4TH-DERIVATIVE SPECTROPHOTOMETRIC DETERMINATION OF SOME PHARMACEUTICAL SUBSTANCES

In this paper the fourth-derivative spectrophotometric method for the assaying of some pharmaceutical combinations was described. It was ana lysed the conditions for the determination of certain nan-narcotic ana lgoantipiretics(acetylsalicylic acid, paracetamol and salicylamide), a naleptics (caffeine), vitamins (L-ascorbic acid), antioxidants (butyla ted hydroxyanisole), sedatives and hypnotics (phenobarbital and secoba rbital) and antihistaminics (promethazine). For the determination of n umbers of mentioned substances ''zero-crossing'' technique was applied , but for some of them the caracteristic peak amplitude had to be corr ected. The investigated criterias were applied for the assaying of the se substances in different pharmaceutical combinations. This method is simple, rapid, precize and accurate and could be applied for the quan titative analysis of pharmaceutical preparations.