Application of Vierordt’s method for estimation of Tapentadol HCl and Paracetamol in combined dosage form by UV spectrophotometry

Abstract

Application of Vierordt’s method in the development and validation of a simple, accurate and sensitive UV spectrophotometric method for quantification of paracetamol and tapentadol HCl in combined dosage form was studied. Estimation of paracetamol and tapentadol HCl was done by measuring the absorbance at two wavelengths 257 nm and 272 nm, 𝜆max of paracetamol and tapentadol HCl respectively in 0.1 N HCl. The linearity was observed at the concentration ranges of 4-28 𝜇g/mL with correlation coefficient values (R2) 0.9986 and 9991 for paracetamol and tapentadol HCl respectively. The percentage recovery at different concentration levels was found to be 99.18 to 100.02 % for paracetamol and 98.47 to 100.09 % for tapentadol HCl indicating the accuracy of the method. Limit of detection and limit of quantification for paracetamol were found to be 0.15 μg/mL and 0.48 μg/mL and 0.10 μg/mL and 0.31 μg/mL for tapentadol HCl. The proposed Vierordt’s method was considered to be simple, accurate, economical and sensitive for the quantitative analysis of paracetamol and tapentadol HCl in combined dosage form as tablets. The proposed method could be used successfully for routine testing of paracetamol and tapentadol HCl in quality control samples from pharmaceutical industry.