极谱法研究辅酶Q_(10)与β-环糊精的包结行为

Inclusion of coenzyme Q_(10) with β-cyclodextrin studied by polarography

目的研究辅酶Q10与β-环糊精(-βCD)的包结行为。方法用极谱法考察主体分子-βCD与电活性客体分子辅酶Q10发生包结反应时,包结物还原波峰电流随时间的变化,峰电位随-βCD浓度的变化,并在自然光照条件下分别考察辅酶Q10和包结物的还原波峰电流随时间的变化。结果在0.1 mol.L-1HAc/NaAc(pH 4.7)的乙醇-水(60∶40)介质中,辅酶Q10与β-CD形成1∶1的包结物,测得其包结常数Kf为1.26×104L.mol-1,包结反应的表观速率常数k为6.64×10-2m in-1。并测得辅酶Q10的光降解表观速率常数k为7.77×10-3m in-1,辅酶Q10--βCD包结物的k为3.38×10-3m in-1。结论辅酶Q10和-βCD可形成包结物,并在一定程度上提高了辅酶Q10的光稳定性。

Aim To investigate the inclusion of coenzyme Q10 with β-cyclodextrin （β-CD）. Methods The inclusion of the electroactive guest molecule coenzyme Q10 with the host molecule β-CD was studied by the polarography. The change of the reduction peak current of the inclusion complex with time and the change of the peak potential of the inclusion complex with β-CD concentration were examined. In order to study the photostability, the change of the reduction peak current of both coenzyme Q10 and coenzyme Q10- β-CD inclusion complex with time were also examined under light, separately. Results In 0. 1 mol · L^-1 HAc/NaAc （pH 4.7） buffer-ethanol/water （60： 40） medium, coenzyme Q10 was included with β-CD to form an 1 ： 1 inclusion complex. The formation constant Kf was 1.26×10^4L·mol-1, the apparent formation rate constant was 6.64×10^-2 min^-1.The photodegradation apparent rate constant of coenzyme Q10 was 7.77×10^-3 min^ -1, and that of the coenzyme Q10-β-CD inclusion complex was 3.38 × 10^-3 min^-1 Conclusion The inclusion of coenzyme Q10 with β-CD took place. The stability of coenzyme Q10 to lights was improved in a certain degree due to the formation of the inclusion complex.