In this present work, a sensitive electrocatalytic modified electrode based on 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP)/multiwalled carbon nanotubes (MWCNT) modified carbon paste electrode (CPE) was successfully developed. Electrochemical impedance spectroscopy, square wave voltammetry, chronocoulometry and cyclic voltammetry were used in prompt to evaluate the PMBP/MWCNT/CPE electrochemical capacity in detecting acetaminophen (APAP) in 0.1 M PBS pH 6.4. Under optimized conditions, PMBP/MWCNT/CPE displayed a well-defined electrocatalytic activity towards APAP oxidation in the linear responses which range from 1 μM to 1 mM (R2 = 0.991) with the LOD obtained at 0.245 μM while LOQ 0.816 μM. The presence of excess (10-fold and 25-fold) interferents such as sucrose, fructose, glucose, sodium chloride, sodium sulphate, potassium nitrate, lysine, potassium chloride and magnesium chloride as interferents was insignificant. The results presented in this study provide new perspectives on PMBP as a potential nanomaterial in the development of APAP sensors. As a conclusion, the PMBP/MWCNT/CPE revealed good stability, reproducibility, and repeatability, and was discovered to be relevant for usage in the pharmaceutical samples with satisfactory performance.

Emi Norzehan, Mohamad Mahbob, Mohamad Syahrizal Ahmad, Illyas Md Isa, Norhayati Hashim, Anwar Ul-Hamid, Mohamad Idris Saidin and Suyanta M. Si