Linear sweep voltammetric determination of chondroitin sulfate based on its interaction with pyronine B

摘要

A new linear sweep voltammetric method was proposed for the detection of chondroitin sulfate(CS)by using pyronine B(PB)as electrochemical probe.In the selected pH 1.5 Britton-Robinson(B-R)buffer solution,PB has a sensitive linear sweep voltammetric reduction peak at-0,78 V(vs SCE).After the addition of CS into PB solution,the reduction peak current decreased apparently without the shift of reduction peak potential.The conditions for the interaction and electrochemical detection were optimized.Under the optimal conditions,the decrease of reduction peak current was proportional to the concentration of CS in the range of 2.0-50.0 mg/L with the linear regression equation as DELTA I_p''(nA)=23.90+83.43C(mg/L)(n=13,gamma=0.994)and the detection limit as 0.84 mg/L(3 sigma).Three synthetic samples were determined with satisfactory results and the stoichiometry of CS with PB was calculated by the voltammetric data.