极谱法研究辅酶Q10与β-环糊精的包结行为

目的研究辅酶Q_{10与β-环糊精(β-CD)的包结行为。方法用极谱法考察主体分子β-CD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β-CD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^-1 HAc/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1.26×10⁴ L·mol^-1，包结反应的表观速率常数k为6.64×10^-2 min^-1。并测得辅酶Q10的光降解表观速率常数k为7.77×10^-3 min^-1，辅酶Q10-β-CD包结物的k为3.38×10^-3 min^-1。结论辅酶Q10和β-CD可形成包结物，并在一定程度上提高了辅酶Q10的光稳定性。}

Inclusion of coenzyme Q10 with β-cyclodextrin studied by polarography

AimTo 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. ResultsIn 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 k_f was 1.26×10⁴ L·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. ConclusionThe 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.