Qualitative and Quantitative Estimation of Acyclovir in Human Plasma by Using LC-MS/MS

Acyclovir is used orally for the treatment and prophylaxis of initialsand recurrent episodes of genital and labial herps and varicells in immunocompetent individuals. A simple, sensitive, high throughout liquid chromatography Tandem Mass Spectrometry-Waters Quattro Premier XE method (LC-MS/MS) method has been developed for the simultaneous estimation of acyclovir in human plasma using ganciclovir as internal standard. The method involved solid phase extraction of the analytes and IS from 0.5 mL human plasma with no reconstitution and drying steps (direct injection of eluate). The chromatographic separation was achieved on a Hypersil GOLD C18 analytical column using isocratic mobile phase, consisting of mobile phase containing ammonium acetate and acetonitrile (25:75%, v/v) were used. The retention time for internal standard and acyclovir were 1.14 min and 1.81 min respectively and overall chromatography run time was 2.26 minutes. Lower limit of detection and lower limit of quantification (LLOQ) were identifiable and reproducible at 5.0ng/mL and 30.0ng/mL. This method was used successfully to a bioequivalence or pharmacokinetic study in 36 healthy human subjects after single oral estimation of 200mg acyclovir capsule formulation under fasting and non-fasting conditions.