Dendrimer as nanocarrier for drug delivery

Dendrimers are novel three dimensional, hyperbranched globular nanopolymeric architectures. Attractive features like nanoscopic size, narrow polydispersity index, excellent control over molecular structure, availability of multiple functional groups at the periphery and cavities in the interior distinguish them amongst the available polymers. Applications of dendrimers in a large variety of fields have been explored. Drug delivery scientists are especially enthusiastic about possible utility of dendrimers as drug delivery tool. Terminal functionalities provide a platform for conjugation of the drug and targeting moieties. In addition, these peripheral functional groups can be employed to tailor-make the properties of dendrimers, enhancing their versatility. The present review highlights the contribution of dendrimers in the field of nanotechnology with intent to aid the researchers in exploring dendrimers in the field of drug delivery.     

我国医用聚氯乙烯增塑剂的发展现状

我国医用聚氯乙烯(PVC)以可致癌的邻苯二甲酸二辛酯(DOP)为主增塑剂,这严重影响了国内人民的健康和医用PVC行业的发展。通过对国内外各新型环保增塑剂的比较可知:无毒环保的乙酰柠檬酸三丁酯(ATBC)适合作为我国医用PVC制品的主增塑剂。这为改善医用PVC制品使用者的健康状态,加快医用环保PVC行业的发展提出了可行性。     

Chitosan—A versatile semi-synthetic polymer in biomedical applications

This review outlines the new developments on chitosan-based bioapplications. Over the last decade, functional biomaterials research has developed new drug delivery systems and improved scaffolds for regenerative medicine that is currently one of the most rapidly growing fields in the life sciences. The aim is to restore or replace damaged body parts or lost organs by transplanting supportive scaffolds with appropriate cells that in combination with biomolecules generate new tissue. This is a highly interdisciplinary field that encompasses polymer synthesis and modification, cell culturing, gene therapy, stem cell research, therapeutic cloning and tissue engineering. In this regard, chitosan, as a biopolymer derived macromolecular compound, has a major involvement. Chitosan is a polyelectrolyte with reactive functional groups, gel-forming capability, high adsorption capacity and biodegradability. In addition, it is innately biocompatible and non-toxic to living tissues as well as having antibacterial, antifungal and antitumor activity. These features highlight the suitability and extensive applications that chitosan has in medicine. Micro/nanoparticles and hydrogels are widely used in the design of chitosan-based therapeuticsystems. The chemical structure and relevant biological properties of chitosan for regenerative medicine have been summarized as well as the methods for the preparation of controlled drug release devices and their applications.     

气相色谱／质谱联用检测唇用产品中二甘醇的残留

建立了气相色谱／质谱联用（GC／MS）检测唇膏中二甘醇残留量的方法。样品经海砂研磨均匀、无水硫酸钠除水后,以甲醇超声提取,滤液直接检测。采用外标法,选择离子定量。二甘醇在10．0～1000．0mg／kg浓度范围内线性关系良好,相关系数（R2）为0．9994。在10～1000mg／kg添加水平的平均回收率为92．5％～106．9％,相对标准偏差（RSD）为3．5％～4．6％。实验表明,该方法适用于唇膏等化妆品中二甘醇残留量的检测。     

强酸型阳离子交换树脂催化剂预处理研究

本文分别采用静态和动态法对苯乙烯-二乙烯基苯强酸型阳离子交换树脂催化剂进行了预处理研究。结果表明在强酸型阳离子交换树脂催化剂中有5%～15%的磺酸基团属于快速流失部分, 经过预处理可以预先除去, 进而可提高催化剂的使用寿命。预处理后的树脂催化剂应用于丙烯水合反应。在140℃、8.0M Pa、丙烯空速 0.3h^-1、水烯摩尔比13.6 的反应条件下表现出很高的活性和稳定性。     

聚酯中二甘醇的影响因素及控制方法

讨论了影响切片中二甘醇含量的各种因素。对于聚酯生产中 ,二甘醇主要产生于第一酯化反应这一实际情况 ,提出要控制二甘醇的含量必须结合生产实际 ,及时调整n(EG) /n(PTA)、酯化温度、酯化压力、停留时间等。     

二甘醇合成吗啉的研究

对二甘醇和氨在催化剂存在及一定压力下反应制取吗啉的合成工艺路线、催化剂制备、产品分离及分析进行了详细综述.     

二乙二醇甲乙醚的合成及其合成条件优化

以二乙二醇单乙醚(DEGME)和氯甲烷为基本原料,氢氧化钠为催化剂、苯为带水剂,通过Williamson反应合成了二乙二醇甲乙醇(DEGMEE);用正效实验法对DEGMEE的合成条件进行了优化,气相色谱法分析了产品中DEGMEE的含量、FT IR和1H NMR法表征了产物结构。实验结果表明适宜的反应条件为:反应温度为60.0°C、醚化时间为4.0 h、n(CHCl)/n(DEGME)=1.15、n(NaOH)∶(DEGME)=1.30;在此条件下二乙二醇甲乙醚的收率可达93%以上。     

中纯度对苯二甲酸合成PET的工艺及性能研究

用中纯度对苯二甲酸(MTA)代替PTA合成PET,探讨了不同MTA含量对PET聚合反应及切片质 量的影响。表征了用MTA合成的PET的性能,并进行了可纺性试验。结果表明,用MTA替代PTA对PET 切片的黄色指数(b值)有一定的影响,但通过工艺配方的调整,加入80~100 mg/kg醋酸钴(调色剂)可改善 产品的色相,合成出性能优良的PET,切片的可纺性良好,其FDY质量指标和白度与常规切片FDY基本相 同。用MTA合成的PET结晶机理和常规PET相同,结晶速率高于常规PET,热稳定性略低于常规PET。     

氨纶废丝的醇解产物分析

以二甘醇为醇解剂,以二月桂酸二丁基锡为催化剂对氨纶废丝进行了醇解,醇解产物冷冻后分成两层,上层为白色蜡状醇解产物、下层为棕色液体。对白色蜡状醇解产物进行了红外光谱、核磁共振测试,对棕色液体进行了高效液相色谱—质谱联用测试。结果表明:白色蜡状醇解产物主要为聚醚多元醇;棕色液体除了过量的二甘醇以外,主要含有二甘醇-异氰酸酯加成化合物。