避蚊胺-海藻酸钙微球的试制

采用溶剂挥发法制备避蚊胺-海藻酸钙微球。所得微球外观圆整,平均粒径47.2μm,载药量（26.33±1.17）%,包封率（87.41±3.21）%。考察了将其加至空白霜剂后对大鼠离体皮肤累积渗透量的影响,并与微粉硅胶载药霜剂和原药霜剂比较。结果表明,海藻酸钙微球可减少避蚊胺的累积渗透量。     

双氯芬酸钠海藻酸钙凝胶微球的制备及其性质分析

目的制备双氯芬酸钠海藻酸钙凝胶微球，并对凝胶微球的性质进行分析。方法采用滴制法制备双氯芬酸钠海藻酸钙凝胶微球，紫外分光光度法测定药物的含量，对凝胶微球的粒度、圆整度、休止角和堆密度进行测定，并用扫描电镜观察凝胶微球的形态。结果制备的双氯芬酸钠海藻酸钙凝胶微球包封率较高，粉体学性质良好，球形均匀圆整。结论该方法适用于双氯芬酸钠海藻酸钙凝胶微球的制备。     

海藻酸钙凝胶微球的制备和pH依赖性溶胀

利用海藻酸钠溶液与氯化钙溶液发生胶凝反应，本文用滴制的方法制备了海藻酸钙凝胶微球，并对制备的处方和工艺进行了探讨，同时考察了海藻酸钙凝胶微球的特征和溶胀特性。干燥的凝胶微球在不同pH的水性介质中溶胀特性不同。海藻酸钙凝胶微球的这种溶胀的pH敏感性，使其能成为口服药物缓释制剂的载体。     

叶酸-多聚糖复合物海藻酸钙肺靶向微球处方工艺的优化

用单因素考察和均匀设计筛选叶酸-多聚糖复合物肺靶向海藻酸钙微球的最佳处方工艺;考察了微球的体外释药特性和稳定性.按最佳工艺制得的微球形态圆整,粒径在5～20μm范围内,分散性好,体外累积释放率-时间方程为1-Q=0.2941e-0.0331t 0.2820e-0.00085t(r=-0.9905),微球临界相对湿度为72%,存放在4℃和25℃条件下稳定.     

多柔比星海藻酸钙微球的制备及其载药、释药性质的研究

目的：考察多柔比星海藻酸钙微球的制备工艺及载药、释药性质。方法：考察不同处方微球的粒径、机械强度、降解等性质，筛选出最佳处方；以多柔比星为模型药物研究其对药物的承载能力及体外释药特性。结果：制备的微球圆整且分散性好，粒径均匀。多柔比星海藻酸钙微球的载药量达30％以上，包封率在90％以上；在体外37℃生理氯化钠溶液中释放显示具有缓释作用。结论：该微球对多柔比星具有较高的承载能力，并有较好的缓释作用，可满足临床治疗动脉栓塞需要。     

肺靶向海藻酸钙微球体内外溶蚀行为的探讨

采用乳化法制备肺靶向海藻酸钙微球,制品平均粒径(12.2±8.9)μm,在注射用水中的溶胀率约150%,在生理盐水中24h累积溶蚀率约60%.小鼠尾静脉注射微球后肺靶向效果显著,5min时肺组织中充斥微球,6h时可见微球溶蚀.     

海藻酸钙凝胶微球中模型药物的pH值依赖性释放

目的:考察海藻酸钙凝胶微球中模型药物的pH值依赖性释放.方法:以硝苯地平为模型药,采用滴制法制备了含药微球;考察了含药微球在不同pH值介质中的释放特性.结果:含药微球在水及pH 1.0的介质中几乎不溶胀,12 h累积释放百分率为23.1%和23.4%;在pH6.8的介质中微球溶胀至完全溶蚀,且呈现缓慢释放的趋势,12 h药物的累积释放百分率为92.5%;换介质的释放中,0～2 h微球几乎不溶胀,2 h累积释放8.4%,介质pH改变后微球很快崩解,3 h累积释放82.4%.结论:海藻酸钙凝胶微球中硝苯地平的释放具有pH值依赖性,在pH 6.8的介质中缓释.     

