盐酸环丙沙星缓释微丸的研制

目的:制备盐酸环丙沙星缓释微丸(CPSP),并对其体外释药行为进行研究.方法:粉末层积法制备了缓冲型和非缓冲型2种微丸,分别以Eudragit RL 30D,RS 30D水分散体混合物和Eudragit NE 30 D,L 30D55水分散体混合物为包衣材料制备CPSP.分别考察了包衣增重、包衣液中聚合物比例及介质pH对CPSP体外释药行为的影响.结果:选取含有柠檬酸的缓冲型丸芯,包衣增重为7%,RL与RS质量比为1:1.5时,体外释放呈非pH依赖型;包衣增重为4%,Eudragit NE 30D与L 30D55质量比为1:1时释放较理想,体外释放呈显著的pH依赖性.结论:CPSP具有较好的释药性能及良好的缓释效果.     

克拉霉素缓释包衣微丸的制备及体外释放度研究

目的制备克拉霉素缓释包衣微丸,并对其体外释放度进行考察。方法采用挤出滚圆技术制备克拉霉素含药微丸。以优化的丙烯酸树脂类Eudragit NE30D和Eudragit L30D-55混和水分散体为包衣材料,采用流化床包衣技术,制备缓释包衣微丸。考察自制缓释微丸的体外释药速率,并与市售的克拉霉素缓释胶囊进行比较。结果通过释药行为的评价,得到优化的包衣处方为5∶1的Eudragit NE30D和Eudragit L30D-55混和包衣材料,其体外释放行为在不同的pH溶出介质中与市售制剂产品没有明显差异,体外释药过程符合一级释放模型。结论采用挤出滚圆和流化床技术,以及优化的Eudragit NE30D和Eudragit L30D-55混和水分散体包衣材料,成功制备了克拉霉素缓释包衣微丸。     

离心造粒法制备托拉塞米缓释小丸胶囊及其释放度考察

目的:制备托拉塞米缓释小丸胶囊。方法:采用离心造粒粉末层积法制备托拉塞米小丸,用丙烯酸树脂水分散体包衣,并对包衣小丸的释药特征进行探讨。结果:微晶纤维素(MCC)空白母核32～40目的收率约80.2%,含药素丸20～24目收率约87.6%,使用Eudragit NE30D包衣液,包衣增重10%。托拉塞米缓释胶囊体外释药行为较好地符合Higuchi方程。结论:在优化的工艺条件下可制得表面光滑、圆整度高的托拉塞米缓释小丸。     

卡托普利控释微丸的研制

目的：制备卡托普利控释微丸，并对其释药情况进行研究。方法：在流化床内，用丙烯酸树脂RL30D和丙烯酸树脂RS30D的混合物作为包衣材料制备卡托普利控释微丸，对包衣材料配比及包衣材料用量进行选择，对微丸体外释药方程进行研究，采用加速试验法考察微丸释药稳定性。结果：包衣材料最佳配比丙烯酸树脂RL30D-丙烯酸树脂RS30D为1：5，包衣材料最佳用量为包衣增重20％，微丸的体外释药方程为Q＝0．09614t-0．008379(r＝0．9980)，释药稳定性好。结论：卡托普利控释微丸具有良好的零级释药特征。     

氟比洛芬乙基纤维素水分散体包衣小丸的制备及体外释药特性

目的：制备氟比洛芬包衣小丸，评价其体外释药特性。方法：离心造粒法制备空白丸芯及载药小丸；以乙基纤维素水分散体为包衣材料，羟阿基甲基纤维素为致孔剂，流化床制备氟比洛芬包衣小丸；释放度实验考察小丸的体外释药特性。结果：包衣小丸缓释胶囊的释放曲线与进口缓释胶囊ForbensR相似，羟丙基甲基纤维素的用量和介质pH值对释药影响显著，而热处理时间和胶囊壳对释药无显著性影响。结论：氟比洛芬包衣小丸具有较理想的体外缓释效果。     

甲硝唑缓释微丸的研制

目的制备甲硝唑缓释微丸,并对其体外释药行为进行研究。方法采用离心造粒技术制备甲硝唑丸;并在此基础上,在流化床内采用丙烯酸树脂水分散体对其进行包衣,制备甲硝唑缓释微丸。分别考察包衣材料的比例及用量对甲硝唑缓释微丸体外释药行为的影响。结果包衣材料EudragitNE30D与EudragitL30D-55质量比为1∶1、增重8%时,甲硝唑缓释微丸在模拟人体胃肠道的pH溶液中释放较理想。结论采用离心造粒技术和丙烯酸树脂流化床包衣,成功地制备了甲硝唑缓释微丸,它具有良好的缓释效果。     

