Study on expression of luminescence function of short life-excited molecules in bioluminescence

为了提供对超氧阴离子具有高化学发光强度和高特异性的化学发光探针，合成并表征了环糊精与荧光素共价结合to6-(4-methoxyphenyl)imidazo[1，2-a]pyrazin-3(7H)-one的新型化学发光探针。利用次黄嘌呤-黄嘌呤氧化酶体系产生超氧阴离子，这些新型化学发光探针显示出比6-[4-[2-[N-(5-fluoresceinyl)thioureido]-ethoxy]phenyl]-2-methylimidazo[1，2-a]pyrazin-3(7H)-one(FCLA).更强的超氧诱导化学发光强度当探针浓度为1.0 mM时，6-(4-methoxyphenyl)imidazo[1，2-a]pyrazin-3(7H)-one和荧光素分别共价连接在γ-环糊精的仲羟基面和伯羟基面上的化合物的绿色发光强度是FCLA的26倍，这也是本研究中最高的发光强度。当探针浓度小于1.0 mM时，该化合物的超氧化物依赖化学发光强度与背景化学发光强度之比高于FCLA。这些高的超氧诱导化学发光强度和低探针浓度下的超氧化物专一性表明，该化合物可以比FCLA更有效地测量超氧阴离子。

In providing chemiluminescent probes that have high chemiluminescence intensity and high specificity to superoxide anions, novel chemiluminescent probes involving cyclodextrins covalently bound to6-(4-methoxyphenyl)imidazo[1,2-a]pyrazin-3(7H)-one with fluorescein were synthesized and characterized. Using the hypoxanthine-xanthine oxidase system for the generation of the superoxide anions, these novel chemiluminescent probes showed higher superoxide-induced chemiluminescence intensity than that of 6-[4-[2-[N-(5-fluoresceinyl)thioureido]-ethoxy]phenyl]-2-methylimidazo[1,2-a]pyrazin-3(7H)-one(FCLA). When tested at a probe concentration of 1.0mM, compound, in which 6-(4-methoxyphenyl)imidazo[1,2-a]pyrazin-3(7H)-one and fluorescein are covalently attached on the secondary and primary hydroxyl faces of γ-cyclodextrin, respectively, showed green-luminescence intensity that was 26 times that of FCLA, which was also the highest luminescence intensity in this present study. At probe concentrations of less than 1.0mM, the ratio of the superoxide-dependent chemiluminescence intensity to the background chemiluminescence intensity for the compound was higher than that of FCLA. These high superoxide-induced chemiluminescence intensity and superoxide-specificity n low probe concentrations indicates that the compound can be more effective than FCLA towards the measurement of superoxide anions.