Attapulgite with poly(methylene blue) composite film–Electrocatalytic determination of ascorbic acid

A conductive composite film consisted of natural nanostructure attapulgite (AT) with poly(methylene blue) (PMB) was constructed on glassy carbon (GC) electrode. The electrode exhibited an effective electrocatalytic activity towards the oxidation of ascorbic acid (AA) and well-defined oxidation peaks were observed in 0.1 M phosphate buffer solutions (PBS, pH 7.0) via cyclic voltammetry. Linear calibration plot was obtained over the range of 1.0 × 10−5 to 5.0 × 10−2 M for ascorbic acid with the detection limit value of 1.0 × 10−6 M. The main interfering factor in biological samples was experimentally excluded. In addition, UV–Vis spectra were applied to reveal the formation of the nanocomposite film of PMB-AT.