Carbimazole

A simple and reproducible method was developed for carbimazole by Reverse Phase High Performance Liquid Chromatography (RP-HPLC). Carbimazole was separated on C18 column [4.6x250mm, particle size 5μm] at the UV detection of 291nm. Methanol and OPA (0.1%) was used as a mobile phase with various ratios and flow rates, eventually 80:20 v/v Methanol and OPA (0.1%) was being set with the flow rate of 0.7mL/min. The statistical validation parameters such as linearity, accuracy, precision, inter-day and intra-day variation were checked, further the limit of detection and limit of quantification of carbimazole concentrations were found to be within the limits. Recovery and assay studies of carbimazole were within 99 to 102% indicating that the proposed method can be adoptable for quality control analysis of carbimazole.

Development and validation of an analytical UV derivatives spectrophotometric method to quantify carbimazole as a single active principle in pharmaceutical formulation were done. Based on the spectrophotometric characteristics of carbimazole, a signal of first (314 nm), second (300 nm), third (289 nm), fourth (320 nm) order derivative spectrum was found to be adequate for quantification. The method obeyed Beer's law in the concentration range of (2-18 µg/ml) with square correlation coefficient (r2 = 0.999). The mean percentage recovery was found to be 99.56 ± 0.7179. As per ICH guidelines the results of the analysis were validated in terms of linearity, precision, accuracy, limit of detection and limit of quantification, and were found to be satisfactory. Key Words: Carbimazole, Derivative spectrophotometry, ICH, Validation.