title: Rapid LC-MS drug metabolite profiling using microsomal enzyme bioreactors in a parallel processing format.
abstract: Silica nanoparticle bioreactors featuring thin films of enzymes and polyions were utilized in a novel high-throughput 96-well plate format for drug metabolism profiling. The utility of the approach was illustrated by investigating the metabolism of the drugs diclofenac (DCF), troglitazone (TGZ), and raloxifene, for which we observed known metabolic oxidation and bioconjugation pathways and turnover rates. A broad range of enzymes was included by utilizing human liver (HLM), rat liver (RLM) and bicistronic human-cyt P450 3A4 (bicis.-3A4) microsomes as enzyme sources. This parallel approach significantly shortens sample preparation steps compared to an earlier manual processing with nanoparticle bioreactors, allowing a range of significant enzyme reactions to be processed simultaneously. Enzyme turnover rates using the microsomal bioreactors were 2-3 fold larger compared to using conventional microsomal dispersions, most likely because of better accessibility of the enzymes. Ketoconazole (KET) and quinidine (QIN), substrates specific to cyt P450 3A enzymes, were used to demonstrate applicability to establish potentially toxic drug-drug interactions involving enzyme inhibition and acceleration.
authors.affiliation: Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060, USA.
authors.forename: Besnik
authors.initials: B
authors.lastname: Bajrami
authors.forename: Linlin
authors.initials: L
authors.lastname: Zhao
authors.forename: John B
authors.initials: JB
authors.lastname: Schenkman
authors.forename: James F
authors.initials: JF
authors.lastname: Rusling
mesh_terms: D000818:Animals; D019149:Bioreactors; D002839:Chromans / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D002853:Chromatography, Liquid; D051544:Cytochrome P-450 CYP3A / Q000737:chemistry / Q000378:metabolism*; D065692:Cytochrome P-450 CYP3A Inhibitors; D004008:Diclofenac / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D007654:Ketoconazole / Q000494:pharmacology; D013058:Mass Spectrometry; D008862:Microsomes, Liver / Q000201:enzymology*; D053758:Nanoparticles / Q000737:chemistry; D011802:Quinidine / Q000494:pharmacology; D020849:Raloxifene Hydrochloride / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D051381:Rats; D012822:Silicon Dioxide / Q000737:chemistry; D045162:Thiazolidinediones / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D000077288:Troglitazone
chemical_list: D002839:Chromans; D065692:Cytochrome P-450 CYP3A Inhibitors; D045162:Thiazolidinediones; D004008:Diclofenac; D020849:Raloxifene Hydrochloride; D012822:Silicon Dioxide; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human; D000077288:Troglitazone; D011802:Quinidine; D007654:Ketoconazole