头孢氨苄胃漂浮缓释片的制备与质量评价

目的制备头孢氨苄胃漂浮缓释片,并考察其漂浮延迟时间及体外药物释放度。方法采用粉末直接压片工艺制备头孢氨苄胃漂浮缓释片,采用单因素实验方法筛选得到影响头孢氨苄胃漂浮缓释片体外漂浮延迟时间、漂浮时间和释放度的关键性辅料用量范围,最终以羟丙甲纤维素(HPMC K15M)用量、碳酸氢钠用量以及压片主压力作为考察因素,以头孢氨苄胃漂浮缓释片的漂浮延迟时间和1,4和8 h时间点的药物释放度作为评价指标,通过Box-Behnken实验设计优化得到头孢氨苄胃漂浮缓释片处方设计空间,并在设计空间任取一点连续制备3批头孢氨苄胃漂浮缓释片,评价其漂浮延迟时间及体外释放度。结果优化得到头孢氨苄胃漂浮缓释片的处方设计空间,每片HPMC K15M用量为260 mg,碳酸氢钠用量为60 mg,压片主压力为8 kN,制备的头孢氨苄胃漂浮缓释片漂浮延迟时间仅为12.1±0.5 min,在12 h内药物释放平缓,无药物突释。结论通过Box-Behnken实验设计优化得到的头孢氨苄胃漂浮缓释片处方,漂浮延迟时间较短,12 h维持漂浮状态,药物释放平稳。     

黄连总生物碱胃内漂浮缓释片处方组成的研究

目的：研究黄连总生物碱胃内漂浮缓释片的处方组成及影响因素。方法：以体外释放度为指标,筛选黄连总生物碱胃内漂浮缓释片的处方组成,采用单因素试验法,考察处方中HPMC、海藻酸钠、碳酸氢钠三个因素对其体外释放度的影响。结果：黄连总生物碱胃内漂浮缓释片较优的处方组成为HPMC13.4%,海藻酸钠26.6%,硬脂酸镁5.4%,硬脂酸42%,碳酸氢钠10.6%,HPMC与碳酸氢钠的用量显著影响黄连总生物碱胃内漂浮缓释片的体外释放度。结论：HPMC与海藻酸钠以1：2配伍使用作为片剂亲水凝胶骨架时,其体外释放度良好,且两者具有交互作用。     

胡椒碱胃内漂浮片制备工艺及体外释放度研究

目的:研制胡椒碱以羟丙甲基纤维素(HPMC)为骨架材料的胃内漂浮缓释片,并进行体外释放度研究。方法:利用亲水凝胶骨架材料HPMC及助漂剂十六醇为辅料,采用粉末直接压片和湿法制粒的方法将胡椒碱制备成胃内漂浮缓释片,并以漂浮时间及累计释放度为指标对处方进行筛选,单因素试验对处方进行优化。结果:制备的胃内漂浮缓释片在HPMC-15M为54%、十六醇为10%、碳酸氢钠为10%、硬脂酸镁1%时在人工胃液中10min内起漂,维持释放药物10~12h,累计释放度为95.6%,接近一级释放。结论:所制备胡椒碱胃内漂浮缓释片释放药物速率平稳,具有长效作用。     

阿莫西林漂浮缓释片的制备及体外释放度研究

目的　将阿莫西林制成胃漂浮缓释片 ,延长在胃中的停留时间 ,逐渐释放 ,提高生物利用度。方法　采用HPMC、十六醇等材料 ,全粉末直接压片法制备阿莫西林漂浮缓释片 ,并进行体外漂浮性与体外释放度的研究。结果　按L9(34)设计最佳制备工艺为A3 B1C2 ,阿莫西林漂浮缓释片具有很好的缓释效果。结论　制备漂浮缓释片是提高阿莫西林生物利用度的有效途径     

氢氯噻嗪胃内漂浮片的处方及体外释放研究

目的 摸索氢氯噻嗪胃内漂浮片的处方,研究其体外释药行为.方法 以HPMC为凝胶骨架、NaHCO3为起漂剂制备氢氯噻嗪胃内漂浮片,以释放度和起漂时间为指标,应用星点设计-效应面法优化处方.结果 优化得到最优处方范围,并进行处方验证,其结果偏差率在±6%以内.胃内漂浮缓释片均能在1 min内起漂,并持续漂浮8 h.体外释放...     

