伐昔洛韦生物黏附微球的制备与黏附性能研究

目的 筛选伐昔洛韦生物黏附微球的最佳处方,制备伐昔洛韦生物黏附微球并评价其黏附性能. 方法 根据单因素实验结果, 分别以收率和包封率为指标应用正交实验设计筛选最佳处方. 采用高效液相色谱法测定微球中伐昔洛韦含量, 并以滞留率为指标考察微球的黏附特性. 结果正交实验设计筛选最佳处方为伐昔洛韦投药量为30%, 分散相与连续相比为0.70, 乳化剂Span-80用量为8.0 g; 体外法与体内法测得微球胃黏膜上的滞留率分别为(90.8±3.9)%与(66.5±12.7)%. 结论该处方设计合理, 制备工艺可靠, 伐昔洛韦生物黏附微球在体内外模型中黏附性能良好.     

葛根素胃黏附微丸的制备及其体外黏附性研究

目的:制备葛根素胃黏附微丸。方法:以体外累积释放度为指标,对葛根素胃黏附微丸制备工艺中的包衣增质量、黏附材料羟丙甲基纤维素的型号、增塑剂种类及用量等进行考察,确定最优处方。以微丸胃滞留率为指标评价所制胃黏附微丸与未加入黏附材料的速释微丸的体外黏附性。结果:葛根素胃黏附型微丸的最优处方为采用1%的羟丙甲基纤维素K15M为黏附材料,包衣增质量为15%,增塑剂为相当于处方中葛根素量20%的柠檬酸三乙酯。所制3批胃黏附微丸6 h累积释放度均在90%左右,胃滞留率约为87.67%,而速释微丸的胃滞留率约为35.33%。结论:建立的葛根素胃黏附微丸制备工艺简单、操作方便,所制微丸体外黏附性较好。     

法莫替丁生物黏附型中空微球的制备与评价

目的制备法莫替丁生物黏附型中空微球,并对其进行初步评价。方法采用溶剂-扩散挥发法制备法莫替丁生物黏附型中空微球,以微球包封率、收率及漂浮率为指标通过正交试验优化处方工艺,以优化处方制备的微球进行离体黏附性试验、体外溶出实验,并进行释药机理的探讨。结果法莫替丁生物黏附型中空微球的最优处方及工艺为:乙基纤维素质量浓度为27.0 g·L-1,法莫替丁质量浓度为4.8 g·L-1,无水乙醇与无水乙醚体积比为17∶3。最优处方下制得微球外观圆整,粒径分布较均匀,在扫描电镜下横切面可见明显中空结构,平均包封率和离体黏附率分别为82.0%和98.0%,在人工胃液中12 h漂浮率可达87.0%。12 h体外释放90%以上。结论该法所制中空微球在人工胃液中具有良好的漂浮、黏附及缓释特性,体外释药符合Higuchi模型。     

冬凌草甲素纳米结晶黏附性缓释片的制备及体外评价

目的制备冬凌草甲素纳米结晶黏附片,考察其体外释放性、黏附性和结晶药物形态。方法采用高压均质法将冬凌草甲素制成纳米结晶,以羟丙甲纤维素(HPMC)和卡波姆为生物黏附材料,甘露醇为稀释剂和支架剂制备冬凌草纳米结晶生物黏附性缓释片。采用紫外分光光度法测定冬凌草甲素的含量,采用正交设计结合多元线性回归,以累计释放率为主要考察指标,考察了HPMC、卡波姆、甘露醇的用量对药物溶出的影响,确定了片剂的优化处方,并对片剂的黏附性和体外药物释放做了考察。结果最佳处方含HPMC31.0%,卡波姆21.7%,甘露醇7.44%。片剂中药物以纳米结晶形式从片剂中溶出,而且具有黏附和缓释作用。结论以最佳制备工艺条件制备纳米结晶片,制备工艺简单,重现性好。同时体外实验表明,冬凌草甲素纳米结晶生物黏附性缓释片显示了纳米结晶与生物黏附的双重优点。     

