Simultaneous determination of carisoprodol and aspirin in human plasma using liquid chromatography-tandem mass spectrometry in polarity switch mode: application to a human pharmacokinetic study

• Published in: Biomedical chromatography 2013-02, Vol.27 (2), p.179-185
• Main Authors: Sreenivasulu, Vudagandla, Ramesh, Mullangi, Kumar, Inamadugu Jaswanth, Babu, Ravi Vasu, Pilli, Nageswara Rao, Krishnaiah, Abburi
• Format: Article
• Language: English
• Subjects: aspirin; Aspirin - blood; Aspirin - chemistry; Aspirin - pharmacokinetics; carisoprodol; Carisoprodol - blood; Carisoprodol - chemistry; Carisoprodol - pharmacokinetics; Chromatography, High Pressure Liquid - methods; Drug Stability; human plasma; Humans; LC-MS/MS; Least-Squares Analysis; Liquid-Liquid Extraction; Male; method validation; pharmacokinetics; Reproducibility of Results; Sensitivity and Specificity; Tandem Mass Spectrometry - methods
• ISSN: 0269-3879; 1099-0801
• DOI: 10.1002/bmc.2766

ABSTRACT A simple, sensitive and rapid LC‐MS/MS‐ESI method has been developed and validated for simultaneous quantification of the carisoprodol and aspirin in human plasma. Carisoprodol was detected in positive ion mode, whereas aspirin was detected in negative ion mode. Carbamazepine and furosemide were used as internal standards (IS) for quantification of carisoprodol and aspirin, respectively. The extraction procedure involves a liquid–liquid extraction method with ter‐butyl methyl ether. Chromatographic separation was achieved on a Zorbax XDB‐Phenyl (4.6 × 75 mm, 3.5 µm) column using an isocratic mobile phase (5 mm ammonium acetate:methanol, 20:80, v/v) at a flow rate of 0.8 mL/min with a total run time of 2.2 min. A detailed method validation was performed as per the FDA guidelines. The standard curves found to be linear in the range of 25.5–4900 and 15.3–3000 ng/mL for carisoprodol and aspirin, respectively. The results met the acceptance criteria. Carisoprodol and aspirin were found to be stable in various stability studies. The validated method was successfully applied to a pharmacokinetic study following co‐administration of carisoprodol (250 mg) and aspirin (75 mg) tablets by oral route to human volunteers. Copyright © 2012 John Wiley & Sons, Ltd.