Rapid and sensitive drug metabolism studies by SU-8 microchip capillary electrophoresis-electrospray ionization mass spectrometry.
J Chromatogr A
; 1218(5): 739-45, 2011 Feb 04.
Article
em En
| MEDLINE
| ID: mdl-21185563
ABSTRACT
Monolithically integrated, polymer (SU-8) microchips comprising an electrophoretic separation unit, a sheath flow interface, and an electrospray ionization (ESI) emitter were developed to improve the speed and throughput of metabolism research. Validation of the microchip method was performed using bufuralol 1-hydroxylation via CYP450 enzymes as the model reaction. The metabolite, 1-hydroxybufuralol, was easily separated from the substrate (R(s)=0.5) with very good detection sensitivity (LOD=9.3nM), linearity (range 50-500nM, r(2)=0.9997), and repeatability (RSD(Area)=10.3%, RSD(Migrationtime)=2.5% at 80nM concentration without internal standard). The kinetic parameters of bufuralol 1-hydroxylation determined by the microchip capillary electrophoresis (CE)-ESI/mass spectrometry (MS) method, were comparable to the values presented in literature as well as to the values determined by in-house liquid chromatography (LC)-UV. In addition to enzyme kinetics, metabolic profiling was demonstrated using authentic urine samples from healthy volunteers after intake of either tramadol or paracetamol. As a result, six metabolites of tramadol and four metabolites of paracetamol, including both phase I oxidation products and phase II conjugation products, were detected and separated from each other within 30-35s. Before analysis, the urine samples were pre-treated with on-chip, on-line liquid-phase microextraction (LPME) and the results were compared to those obtained from urine samples pre-treated with conventional C18 solid-phase extraction (SPE, off-chip cartridges). On the basis of our results, the SU-8 CE-ESI/MS microchips incorporating on-chip sample pre-treatment, injection, separation, and ESI/MS detection were proven as efficient and versatile tools for drug metabolism research.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Polímeros
/
Tramadol
/
Espectrometria de Massas por Ionização por Electrospray
/
Eletroforese em Microchip
/
Compostos de Epóxi
/
Etanolaminas
/
Acetaminofen
/
Modelos Químicos
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article