Highly sensitive electrochemical detection of paracetamol using a reduced gamma-aminobutyric acid modified pencil graphite electrode via differential pulse voltammetry

Paracetamol (PAR) has a ubiquitous application in pharmaceutical formulations due to its activity in treating common disease symptoms. Electrochemical modification of gamma-aminobutyric acid onto pencil graphite electrode (GABA/PGE) was accomplished by gamma-aminobutyric acid (GABA) onto pencil graphite electrode (PGE) surface, followed by an electrochemical reduction of GABA to fabricate rGABA/PGE. GABA/PGE and rGABA/PGE's were performed characterization process by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and field emission scanning electron microscopy (FE-SEM) techniques in comparison to bare PGE. For the first time, the application of the fabricated rGABA/PGE in the determination of PAR was conducted by employing differential pulse voltammetry (DPV) technique. Two linear calibration curves were achieved for concentrations ranging from 0.8 to 100 mu M, with and correlation coefficients r2 = 0.9962 and r2 = 0.9952 with limit of detection (LOD) and limit of quantification (LOQ) equal to 0.18 mu M and 0.54 mu M, respectively. The recovery values obtained the use of rGABA/PGE to quantify PAR in pharmaceutical samples ranged from 99.91 to 101.71 %, indicating the method exhibits high sensitivity for detecting of PAR. The suggested methodology presented a convenient way to determine PAR in some common pharmaceuticals using a new sensor electrode.