title: A reliable method to quantify sildenafil and its metabolite N-demethylsildenafil by HPLC in plasma of children.
abstract: The aim of this study was to develop a simple method for quantifying plasma levels of sildenafil and its metabolite by liquid chromatography with a C18 reverse-phase column and UV detection. For both compounds, linearity was assessed in the range from 10 and 1 000 ng · ml-1 and had correlation coefficients of r=0.995 and r=0.997 for sildenafil and its metabolite, respectively. The inter- and intra-day coefficients of variation was<5.3%. The limits of detection and quantification were 1 and 10 ng · ml-1. Drug levels were determined satisfactorily in two patients. A simple and reliable method was developed for use in children with Pulmonary Arterial Hypertension under treatment with sildenafil.
authors.affiliation: Laboratorio de Farmacología, Instituto Nacional de Pediatría, Mexico City, Mexico.
authors.forename: B
authors.initials: B
authors.lastname: Ramírez-Mendiola
authors.forename: C
authors.initials: C
authors.lastname: Flores-Pérez
authors.forename: R
authors.initials: R
authors.lastname: García-Álvarez
authors.forename: H
authors.initials: H
authors.lastname: Juárez-Olguín
authors.forename: J
authors.initials: J
authors.lastname: Flores-Pérez
authors.forename: J L
authors.initials: JL
authors.lastname: Chávez Pacheco
mesh_terms: D002648:Child; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D058986:Phosphodiesterase 5 Inhibitors / Q000097:blood*; D010879:Piperazines / Q000097:blood*; D011687:Purines / Q000097:blood; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000097:blood*
chemical_list: D058986:Phosphodiesterase 5 Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate