Spectroscopic and HPLC methods for the determination of alendronate in tablets and urine.

Two methods (spectrophotometric and HPLC) have been developed and validated for the analysis of alendronate sodium in tablet dosage form. Both methods depend on the ability of alendronate sodium to react with o-phthalaldehyde (OPA) at basic pH to produce a light-absorbing derivative. The derivative was found to possess absorption maximum at 330nm where neither the derivatizing agent nor the analyte had any absorption.