UV-VIS Determination of Acetylsalicylic Acid in Aspirin Tablets Using Different Solvents and Conditions

Abstract

Acetylsalicylic acid is the salicylic drug which is commonly used like analgesic, antipyretic and anti-inflammatory drug. There are a lot of methods for analysis, but we decided for UV-VIS spectroscopy. In this paper are correlation results from UV-VIS determination of acetylsalicylic acid in six aspirin tablets from different manufacturers in Bosnia and Herzegovina using two different methods and changing parameters in first one. Standards and samples are prepared at the same way. First method was done using 1 M NaOH for degradation of acetylsalicylic acid and development of colors with 0.02 M FeCl3 in 0.03 HCl (optimal pH = 1.6). For this analysis we made (multiple times) five standards with different concentrations (50–250%), changing pH of FeCl3/HCl solution (0.60, 1.60, 1.95). Then, we changed the concentration range of standards: 50–250, 80–120, 80–160%. The best absorbance results were at 530 nm using FeCl3/HCl solution at pH 1.60, so we analyze samples using that solutions. The second method was dissolving standards and samples in concentrated ethanol and measuring absorbance at 227 nm. Both method gave good results and can be used for pharmaceutical research.