2'-Deoxyguanosineのメチル化剤処理により生成するO6-methyldeoxyguanosineのケイ光-高速液体クロマトグラフィーによる定量

High-performance liquid chromatographic determination of O6-methylguanine (MeGua) was studied using phenacyl bromide as a precolumn derivatization reagent. After the selective condensation of O6-MeGua to form fluorescent 9-methoxy-6-phenylimidazo [2, 1-b] purine (phenyletheno-O6-MeGua), separation of that compound from guanine and 7-methylguanine was achieved on an ODS column (150 mm×4 mm i. d.) with acetonitrile-50 mM ammonium dihydrogenphosphate solution containing 5 mM Na 1-octanesulfonate (25 : 75), and the separated etheno-O6-MeGua derivatives was detected with a fluorescence monitor (319 nm for excitation and 404 nm for emission). O6-MeGua can be detected as phenyletheno-O6-MeGua by a fluorometric detector at a level of 40 pg (signal/noise=2). 2'-Deoxyguanosine (dGuo) was reacted with various methylating agents to furnish O6-methyldeoxyguanosine (MedGuo). Then, O6-MeGua, which is given from O6-MedGuo by acid hydrolysis, was determined by the fluorometric derivatization.