Effective Determination of Acetaminophen Present in Pharmaceutical Drug Using Functionalized Multi-Walled Carbon Nanotube Film

Carboxylic acid functionalized multi-walled carbon nanotube (f-MWCNTs) was synthesized by simple acid treatment of pristine multi-walled carbon nanotube. The surface morphology of f-MWCNTs showed the existence of functional groups on the outer sidewalls of f-MWCNTs. These functional groups, –OH and C=O species of carboxylic acid on f-MWCNTs were confirmed by Fourier transform infrared spectroscopy. The f-MWCNT was applied to modify the glassy carbon electrode (GCE) to study the electrocatalysis of acetaminophen. The electrochemical studies showed better diffusion coefficient with stable signal, enhanced effective area and reduced charge transfer resistance results in presence of f-MWCNTs film on GCE. The f-MWCNTs film modified GCE also showed enhanced electrocatalysis towards acetaminophen. The sensitivity of f-MWCNTs film towards acetaminophen (9.6 μA μM-1 cm-2) was higher than the value obtained for bare GCE (0.33 μA μM-1 cm-2). Similarly, the limit of detection of acetaminophen at f-MWCNTs film (39.8 nM) was lower than other electrodes. The DPV and selectivity studies revealed that f-MWCNTs modified GCE can be efficiently applied for acetaminophen determination in real samples.