基于脂质前药的自组装药物传递系统

综述了脂质前药及自组装药物传递系统.药质体是基于脂质前药的自组装药物传递系统之一,对其概念、特点、制备方法和潜在应用性进行了简要介绍.     

小分子自组装纳米递药系统研究进展

生物纳米技术在药物递送领域的应用为高端创新制剂的研发注入了新动力,一系列新型纳米递药系统被相继开发乃至应用于临床。其中,由小分子药物或前药自组装形成的纳米递药系统因具有制备工艺简便、载药量超高和易于实现工业化生产等优势而备受关注,已成为纳米递药系统领域的一个重要分支。本文总结了小分子自组装纳米递药系统的最新研究进展。首先,对小分子前药自组装纳米递药系统进行介绍,包括两亲性、疏水性和二聚体小分子前药自组装纳米递药系统。其次,分别介绍小分子化学药物和小分子生物药物自组装纳米递药系统的最新进展。再者,对小分子杂化共组装纳米递药系统进行总结和分析,包括小分子纯药共组装纳米递药系统、小分子前药共组装纳米递药系统及小分子前药/小分子纯药共组装纳米递药系统。最后,讨论了小分子自组装纳米递药系统的合理设计、应用前景和临床挑战,以期为新一代纳米制剂的设计与构建提供参考。     

抗结核药物新剂型-异烟肼药质体的研究

药质体是基于脂质前药的自组装药物传递系统之一，它作为一种新的药物传递技术，载药量大、稳定性好、有靶向性和控释性。抗结核药物异烟肼制备成药质体能靶向巨噬细胞，提高药物渗透性。本文对药质体概念、特性、目前研究状况和异烟肼制备成药质体前景进行综述。     

齐多夫定脂质前药自组装体的制备及其在大鼠血浆中的稳定性

目的制备齐多夫定脂质前药自组装体,考察其在大鼠血浆中的稳定性。方法用乙醇注入法制备齐多夫定脂质前药自组装体,透射电子显微镜和激光粒度测定仪观测其形态和粒度,高效液相色谱法测定齐多夫定脂质前药自组装体在大鼠血浆中降解情况。结果齐多夫定脂质前药自组装体是球形囊泡,平均粒径为200nm;在大鼠血浆中降解半衰期为3.68h,降解产物为齐多夫定。结论齐多夫定脂质前药自组装体在体外生物环境中能较快地降解出原药。     

川陈皮素自组装前体脂质体的制备及其大鼠体内药代动力学研究

本文研制川陈皮素自组装前体脂质体, 并以混悬剂为对照考察其经大鼠灌胃给药后的药代动力学行为。采用一种新型前体脂质体法制备川陈皮素自组装前体脂质体, 考察其水合后粒径、包封率和稳定性等理化性质; 大鼠分别灌胃给予川陈皮素混悬剂和水合后的脂质体, 以尼莫地平为内标, 采用HPLC法测定血浆中药物浓度, 用Kinatica 4.4程序计算药代动力学参数。制得的川陈皮素前体脂质体经水合后包封率可达80%以上,平均粒径为212.1 nm, 稳定性好; 药代动力学研究显示,与混悬剂相比川陈皮素脂质体在体内吸收较快, 相对生物利用度为264.3%, MRT增加。结果表明, 川陈皮素自组装前体脂质体制备工艺简单可行; 川陈皮素制成自组装前体脂质体后, 大鼠口服吸收显著增加。     

分子动力学模拟技术在自组装纳米递药系统研究中的应用进展

分子动力学模拟技术是一种依靠牛顿力学模拟分子体系的运动来研究现实系统的计算机模拟方法,近年来逐渐被用于自组装纳米递药系统的自组装过程揭示及宏观性能预测,有助于高效率、精准化设计制剂。本综述从分子动力学模拟技术的定义、类型及操作流程出发,总结了其在自组装纳米递药体系研究中的应用,包括自组装过程微观信息(尺寸形貌、微区组成、分子分布)的获取与分析、宏观性能(稳定性、载药能力、释药性及跨膜性能)的预测,并对其在递药系统处方预测中的应用进行了归纳,同时展望了未来实现制剂处方预测的策略,旨在为制剂研究人员选择适宜的路径研究纳米体系提供理论依据,为分子动力学模拟技术在制剂领域更广阔的应用提供参考。     