盐酸氨溴索包衣小丸的制备及其释药特性

目的：研制盐酸氨溴索（Amb）包衣小丸，评价其体外释药特性及释药机制。方法：Glatt流化床底喷装置中混悬液法上药制备载药小丸，分别以不同eudragit RS100/eudragit RL100配比为包衣材料制备包衣小丸，释放度试验及扫描电镜考察小丸的体外释药特性及释药机制。结果：包衣小丸在扫描电镜下表面光滑圆整，纵切面层次分明；4种小丸配比而成的缓释胶囊释药曲线与进口缓释胶囊兰勃素差异无显著性，且不受介质pH和转篮转速等因素影响；包衣小丸的释药机制可能为浓度梯度作用下Amb按Fick's定律从完整eudragit膜聚合物链间的分子孔隙扩散。结论：Amb包衣小丸具有理想的缓释效果。     

阿昔洛韦缓释微丸的研制

目的制备阿昔洛韦缓释微丸,并对其体外释药情况进行研究。方法采用离心造粒技术制备阿昔洛韦素丸,在流化床内采用丙烯酸树脂水分散体对其包衣,制备阿昔洛韦缓释微丸。对包衣材料种类、配比及用量进行选择,对包衣微丸体外释药机理进行研究。结果包衣材料EudragitNE30D与L30D-55质量比为12∶1、增重8%时包衣微丸在pH6.8的磷酸盐缓冲液中呈现良好的缓释效果,体外释药过程基本符合Higuchi方程:Y=0.405+30.021t(r=0.9912)。结论采用离心造粒技术和丙烯酸树脂流化床包衣,成功地制备了阿昔洛韦缓释微丸,其体外释药缓慢、持续、平稳。     

盐酸二甲双胍缓释微丸的制备及体外释放度考察

目的:制备盐酸二甲双胍(metformin hydrochloride,MH)缓释微丸,并考察其体外释药行为。方法:通过离心造粒法制得MH微丸,以乙基纤维素水分散体(Surelease),丙烯酸树脂水分散体(EudragitNE30D,RS30D)作为膜控释包衣材料,通过流化床包衣制备MH缓释微丸,并考察不同包衣材料、包衣增重、固化时间、释放介质对释放度的影响。结果:离心造粒制得微丸圆整度好,有一定强度,适合包衣,Surelease包衣增重11%时所得的缓释微丸在12 h具有明显的缓释效果,不受释放介质的影响,为零级释放,且12 h释放可以达到85%以上。释放机制主要是通过无孔膜扩散作用。结论:通过离心造粒并用Surelease包衣的MH缓释微丸缓释效果明显,且为零级释放。     

盐酸青藤碱缓释微丸的研制

目的：制备盐酸青藤碱缓释微丸，并对其体外释药行为进行研究。方法：采用离心造粒技术制备盐酸青藤碱素丸，在流化床内采用丙烯酸树脂水分散体对其包衣，制备盐酸青藤碱缓释微丸。对包衣材料种类、配比及用量进行选择，对包衣微丸体外释药机理进行研究。结果：包衣材料Eudragit NE30D增重5％时，包衣微丸在水中呈现良好的缓释效果，体外释药过程基本符合Higuchi方程：Y=0．0938＋0．0846t（r=0．9965）。结论：采用离心造粒技术和丙烯酸树脂流化床包衣，成功地制备了盐酸青藤碱缓释微丸，其体外释药缓慢、平稳。     

Influence of an enteric polymer on drug release rates of theophylline from pellets coated with Eudragit RS 30D

The purpose of this research study was to investigate the influence of an enteric polymer on the drug release properties of theophylline pellets coated with Eudragit RS 30D. Theophylline pellets were coated with aqueous colloidal dispersions of Eudragit RS 30D containing various amounts of Eudragit L 100-55. The effect of storage conditions on the release of drug from coated pellets was determined as a function of the pH of the dissolution medium. The results from the dissolution study showed significant changes in the dissolution rate of theophylline from pellets coated with Eudragit RS 30D when cured at 40 degrees C for 4 days. No change in the drug release rate was observed when Eudragit L100-55 was present in the Eudragit RS 30D dispersion. Increasing the ratio of Eudragit L100-55 to Eudragit RS 30D resulted in faster drug release rates from the coated pellets. An increase in the pH of the dissolution medium was found to enhance drug release from the pellets coated with Eudragit RS 30D containing Eudragit L 100-55. Theophylline pellets when coated with Eudragit RS 30D containing the enteric polymer Eudragit L100-55 demonstrated no aging effects when stored at elevated temperatures. The overcoating of the pellets with Eudragit RD 100 did not affect the drug release profiles and prevented the particles from agglomerating during curing and storage.     

