Acid chrome blue K (ACBK) was electropolymerized on the surface of a glassy carbon electrode (GCE) by cyclic voltammetric sweep in the potential range from –0.2 to 0.9 V. The characteristic of poly‐ACBK film was studied by different methods such as electrochemical impedance spectroscopy (EIS) and cyclic voltammetry. This modified electrode showed excellent electrocatalytic response to curcumin with the increase of the electrochemical responses. Under the optimal conditions a good linear voltammetric response could be obtained over the range of 1.0 × 10−7‐7.0 × 10−5 M and the detection limit was got as 4.1 × 10−8 M (S/N = 3). The method was successfully applied for the determination of curcumin in human urinev samples.

A new method for the determination of josamycin has been developed based on quenching of the fluorescence of 3-mercaptopropionic acid-capped CdTe quantum dots (MPA-CdTe QDs) by josamycin in ethanol. Reaction time, interfering substances on the fluorescence quenching, and mechanism of the interaction of CdTe QDs with josamycin were investigated. Under optimum conditions, the relative fluorescence intensity was linearly proportional to the concentration of josamycin between 12.0 and 120.0 µg mL −1 with a correlation coefficient of 0.9956 and a detection limit of 2.5 µg mL −1. The proposed method was successfully applied to commercial tablets, and the results were satisfactory, i.e. consistent with those of high-performance liquid chromatography (HPLC).