Quantitative Analysis of Acetylsalicylic Acid in Commercial Pharmaceutical Formulations and Human Control Serum Using Kinetic Spectrophotometry
Snežana S. Mitić*, Gordana Ž. Miletić, Aleksandra N. Pavlović, Snežana B. Tošić and Slavica M. Sunarića
Faculty of Sciences and Mathematics, Department of Chemistry, University
of Niš, Višegradska 33,
P.O. Box 224, 18000 Niš, Serbia
aFaculty of Medical Sciences, Bulevar Zorana Ðin|ica 81, 18000 Niš,
Serbia
* Corresponding author: E-mail:
mitich_s@yahoo.com
Abstract
The aim of this work is to develop a new kinetic spectrophotometric method
for the determination of acetylsalicylic acid (ASA) in pharmaceutical
formulations. In general, ASA analysis is not realised directly, and a previous
quantitative hydrolysis in a basic medium is necessary, converting ASA to
salicylate ions for its determination. The hydrolysis is carried out by sodium
hydroxide solution. The method is based on a ligand-exchange reaction. The
reaction was followed spectrophotometrically by monitoring the rate of
disappearance of the cobalt(II)-1-nitroso-2-naphthol complex in alkaline medium
at 410 nm. The optimum operating conditions regarding reagent concentrations and
temperature were established. The initial-rate method is adopted for
constructing the calibration curve, which was found to be linear over the
concentration range 0.72–9.00 µg mL–1. The optimized conditions
yielded a theoretical detection limit of 0.35 µg mL–1 based on the
3.3S0 criterion. The interference effects of certain ingredients of
powdery drugs, foreign ions and amino acids upon the reaction rate were studied
in order to assess the selectivity of the method. The results are validated
statistically and through recovery studies. The point hypothesis test have been
performed which indicate that there is no significant difference between the
proposed method and the reference method. The developed procedure was
successfully applied to the rapid determination of acetylsalicylic acid in
commercial pharmaceutical preparations and human control serum. The unique
features of this procedure are that determination can be carried out at room
temperature and analysis time is short. The newly developed method is simple,
inexpensive and efficient for use in the analysis of a large number of samples.
Keywords: Acetylsalicylic acid; kinetic spectrophotometry; validation; pharmaceutical analysis