title: The determination of total and unbound midazolam in human plasma. A comparison of high performance liquid chromatography, gas chromatography and gas chromatography/mass spectrometry.
abstract: Midazolam concentrations in patients' plasma was determined after extraction with high performance liquid chromatography (HPLC), gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). GC was selected for routine plasma assays in terms of selectivity, simplicity, precision, accuracy and sensitivity (0.02 microgram/mL); HPLC analysis was less sensitive (0.1 microgram/mL) than GC; GC/MS was used for analysis validation. Plasma protein binding of midazolam was determined by GC in patients' plasma after in vitro incubation with midazolam, ultrafiltration and extraction; 5% of the drug was unbound to plasma proteins. Midazolam distribution in lipoprotein fractions separated by ultracentrifugation of plasma obtained from patients on prolonged midazolam treatment was also assayed by GC.
authors.affiliation: Abteilung für Klinische Pharmakologie, Medizinische Klinik der Universität, Heidelberg, FRG.
authors.forename: J X
authors.initials: JX
authors.lastname: de Vries
authors.forename: J
authors.initials: J
authors.lastname: Rudi
authors.forename: I
authors.initials: I
authors.lastname: Walter-Sack
authors.forename: R
authors.initials: R
authors.lastname: Conradi
mesh_terms: D001798:Blood Proteins / Q000378:metabolism; D002849:Chromatography, Gas / Q000379:methods*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D008874:Midazolam / Q000097:blood*; D011485:Protein Binding
chemical_list: D001798:Blood Proteins; D008874:Midazolam