荧光光谱法考察β-环糊精-洛伐他汀包合性能

Study on the Properties of Inclusion Complex ofβ-Cyclodextrin and Lovastatin by Spectrofluorimetry

采用荧光光谱法进行β-环糊精(β-cyclodextrin,β-CD)、洛伐他汀(Lovastatin,也称莫那克林K:Monacolin K,MK)包合物的荧光光谱特征,对包合体系的影响因素缓冲液体积温度、时间、β-CD浓度作相应考察;通过共沉淀法制备了β-CD-MK包合物,并通过高效液相法和荧光光谱增强法作了表征分析。结果表明,荧光检测时最佳发射波长EX=225 nm,激发波长EM=333 nm。β-CD-MK的包合过程是以物质的量比1∶1的形式形成,由Benesi-Hildebrand的双倒数法求得包合常数K=538.50 L/mol(25℃),进而求得包合过程中的其他热力学常数。该反应为放热自发过程。鉴于在包合体系过程中环糊精的加入能显著提高MK的荧光值,一个简单、快速以及高灵敏度测定MK含量的方法被开发,对比传统的高效液相法,两者的方法学考察RSD均≤5%。

Spectrofluorimetry was used to analyze the features of the inclusion complex ofβ-cyclodextrin and lovastatin.The factors influencing the inclusion system,including buffer volume,temperature,time andβ-CD-MK concentration,were analyzed.β-CD-MK inclusion complex was prepared by coprecipitation and characterized by HPLC and fluorescence enhancement.The results showed that the optimal emission wavelength was 225 nm and the excitation wavelength was 333 nm.Theβ-CD-MK inclusion complex was formed with the mass ratio of 1∶1,and the inclusion constant K was 538.50 L/mol(25℃).The inclusion constant was obtained by the double inverse method of Benesi-Hildebrand,and then other thermodynamic constants of the inclusion process were obtained.The reaction was an exothermic spontaneous process.In view of the fact that the addition of cyclodextrin in the inclusion system could significantly improve the fluorescence value of MK,a simple,fast and highly sensitive method for the determination of MK content was developed.Compared with the traditional HPLC method,the RSD of both methods was less than 5%.