Abstract: Five newly synthesized Ntetrahydrobenzothiazolyl imines show weak chemiluminescence(CL) when oxidized by Ce(Ⅳ) in sulfuric acid, which is significantly enhanced when quinine is present as sensitizer.The possible mechanism is proposed based on CLspectrum, fluorescent spectrum and absorbent spectrum of Schiff base.The relationship between the CLintensity and the concentration of Schiff base is linear in the range of2.0×10^-7-8.0×10^-5mol/L, and the detection limit is8.0×10^-8mol/L.The relative standard deviation(RSD) for₇independent determinations of2.0×10^-6mol/L Schiff base is 2.4%. Common excipient starch was used in pharmaceutical preparation and most of metal ions do not interfere with the determination of Schiff base, except Mn(Ⅱ), Fe(Ⅲ), Fe(Ⅱ), Bi(Ⅲ), Ti(Ⅰ).The method has been successfully used in analysis of synthesized samples

Key words: Chemiluninescence, Cerium(Ⅳ), Quinine, N-Tetrahydrobenzothiazolyl imine, Folw injection analysis