豆腐果素缓释微丸包衣工艺的研究

分别以Surelease、Eudragit RS30D／RL30D为包衣材料，制备豆腐果素缓释微丸，筛选包衣工艺的优化参数。结果表明，用Surelease、Eudragit两种包衣材料均可得到在12h内缓慢释放的微丸，后者有近1h的时滞。     

酒石酸美托洛尔缓释微丸的制备及处方因素考察

目的：选用Eudragit RS 30 D与Eudragil RL30D两种包衣材料，制备日服2次的酒石酸美托洛尔缓释徽丸，并对其处方因素进行考察。方法：采用Glatt流化床底喷溶液上药法制备载药微丸，考察缓释聚合物Eudragit RS 30D与Eudragit RL 30D的不同质量配比（2：3，7：3和9：1）、聚合物包衣增重（10％，20％和30％）以及增塑利嗣量（10％，20％和40％）和放置时间对药物释放的影响。结果：当Eudragit RS 30D与Eudragit RL 30D的质量比为9：1，聚合物包衣增重为20％，增塑剂用量为20％时，药物的释放行为符合中国药典对缓释制剂释放度的相关规定。结论：通过调整Eudragit RS 30D与Eudragit RL 30D之间的比例，或提高聚合物包衣增重等手段，能使酒石酸美托洛尔载药徽丸具备较理想的缓释效果。     

Design and study of ibuprofen disintegrating sustained-release tablets comprising coated pellets.

One challenge in tableting of sustained-release multiparticulates is maintaining the desired drug release after compaction. The aim of this study was to design sustained-release ibuprofen tablets which upon oral ingestion rapidly disintegrate into sustained-release pellets in which the integrity of the pellet core and/or coat is preserved. First free films composed of Eudragit RS 30D and RL 30D in 4:1 ratio and containing different levels of triethyl citrate (TEC) were prepared and tested to optimize the plasticizer level. Cured Eudragit based pellets with 60% ibuprofen loading which in our previous study showed proper mechanical properties for compression were coated with Eudragit RS 30D/RL 30D (4:1) containing 20% triethyl citrate at different coating levels. The mechanical properties of the coated pellets were tested. Polymer coated pellets were compacted into tablets either alone or with a blend of excipients comprising Avicel, PEG 4000, cross-linked PVP. A 3(2) full factorial design was used to optimize the filler blend composition. Effects of pellet to filler ratio, compression force and granulation of filler on tablet characteristics were investigated. Results of mechanical test showed that the coating of cured pellets had no significant effect on yield point and elastic modulus of the pellets. In the case of 5% coating level sustained release of ibuprofen over a period of 24h was achieved. The results obtained from tableting procedure showed that by selecting suitable filler blend (60% Avicel, 10% cross-linked PVP and 30% PEG 4000), compression force, and granulation of filler it was possible to prepare sustained-release tablets containing high ratio of coated pellets (even 80%) with desirable strength, disintegration time, and drug release rate. It was observed that compression force, pellet to filler ratio, composition of filler blend and granulation of fillers had no effect on drug release rate from compacted pellets but had significant influence on tablet strength, friability, and disintegration time. SEM graphs and in vitro release profiles for compacted pellets showed no apparent damage to the coated pellets as a result of the compaction process.     

A novel pH- and time-based multi-unit potential colonic drug delivery system. I. Development

A novel delivery system was developed for delivering drugs to the colon by selecting polymethacrylates with appropriate pH dissolution characteristics for the distal end of the small intestine and relying upon the relatively constant transit time of the small intestine. Pellets were prepared by powder layering of 5-aminosalicylic acid (5-ASA) on nonpareils (0.5-0.6 mm) in a conventional coating pan. Drug-layered pellets were coated with an inner layer of a combination of two pH-independent polymers Eudragit RL and RS (2:8), and an outer layer of a pH-dependent polymer, Eudragit FS. Scanning electron micrograph (SEM) pictures of the coated pellets showed the uniformity of both the coatings. The release profile of 5-ASA was studied in three phosphate buffers after a simulated gastric pre-soak for 2 h in pH 1.2 media. There was no drug release for 12 h at pH 6.5. There was a sustained release of 5-ASA for over 12 h both at pH 7.0 and 7.5 after a lag time at pH 7.0 and no lag time at pH 7.5. The release rate was faster at pH 7.5 than at pH 7.0. The delivery system demonstrated its potential for colonic delivery by resisting drug release until pH 6.5 and the combination of Eudragit RL and RS proved successful for the sustained delivery of 5-ASA at the expected pH of the colon.     

