Sensitive and Selective Analytical Method for the Quantification of Two Potential Genotoxic Impurities in Azilsartan Drug Substance by using LC-MS/MS with Multiple Reaction Monitoring (MRM mode)
Chandramohan Alluri
Department of Chemistry, Institute of Science, GITAM (Deemed to be University), Rushikonda, Visakhapatnam, India.
Kiran Kumar Naramsetti
Department of Chemistry, Institute of Science, GITAM (Deemed to be University), Rushikonda, Visakhapatnam, India.
G. Veera Raghava Sharma *
Department of Chemistry, Institute of Science, GITAM (Deemed to be University), Rushikonda, Visakhapatnam, India.
*Author to whom correspondence should be addressed.
Abstract
The main aim of the present study to Synthesize,method development and method validation for quantification of two potential genotoxic impurities i.e., Methyl(Z)-2-ethoxy-1-((2'-(N'-hydroxycarbamimidoyl)-[1,1'-biphenyl]-4-yl) methyl)-1H-benzo[d]imidazole-7-carboxylate(Impurity-A) and 2-ethoxy-1-((2'-(N'-hydroxycarbamimidoyl[)-[1,1'-biphenyl]-4-yl)methyl)-1H-benzo[d]imidazole-7-carboxylicacid(Impurity-B) by using LC-MS/MS MRM mode at trace level determination inAzilsartan drug substance. The new LC-MS/MS MRM mode method was developed by using Inertsil ODS-3V 150x4.6mm,5µm column as stationary phase. The mobile phase used is the composition of 10Mm Ammonium formate pH3.00buffer:Acetonitrile(9:1)%v/v as mobilephase-A and 10Mm Ammonium formate pH3.00buffer:Acetonitrile(2:8)%v/v as mobile phase-B, isocratic elution of mobile phase-A and Mobile phase-B (60:40)v/v at flow rate of 0.8mL/min.The concentration limits of the both genotoxic impurities were calculated a limit of 37.5ppm based on the concept of TTC (threshold of toxicological concern) and MDD (maximum daily dosage which is 40mg/day for Azilsartan drug substance.The limit of detection(LOD) was found to be 1.4ppm for both Impurity-A and Impurity-B.The limit of quantification(LOQ) for Impurity-A was 4.7ppm and Impurity-B was 4.5ppm respectively The method was found to be linear from 4.7ppm to 78.4ppm for Impurity-A (correlation coefficient:1.000) and 4.5ppm to 75.7ppm for Impurity-B (correlation coefficient:0.999). The method was precise and found percentage of relative standard deviation for six replicate sample preparations of Impurity-A and Impurity-B was below 5.0%. The method accuracy was confirmed based on the recovery studies. Based on the method validation study method was sensitive and selective for quantification both genotoxic impurities.
Keywords: LC-MS/MS, MRM (Multiple reaction monitoring, TTC (Threshold of toxicological concern), MDD (Maximum daily dosage), Azilsartan, validation