薯蓣皂苷元衍生物双药自组装纳米给药系统的构建及质量评价

目的:构建药辅同源双药自组装纳米给药系统,并对其进行质量评价。方法:以薯蓣皂苷元(diosgenin,DG)为原料,设计、合成具有两亲性的DG衍生物(DGG),运用¹H-NMR、¹³C-NMR和HR-MS对其结构进行确证;稳态荧光法测定临界聚集浓度;将DGG和二十二碳六烯酸(docosahexaenoic acid,DHA)等比混合,采用纳米沉淀法制备DGG/DHA(DD NPs)双药自组装纳米给药系统,以粒径和PDI值为指标对处方进行单因素考查并优化,通过透射电镜、激光粒径仪对纳米粒的形态、粒径及分布进行表征,并对其稳定性、包封率、载药量和溶血性进行评价。结果:DD NPs双药自组装纳米粒的平均粒径为(164.1±3.9) nm,载药量为(63.24±0.39)%,储存稳定性良好;实验表明,DD NPs在酸性条件下有一定的溶血性。结论:DD NPs形成稳定性良好、粒径小、载药量高的类球状双药纳米给药系统,为DG和DHA协同抗肿瘤研究和应用奠定了基础。     

自微乳释药系统研究进展

简要介绍了自微乳释药系统的组成、体外释药研究方法及自微乳新型制剂的研究进展.自微乳新型制剂主要包括固体自微乳、过饱和自微乳和正电荷自微乳,新型自微乳制剂可以弥补其不足,更好地发挥自微乳固有特点.     

壳聚糖-磷脂自组装纳米粒载药系统的研究进展

本文综述了壳聚糖-磷脂自组装纳米粒作为新型药物递送系统的研究进展,阐述其自组装过程的关键机制,揭示了所得纳米粒独特的核-壳结构及该结构与包载药物之间的相互作用关系;总结了相关制备方法,并对经典的溶剂滴入法进行了详细说明.在此基础上,全面归纳了壳聚糖-磷脂自组装纳米粒在递送抗肿瘤药、抗炎药、多肽类药物、降脂药、抗菌药及基...     

川陈皮素自组装前体脂质体大鼠在体肠吸收研究

目的 考察川陈皮素自组装前体脂质体在大鼠肠道的吸收情况。方法 以川陈皮素溶液、普通脂质体为对照,采用单向灌流法,研究不同肠段川陈皮素自组装前体脂质体的大鼠肠道吸收动力学。结果 3种制剂在全肠段都有吸收,在各个肠段,3种制剂的净累积吸收量、Ka和Peff均表现为川陈皮素自组装前体脂质体>川陈皮素普通脂质体>川陈皮素(P<0.05)。结论 川陈皮素自组装前体脂质体可显著促进川陈皮素的口服吸收。     

Prodrugs for transdermal drug delivery – trends and challenges

Prodrugs continue to attract significant interest in the transdermal drug delivery field. These moieties can confer favorable physicochemical properties on transdermal drug delivery candidates. Alkyl chain lengthening, pegylation are some of the strategies used for prodrug synthesis. It is usually important to optimize partition coefficient, water and oil solubilities of drugs. In this review, progress made in the field of prodrugs for percutaneous penetration is highlighted and the challenges discussed.     

硅纳米管药物传递系统研究进展

综述了近年来国内外硅纳米管药物传递系统的研究进展,包括硅纳米管的特点、制备工艺、功能化及用作药物传递系统的研究情况。硅纳米管具有内部空腔体积大、表面积大、生物相容性好及表面可功能化等特点,能克服一般药物传递系统所存在的载药量较小、药物易发生泄漏等缺陷,是一种极具开发潜力的新型药物传递系统。     

Ophthalmic drug delivery systems

New ophthalmic drug delivery systems are curently receiving increased attention, in part because of the expected emergence of new drugs with short biological half-lives whose usefulness may depend on a more continuous drug supply than eyedrops can provide, but also because of the potential of some delivery systems to reduce the side effects of the more potent drugs recently introduced or presently under investigation. Some ophthalmic delivery systems extend the duration of drug action by enhancement of corneal absorption; these systems include soluble gels and emulsions, hydrophilic ocular inserts, ion-pair associations, prodrugs, and liposomes. Since these systems enhance the “pulse entry” of the drug, they are limited to use with drugs whose dose-related side effects are not serious. Other delivery systems provide for a controlled release of drugs and therefore minimize the pulse entry with which side effects are associated. They can be based on any of several different mechanisms and include both erodible and nonerodible matrices. The various delivery systems that have recently been developed and those that are currently known to be under investigation are described in this paper, along with some observations regarding the future outlook of ophthalmic drug delivery systems.     

