不同溶解性质的药物在O/W微乳中的溶解度和体外释放特征  

Solubilities and in vitro Release in Microemulsions of Drugs Distinguished by Their Dissolvabilities

作　　者：胡海燕[1,2] 徐雄良[1] 龚涛[1] 王荣昌[2] 张志荣[1] 

机构地区：[1]四川大学华西药学院 [2]中山大学药学院,广州510080

出　　处：《中国药学杂志》2006年第9期678-682,共5页Chinese Pharmaceutical Journal

基　　金：国家自然科学基金(30430770)

摘　　要：目的探讨不同溶解性质的药物在O/W微乳中的溶解机制及体外释放特征。方法制备喷昔洛韦、布洛芬,阿克拉霉素O/W型微乳,并对微乳形态及大小进行表征；测定药物在微乳及在微乳组分中的溶解度,进行比较分析。用平衡透析法考察载药微乳的体外释放。结果电镜及光子分光光度法均显示空白微乳与载药微乳粒径均为20 nm左右。药物在微乳中的溶解度与药物在外相、内相及总表面活性剂中的溶解度的总和相当。喷昔洛韦在微乳外相的溶解度较大,体外释放速率较快；布洛芬、阿克拉霉素在微乳内相及总表面活性剂的溶解度较大,体外释放速率较慢。结论微乳对药物的增溶作用与药物在油相,水相及总表面活性剂中的溶解度相关；微乳对药物的释放,特别是对脂溶性药物的释放有明显的延缓作用。OBJECTIVE To study the solttbilizing mechanisms of drugs in O/W microemulsions and release characteristics of various drug-loaded O/W mieroemulsions in vitro. METHODS Penciclovir-loaded, ibuprofen-loaded and aclarinomylin-loaded microemusions （PCV-MEs, IBU-MEs, ACM-MEs） were prepared, and their shape and droplet sizes were observed. The solubilities of drugs in the microemulsion and in the components of microemulsion were determined. To obtain the accumulative release percentage of drugs, the in vitro release of drug-loaded microemulsions was investigated by equilibrium dialysis method. RESULTS The droplet sizes of all microemulsions, including drug-free and drug-loaded, were about 20 nm. The solubilities of drugs in microemulsions were tightly related to their .solubilities in compenents of microemulsions and were close to the sum of solubilities in the total surfactants （ Stot）, the oil phase and the aqueous phase. All drug-loaded microemulsion showed sustained-release in the release, medium compared with drug solutions, and decreased release was observed when oil and Stot contents in micmemulsions were increased . PCV-MEs showed quicker release than IBU-MEs and ACM-MEs did, which was likely due to high solubilization of penciclovir in the outer aqueous phase while ibuprofen and aelarinomylin in internal oil phase and surfacrants. During the release test, drugs disposed on the interfacial film and in the internal phase were released into the medium by diffusing aeross intertacial structure so as to prolong the release time in vitro. CONCLUSION The solubilization of microemulsions on drugs is tightly related to their components and can be, estimated by the sum solubilities of the drug in Stot, the oil phase and the aqueous phase. Being a hopeful drug carriers, microemulsions can delay the release of drugs, especially of lipophilic drugs.

关 键 词：喷昔洛韦 布洛芬 阿克拉霉素 微乳 溶解度 体外释放 

分 类 号：R943.4[医药卫生—药剂学]