硝苯地平生物黏附微球的制备及释药机制研究

目的:制备硝苯地平生物黏附微球并考察其体外释药情况。方法:在单因素考察的基础上应用正交设计筛选硝苯地平生物黏附微球的最佳处方,因素为加热温度、聚乙烯醇(PVA)用量、司盘浓度和戊二醛用量,评价指标为累积释药率;考察优化处方所制微球的质量指标如体外黏附力和累积释药率等,研究其释药机制。结果:优化处方工艺为:加热温度60℃、PVA用量0.6 g、司盘浓度5%、戊二醛用量0.6 mL;优化处方所制微球体外黏附力较高,平均载药量约为15%,包封率约为85%,平均粒径约为20μm;微球可持续24 h释药,释药符合Higuchi方程,释药机制符合非Fick扩散机制,即以溶蚀和扩散2种模式释放。结论:硝苯地平生物黏附微球制备工艺简单,具有较好的体外黏附性能和缓释效果。     

喷雾干燥法制备斑蝥素壳聚糖生物黏附微球的处方工艺研究

摘 要 目的：优选斑蝥素壳聚糖生物黏附微球的最佳处方工艺。方法: 采用喷雾干燥法制备微球,运用单因素试验考察不同壳聚糖分子量对微球胃黏膜黏附率的影响,不同药载比、壳聚糖醋酸溶液浓度和蠕动泵速度对斑蝥素包封率的影响。采用效应面法,以斑蝥素的包封率为考察指标,进一步优化药载比、壳聚糖醋酸溶液浓度和蠕动泵流速3个因素。结果: 斑蝥素壳聚糖生物黏附微球的最佳处方工艺为：斑蝥素和壳聚糖的重量比为19.83%,壳聚糖醋酸溶液浓度为0.77%,蠕动泵流速为9.225 ml·min-1。以最佳处方工艺制得的斑蝥素壳聚糖生物黏附微球包封率为90.14%。结论: 采用喷雾干燥法制备微球,具有工艺稳定、可重复等优点,制备的斑蝥素壳聚糖生物黏附微球具备较好的包封率和生物黏附性能。     

乳化-溶媒萃取法制备阿昔洛韦生物黏附缓释微球及其工艺影响因素

采用乙基纤维素(EC)为骨架材料、卡波姆974P为生物黏附材料、丙酮为分散相溶剂、含Span-80的轻质液体石蜡为连续相,采用乳化-溶媒萃取法制备阿昔洛韦(1)生物黏附缓释微球.考察了1原药粉体的粒径对微球形态、载药量、包封率及体外释放行为的影响.结果表明,采用较小粒径(＜50 μm)原药可制得包封率较高、突释效应较小的微球.在此基础上进行了工艺放大试验,并用以进行体内外黏附性和大鼠体内药动学研究.与未添加卡波姆的1-EC微球相比,所制生物黏附微球在小鼠及大鼠的胃及小肠黏膜表面具有较好的黏附性,显著延长了药物在胃肠道内的滞留时间.大鼠药动学试验表明,本品与1混悬液相比能显著提高生物利用度.     

挤出滚圆法制备马来酸曲美布汀胃黏附微球

目的利用适合于工业化生产的方法制备具有较好生物黏附能力和适宜缓释效果的马来酸曲美布汀胃黏附微球。方法通过挤出滚圆法制备马来酸曲美布汀胃黏附微球 ;以动物体内外胃黏膜表面滞留程度 ,考察CP的含量和微球粒径对微球黏附能力的影响 ;以体外释药速率评价热处理 ,CP的含量 ,CP、SA与EC间的比例 ,TM含量 ,微球粒径对微球缓释效果的影响 ;以镇痛效果考察最终处方的药效。结果CP比例增加 ,微球的黏附性增强 ,药物缓释效果降低 ,呈现负相关 ;TM含量增加 ,微球的黏附性降低 ,缓释效果降低 ;微球粒径增大 ,微球的黏附性降低 ,缓释效果增加 ;最佳处方的作用时间延长 ,作用强度增强。结论载药量在 2 0 % (w)以下 ,粒径为 5 0 0～ 90 0 μm,CP含量为 1 3 3 0 % (w)的TM微球在胃黏膜表面具有良好的黏附特性 ,且药物缓释可达 8h。     

