Analysis of the second generation antidepressant venlafaxine and its main active metabolite O-desmethylvenlafaxine in human plasma by HPLC with spectrofluorimetric detection.
A high-performance liquid chromatographic method has been developed for the determination of the recent serotonin and norepinephrine reuptake inhibitor (SNRI) venlafaxine and its main active metabolite, O-desmethylvenlafaxine, in human plasma. Separation was obtained by using a reversed-phase column (C8, 150 x 4.6 mm I.D., 5 microm) and a mobile phase composed of 75% aqueous phosphate buffer containing triethylamine at pH 6.8 and 25% acetonitrile. Fluorescence detection was used, exciting at lambda=238 nm and monitoring the emission at lambda=300 nm. Citalopram was used as the internal standard. A careful pre-treatment of plasma samples was developed, using solid-phase extraction with C1 cartridges (100 mg, 1 mL). The limit of quantification (LOQ) was 1.0 ng mL(-1) and the limit of detection (LOD) was 0.3 ng mL(-1) for both analytes. The method was applied with success to plasma samples taken from patients undergoing treatment with venlafaxine. Precision data, as well as accuracy results, were satisfactory and no interference from other drugs was found. Hence, the method is suitable for therapeutic drug monitoring of venlafaxine and its main metabolite in depressed patients' plasma.
Mandrioli
Roberto
R
Pharmaco-Toxicological Analysis Laboratory, Department of Pharmaceutical Sciences, Faculty of Pharmacy, Alma Mater Studiorum, University of Bologna, Via Belmeloro 6, 40126 Bologna, Italy.
Mercolini
Laura
L
Cesta
Roberta
R
Fanali
Salvatore
S
Amore
Mario
M
Raggi
Maria Augusta
MA
D018687:Antidepressive Agents, Second-Generation / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003511:Cyclohexanols / Q000097:blood*; D000069468:Desvenlafaxine Succinate; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods*; D000069470:Venlafaxine Hydrochloride
D018687:Antidepressive Agents, Second-Generation; D003511:Cyclohexanols; D000069470:Venlafaxine Hydrochloride; D000069468:Desvenlafaxine Succinate