SIMULTANEOUS DETERMINATION OF ASPIRIN AND ITS METABOLITE FROM HUMAN PLASMA BY UPLC-UV DETECTION: APPLICATION TO PHARMACOKINETIC STUDY

Abstract

A rapid and sensitive liquid chromatography method with UV detection for simultaneous measurement of aspirin (ASA) and salicylic acid (SA) was developed and validated completely in human plasma. ASA, SA, and Benzoic acid (BA) as internal standard were extracted via protein precipitation with Perchloric acid. An isocratic elution with binary mode was used to separate interference peaks using a C₁₈ Acquity column with only three minutes of analysis time. The linearity range was 15 to 6000 n g mL⁻¹. Calibration functions, LOQ, stability, intra- and inter-day reproducibility, and accuracy were estimated. The inter- and intra-day % CV for ASA and SA are ±15% and the percentage change of all stability samples with comparison samples were within 10%. The in vitro conversion of ASA to SA was also studied and it was controlled to keep at a minimum (<10%). With respect to other published methods this method is most sensitive in UV detection, as well as its sensitivity and throughput is comparable or even better than published LC-MS/MS methods. This method was successfully applied to a single dose Bioequivalence (BE) study of following administration of 81 mg enteric coated Aspirin tablets.

Keywords:

• aspirin
• Benzoic acid
• Bioequivalence/protein precipitation
• salicylic acid
• UPLC-UV

Notes

Each mean and % CV of intra-day accuracy and precision represent six observations (n = 6). The inter-day accuracy and precision are averages and % CV of three intra-day observations.

Each mean accuracy, % CV and % change of each stability represents six observations (n = 6) of corresponding QC levels.