title: Optimization of a rapid capillary electrophoresis ESI-IT tandem mass spectrometry method for the analysis of short-chain carnitines in human plasma.
abstract: A capillary electrophoresis (CE) method coupled to electrospray ionization ion trap tandem mass spectrometry (ESI-IT-MS/MS) is described for the rapid analysis of carnitine, acetylcarnitine, and propionylcarnitine in human plasma. Optimization of the procedure was achieved by a reduced sample pretreatment and after examining several physicochemical parameters that influence both the CE separation and the MS analytes detection. The analysis of total carnitine in human plasma after hydrolysis of short-chain metabolites is also shown. The analysis of carnitine and metabolites was obtained in less than 10 min using a 200 mM ammonium formate buffer, pH 2.5, with high sensitivity and specificity using the MS detection in product ion scan mode. The method was tested for quantitative recovery using dialyzed human plasma as matrix and showed linearity in the concentrations ranges 20-160, 1-32, and 0.25-8 microM for carnitine, acetylcarnitine, and propionylcarnitine with (squared) correlation coefficients of 0.9984, 0.9995, and 0.9991, respectively. The intraday and intermediate analysis repeatability and accuracy are within 15% of relative standard deviation (RSD) at low, medium, and high concentration and within/or slight exceeding 20% at the lower limit of quantitation (LLOQ). The method is sensitive for determining carnitine and its metabolites in human plasma with high specificity.
authors.affiliation: Istituto di Chimica del Riconoscimento Molecolare-Sez di Roma, Consiglio Nazionale delle Ricerche, c/o dell'Università Cattolica del Sacro Cuore, L.go F. Vito 1, 00168, Roma, Italy. claudia.desiderio@icrm.cnr.it
authors.forename: Claudia
authors.initials: C
authors.lastname: Desiderio
authors.forename: Antonella
authors.initials: A
authors.lastname: De Rossi
authors.forename: Rosanna
authors.initials: R
authors.lastname: Inzitari
authors.forename: Angelo
authors.initials: A
authors.lastname: Mancinelli
authors.forename: Diana Valeria
authors.initials: DV
authors.lastname: Rossetti
authors.forename: Massimo
authors.initials: M
authors.lastname: Castagnola
authors.forename: Irene
authors.initials: I
authors.lastname: Messana
mesh_terms: D002331:Carnitine / Q000097:blood* / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D006801:Humans; D015394:Molecular Structure; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013997:Time Factors
chemical_list: D002331:Carnitine