【作者】 刘佃森；

【导师】 沈青；

【作者基本信息】 东华大学 ， 材料物理与化学， 2006， 硕士

【摘要】 药物控制释放体系具有毒副作用低、疗效高、药效可控等优点,目前已经得到了广泛的临床应用,颇受人们关注。药物的释放速率取决于基材和药物的性质以及它们的结合方式,而外部环境（如温度、pH等）也有着举足轻重的影响。药物基材一般为高聚物,基材共混后的性质要发生变化,并出现单个高聚物本身不具备的某些性质。高聚物的相容性对共混物有着重要的影响。 通过研究可知:实验中制备的纤维素/PEG共混膜具有较好的相容性,其熵变值与纤维素的含量有关,随纤维素含量的增大而降低。由于相变材料可以进行调温控制,所以本课题在对共混膜的厚度加以控制的前提下,应用DSC方法估算了纤维素/聚乙二醇共混物的相变温度（Tr）,并研究了其与两组分比例之间的关系。结果显示:该共混物的Tr随纤维素比例增加而减小,且明显小于两个独立组分的Tr,其规律为:Tr=A-B*Ln(W_Cell/W_PEG)。式中A和B均为常数,W_Cell和W_PEG分别代表纤维素和聚乙二醇的重量,Ln为自然对数。 当纤维素/聚乙二醇的质量比为70/30时成膜性能最好,并且此时相变温度接近人体温度,有很大的医学价值。在此比例下以常用的维生素C和卡托普利为模型药物分别制备了两种药物膜;用电导率仪研究了含维生素C的药物膜在水中的缓释效果及动力学特征,不同的固液更多还原

【Abstract】 Controlled drug delivery systems (CDDS) offer numerous advantages compared to conventional dosage forms including improved efficacy, reduced toxicity and release can be controlled. The properties of polymer matrix and drug have an important effect on the drug release rate as well as their blending. The environment such as the temperature and pH will be affected to the release rate. We known that the drug matrix is polymer and their properties will change when they blending. The compatibility of polymer has an important effect on blending. There are often properties what the single polymer doesn’t possess.The cellulose/poly(ethylene glycol) membrane which prepared by the experiment have a good compatibility, their entropy change is related to the content of the cellulose and have inverse ratio to it. Phase change materials can control the temperature, so Applying DSC method to estimate the Tr for cellulose/poly(ethylene glycol) blend, results showed that this blend’s Tr is strongly influenced by the ratio of these two components, and this Tr was generally reduced with the increase of the cellulose percent in blend. According to DSC results, a model wasdeduced that might be available to describe above mentioned regulation between the ratio of two polymer components and blend’s Tr such as Tr=A-B*Ln(Wceii/WpEG). In eq., the symbols of WCeii and WPEG represent weight of cellulose and PEG respectively, "Ln" is the natural logarithm. "A" and "B " represent two constants respectively.The cellulose/poly(ethylene glycol)(PEG) blending membrane will have a highly value in medicine when their proportion is 70/30 in quality. By blending two common drugs, vitamin C and Captopril, with cellulose/poly(ethylene glycol) to prepare two drug membrane, and using electricity conductivity to study its drug release behavior and dynamics in vitro. At the same time this paper also study the release effect by the ratio of solid to liquid, pH and temperature, respectively.It can be found that the primary releasing reaction of the drug membrane is very complex during the drug releasing. At present the release pharmacodynamics models of blend drug membrane including one of the zero order, first order and second order equations, and there are many imaginary conditions in these models. As result, such models will bring bigger error and their limitations are obvious exist, they will not able to describe correctly the articulated behavior of the release phenomenon. So these models can’t reflect the release course accurately. In order to meet the need of the science and industry, it is necessary to obtain a model that could reflect the drug release course accurately andpracticably.This experiment used dynamic conductivity to study the drug release behavior in vitro and reported a new dynamic model. The model pointed out that the release of this drug membrane is zero order reaction mostly, at the same time there are first order and second order reaction. It can bedescribed as — = k0 + kxju + k2ju2, the symbols of k0 >. kx and￡2 dtrepresent the constant of zero ^ first and second order respectively. The constants are summarized in the paper. The advantages of the new model have no presumes and it including zero order, first order and second order. Though the membrane has bigger zero order releasing rate comparing to first order and second order, the new model hasn’t neglect others release. Appling multi-order release model to study drug release we can grasp the release rule macroscopically. This model offer us a multi-order release process and can be understood the release course accurately. At the same time, the releasing activation energy can be gained from the new model.LiuDiansenSupervised by Qing shen更多还原