盐酸索他洛尔生物粘附微球的制备及体外释药特性研究

目的：制备盐酸索他洛尔生物粘附微球,考察其体外释药特性并评价其粘附性能。方法：应用正交试验筛选盐酸索他洛尔生物粘附微球的最佳处方,采用高效液相色谱法测定盐酸索他洛尔生物粘附微球的含量与释放度,选用滞留率为指标考察微球的粘附特性。结果：盐酸索他洛尔生物粘附微球的最佳处方为盐酸索他洛尔投药量占处方组成的30％．分散相与连续相比为70％,司盘80用量为9．0g;体外释药试验结果表明盐酸索他洛尔生物粘附微球30min累积释药百分率达30％,4h释药达90％;离体法与在体法测得微球胃黏膜上的滞留率分别为（87．6±2．8）％与（60．2±9．8）％。结论：盐酸索他洛尔生物粘附微球处方设计合理,制备工艺简单,与盐酸索他洛尔普通片相比,盐酸索他洛尔生物粘附微球具有一定缓释特性,且其在离体与在体模型中粘附性能良好。     

Box-Behnken效应面法优化塞来昔布微球制备工艺

目的：制备塞来昔布聚乳酸-羟基乙酸共聚物（PLGA）载药微球,优化其处方和制备工艺,考察其体外释药行为。方法：分别以油相中PLGA浓度、水相PVA浓度和油/水相体积比为考察因素,以包封率为考察指标,采用Box-Behnken效应面法优化塞来昔布微球的处方和工艺;透析袋法评估其体外释放能力。结果：塞来昔布PLGA微球的最佳处方工艺条件为：PLGA浓度75 g·L^-1,水相PVA体积分数1.5%,油/水相体积比1∶30。所制备的微球形态圆整,大小均一,实测包封率为66.1%,与预测值67.3%相比,偏差为1.8%。最优处方体外14 d累积释药56%,体外释放曲线符合Higuchi方程。结论：Box-Behnken效应面法简便可行,可用于优化塞来昔布PLGA微球的制备,微球体外释放具有缓释效果。     

盐酸索他洛尔生物黏附微球的体外释药及黏附性能研究

目的考察盐酸索他洛尔生物黏附微球的体外释药特性并评价其黏附性能。方法采用高效液相色谱法测定释放介质与微球中盐酸索他洛尔含量,并以滞留率为指标考察微球的黏附特性。结果盐酸索他洛尔生物黏附微球30min累积释药百分率达30％,4h释药达90％;离体法与在体法测得微球胃黏膜上的滞留率分别为87．60±2．8％与60．2％±9．8％。结论盐酸索他洛尔高效液相色谱测定方法简便、可靠,与盐酸索他洛尔普通片相比,盐酸索他洛尔生物黏附微球具有一定缓释特性,且其在离体与在体模型中黏附性能良好。     

Development of Biodegradable Starch Microspheres for Intranasal Delivery

Domperidone microspheres for intranasal administration were prepared by emulsification crosslinking technique. Starch a biodegradable polymer was used in preparation of microspheres using epichlorhydrine as cross-linking agent. The formulation variables were drug concentration and polymer concentration and batch of drug free microsphere was prepared for comparisons. All the formulations were evaluated for particle size, morphological characteristics, percentage drug encapsulation, equilibrium swelling degree, percentage mucoadhesion, bioadhesive strength, and in vitro diffusion study using nasal cell. Spherical microspheres were obtained in all batches with mean diameter in the range of above 22.8 to 102.63 μm. They showed good mucoadhesive property and swelling behaviour. The in vitro release was found in the range of 73.11% to 86.21%. Concentration of both polymer and drug affect in vitro release of drug.     

