Determination of Salicylic Acid in Aspirin by Derivative Ratiospectrophotometry
WEI Yong feng, YAN Hong tao (Department of Chemistry, Northwest University, Xi’an, 710069)
A derivative ratiospectrophotometry for determination of microamount of salicylic acid in aspirin is developed. When large amount of aspirin coexsists, microamount of salicylic acid can be determined. The peak height of derivative ratiospectra at 300nm was proportional to the salicylic acid concentration with a linear correlation coefficient of 0.9994. The limit of detection was 0.005%, and the average recovery for determination of aspirin powder sample is between 95.0%～102.5%.