Poly(Amino Hydroxy Naphthalene Sulphonic Acid) Modified Glassy Carbon Electrode; An Effective Sensing Platform for the Simultaneous Determination of Xanthine and Hypoxanthine
Manna Rachel Mathew, K. Girish Kumar
Abstract
A rapid, simple and reliable electrochemical sensor for the simultaneous determination of xanthine (XA) and hypoxanthine (HX) based on poly(4-amino-3-hydroxy naphthalene-1-sulphonic acid) [ p (AHNSA)] modified glassy carbon electrode (GCE) is reported here. The proposed sensor permit well resolved and well separated peaks for XA and HX in 0.1 M NaOH at comparably lowest potential by square wave voltammetric (SWV) technique. The experimental parameters required for the electroxidation of both XA and HX are optimised. For simultaneous determination, the oxidation peak current showed a linear variation in the concentration range 4.0 × 10 −4 –3.0 × 10 −6 M and 2.0 × 10 −4 −6.0 × 10 −6 M with detection limits 7.1 × 10 −7 M and 1.5 × 10 −6 M for XA for HX, respectively. The mechanistic aspects were studied by linear sweep voltammetry (LSV) and the electrode processes were found to be diffusion controlled. The developed sensor was found to have promising application in some real samples like tea and coffee and in physiological samples with good selectivity and sensitivity.