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.     

微乳色谱应用研究进展

微乳(Microemulsion,ME)是由乳化剂、助乳化剂、油相和水相组成的光学上各向同性,热力学稳定的液-液分散体[1],只要组分的比例合适即可自发形成均匀透明或微呈乳光的体系并保持稳定。以微乳为流动相进行的色谱称为微乳色谱[2]。微乳色谱近年来得到广泛研究和应用,其中微乳电动色谱的研究应用较多。本文简单介绍微乳的色谱行为,并就近年来微乳色谱的应用研究进展进行综述,主要介绍微乳电动色谱、微乳液相色谱、微乳薄层色谱、微乳毛细管电泳。1微乳的色谱行为微乳体系中由于引入表面活性剂,其亲水亲油性使得较大范围极性的物质都能在微乳中…     

药用微乳处方设计概述

综述了影响药用微乳处方设计的各种因素，介绍了药用微乳的形成机制、组成成分、制备方法、微乳结构的检测技术及计算机辅助微乳处方设计的探索。     

油酸微乳对利多卡因透皮吸收的影响

目的研究油酸微乳对利多卡因透皮吸收的影响。方法在制备相图的基础上，考察了微乳的组分对微乳形成的影响。选择适当的表面活性剂/助表面活性剂比例，制备利多卡因的油酸微乳处方，考察微乳、乳剂、胶束和饱和水溶液在透皮吸收方面的差异。结果以Labrasol为表面活性剂，吐温80为助表面活性剂所得油酸微乳的区域较大，微乳对利多卡因有明显的促透作用，透皮速率依次为微乳＞乳剂＞饱和水溶液＞胶束。结论油酸微乳可促进利多卡因的透皮吸收。     

不同链长油相对葛根素微乳经淋巴转运吸收的影响

目的：以实验室前期研究得到的微乳处方为基础,采用乳糜微粒阻断法研究微乳处方中不同链长度油相对葛根素微乳经淋巴转运的影响。方法：采用乳糜微粒阻滞技术阻断药物淋巴转运,高效液相色谱法测定大鼠血浆中葛根素浓度,比较阻断组与未阻断组生物利用度来计算淋巴转运的比例。结果：长链油微乳的淋巴转运比例为49.7%,中链油微乳、及短链油微乳为29.8%、22.5%。长链油微乳的淋巴转运比例高于中链油微乳及短链油微乳,且其生物利用度也高于中链油微乳及短链油微乳,差异具有统计学意义。结论：长链油微乳更能促进葛根素经肠道吸收,增加其在血浆中的浓度,从而提高生物利用度。     

天然乳化剂阿拉伯胶对绿原酸自微乳体内外性能的影响

目的:研究天然乳化剂阿拉伯胶对绿原酸自微乳体内外性能的影响。方法:以阿拉伯胶逐步取代含非离子型乳化剂的绿原酸自微乳(简称"传统绿原酸自微乳")中的聚山梨酯80制成含阿拉伯胶的绿原酸自微乳(简称"新型绿原酸自微乳"),评价两种自微乳的外观、乳滴形态、粒径、电导率、p H值、稳定性、体外释放度和肠吸收动力学指标。结果:新型绿原酸自微乳采用阿拉伯胶取代了聚山梨酯80处方量的50%。传统和新型绿原酸自微乳的微乳液外观澄明,乳滴为近似球形,粒径分别为(24.53±3.03)、(35.51±5.91)nm,电导率分别为(195.6±0.3)、(189.5±0.4)μs/cm,p H分别为3.87±0.02、4.08±0.03(n=3)。与传统绿原酸自微乳比较,新型绿原酸自微乳在十二指肠、空肠、回肠中的吸收速率常数、有效渗透系数和吸收量均略有增加(P>0.05),在结肠中的上述指标均明显降低(P<0.05)。结论:新型绿原酸自微乳可保持传统绿原酸自微乳的性能,并能增加绿原酸在小肠的吸收。     

白藜芦醇微乳的制备及表征

目的:采用高压均质法制备白藜芦醇微乳,并对其进行表征。方法:以白藜芦醇微乳粒径分布、多分散系数(Pd I)、包封率为评价指标,考察制备白藜芦醇微乳的各个因素,并对制得的微乳进行表征;初步研究白藜芦醇微乳的稳定性。结果:白藜芦醇微乳的平均粒径为231±37.8 nm,Pd I为0.228±0.047,zeta电位为-42.5±4.3 m V;透射电镜显示微乳粒径均一,成球状分布。长期稳定性研究显示,微乳在25℃条件下放置3个月稳定。结论:高压均质法制备白藜芦醇微乳工艺简单易行。     

