title: Simultaneous quantification of lopinavir and ritonavir in human plasma by high performance liquid chromatography coupled with UV detection.
abstract: High performance liquid chromatography was coupled with UV detection for simultaneous quantification of lopinavir (LPV) and ritonavir (RTV) in human plasma. This assay was sensitive, accurate and simple, and only used 200 μL of plasma sample. Samples were liquid-liquid extracted, and diazepam was used as an internal standard. The chromatographic separation was achieved on a C18 reversed-phase analytic column with a mobile phase of acetonitrile-sodium dihydrogen phosphate buffer (10 mmol L(-1), pH 4.80) (60:40, v/v). UV detection was conducted at 205 nm and the column oven was set at 40°C. Calibration curves were constructed between 0.5-20 μg mL(-1) for LPV and 0.05-5 μg mL(-1) for RTV. The relative standard deviations were 2.16%-3.20% for LPV and 2.12%-2.60% for RTV for intra-day analysis, and 2.34%-4.04% for LPV and 0.31%-4.94% for RTV for inter-day analysis. The accuracy was within 100%±10%. The mean extraction recoveries were 79.17%, 52.26% and 91.35% for RTV, LPV and diazepam, respectively. This method was successfully applied to human plasma samples from patients orally administered a salvage regimen of lopinavir-ritonavir tablets.
authors.affiliation: Department of Infectious Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences-Peking Union Medical College, Beijing 100730, China.
authors.forename: Huijuan
authors.initials: H
authors.lastname: Kou
authors.forename: Min
authors.initials: M
authors.lastname: Ye
authors.forename: Qiang
authors.initials: Q
authors.lastname: Fu
authors.forename: Yang
authors.initials: Y
authors.lastname: Han
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Du
authors.forename: Jing
authors.initials: J
authors.lastname: Xie
authors.forename: Zhu
authors.initials: Z
authors.lastname: Zhu
authors.forename: Taisheng
authors.initials: T
authors.lastname: Li
mesh_terms: D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003975:Diazepam / Q000592:standards; D015658:HIV Infections / Q000097:blood / Q000188:drug therapy; D017320:HIV Protease Inhibitors / Q000097:blood / Q000627:therapeutic use; D006801:Humans; D061466:Lopinavir / Q000097:blood* / Q000627:therapeutic use; D012015:Reference Standards; D015203:Reproducibility of Results; D019438:Ritonavir / Q000097:blood* / Q000627:therapeutic use; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*
chemical_list: D017320:HIV Protease Inhibitors; D061466:Lopinavir; D019438:Ritonavir; D003975:Diazepam