高分子材料在药物载体方面的研究进展

高分子载体药物是随着药物学研究、生物材料科学和临床医学的发展而新兴的给药技术。高分子材料作为药物的载体越来越多的被应用于化工医药领域,这一技术受到了研究者们的重视,并且得到了较好的发展。文章介绍近年来研究比较广泛的高分子药物载体的应用情况、有关机理以及制备方法。     

高分子药物载体的机理应用及展望

高分子药物载体是随着药物学研究、生物材料学和临床医学的发展而产生的一种新兴给药技术,随着高分子化学的不断发展,该技术越来越受到研究者们的高度重视。本文主要介绍了高分子药物载体的有关机理,应用情况,并展望了其发展前景。     

药物载体磁性高分子微球的制备及应用研究进展

介绍了药物载体磁性高分子微球的研究现状,总结了常用的制备方法及应用进展,展望了磁性高分子微球的发展前景。     

药用高分子材料的制备方法及应用

对药用高分子材料的用途及特点进行了概述,并且从高分子缓释药物载体、高分子药物、药物制剂和包装用高分子材料等3个方面叙述其制备方法及应用。     

药物缓释载体材料的研究进展

药物缓释载体材料是药物缓释系统的重要组成部分,药物缓释载体材料一般采用高分子材料,主要有天然高分子及合成高分子材料两种。常用的天然高分子材料有海藻酸盐、壳聚糖、明胶、蛋白(胶原、白蛋白)等。常用的合成高分子材料有聚乳酸、聚酯类、高聚物水凝胶类、互穿网络聚合物(IPN)材料等。文章对目前研究的热点的药物缓释载体材料进行了介绍。     

壳聚糖基纳米药物载体研究进展

壳聚糖作为天然高分子多糖,已被认为是一种极具希望的高分子药物跨膜运输载体,而壳聚糖基纳米微粒是主要的载体形式之一。本文综述了壳聚糖基纳米药物载体的制备方法及几种主要纳米载体形式在药物运输中的应用研究进展。     

高分子在医药领域的应用

较为详细地论述了高分子材料在药用辅料、生物制药、药物载体、基因载体中的应用现状，展望了新医用高分子材料对医药高新技术发展的推动。     

基于合成高分子的纳米药物载体的研究进展

基于合成高分子的纳米微粒由于其良好的生物相容性、生物可降解性和粘膜粘附性等特点成为药物载体研究的热．董。根据构建纳米药物载体的高分子聚合物结构的差异,将其分为：基于两亲聚合物的纳米微粒（胶团和囊泡）、脂质体、树枝状或超支化大分子、乳液聚合纳米微粒,并对上述纳米微粒作为药物载体在近年来的研究进展进行了归纳和总结．展望了其在药物缓释体系中的广阔应用前景。     

高分子药物

<正> 现在用来治病的药物,不论是人工合成的或是天然的,大多是小分子的化合物。应用高分子作成药物,则是本世纪六十年代后期才开始兴起的。高分子药物大致可概括为两种类型:一种是高分子本身就具有药理作用的;一类是把小分子药物结合到高分子载体上制成,即把小分子药物以共价键或离子键的形式接到高分子载体上,也可将小分子药物包封在高分子材料做成的基质中,使之微胶囊化。这样     

高分子缓、控释材料的研究进展

高分子缓、控释材料因其原材料来源广泛、复合改性能力强、受环境影响因素多而成为调节药物释放载体材料的研究重点,极具发展前景。分类祥述了各种药用高分子缓释材料与控释材料以及它们的性能特点和应用,并简明介绍了药用高分子缓、控释材料的研究价值与动向。     

基于壳聚糖的缓释材料应用研究进展

药物缓释材料种类繁多,壳聚糖因其自身多方面的特性而成为理想的药物缓释载体。文章简要介绍了壳聚糖的缓释机理,且因壳聚糖本身拥有的特殊药理作用,它可用于抗炎、抗癌、抗肺结核及基因类药物载体,模型实验显示均收到了较好的药物缓释效果和相应的治疗效果,因此,本文主要介绍了壳聚糖作为不同药物缓释载体的应用研究进展。     

Cogrinding as an approach to enhance dissolution rate of a poorly water-soluble drug (gliclazide)