阿托伐他汀自微乳释药系统的制备和评价

目的制备阿托伐他汀自微乳，为自微乳释药系统的处方设计和体内外评价提供参考。方法采用伪三元相图法研究不同乳化剂、助乳化剂和油相形成微乳的能力和区域，绘制不同处方组成的相图，在此基础上制备阿托伐他汀自微乳，比较温度、介质、稀释等因素对自微乳效率的影响，进行自微乳时间、所成微乳的形态、粒径分布、zeta电位、含量和稳定性等体外评价Beagle犬体内药代动力学研究。结果理想的处方经分散后可得到平均粒径在100 nm以下、呈高斯分布的微乳，稳定性好，自微乳效率高，在Beagle犬体内的吸收明显高于市售片剂。结论本文首次研制阿托伐他汀自微乳，稳定性好，在Beagle犬体内的生物利用度高。     

含天然乳化剂的盐酸小檗碱自微乳的制备与体内外性能评价

目的:制备含阿拉伯胶的盐酸小檗碱自微乳,考察其体内外性能。方法:以天然乳化剂阿拉伯胶部分代替合成非离子型乳化剂聚山梨酯80制备盐酸小檗碱自微乳;评价两种自微乳的自乳化速率、微乳形态、粒径分布和释放度;采用大鼠在体单向肠灌流模型对两种自微乳的吸收动力学进行体内评价。结果:与合成乳化剂自微乳相比,天然乳化剂自微乳的自乳化速率基本相同,微乳乳滴粒径及粒径分布范围有所变大,体外释放速度略有降低,对盐酸小檗碱在大鼠在体肠吸收的促进效果更好。结论:用天然乳化剂阿拉伯胶部分代替合成乳化剂所制备的盐酸小檗碱自微乳可保持自微乳原有的体内外行为。     

苦参碱口服微乳的制备及含量测定

目的制备苦参碱口服微乳,并对微乳进行含量测定和理化性质考察。方法通过滴定法绘制伪三元相图,考察不同因素对微乳区域的影响,筛选合适的微乳处方;采用稀释法和染色法鉴别微乳的类型。结果确定了油酸乙酯-cremophor EL-无水乙醇-蒸馏水的苦参碱微乳,所制备微乳为O/W型;理化性质:pH值为8.23、平均粒径为61.3 nm、黏度为0.022 mPa.s、电导率为0.183 2 S.m-1z、eta电位为-3.72 mV;HPLC法测定微乳中苦参碱的平均质量浓度为39.94 g.L-1。结论所制备的苦参碱微乳粒径较小,分布均匀,理化性质稳定,为进一步研究奠定了基础。     

脉冲释药系统的新进展

综述近年来脉冲释药系统的新进展。脉冲释药系统是一种按照生理节律设计、定时定量脉冲式释放有效治疗量药物的剂型。根据剂型设计原理和药物释药机制,将脉冲释药系统分为预设药物传递系统、闭环反馈型传递系统和开环传递系统三大类。     

Intraoral drug delivery

The oral availability of many drugs is poor because of the pH of the stomach, the presence of enzymes, and extensive first-pass metabolism. Traditionally, these drugs have been administered as parenteral drug delivery systems, which invariably leads to poor patient compliance. This has made the pharmaceutical industry look for alternative routes of drug delivery. One possible route is via the oral cavity. This review compares the many different and novel drug delivery systems that have been developed for absorption through the oral cavity as well as those that undergo quick disintegration or dissolution in the oral cavity. Systems for oral delivery include mucoadhesive patches, films and tablets, as well as quick-disintegrating wafers, tablets and films. There are many examples of drugs that have been formulated into intraoral absorptive drug delivery systems as well as quick-disintegrating drug delivery systems. The fact that most of the research being conducted on intraoral drug delivery systems is driven by pharmaceutical manufacturers demonstrates the need for such drug delivery systems. As we begin to discover more about oral mucosal drug delivery, and develop much more sophisticated drug delivery systems, many more drugs will be formulated as intraoral systems. There is no doubt that the need for these systems is real, and many classes of drugs could benefit from this noninvasive type of drug delivery. The challenge now is to synthesize drug moieties that exhibit increased absorption across the oral mucosa and are more potent in their action. Intraoral drug delivery systems are possibly one of the very few drug delivery systems that seem to be ahead of the development of new drug compounds that are effectively absorbed across tissue membranes.     

RNA药物非病毒递送系统研究进展

RNA疗法通过将外源性的RNA引入特定细胞来调控基因表达,是一种非常有潜力的疾病治疗策略。然而,由于存在体内稳定性差、难以高效进入靶细胞等问题,RNA药物的递送需借助合适的药物递送系统。与病毒载体相比,非病毒载体具有更高的安全性,已成为本领域的研究热点。主要介绍脂质纳米颗粒递送系统、生物偶联递送系统以及外泌体递送系统这3种可帮助RNA疗法进入临床的非病毒载体递送系统,并对其技术进展和难点进行分析与总结。     

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.     

