VOLTAMMETRIC DETECTION OF GLOBULIN WITH IONIC LIQUID MODIFIED ELECTRODES

ABSTRACT In the present study, the ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate (IL)) modified pencil graphite electrodes (PGEs) were developed for electrochemical detection of protein, globulin (GLB). The microscopic characterization of PGE and IL modified PGE was performed by scanning electron microscopy (SEM). The electrochemical behaviour of IL modified PGEs was investigated by cyclic voltammetric (CV) technique and electrochemical impedance spectroscopic (EIS) technique. Differential pulse voltammetric (DPV) technique was used for measuring the oxidation signal of globulin. Under the optimum experimental conditions, a linear concentration range of globulin was obtained in the range of 20 to 100 nM and the detection limit was found to be 7.64 nM. The selectivity of our assay to GLB was also tested against to Glutathione, Glucose, L-Cysteine, L-Methionine, L-Tryptophan individually as well as in the mixture sample (1:1) of Globulin:Glutathione, GLB:glucose, GLB:L-Cysteine, GLB:L-Methionine and GLB:L-Tryptophan.