Preparation and evaluation of glyceryl monooleate-coated hollow-bioadhesive microspheres for gastroretentive drug delivery

The purpose of this study was to produce hollow and bioadhesive microspheres to lengthen drug retention time in the stomach. In these microspheres, ethylcellulose was used as the matrix, Eudragit EPO was employed to modulate the release rate, and glyceryl monooleate (GMO) was the bioadhesive polymer in situ. The morphological characteristics of the microspheres were defined using scanning electron microscopy. The in vitro release test showed that the release rate of drug from the microspheres was pH-dependent, and was not influenced by the GMO coating film. The prepared microspheres demonstrated strong mucoadhesive properties with good buoyancy both in vitro and in vivo. Pharmacokinetic analysis indicated that the elimination half-life time of the hollow-bioadhesive microspheres was prolonged, and that the elimination rate was decreased. In conclusion, the hollow-bioadhesive synergic drug delivery system may be advantageous in the treatment of stomach diseases.     

Stomach specific anti-helicobacter pylori therapy: preparation and evaluation of amoxicillin-loaded chitosan mucoadhesive microspheres

The purpose of this research was to formulate and systematically evaluate in vitro and in vivo performances of mucoadhesive amoxicillin microspheres for the potential use of treating gastric and duodenal ulcers, which were associated with Helicobacter pylori. Amoxicillin mucoadhesive microspheres containing chitosan as mucoadhesive polymer were prepared by simple emulsification phase separation technique using glutaraldehyde as a cross-linking agent. Results of preliminary trials indicate that volume of cross-linking agent, time for cross-linking, polymer-to-drug ratio, and speed of rotation affected characteristics of microspheres. Microspheres were discrete, spherical, free flowing and also showed high percentage drug entrapment efficiency. In vitro mucoadhesive test showed that amoxicillin mucoadhesive microspheres adhered more strongly to gastric mucous layer and could retain in gastrointestinal tract for an extended period of time. A 3(2) full factorial design was employed to study the effect of independent variables, polymer-to-drug ratio (X(1)), and stirring speed (X(2)) on dependent variables i.e. percentage mucoadhesion, t(80), drug entrapment efficiency, particle size and swelling index. The best batch exhibited a high drug entrapment efficiency of 70 % and a swelling index of 1.39; percentage mucoadhesion after 1 h was 79 %. The drug release was also sustained for more than 12 h. The polymer-to-drug ratio had a more significant effect on the dependent variables. The morphological characteristics of the mucoadhesive microspheres were studied using scanning electron microscopy. In vitro release test showed that amoxicillin released slightly faster in pH 1.0 hydrochloric acid than in pH 7.8 phosphate buffer. In vivo H. pylori clearance tests were also carried out by administering amoxicillin mucoadhesive microspheres and powder, to H. pylori infectious Wistar rats under fed conditions at single dose or multiple dose(s) in oral administration. The results showed that amoxicillin mucoadhesive microspheres had a better clearance effect than amoxicillin powder. In conclusion, the prolonged gastrointestinal residence time and enhanced amoxicillin stability resulting from the mucoadhesive microspheres of amoxicillin might make contribution complete eradication of H. pylori.     

Formulation and evaluation of stomach-specific amoxicillin-loaded carbopol-934P mucoadhesive microspheres for anti-Helicobacter pylori therapy

The purpose of this research was to formulate and systemically evaluate in vitro and in vivo performances of mucoadhesive amoxicillin microspheres for the potential use in the treatment of gastric and duodenal ulcers, which were associated with Helicobacter pylori. Amoxicillin mucoadhesive microspheres containing carbopol-934P as mucoadhesive polymer and ethyl cellulose as carrier polymer were prepared by an emulsion-solvent evaporation technique. Results of preliminary trials indicate that quantity of emulsifying agent, time for stirring, drug-to-polymers ratio and speed of rotation affected the characteristics of microspheres. Microspheres were discrete, spherical, free flowing and showed a good percentage of drug entrapment efficiency. An in vitro mucoadhesive test showed that amoxicillin mucoadhesive microspheres adhered more strongly to the gastric mucous layer and could retain in the gastrointestinal tract for an extended period of time. A 3(2) full factorial design was employed to study the effect of independent variables, drug-to-polymer-to-polymer ratio (amoxicillin-ethyl cellulose-carbopol-934P) (X(1)) and stirring speed (X(2)) on dependent variables, i.e. percentage mucoadhesion, drug entrapment efficiency, particle size and t(80). The best batch exhibited a high drug entrapment efficiency of 56%; mucoadhesion percentage after 1 h was 80% and the particle size was 109 μm. A sustained drug release was obtained for more than 12 h. The drug-to-polymer-to-polymer ratio had a more significant effect on the dependent variables. The morphological characteristics of the mucoadhesive microspheres were studied under a scanning electron microscope. In vitro release test showed that amoxicillin released slightly faster in pH 1.2 hydrochloric acid than in pH 7.8 phosphate buffer. In vivo H. pylori clearance tests were also carried out by administering amoxicillin powder and mucoadhesive microspheres to H. pylori infectious Wistar rats under fed conditions at single dose or multiple dose(s) in oral administration. The results showed that amoxicillin mucoadhesive microspheres had a better clearance effect than amoxicillin powder. In conclusion, the prolonged gastrointestinal residence time and enhanced amoxicillin stability resulting from the mucoadhesive microspheres of amoxicillin might make a contribution to H. pylori complete eradication.     

