title: HPLC-MS method for the simultaneous quantification of the new HIV protease inhibitor darunavir, and 11 other antiretroviral agents in plasma of HIV-infected patients.
abstract: A new method using high performance liquid chromatography coupled with electrospray mass spectrometry (HPLC-MS) was developed and validated, for the quantification of plasma concentration of the new protease inhibitors darunavir (DRV) and other 11 antiretroviral agents (ritonavir, amprenavir, atazanavir, lopinavir, saquinavir, indinavir, nelfinavir and its metabolite M-8, nevirapine, efavirenz and tipranavir). A simple protein precipitation extraction procedure was applied on 50 microl of plasma aliquots and chromatographic separation of drugs and Internal Standard (quinoxaline) was achieved with a gradient (acetonitrile and water with formic acid 0.05%) on an C-18 reverse phase analytical column with 25 min of analytical run. Calibration curves were optimised according to expected ranges of drug concentrations in patients, and correlation coefficient (r2) was higher than 0.998 for all analytes. Mean intra- and inter-day precision (relative standard deviation %) for all compounds were 8.4 and 8.3%, respectively, and mean accuracy (% of deviation from nominal level) was 3.9%. Extraction recovery ranged within 93 and 105% for all drugs analysed. This novel HPLC-MS methodology allows a specific, sensitive and reliable determination of DRV and 11 other antiretrovirals. In our hand, it was used to measure DRV and ritonavir plasma concentration in HIV-positive patients, and it is now successfully applied for routine therapeutic drug monitoring and pharmacokinetics studies.
authors.affiliation: Department of Infectious Diseases, University of Torino, Amedeo di Savoia Hospital, Corso Svizzera 164, 10149 Turin, Italy. antodav@inwind.it
authors.forename: Antonio
authors.initials: A
authors.lastname: D'Avolio
authors.forename: Marco
authors.initials: M
authors.lastname: Siccardi
authors.forename: Mauro
authors.initials: M
authors.lastname: Sciandra
authors.forename: Lorena
authors.initials: L
authors.lastname: Baietto
authors.forename: Baietto
authors.initials: B
authors.lastname: Lorena
authors.forename: Stefano
authors.initials: S
authors.lastname: Bonora
authors.forename: Laura
authors.initials: L
authors.lastname: Trentini
authors.forename: Giovanni
authors.initials: G
authors.lastname: Di Perri
mesh_terms: D044966:Anti-Retroviral Agents / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D000069454:Darunavir; D004355:Drug Stability; D015658:HIV Infections / Q000097:blood*; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013449:Sulfonamides / Q000097:blood*
chemical_list: D044966:Anti-Retroviral Agents; D013449:Sulfonamides; D000069454:Darunavir