Determination of Oligomer Content in Benzonatate Drug Substance by HPLC

Abstract

A reverse-phase liquid chromatographic method has developed and validated to determine oligomer content in Benzonatate Drug substances. This method has a separation of relatively few monomer units, which constitutes an oligomer with a minimum adequate chromatographic resolution of 1.0 from each of the subject component peaks. The separation achieved using Phenomenex Luna C18 (250 X 4.6 mm) 5 µm column at a flow rate of 1.0 ml/min with an isocratic elution method. The mobile phase consisting of 0.25% Ammonium formate buffer and methanol in the ratio 350:650 (v/v), respectively. The Oligomer compounds detection carried out at UV 310 nm, and the LC method validated as per the current ICH Q2 guidelines. The method is effectively validated and proved to be precise, specific, linear, robust, and rugged to quantitate oligomer content in Benzonatate drug substance.