Spectrophotometric determination of acyclovir and amantadine hydrochloride through metals complexation

A simple spectrophotometric method for determination of some antiviral drugs, such as acyclovir and amantadine hydrochloride in pure and dosage forms, have been developed. The proposed method is based on the reactions of the selected drugs and metals. Acyclovir was reacted with copper (II) and cobalt (II) using a borax/sodium pH 9 hydroxide buffer, and in a non-aqueous medium using 1% pyridine in methanol, respectively. The formed complexes were absorbed maximally at A, 290 nm and at X 287 nm. The method determined from 112-1620 mug/mL of acyclovir, with a mean percentage of recovery of 99.32 +/- 0.63 and of 98.77 +/- 0.70 for copper (II) and cobalt (III), respectively. The suggested method was applied to a Novirus capsule, and its validity was ascertained by the standard addition technique. In addition, amantadine hydrochloride was allowed to react with iron (III) at pH 3 adjusted with 0.1 M ammonium hydroxide. The formed complex absorbed maximally at lambda 295 nm. This method determined from 94-940 mug/mL of amantadine hydrochloride with a mean percentage of recovery of 99.49 +/- 0.57. The suggested method was applied to an Adamine capsule, and its validity was ascertained by the standard addition technique.