Simultaneous analysis of 1,2,3,4-tetrahydroisoquinolines by high-performance liquid chromatography using 4-(5,6-dimethoxy-2-phthalimidinyl)-2-methoxyphenylsulfonyl chloride as a fluorescent labeling reagent.
A highly sensitive high-performance liquid chromatographic method for the simultaneous analysis of 1,2,3,4-tetrahydroisoquinolines (TIQs) in the rat brain was developed. 1,2,3,4-Tetrahydroisoquinoline (TIQ), 1-methyl-1,2,3,4-tetrahydroisoquinoline (1-MeTIQ) and 1-benzyl-1,2,3,4-tetrahydroisoquinoline (1-BeTIQ) were derivatized with 4-(5,6-dimethoxy-2-phthalimidinyl)-2-methoxyphenylsulfonyl chloride to produce fluorescent sulfonamides. The labeling reaction was carried out at 50 degrees C for 15 min at pH 8.5. The fluorescent derivatives were separated on a reversed-phase column by gradient elution using (A) water-(B) acetonitrile/methanol (55:45) at 55 degrees C and detected by fluorescence measurement at 318 nm (excitation) and 398 nm (emission). The detection limits (signal-to-noise ratio=3) were 8-9 fmol per injection. The relative standard deviations (n=6) of TIQs were 2.6-10.5% and the recoveries were 87.6, 101.8 and 75.2%, respectively. The concentrations of TIQ, 1-MeTIQ and 1-BeTIQ in normal rat brains (n=6) were 0.7+/-0.3 (0.10+/-0.04), 3.4+/-1.5 (0.50+/-0.22) and 1.3+/-1.8 pmol/g (0.30+/-0.41 ng/g), respectively.
Inoue
Hirofumi
H
Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Fukuyama, Hiroshima 729-0292, Japan.
Matsubara
Daisuke
D
Tsuruta
Yasuto
Y
D000818:Animals; D001921:Brain / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry*; D008297:Male; D010797:Phthalimides / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods; D044005:Tetrahydroisoquinolines / Q000032:analysis*
C117624:4-(5,6-dimethoxy-2-phthalimidinyl)-2-methoxyphenylsulfonyl chloride; D005456:Fluorescent Dyes; D010797:Phthalimides; D044005:Tetrahydroisoquinolines; C014843:1,2,3,4-tetrahydroisoquinoline