title: Development of an HPLC method for determining the alpha 2-adrenergic receptor agonist brimonidine in blood serum and aqueous humor of the eye.
abstract: A procedure for determining brimonidine [5-bromo-6-(2-imidazolidinylideneamino) quinoxaline] in biological samples using a reversed-phase isocratic HPLC method is described. The application in blood serum and eye aqueous humor of patients treated with the Alphagan ophthalmic solution was carried out by enrichment of samples in brimonidine with solid-phase liquid extraction. Brimonidine reached maximum levels in aqueous humor and serum within 2-2.5 h, whereafter a declining pattern was obtained. An approximate 50% level of brimonidine was identified in serum at 12 h after ocular administration, whereas in aqueous humor this percentage was determined after a period of 4-5 h.
authors: Department of Chemistry, University of Patras, Greece. karamanos@upatras.gr
authors: N K
authors: NK
authors: Karamanos
authors: F
authors: F
authors: Lamari
authors: J
authors: J
authors: Katsimpris
authors: S
authors: S
authors: Gartaganis
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000032:analysis / Q000097:blood*; D000368:Aged; D001082:Aqueous Humor / Q000737:chemistry*; D000068438:Brimonidine Tartrate; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D008297:Male; D011810:Quinoxalines / Q000032:analysis / Q000097:blood*; D018341:Receptors, Adrenergic, alpha-2 / Q000032:analysis / Q000097:blood*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000316:Adrenergic alpha-Agonists; D011810:Quinoxalines; D018341:Receptors, Adrenergic, alpha-2; D000068438:Brimonidine Tartrate