pH依赖—缓释型美沙拉秦结肠靶向小丸的制备与体外评价

以肠溶型和渗透型丙烯酸树脂为包衣材料制备ｐＨ依赖－缓释型美沙拉秦结肠靶向小丸,评价其体外释放特性。结果表明,包衣小丸在０．１ｍｏｌ／ＬＨＣｌ中２ｈ几乎不释放药物,在ｐＨ７．５缓冲液中具有较好的缓释作用。在模拟胃肠道各区段最高的和最低的ｐ变化的释放度试验中,均在对应小肠区段时开始缓慢释药。分别有４０％和７０％的药物进入结肠后释放。优于单独的肠溶或缓释制剂。     

银杏内酯缓释微丸的制备及释放度研究

目的制备可4种成分同步释放的银杏总内酯缓释微丸,并对其体外释放进行评价。方法以Eudragit RS 30D/RL 30D为包衣材料,制备银杏内酯缓释微丸,以银杏内酯A、B、C和白果内酯为指标进行体外释放度评价,高效液相色谱法进行含量测定,筛选优化包衣处方及工艺参数。结果当EudragitRS 30D和RL 30D的比例为8∶2,增塑剂和抗黏剂的用量分别为20%和50%、包衣增重为10%时,制备得到的微丸可实现4种成分同步12 h缓释释放。结论本研究微丸制备工艺快速、简便、高效,适合工业化生产。     

Effect of pectinolytic enzymes on the theophylline release from pellets coated with water insoluble polymers containing pectin HM or calcium pectinate

Theophylline pellets were coated with cellulosic (Aquacoat ECD 30, Surelease clear) or acrylic (Eudragit NE30D, RS30D) polymer aqueous dispersions, containing 10% (related to the insoluble polymer content) of pectin HM or calcium pectinate, using a Uni-Glatt fluidized-bed coating apparatus. When commercial pectinolytic enzymes were added to the dissolution media (0.05 M acetate - phosphate buffer, pH 6.0), the release of theophylline from the coated pellets was generally slower than that observed in the media without enzymes. The enzymatic slowing down of the drug release, depending on the type of the aqueous polymer dispersion used, is more important with mixed Eudragit NE/calcium pectinate coated pellets. The results obtained have been examined with regard to the validity of the approach based on the combination of pectins and the insoluble polymer aqueous dispersions intended for specific-delivery of drugs to the colon. The mechanism of the hydrophilic drug release from pellets coated with insoluble polymer aqueous dispersions containing an aqueous gel-forming polymer has been also discussed.     

不同包衣条件下银杏缓释微丸体外释放考察

目的考察不同包衣条件下银杏缓释微丸的体外释放。方法采用单因素考察及正交设计法。结果以丙烯酸树脂EudragitRL30D和EudragitRS30D为包衣材料,质量比为4∶1,包衣增重10 % (w) ,增塑剂的用量为2 0 % (w ) ,无需熟化,可满足2 4h缓释的要求。结论包衣量、衣膜中两种丙烯酸树脂的配比和包衣温度是影响药物释放的关键因素     

硝苯地平膜控型控释微丸的制备及体外评价

目的研究硝苯地平(NF)膜控型24 h控释微丸的处方与工艺,并考察其体外释放特性。方法采用液相层积、丸芯上药法制备载药速释微丸,以Eudragit RL100、RS100为包衣材料,流化床悬浮包衣法制备膜控型控释微丸,并对影响微丸释放的处方因素进行了考察。通过与市售渗透泵片拜新同的体外释放度的对比研究,探讨硝苯地平膜控型控释微丸的体外释药特征。结果调整Eudragit RL100、RS100的比例、衣层厚度、致孔剂的用量,可以改变药物的释放速率。当Eudragit RL100、RS100的比例为3∶7,包衣增重为6%时,制备的控释微丸体外释药与市售渗透泵片相似(f2=62.8),具有良好的零级释放特性。结论以丸芯上药法,Eudragit RL100、RS100为控释材料制备的NF膜控型控释微丸,具有良好的零级释放特性,结果可为硝苯地平多单元控释制剂的研究开发提供参考。