Investigation of polyelectrolyte for electrochemical detection of uric acid in presence of ascorbic acid

Uric acid (UA) was detected in the presence of ascorbic acid (AA) at GC electrode by cyclic voltametry (CV) and differential pulse voltametry (DPV) in aqueous media of cationic polyelectrolyte (poly(diallyldimethylammonium chloride) (PDDA)). Both, UA and AA are anionic nature and electro-static attraction with cationic solution. This lowered their oxidation potentials and increased anodic current. In CV studies, the UA oxidation potential was decreased by 400 mV in the presence of PDDA along with increase in peak current. Effect of PDDA and pH on Epa and Ipa were also studied. About 360 mV difference in oxidation peak potentials was observed for AA and UA in PDDA media, which established a quick method for their simultaneous determination. The detection limit of UA in the presence of 200 folds AA was found as 1 μM with correlation coefficient of 0.994 and sensitivity of 0.05 μA μM−1. The proposed method has been also applied for determining the UA in human urine without any pretreatment, and found to be satisfactory.

Exploiting the polyelectrolyte environment for electrochemical detection of UA and AA at GC electrode.Figure optionsDownload as PowerPoint slideHighlights
► Simple, rapid and easy method.
► No need of any modified electrode.
► Sufficient peak potential separation between UA and AA.
► New material and approaches for electrochemical sensor.
► Also these material and approaches usefulness to other sensor.