Gliclazide is practically insoluble in water. In order to improve the drug dissolution rate, cogrinding method was used as an approach to prepare gliclazide coground/solid dispersions (SDs) in the carriers such as povidone (PVP-K30), crospovidone and microcrystalline cellulose (Avicel PH 101) with different drug to carrier ratios. The dissolution rate of gliclazide from the SDs was measured at two physiological pH values of 1.2 and 7.2 simulating gastric and intestinal fluids using USP dissolution apparatus II. The concentration of the dissolved drug in the medium was determined by direct or first-derivative UV spectroscopy. The dissolution rates of the formulations were dependent on the nature and ratio of drug to carriers in SDs and the corresponding physical mixtures as well as the pH of the medium. At a higher pH the drug has a faster dissolution than at a lower pH. The fastest dissolution rates were observed from coground formulations with the drug to carrier ratio of 1:5. The amount of drug dissolved in 15 min from these SDs was varied from 96% in the case of Avicel SD to 100% for SD of PVP. Whereas the amount of drug released in the same time from unground drug powder (UD), ground drug powder (GD) and all physical mixtures was between 60 and 80%. These results indicate that the dissolution rate is highly enhanced from the SDs. DSC as well as X-ray diffraction showed reduced drug crystallinity in SDs. Scanning electron microscopy and particle size analysis revealed significant decreased particle size of the drug in SDs. FT-IR spectroscopy demonstrated no detectable interactions between the drug and carriers. In addition to latter evidence, increased wettability and hydrophilicity of drug particles and deaggregation brought about by the carriers are the reasons for enhanced drug dissolution from the SDs. One of the possible advantages of formulating an insoluble drug such as gliclazide is that if it is used in preparation of capsules or tablets of the drug, its dose might be reduced which is economically beneficial.     

Nanotechnology for Topical Drug Delivery to the Anterior Segment of the Eye

Topical drug delivery is one of the most challenging aspects of eye therapy. Eye drops are the most prevalent drug form, especially for widely distributed anterior segment eye diseases (cataracts, glaucoma, dry eye syndrome, inflammatory diseases, etc.), because they are convenient and easy to apply by patients. However, conventional drug formulations are usually characterized by short retention time in the tear film, insufficient contact with epithelium, fast elimination, and difficulties in overcoming ocular tissue barriers. Not more than 5% of the total drug dose administered in eye drops reaches the interior ocular tissues. To overcome the ocular drug delivery barriers and improve drug bioavailability, various conventional and novel drug delivery systems have been developed. Among these, nanosize carriers are the most attractive. The review is focused on the different drug carriers, such as synthetic and natural polymers, as well as inorganic carriers, with special attention to nanoparticles and nanomicelles. Studies in vitro and in vivo have demonstrated that new formulations could help to improve the bioavailability of the drugs, provide sustained drug release, enhance and prolong their therapeutic action. Promising results were obtained with drug-loaded nanoparticles included in in situ gel.     

TiO2纳米结构作为载体在药物缓控释传递系统的应用

TiO₂纳米结构以其生物相容性好、机械强度高、耐热耐腐蚀等优点,在药物缓控释传递系统载体应用方面引起广泛关注。结合近几年研究报道,本文将单一和功能化TiO₂纳米结构作为药物缓控释载体进行分类,简述了制备方法、结构表征、载药方法、释药机理等,分析了功能化TiO₂纳米结构修饰结合外界刺激响应在药物缓控释系统的应用。结果表明,相比单一结构,功能化修饰后的TiO₂纳米结构具有载药率高、缓控释效果明显、生物相容性好等优点;功能化修饰结合外界刺激响应,进一步提升药物缓控释效果;而相比单一和双重刺激响应,多重刺激响应能够更好地实现局部靶向释药。最后预测该纳米结构作为药物缓控释传递系统载体的研究发展方向并指出目前实现临床应用所面临的问题。     

聚氨酯用作抗癌药物载体的研究进展

将聚氨酯抗癌药物载体分为靶向输送型、敏感释药型和增强摄取型3种类型,介绍了在抗癌药物载体领域聚氨酯的研究现状,展望了其研究前景。     

Pancreatic Ductal Cell-Derived Extracellular Vesicles Are Effective Drug Carriers to Enhance Paclitaxel’s Efficacy in Pancreatic Cancer Cells through Clathrin-Mediated Endocytosis

Chemo-resistance challenges the clinical management of pancreatic ductal adenocarcinoma (PDAC). A limited admittance of chemotherapeutics to PDAC tissues is a key obstacle in chemotherapy of the malignancy. An enhanced uptake of drugs into PDAC cells is required for a more effective treatment. Extracellular vesicles (EVs), especially small EVs (sEVs), have emerged as drug carriers for delivering chemotherapeutics due to their low immunogenicity and propensity for homing toward tumor cells. The present study evaluated sEVs derived from six different human cell lines as carriers for paclitaxel (PTX). The encapsulation of the chemotherapeutics was achieved using incubation, sonication and electroporation. The cytotoxicity of the EV drugs was evaluated by MTS assay. While sonication led to a higher efficiency of drug loading than incubation and electroporation, PTX loaded through incubation with HPNE-derived sEVs (HI-PTX) was the most efficacious in killing PDAC cells. Furthermore, HI-PTX was taken up by PDAC cells more efficiently than other EV drugs, implying that the efficacy of HI-PTX is associated with its efficient uptake. This was supported by the observation that the cytotoxicity and uptake of HI-PTX is mediated via the clathrin-dependent endocytosis. Our results indicate that the hTERT-HPNE cell-derived EVs are effective drug carriers to enhance paclitaxel’s efficacy in PDAC cells.     

