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A non-invasive method for detecting glucose is pursued by millions of diabetic patients to improve their personal management of blood glucose. In this work, a novel CuO nanoparticles (NPs) decorated polycaprolactone@polypyrrole fibers modified indium-tin oxide (denoted as CuO/PCL@PPy/ITO) electrode has been fabricated by electrospinning combined with the electrodeposition method for non-enzymatic detection of glucose in saliva fluid. The electrospun composite fibers exhibit high sensitivity for the glucose detection. The synergistic effect between CuO and PPy together with the unique three-dimensional net structure contributes the reliable selectivity, good test repeatability, large-scale production reproducibility in massive way, the reasonable stability and a high catalytic surface area to the sensor. Quantitative detection of glucose is determined in the linear range from 2 μM to 6 mM and the lowest detection limit is 0.8 μM. The CuO/PCL@PPy/ITO electrode shows potential for the non-invasive detection of salivary glucose.

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The development of durable and efficient anode electrocatalysts is crucial for direct methanol fuel cells. In this paper, polyaniline (PANI) microtubes are firstly prepared by removing the polystylene (PS) core from PANI coated electrospun PS. The catalyst of PtNi/PANI@rGO is built by two steps: graphene oxide (GO) is mixed with PANI microtubes to obtain PANI@GO and then PANI@GO is used as a support material to load PtNi nanoparticles by reductive reaction while GO is reduced into rGO. The morphology, electronic structure and chemical structure of the catalysts are characterized by SEM, TEM, XPS and Raman spectroscopy, respectively. The electrochemical analysis of electrochemical impedance spectroscopy, cyclic voltammetry and chronoamperometric measurement are performed to analyze the electrocatalytic performance. The electrochemical results indicate that as-synthesized PtNi/PANI@rGO has the high activity toward methanol oxidation, and its mass activity is 1.7, 1.3 and 4.1 times higher than that of PtNi/PANI, PtNi/rGO and commercial Pt/C catalysts, respectively. The PANI microtubes not only improve the electron transfer kinetic but also help avoid the accumulation of graphene layers. The doping of Ni into Pt changes the surface electronic structure to elevate the catalytic activity and helps effectively improve the resistance to CO poisoning.

In this work, a multi-walled carbon nanotube-modified flexible poly(styrene-butadiene) fiber membrane material was prepared for the sensitive and selective electrochemical detection of dopamine (DA) in human serum and DA injection. The flexible fiber membrane prepared by electrospinning technology is expected to realize its application in wearable devices. The obtained conductive film-based electrochemical sensor can effectively minimize interference caused by ascorbic acid and uric acid. Under the optimized experimental conditions of differential pulse voltammetry, DA gives a linear response in the range of 1-650 μM (R 2 =0.996). The detection limit of DA (signal-to noise ratio=3) was determined to be 0.062 μM.