Development and validation of spectrophotometric method for determination of gabapentin in bulk and pharmaceutical dosage forms based on Schiff base formation with salicylaldehyde

Abstract

A sensitive, simple, and economic spectrophotometric method was developed and validated for the determination of gabapentin in pure form and pharmaceutical preparations. The method is based on Schiff base condensation reaction of the primary amino group of gabapentin with salicylaldehyde reagent in the presence of acetate solution at 45°C for 20 minutes. The obtained yellow-colored derivative in methanolic medium showed absorption maxima at 403 nm. Under the optimum conditions, Beer's law was obeyed in the concentration range of 6 to 100 μg/ml with correlation coefficient value of 0.9961. Limit of detection and limit of quantification were found to be 1.16 and 3.48 μg/ml, respectively. The validity of the described method was assessed according to the International Conference on Harmonization guidelines. The mean percentage recoveries ± SD were 100.57 ± 1.5 by applying the standard addition technique. The method was repeatable and precise (RSD ≤ 0.61% and ≤ 1.34%, respectively) and was successfully applied for the determination of the investigated drug in its pharmaceutical dosage form without detectable interference from the additives, hence, can be suggested for routine analysis of the gabapentin.