Study on Electrochemical Behavior of Ibuprofen by Linear Scanning Polarography

The electrochemical behavior of ibuprofen was studied by linear scanning polarography and cyclic voltammetry.In a B-R buffer solution of pH 2.79,a sensitive adsorption wave given by ibuprofen was observed at -1.298 V (vs.SCE).Linear relationship between values of peak current of 1st derivative plot of linear scanning and mass concentration of ibuprofen in the range of 10.0-1 000.0 mg·L-1 was obtained,with a detection limit (3S/N) of 5 mg·L-1.Precision of the method was tested at the concentration level of 100.0 mg·L-1 for 6 replicate determinations,and the value of RSD found was 1.62%.Recovery of the method was tested by standard addition method,and values of recovery found were in the range of 96.2%-103.8%.It was shown that,at a low scanning rate,the reduction of ibuprofen at the electrode is an irreversible process,controlled mainly by diffusion;and at a high scanning rate,the reduction wave is due to quasi-reversible process and behaving with adsorptive property.