Determination of lopinavir and nevirapine by high-performance liquid chromatography after solid-phase extraction: application for the assessment of their transplacental passage at delivery.
J Chromatogr B Analyt Technol Biomed Life Sci
; 774(2): 127-40, 2002 Jul 15.
Article
em En
| MEDLINE
| ID: mdl-12076682
ABSTRACT
An adaptation of the HPLC method previously described for the simultaneous assay of amprenavir, ritonavir, indinavir, saquinavir, nelfinavir and efavirenz after solid-phase extraction is proposed here for the separate analysis of the newer PI lopinavir (LPV) and the NNRTI nevirapine (NVP). After viral inactivation by heat (60 degrees C for 60 min), plasma (600 microl), with clozapine added as internal standard, is diluted 1+1 with phosphate buffer pH 7 and subjected to a solid-phase extraction on a C(18) cartridge. Matrix components are eliminated with 2 x 500 microl of a solution of 0.1% H(3)PO(4) neutralised with NaOH to pH 7. LPV and NVP are eluted with 3 x 500 microl MeOH. The resulting eluate is evaporated under nitrogen at room temperature and is reconstituted in 100 microl MeOH 50%. A 40-microl volume is injected onto a Nucleosil 100, 5 microm C(18) AB column. LPV and NVP are analysed separately using a gradient elution program with solvents constituted of MeCN and phosphate buffer adjusted to pH 5.07 and containing 0.02% sodium heptanesulfonate. LPV and NVP are detected by UV at 201 and 282 nm, respectively. The calibration curves are linear up to 10 microg/ml. The mean absolute recovery of LPV and NVP is 91% and 88%, respectively. The method is precise with mean inter-day C.V.s within 2.1-6.6% and 0.9-1.7% for LPV and NVP, and accurate (range of inter-day deviations -1.1 to +2.4%, and -1.9 to +0.8%, for LPV and NVP, respectively). The method has been validated and is currently applied to the monitoring of LPV and NVP in HIV patients, and has been notably applied in a study aimed at assessing the extent of transplacental passage of nevirapine and PIs, notably lopinavir, at the time of delivery in pregnant HIV-infected women.
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Base de dados:
MEDLINE
Assunto principal:
Pirimidinonas
/
Cromatografia Líquida de Alta Pressão
/
Inibidores da Protease de HIV
/
Inibidores da Transcriptase Reversa
/
Nevirapina
/
Troca Materno-Fetal
Tipo de estudo:
Diagnostic_studies
Limite:
Female
/
Humans
/
Pregnancy
Idioma:
En
Ano de publicação:
2002
Tipo de documento:
Article