Application of orthogonal functions to spectrophotometric analysis of weakly absorbing compounds in tablets

Abstract
Glenn's method of orthogonal functions has been applied to correct for irrelevant absorption during the analysis of tablets of chlorpheniramine maleate, phenyltoloxamine dihydrogen citrate, diphenhydramine hydrochloride and ephedrine hydrochloride. The results suggest that the method can be used for routine analysis.