甲硝唑生物粘附微球的体外释药及其粘附性

目的研制具有良好粘附性能和缓释效果的甲硝唑生物粘附微球(Metro-EC-CP微球)。方法通过液中干燥法制备Metro-EC-CP微球。对微球理化性质、体外释药及在SD大鼠体内胃粘膜上的粘附性进行了研究。结果 微球的平均粒径为559.87 μm。体外释药符合一级动力学。微球的释药速率随着粒径的增加及载药量的减少而减慢。Metro-EC-CP微球中粘附性材料CP含量增加,其生物粘附性能增加,而其缓释效果降低。结论乙基纤维素(EC)-卡波姆934P(CP)为17∶3、载药量为25%的微球在动物体内具有良好的胃粘膜粘附性能,药物缓释达8 h。     

Nimesulide PLA microspheres as a potential sustained release system for the treatment of inflammatory diseases

Polylactic acid (PLA-L) microspheres were prepared as a biodegradable polymeric carrier for a non-steroidal anti-inflammatory drug, nimesulide. The preparation of this system was performed by the classical emulsion solvent-evaporation method. Size analysis of the microparticulate system showed that unloaded and loaded nimesulide-PLA microspheres had average diameters of about 42.9 nm and 2.1 microm, respectively. Scanning electron microscopy (SEM) of loaded and unloaded microsphere samples showed that the particles shape were perfectly spherical, the loading efficiency of nimesulide in PLA microspheres was 70%; Thus, the microparticle system evaluated in this work showed the potential to act as a sustained release system for nimesulide: in vitro dissolution profiles showed the PLA-L microparticles were able to sustain the release of the drug for a considerable period of time (28.7% within 108 h).     

The study of drug release from microspheres adhered on pig vesical mucosa

The object of our work is the preparation of a mucoadhesive drug delivery system intended for intravesical application. In the present work, microspheres with Eudragit RS matrix polymer and different mucoadhesive polymers, i.e. chitosan hydrochloride (Ch), sodium salt of carboxymethyl cellulose (CMC) and polycarbophil (PC) were prepared to evaluate their influence on the mucoadhesive properties of microspheres. Different parameters were determined and their influence on pipemidic acid release from microspheres adhered on intact and damaged pig vesical mucosa was evaluated: swelling of polymers, mucoadhesion strength of polymeric films and drug dissolution according to USP XXIV method. The dissolution rate from microspheres containing different mucoadhesive polymers decreases as follows: PC>Ch>CMC. PC swelled to the largest volume among all polymers and as a result the fastest release of the drug from PC microspheres was obtained. The release rate of pipemidic acid from microspheres adhered on intact mucosa followed the order PC>CMC>Ch. These results show that both drug dissolution and mucoadhesion strength strongly influence drug release from adhered microspheres. The slowest release from Ch microspheres could be interpreted by the largest mucoadhesion strength of Ch polymeric films. The release rate of pipemidic acid from microspheres adhered on damaged mucosa followed the order PC=Ch>CMC. The results obtained on pathologically changed mucosa model support the indication of the role of glycosaminoglycans and polymer charge in the mucoadhesion process on vesical mucosa. Analysis of release data shows that the drug dissolution profiles follow the Higuchi kinetics better than the release profiles from adhered microspheres and different kinetics might be a consequence of different release mechanisms.