载环孢素A海藻酸钙-壳聚糖微球的制备及体外释放特性

目的:针对角膜移植术后免疫抑制治疗需求,制备眼部局部给药的小粒径载环孢素A缓释微球,并进行体外释放考察。方法:以海藻酸钠、壳聚糖为载体材料,采用静电液滴工艺,通过向制备体系添加表面活性剂,制备小粒径载环孢素A微球,设计正交试验优化处方工艺,扫描电镜观察微球表面形态,动态透析法考察微球的体外释放特性。结果:所制微球形态良好,粒径分布窄,平均粒径为(12.4±0.8)μm,包封率为(82.8±1.8)%,载药量为(50.1±1.2)%,体外释放行为用Higuchi方程拟合效果最好。结论:采用静电液滴工艺,通过减小制备体系的表面张力,制备了球形度优良、粒径小、包封率和载药量较高的载环孢素A的壳聚糖-海藻酸盐缓释微球,所得制剂的体外释药规律服从扩散机制。     

多功能载鲣鱼肽海藻酸钙微球的制备与表征

目的 通过制剂手段掩盖鲣鱼肽原料的不良嗅味,降低其吸湿性,提高在胃中的稳定性。方法 通过微胶囊造粒仪制备载鲣鱼肽海藻酸钙微球,分别对微球的外观、鲣鱼肽含量进行表征。在25 ℃、65%RH的环境下,检测所得微球吸湿增重。分别测定在模拟胃肠液中鲣鱼肽从微球中的释放。通过顶空进样GC-MS对在热水中孵育的载鲣鱼肽微球进行检测,使用面积归一化法对有异味的挥发性组分进行定量。结果 载鲣鱼肽海藻酸钙微球微球外观圆整且大小均一,鲣鱼肽含量为18.9%。在25 ℃、65%RH的环境下,制备所得微球吸湿增重显著低于鲣鱼肽原料粉末。在模拟胃肠液中,鲣鱼肽从微球中的释放达到了肠溶制剂的标准,预示微球口服后在生理条件严苛且吸收较差的胃部对鲣鱼肽起到保护作用。通过顶空进样GC-MS法发现所制备的海藻酸钙微球可在冲泡过程中掩盖80%的异味。结论 所制备的海藻酸钙微球同时解决了鲣鱼肽原料吸湿性强、在胃中易失活和感官刺激大的缺点,为活性肽保健食品制剂的开发提供了新的思路。     

阿霉素海藻酸钙凝胶微丸的释放性

以阿霉素为阳离子模型药物，研究了不同初始浓度海藻酸钠（ＳｏｄｉｕｍＡｌｇｉｎａｔｅ，ＮａＡｌｇ）制备的空白微丸对药物的摄取作用和不同介质中药物的释放过程     

阿奇霉素壳聚糖-海藻酸钠肠溶微球的制备和评价

目的:制备阿奇霉素壳聚糖-海藻酸钠肠溶微球,并评价各因素对微球性质的影响.方法:以壳聚糖-海藻酸钠为基质材料,采用复凝聚法制备阿奇霉素壳聚糖-海藻酸钠肠溶微球.通过单因素考察研究对粒径、收率和包封率影响较大的因素,以包封率和释放度为指标进行正交设计优化最佳处方.结果:海藻酸钠浓度为3％、氯化钙浓度为2.5％、壳聚糖浓度为0.25％和投药量为20％为最佳处方.该处方制得的微球形态圆整,粒径分布合理,包封率和收率均较高.体外溶出试验表明,该条件制得的微球在酸中的释放量小于10％,可减少阿奇霉素的胃肠道不良反应;在pH6.8的缓冲液中快速释放,能迅速达到最小抑菌浓度(MIC).结论:阿奇霉素壳聚糖-海藻酸钠肠溶微球能有效避免药物在酸性环境中释放.     

Physicochemical Aspects of Percutaneous Penetration and Its Enhancement

The classic diffusion model-based interpretation of percutaneous absorption is compared to a simple kinetic analysis. The physicochemical significance and the major deductions of the two approaches are shown to be in general agreement. In particular, the effect of penetrant oil/water partition coefficient on transdermal flux is consistently predicted by the two models. Diffusional and kinetic assessments of skin penetration enhancement are then shown to reveal similar dependencies upon penetrant physical chemistry. It is demonstrated that the requirements for successful promotion of a lipophilic drug's transdermal flux are quite different from those necessary for a hydrophilic penetrant. Finally, in light of published transport data and our increased comprehension of the stratum corneum barrier function, the evidence for (and significance of) different absorption paths across the stratum corneum is considered. In addition, the impact of penetrant size on transport is addressed. It is argued that currently held beliefs concerning (i) a putative polar route through the stratum corneum and (ii) the dependence of flux on molecular weight warrant considerable further attention before their unequivocal acceptance is appropriate.     

