标题：Simultaneous Determination of Oxidized and Reduced Coenzyme Q and α-Tocopherol in Biological Samples by High Performance Liquid Chromatography with Platinum Catalyst Reduction and Electrochemical Detection
摘要：A convenient and sensitive high performance liquid chromatographic method with post-column platinum catalyst reduction and electrochemical detection was applied to the simultaneous determination of oxidized and reduced coenzyme Q (CoQ and CoQH2) and α-tocopherol (α-TP) in human and rat samples. After the separation of oxidized and reduced CoQ homologues (CoQ8-CoQ10 and CoQ8H2-CoQ10H2) and α-TP on a reversed-phase column, oxidized CoQ homologues were reduced on a platinum catalyst reduction column, and then all the reduced forms were quantified with an electrochemical detector operated in the oxidation mode (+0.6V vs. Ag/AgCl). The order of elution was α-TP, CoQ8H2, CoQ9H2, CoQ8, CoQ10H2, CoQ9, and CoQ10 and all were well separated within 13min. The detection limits at a signal-to-noise ratio of 3 were 20pg for α-TP, 70pg for CoQ8 and CoQ8H2, and 100pg for CoQ9, CoQ9H2, CoQ10 and CoQ10H2. Quantitative recoveries (93-102%) from serum and tissues were obtained for all the analytes studied. This method was applied satisfactorily to the simultaneous determination of CoQ, CoQH2 and α-TP in biological materials.