Study on modification of NH2-MCM-41 and its pH-responsive drug release

Mesoporous silica (MCM-41) was synthesized by copolycondensation of tetraethoxysilane (TEOS) and 3-aminopropyltriethoxysilane (APTES). Firstly, it was modified with amino group. Then, four different drug carriers, Me-Ph-NH-MCM-41, OHC-Ph-NH-MCM-41, HO-Ph-NH-MCM-41, and HOOC-Ph-NH-MCM-41, were synthesized by grafting —R group (—R: —CHO, —OH, —CH₃, —COOH), respectively. FT-IR, SEM, Zeta potential, and XRD were used to characterize its structure and morphology, indicating the successful synthesis of modified MCM-41. Rhodamine B (RhB) was used as a model for drug loading performance testing and the sensitive drug release behavior of this drug release system under different pH simulated humors was investigated. The effects of different —R groups on drug release were also explored. The results show that the four carriers hardly release drugs under neutral conditions. The drug release can be effectively controlled by changing the pH of the environmental system. The drug release behavior can be described by the Korsmeyer-Peppas kinetic model. The experiment showed that the drug release amount: RhB@HOOC-Ph-NH-MCM-41>RhB@OHC-Ph-NH-MCM-41>RhB@HO-Ph-NH-MCM-41>RhB@Me-Ph-NH-MCM-41. The pH-response of drug carriers with different —R groups was different, and the drug release amount of RhB@HOOC-Ph-NH-MCM-41 reached 57.87% at pH = 1.2, which has some potential applications in intelligent controlled release materials of drugs.     

Macromolecular Conjugates of 4- and 8-Aminoquinoline Compounds

Some members of 4-aminoquinolines and 8-aminoquinolines have been found to provide adjuvant effects when used in combination with anti-cancer drugs. The clinical co-administration of active anti-cancer drugs with other drugs acting as potentiating agents has shown considerable merits when compared to a single-drug administration. Anti-cancer drugs are often toxic when delivered straight, but the bio-reversible drug conjugation of anticancer drugs to water-soluble macromolecular carriers has proved to enhance the therapeutic effectiveness of anticancer drugs. Following facilitated pharmacokinetics pathways, the conjugates, acting as pro-drugs, will release the active drug species in the transformed target cells and their designs are geared towards reducing pharmacological barriers of toxicity, drug resistance and poor bioavailability encountered with currently used anti-cancer drugs. This paper describes the synthesis of water-soluble macromolecular carriers containing 4- and 8-aminoquinolines that are bio-reversibly anchored with cytotoxic drugs. The conjugates and co-conjugates are isolated as water soluble solids and characterized by NMR-spectroscopy.     

NH2-MCM-41的改性及其pH响应性释药的研究

采用正硅酸乙酯（TEOS）和3-氨丙基三乙氧基硅烷（APTES）通过共缩聚法合成介孔二氧化硅（MCM-41）。首先对其氨基修饰,再通过有机合成接枝—R基团（—R：—CHO、—OH、—CH₃、—COOH）,制备得到Me-Ph-NH-MCM-41、OHC-Ph-NH-MCM-41、HO-Ph-NH-MCM-41、HOOC-Ph-NH-MCM-41四种不同的药物载体。利用FT-IR、Zeta电位、XRD和SEM对其结构和形貌表征,结果表明NH₂-MCM-41改性成功。以罗丹明B（RhB）为模型进行载药性能测试,并考察了此释药系统在模拟不同pH的体液下的敏感释药行为,同时探究了不同—R基团对释药的影响。结果显示,四种载体在中性条件下几乎不发生药物释放,通过改变环境体系pH可以有效控制药物释放,其释药行为可以用Korsmeyer-Peppas动力学模型来描述。实验表明,释药量：RhB@HOOC-Ph-NH-MCM-41>RhB@OHC-Ph-NH-MCM-41>RhB@HO-Ph-NH-MCM-41>RhB@Me-Ph-NH-MCM-41,不同—R基团的药物载体的pH响应性不同,其中RhB@HOOC-Ph-NH-MCM-41释药量在pH=1.2时可达57.87%,在用于药物智能控释材料方面具有一定的应用潜力。