Validated Specific HPLC-DAD Method for Simultaneous Estimation of Paracetamol and Chlorzoxazone in Presence of Five of Their Degradation Products and Toxic Impurities.

Validated Specific HPLC-DAD Method for Simultaneous Estimation of Paracetamol and Chlorzoxazone in Presence of Five of Their Degradation Products and Toxic Impurities. Drug Dev Ind Pharm. 2020 Sep 07;:1-28 Authors: El-Yazbi AF, Guirguis KM, Bedair MM, Belal TS Abstract This work demonstrates a specific and reliable HPLC with diode array detection (DAD) method for the simultaneous estimation of paracetamol (PAR) and chlorzoxazone (CZ) in presence of five of their degradation products and toxic impurities; namely; 4-aminophenol (AP), 4-nitrophenol (NP), acetanilide (AT), 4-chloroacetanilide (CA) and 2-amino-4-chlorophenol (ACP). Successful chromatographic separation was accomplished using Waters Symmetry C8 column (3.9 × 150 mm, 5 μm) with gradient elution of the mobile phase consisting of 0.05 M phosphate buffer pH 7.5 and methanol. The gradient elution started with 5% (by volume) methanol ramped up linearly to 50% in 10 min, and then maintained at this percentage afterwards till the end of the run. The mobile phase was pumped at a flow rate of 1.0 mL/min. The multiple wavelength detector was adjusted at 244 and 285 nm to quantify PAR and CZ, respectively. Additionally, the wavelength 270 nm was found suitable for monitoring separation of the entire mixture of PAR, CZ and their impurities. Seven peaks eluted with excellent resolution at retention times 3.4, 5.7, 8.0, 10.1, 10.8, 13.5 and 14.4 min for AP, PAR, NP, A...
Source: Drug Development and Industrial Pharmacy - Category: Drugs & Pharmacology Tags: Drug Dev Ind Pharm Source Type: research