星点设计-效应面法优化尼可地尔胃漂浮缓释片制剂处方

目的:应用星点设计-效应面法对尼可地尔胃漂浮缓释片进行处方优化。方法:采用粉末直接压片法,以制剂辅料中HPMC、十八醇和碳酸氢钠的用量为考察因素,以1,4,8 h的累积释放度和漂浮性能为评价指标,应用星点设计-效应面法优化制剂处方,并对胃漂浮缓释片释药机理做初步研究。结果:最佳制剂处方为:HPMC 60 mg、十八醇40 mg、碳酸氢钠30 mg;经处方验证,体外累积释放度的预测值与实测值偏差<5%,起漂时间<5 min,续漂时间>8 h;经Ritger-Peppas方程拟合,n=0.5357,提示该缓释片体外释放为非Fick扩散,具扩散与骨架溶蚀的双重机制。结论:应用星点设计-效应面法优选出了最佳制剂处方,按最佳制剂处方制备的尼可地尔胃漂浮缓释片具有良好的漂浮性能和缓释特性,制备方法简便。     

尼群地平缓释片的制备及体外释放

目的:研究尼群地平(nitrendipine)缓释片的制备,以及考察其缓释片的体外释放行为。方法:制备尼群地平-聚维酮(PVP)固体分散体,将此固体分散体与羟丙甲纤维素(HPMC)制成亲水凝胶骨架缓释片,并对PVP用量、HPMC用量和释放介质等影响体外释药行为的因素进行了考察。结果:HPMC与PVP用量及其释放介质对药物释放行为影响显著,通过调节处方用量比例获得满意的释放效果,其体外释药过程符合零级药动学方程。结论:该法制备的尼群地平缓释片,其体外释药平稳、累积释放率高。     

阿昔洛韦胃漂浮缓释片的制备及体外释放

目的制备阿昔洛韦胃漂浮缓释片,并通过紫外分光光度法考察其体外释放影响因素。方法以阿昔洛韦为模型药物,分别以壳聚糖、羟丙基甲基纤维素K15M(HPMC K15M)、Eudragit S100和碳酸钙为基质制备胃漂浮缓释片,用释放度测定法考察影响药物释放的因素。结果随着HPMC K15M用量增加,药物的释放显著减慢,碳酸钙用量增加,药物释放加快。结论制备的阿昔洛韦胃漂浮缓释片漂浮性良好,且能够达到缓释的目的。     

纳豆激酶缓释片的制备及药物释放影响因素的研究*

目的：制备纳豆激酶缓释片并研究其体外释药影响因素。方法：采用直接压片法制备纳豆激酶缓释片，研究了不同骨架材料、HPMC用量、PVP用量、不同稀释剂、MCC用量对纳豆激酶缓释片体外释药速率的影响。结果：骨架材料和稀释剂的种类对药物释放有明显影响，释药速率随着HPMC和PVP用量的增加而减慢，而MCC用量的增加可加快药物的释放。结论：以HPMC与PVP作为混合骨架材料、MCC作为稀释剂，具有良好的缓释效果，HPMC,PVP和MCC的用量是影响药物释放速率的重要因素。     

盐酸格拉司琼胃漂浮型缓释片的质量控制

目的:对研制的盐酸格拉司琼胃漂浮缓释片进行质量研究。方法:通过测定盐酸格拉司琼片的体外漂浮时间、释放度及工艺稳定性等,对其质量进行研究;用紫外分光光度法测定主药盐酸格拉司琼的含量。结果:盐酸格拉司琼胃漂浮缓释片体外漂浮性能良好,体外释放曲线符合一级动力学方程和Higuchi方程。结论:该制剂有缓释和漂浮作用,工艺稳定,质量可控。     

应用Box-Behnken效应面法优化替硝唑胃漂浮片处方

目的:应用Box-Behnken效应面法优化替硝唑胃漂浮片处方。方法:采用Box-Behnken设计试验,考察羟丙基甲基纤维素(HPMC)、卡波姆及海藻酸钠三者在处方中的用量对缓释片的漂浮性能和释药性能的影响,通过二项式方程拟合因素与响应值之间的数学关系以优化处方,对体外释药数据进行方程拟合,探讨其释药机制。结果:优化处方为HPMC30%、卡波姆14%、海藻酸钠18%,优化处方的实测值与预测值之间比较接近;药物的释放模型符合Higuchi方程(r=0.9879),释药机制为骨架溶蚀与药物扩散双重作用。结论:通过Box-Behnken效应面法建立的模型可用于替硝唑胃漂浮片处方的优化。     

Preparation of highly porous gastroretentive metformin tablets using a sublimation method

The present investigation is aimed to formulate floating gastroretentive tablets containing metformin using a sublimation material. In this study, the release of the drug from a matrix tablet was highly dependent on the polymer concentrations. In all formulations, initial rapid drug release was observed, possibly due to the properties of the drug and polymer. The effect of the amount of PEO on swelling and eroding of the tablets was determined. The water-uptake and erosion behavior of the gastroretentive (GR) tablets were highly dependent on the amount of PEO. The water-uptake increased with increasing PEO concentration in the tablet matrix. The weight loss from tablets decreased with increasing amounts of PEO. Camphor was used as the sublimation material to prepare GR tablets that are low-density and easily floatable. Camphor was changed to pores in the tablet during the sublimation process. SEM revealed that the GR tablets have a highly porous morphology. Floating properties of tablets and tablet density were affected by the sublimation of camphor. Prepared floating gastroretentive tablets floated for over 24 h and had no floating lag time. However, as the amount of camphor in the tablet matrix increased, the crushing strength of the tablet decreased after sublimation. Release profiles of the drug from the GR tablets were not affected by tablet density or porosity. In pharmacokinetic studies, the mean plasma concentration of the GR tablets after oral administration was greater than the concentration of glucophase XR. Also, the mean AUC_0–∞ values for the GR tablets were significantly greater than the plasma concentrations of glucophase XR.     