胃滞留给药系统的研究进展及其在中药制剂中的应用

在口服制剂中,胃滞留给药系统可以延长药物在胃内的滞留时间,进而延长其在整个胃肠道的转运时间,增加药物的吸收,从而提高临床疗效,因此它是一种理想的给药系统。本文通过查阅国内外文献进行归纳,从胃滞留给药系统的影响因素、分类、制剂研究（包括中药胃滞留制剂）及上市产品进展等方面对近年来胃滞留制剂的研究进展进行综述。     

Approaches to neural tissue engineering using scaffolds for drug delivery

This review seeks to give an overview of the current approaches to drug delivery from scaffolds for neural tissue engineering applications. The challenges presented by attempting to replicate the three types of nervous tissue (brain, spinal cord, and peripheral nerve) are summarized. Potential scaffold materials (both synthetic and natural) and target drugs are discussed with the benefits and drawbacks given. Finally, common methods of drug delivery, including degradable/diffusion-based delivery systems, affinity-based delivery systems, immobilized drug delivery systems, and electrically controlled drug delivery systems, are examined and critiqued. Based on the current body of work, suggestions for future directions of research in the field of neural tissue engineering are presented.     

Pharmaceutical aspects of intranasal delivery of vaccines using particulate systems

The nasal route offers a promising opportunity for the delivery of vaccines. This review analyses the opportunities and novel delivery strategies based on particulate systems for the nasal delivery of vaccines, including liposomes, proteosomes, virosomes, nano- and microparticulate systems, with and without adjuvants. The influence of pharmaceutical aspects of the particulate formulations on nasal delivery is analysed. Recently developed delivery devices for nasal vaccination are also described. Potential barriers to clinical and commercial success of some novel intranasal vaccines are critically evaluated. Although particulate systems may offer potential in the nasal delivery of vaccines by enhancing uptake by antigen-presenting cells, the real success in enhancement of vaccine delivery can only be achieved by careful design and manipulation of physicochemical properties of particulate vaccine delivery systems.     

Drug delivery systems for differential release in combination therapy

INTRODUCTION: Combination therapy with multiple therapeutic agents has wide applicability in medical and surgical treatment, especially in the treatment of cancer. Thus, new drug delivery systems that can differentially release two or more drugs are desired. Utilizing new techniques to engineer the established drug delivery systems and synthesizing new materials and designing carriers with new structures are feasible ways to fabricate proper multi-agent delivery systems, which are critical to meet requirements in the clinic and improve therapeutic efficacy. AREAS COVERED: This paper aims to give an overview about the multi-agent delivery systems developed in the last decade for differential release in combination therapy. Multi-agent delivery systems from nanoscale to bulk scale, such as liposomes, micelles, polymer conjugates, nano/microparticles and hydrogels, developed over the last 10 years, have been collected and summarized. The characteristics of different delivery systems are described and discussed, including the structure of drug carriers, drug-loading techniques, release behaviors and consequent evaluation in biological assays. EXPERT OPINION: The chemical structure of drug delivery systems is the key to controlling the release of therapeutic agents in combination therapy, and the differential release of multiple drugs could be realized by the successful design of a proper delivery system. Besides biological evaluation in vitro and in vivo, it is important to speed up practical application of the resulting delivery systems.     

Drug delivery from the oral cavity: focus on a novel mechatronic delivery device

Dental drug delivery systems have been used for a long time, in particular for the local therapy of diseases affecting the oral cavity. Research today concentrates on the design of formulations to increase their retention time. Even today, however, prosthetic devices incorporating drug delivery are rarely used. Mainly, they are focused on prophylaxis and the release of antibacterial agents. However, as buccal delivery, because of its undeniable advantages, has become popular for systemic drug delivery, and prolonged well-controlled release has been identified as beneficial, especially for chronic diseases, a new class of delivery systems is evolving: highly miniaturized computerized delivery systems, integrated into a dental appliance. Dental delivery systems today are used in two ways: the main application is the local treatment of diseases affecting the oral cavity itself like periodontitis or fungal infections. The second is for systemic drug delivery.     

Past and future evolution in colloidal drug delivery systems

Colloidal drug delivery systems have been providing alternative formulation approaches for problematic drug candidates, and improved delivery for existing compounds for decades. Colloidal systems for drug delivery have all evolved down a similar pathway, almost irrespective of the delivery system, from conception, to the use of safer excipients, PEGylation for passive targeting and attachment of ligands for active targeting. The recent emergence of truly biologically interactive systems represents the latest step forward in colloidal delivery systems. In this article, the maturation pathway and recent advances for the major classes of colloidal delivery systems are reviewed, and the paper poses the question of whether the nanotechnology boom will create a revolution in colloidal delivery, or just the next natural stage in evolution.