title: Determination by coupled high-performance liquid chromatography-gas chromatography of the beta-blocker levomoprolol in plasma following ophthalmic administration.
abstract: Levomoprolol is a beta-blocking agent used in the topical treatment of glaucoma. The necessity for comparing the plasma levels of a drug administered by the ophthalmic route with those obtained following systemic treatment requires increasingly sensitive methods in order to determine the low plasma concentrations produced by the administration of eye drops. On-line high-performance liquid chromatography-gas chromatography and concurrent solvent evaporation proved to be advantageous in the determination of levomoprolol in human plasma. Levomoprolol was determined by capillary gas chromatography (GC) with electron-capture detection (ECD) after solid-phase extraction from plasma and derivatization. Quantitation was based on the internal standard method. The detection limit of 0.2 ng/ml is 50 times lower than that obtained with previous GC methods involving on-column injection and ECD.
authors.affiliation: R&D Laboratories, Inpharzam Ricerche S.A. (Zambon Group), Cadempino, Switzerland.
authors.forename: V
authors.initials: V
authors.lastname: Gianesello
authors.forename: E
authors.initials: E
authors.lastname: Brenn
authors.forename: G
authors.initials: G
authors.lastname: Figini
authors.forename: A
authors.initials: A
authors.lastname: Gazzaniga
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000097:blood*; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D009883:Ophthalmic Solutions; D050198:Phenoxypropanolamines; D011412:Propanolamines / Q000008:administration & dosage / Q000097:blood*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000319:Adrenergic beta-Antagonists; D009883:Ophthalmic Solutions; D050198:Phenoxypropanolamines; D011412:Propanolamines; C009976:moprolol