Percutaneous Penetration of Acyclovir Through Excised Hairless Mouse and Rat Skin: Effect of Vehicle and Percutaneous Penetration Enhancer

The effects of vehicle and percutaneous penetration enhancer on the penetration of acyclovir through excised hairless mouse and rat skin were investigated. Four solvents, propylene glycol (PG), ethanol (ET), isopropanol (IPA), and isopropyl myristate (IPM), were employed as vehicles, in combination with four enhancers, l-farnesylazacycloheptan-2-one (7FU), l-geranylazacycloheptan-2-one (7GU), l-geranylazacyclopentan-2-one (5GU), and l-dodecylazacycloheptan-2-one (Azone). Acyclovir was suspended in vehicles to avoid the effect of the thermodynamic activity of acyclovir in the vehicle. The penetration of acyclovir through hairless mouse skin from IPA was enhanced by 7GU, whereas that from IPM was not affected. All combinations of vehicle and penetration enhancer were examined using rat skin. No effect of the enhancers was observed in the IPM vehicle. The estimated solubility parameters of vehicles and enhancers indicated that the polarities of IPM and the enhancers are similar, which prevents effective penetration of the enhancers from IPM. However, the penetration of acyclovir from the other vehicles was increased by the enhancers. The combination of hydrophilic vehicle and hydrophobic enhancer resulted in a large enhancing effect. The disappearance of the enhancers from the vehicle correlated with their enhancing activity, but other factors also seemed to affect the penetration enhancement of acyclovir.     

口服利福平海藻酸钠微球的制备

［摘要］目的研制口服利福平海藻酸钠微球。方法采用静电液滴法制备利福平海藻酸钠微球，测定粒径大小、包封率、载药量及其影响因素，考察微球的体外释放特点。结果微球球形圆整，分散性好，平均粒径70.2 μm，包封率83.5%，载药量17.1%，在模拟肠液中的释放呈快慢相，时间长而药物释放完全。结论以海藻酸钠、硬脂酸为材料，用静电液滴法制备利福平微球，球径小、包封率高、释药时间长，工艺简便。     

A Novel in Vitro Percutaneous Penetration Model: Evaluation of Barrier Properties with P-Aminobenzoic Acid and Two of Its Derivatives

Purpose The objective of this study was to evaluate the utility of a stratum corneum substitute (SCS) as a novel in vitro percutaneous penetration model. The SCS consists of synthetic stratum corneum (SC) lipids (cholesterol, free fatty acids, and specific ceramides) applied onto a porous substrate. The composition, organization, and orientation of lipids in the SCS bear high resemblance to that of the intercellular barrier lipids in SC. Methods The barrier integrity of the SCS was evaluated by means of passive diffusion studies, using three model compounds with different lipophilicities. The effects of lipid layer thickness, permeant lipophilicity, and altered lipid composition on the barrier properties were investigated, using isolated human SC as a control sample. Results For all three model compounds, the permeability characteristics of the SCS with a 12-μm-thick lipid layer closely resemble those of human SC. Modification of the lipid composition, generating an SCS that lacks the characteristic long periodicity phase as present in SC, was accompanied by a 2-fold increased permeability. Conclusions The SCS offers an attractive tool to predict solute permeation through human skin. Moreover, as its lipid composition can be modified, they may also serve as a suitable screening model for diseased skin.     

他克莫司软膏的制备及体外经皮渗透评价

目的 研制与原研制剂经皮渗透性能一致的他克莫司软膏。方法 用LC-MS/MS测定样品中他克莫司的含量;以剪切应力、复合黏度等流变性参数和累积释放量为指标,筛选他克莫司软膏处方;采用改良Franz扩散池,以小型猪皮肤为渗透屏障,研究他克莫司软膏的经皮渗透性能。结果 自制他克莫司软膏的剪切应力(剪切速率：30 s^-1)为145.8 Pa、复合黏度为16.11 Pa·s、释放速率为(1 400±243)ng·cm^-2·h^-1/2、经皮渗透速率为(40.28±3.11)ng·cm^-2·h^-1、皮肤内滞留量为(9.515±1.096)ng·mg^-1;原研制剂的剪切应力(剪切速率：30 s^-1)为141.8 Pa、复合黏度为15.88 Pa·s、释放速率为(1 243±133)ng·cm^-2·h^-1/2、经皮渗透速率为(37.61±9.09)ng·cm^-2·h^-1、皮肤内滞留量为(8.463±1.770)ng·mg^-1。结论 自制他克莫司软膏与原研制剂的流变性和释放速率相似,经皮渗透性无显著性差异。     

曲安奈德经皮渗透特性研究

目的评价曲安奈德经皮渗透的特性。方法采用Franz扩散池法,考察药物经完整皮肤和去角质层皮肤的体外透皮能力,并采用了胶带剥离、皮肤萃取法分别获取了皮肤角质层、去角质层皮肤样本,用HPLC法测定了样本中的药物含量,考察曲安奈德在皮肤不同层的分布情况。结果曲安奈德的24 h透过量去角质层皮肤约为完整皮肤的1.6倍;8 h透皮实验,高、中、低3个浓度角质层中药物含量基本相同,真皮层则存在浓度依赖现象。结论角质层是曲安奈德的透皮吸收重要屏障,但角质层对药物的储留有饱和现象,临床上应用时需特别关注。