Method development for determination of parabens by high performance liquid chromatography coupled with G/PVP/Pani modified carbon electrode

Abstract

In this research, a nanocomposite of graphene (G), polyvinylpyrrolidone (PVP) and polyaniline (PANI) modified onscreen-printed carbon electrode (SPCE) using electrorospraying technique was developed for simultaneous determination of five parabens; methyl paraben (MP), propyl paraben (PP), butyl paraben (BP) and isobutyl paraben (IBP), in beverages and cosmetic products by high-performance liquid chromatography (HPLC). PVP and PANI were used as dispersing agents of graphene, and also for the enhancement of electrochemical conductivity of the electrode. Under the optimal conditions, i.e. the mobile phase of 0.05 M phosphate buffer solution (pH 6): acetonitrile (60:40, %v/v) with an amperometric detection at a controlled potential of +1.2 V vs Ag/AgCI, the chromatogram of five parabens obtained from the modified SPCE exhibited well defined peaks and higher current response than those of its unmodified counterpart. The calibration curves of five parabens provided a similar linear range between 0.1 and 30 µg/mL with the correlation coefficient (R²) higher than 0.99 (n=3). The limits of detection (LOD) and the limits of quantitation (LOQ) of five parabens were found In the range of 0.01 to 0.03 µg/mL and 0.04 to 0.10 µg/mL, respectively. Furthermore, this Proposed has been applied for the simultaneous determination of five parabens in a soft drink sample and a cosmetic product with satisfactory results.