosensor responds to glucose linearly over two concentration ranges of 0.008 to 1.13 mM and 1.13 to 5.53 mM at a working potential of −0.45 V. The biosensor exhibits a high sensitivity (18.9 mA M−1 cm−2), low detection limit (1.8 × 10−6 M) and good repeatability. The present biosensor has excellent selectivity and can be successfully applied for the detection of glucose in serum samples. The advantages of the glucose biosensor show that a TiO2–SnS2 nanocomposite provides a new avenue for immobilizing proteins and fabricating excellent biosensors. [ABSTRACT FROM AUTHOR]