Colonic Drug Delivery: Prodrug Approach

The colon is largely being investigated as a site for administration of protein and peptides, which are degraded by digestive enzymes in the upper GIT. Also for local diseases of the colon, drug administration to the site of action can not only reduce the dose to be administered, but also decrease the side effects. One of the approaches used for colon specific drug delivery is the formation of a prodrug which optimizes drug delivery and improves drug efficacy. Many prodrugs have been evaluated for colon drug delivery. These prodrugs are designed to pass intact and unabsorbed from the upper GIT and undergo biotransformation in the colon releasing the active drug molecule. This biotransformation is carried out by a variety of enzymes, mainly of bacterial origin present in the colon (e.g. azoreductase, glucuronidase, glycosidase, dextranase, esterase, nitroreductase, cyclodextranase, etc.). The present review includes varius prodrug approaches investigated for colon drug delivery and their site specificity.     

自微乳释药系统及其制剂的研究进展

根据近期报道的自微乳释药系统最新研究进展,详细阐述自微乳释药系统的特点、性质、机制、处方工艺和质量评价,并介绍了有代表性的自微乳制剂。自微乳释药系统能显著增加某些药物的吸收和生物利用度,在药学领域将有很好的应用前景。     

眼部的给药屏障和给药途径

近年来,眼部药物递送系统越来越受到重视,本文综述了目前眼部给药的主要屏障包括角膜、结膜屏障,血房水屏障、血视网膜屏障等,以及一些新的给药途径和给药方法如结膜下、巩膜给药和离子电渗疗法等。以环孢素A为例介绍了一些克服眼部屏障的给药方法。尽管眼部给药系统目前已取得了进展,但药物递送到眼的后段仍有较大的难度,需要进一步开发更有效的眼部药物递送系统。     

肝靶向给药系统的研究进展

通过对近年来国内外报道的肝靶向研究相关文献进行检索,根据肝靶向药物的不同作用机制对肝靶向给药系统的研究进展进行分析和总结。有关肝靶向药物的研究结果表明,肝靶向给药系统能选择性地将药物输送至肝脏病变部位,通过提高其在肝脏病变组织的药物浓度,从而达到增强药物疗效、减少其毒副作用的目的。因此,肝靶向给药系统在肝脏疾病治疗方面具有广阔的应用前景。     

Self-assembled drug delivery systems 2. Cholesteryl derivatives of antiviral nucleoside analogues: synthesis, properties and the vesicle formation

Self-assembled drug delivery systems (SADDS) are defined as the self-aggregates of amphiphilic prodrugs. Prodrug, molecular self-assembly and nanotechnology are involved in SADDS manufacturing. But the knowledge of the self-assembly of amphiphilic prodrugs and the formation rules of SADDS is very limited. In this paper, five cholesteryl derivatives of antiviral nucleoside analogues were synthesized, involving antiviral acyclovir, didanosine and zidovudine, and the different acyl linkers, succinyl, adipoyl and phosphoryl. The derivatives are typical amphiphiles with nucleosides as polar heads and long-chained lipids as hydrophobic tails. The derivatives showed the similar soluble behavior, and the solubility highly depended on the types of solvents. Two forces, hydrogen bonding and hydrophobic interaction in alcohol solutions could improve the derivatives dissolving. However, the molecular self-assembly of derivatives could prefer to happen in the noncompetitive solvents including chloroform and tetrahydrofuran (THF) based on the intermolecular hydrogen bonding between nucleobase moieties, which could greatly increase their solubility. The derivatives formed nanosized vesicles based on hydrophobic interaction after injecting their THF solutions into water. The volume ratios of polar heads and hydrophobic tails of amphiphiles could determine the vesicle size, and the amphiphiles with large ratios would prefer to form small vesicles. The self-assembled vesicles would likely become SADDS.     

Microbial esterases and ester prodrugs: An unlikely marriage for combating antibiotic resistance

The rise of antibiotic resistance necessitates the search for new platforms for drug development. Prodrugs are common tools for overcoming drawbacks typically associated with drug formulation and delivery, with ester prodrugs providing a classic strategy for masking polar alcohol and carboxylic acid functionalities and improving cell permeability. Ester prodrugs are normally designed to have simple ester groups, as they are expected to be cleaved and reactivated by a wide spectrum of cellular esterases. However, a number of pathogenic and commensal microbial esterases have been found to possess significant substrate specificity and can play an unexpected role in drug metabolism. Ester protection can also introduce antimicrobial properties into previously nontoxic drugs through alterations in cell permeability or solubility. Finally, mutation to microbial esterases is a novel mechanism for the development of antibiotic resistance. In this review, we highlight the important pathogenic and xenobiotic functions of microbial esterases and discuss the development and application of ester prodrugs for targeting microbial infections and combating antibiotic resistance. Esterases are often overlooked as therapeutic targets. Yet, with the growing need to develop new antibiotics, a thorough understanding of the specificity and function of microbial esterases and their combined action with ester prodrug antibiotics will support the design of future therapeutics.