盐酸地尔硫[艹卓]胃漂浮延迟缓释片的研制

采用干法包衣压片法制备盐酸地尔硫[艹卓]胃漂浮延迟缓释片。考察了溶出介质pH、助漂剂种类、碳酸氢钠及羟丙甲纤维素用量对制剂漂浮性能及释药行为的影响。对释药曲线的拟合结果显示，该制剂4～12h以零级动力学释药，释药机制为药物扩散和骨架溶蚀共同作用。     

A Floating Controlled-Release Drug Delivery System: In Vitro-in Vivo Evaluation

A novel floating controlled-release drug delivery system was formulated in an effort increase the gastric retention time of the dosage form and to control drug release. The buoyancy was attributed to air and oil entrapped in the agar gel network. A floating controlled-release 300-mg theophylline tablet having a density of 0.67 was prepared and compared in vitro and in vivo to Theo-dur. The in vitro release rate of the floating tablet was slower. In vivo scintigraphic studies for a floating and a heavy nonfloating tablet, under fasting and nonfasting conditions, showed that the presence of food significantly increased the gastric retention time for both tablets, and tablet density did not appear to make a difference in the gastric retention time. However, the positions of the floating and nonfloating tablets in the stomach were very different. Bioavailability studies in human volunteers under both fasting and nonfasting conditions showed results comparable to those with Theo-dur. The floating controlled-release theophylline tablet maintained constant theophylline levels of about 2 mg/mL for 24 hr, which may be attributable to the release from the agar gel matrix and the buoyancy of the tablet in the stomach.     

Effect of formulation parameters on the drug release and floating properties of gastric floating two-layer tablets with acetylsalicylic acid

Floating dosage forms of acetylsalicylic acid, used for its antithrombotic effect, were developed to prolong gastric residence time and increase bioavailability. In the two-layer tablet formulation, hydroxypropyl methylcellulose (HPMC) of high viscosity and an effervescent mixture of citric acid and sodium bicarbonate formed the floating layer. The release layer contained the drug, direct tableting agent and different types of matrix-forming polymers such as HPMC of low viscosity, sodium carboxymethylcellulose and chitosan. Tablets were prepared using a direct compression technique. The effect of formulation variables on physicochemical and floating properties and the drug release from tablets were investigated. Floating ability was dependent on the amount of effervescent agent and gel-forming polymer of the floating layer. Drug release was prolonged to 8 hours by changing the type and viscosity of the matrix-forming polymer in the drug-loading layer and all formulations showed a diffusion release mechanisms.     

左卡尼汀胃漂浮缓释片的制备及体外评价

目的:应用Box-behnken效应面法优化左卡尼汀胃漂浮缓释片处方,并评价其体外漂浮和释放特性.方法:以粉末直接压片法制备片剂.采用单因素法筛选出主要影响因素,即硬度、HPMC用量及碳酸氢钠用量,以漂浮性能和不同时间点释药性能为评价指标,通过Boxbehnken设计实验优化处方,对体外释药数据进行方程拟合,并结合扫描电子显微镜对溶出前后片剂表面形态的观察,探讨其释药机理.结果:优选处方为每片含HPMCK100M 29.7％,碳酸氢钠5.0％,十八烷醇15.0％,硬度为4 kg· mm-2.体外释药符合Makoid-Banakar模型,药物的释药机制为骨架溶蚀与药物扩散双重作用.结论:Box-behnken效应面法可用于左卡尼汀胃漂浮缓释片处方优化,且制备工艺简单,优化处方具漂浮缓释作用.     

Magnetic Resonance Imaging for the in Vivo Evaluation of Gastric-Retentive Tablets

PURPOSE: To develop a magnetic resonance imaging (MRI) technique for assessing in vivo properties of orally ingested gastric-retentive tablets under physiologic conditions. METHODS: Tablets with different floating characteristics (tablet A-C) were marked with superparamagnetic Fe3O4 particles to analyze intragastric tablet position and residence time in human volunteers. Optimal Fe3O4 concentration was determined in vitro. Intragastric release characteristic of one slow-release tablet (tablet D) was analyzed by embedding gadolinium chelates (Gd-DOTA) as a drug model into the tablet. All volunteers underwent MRI in the sitting position. Tablet performance was analyzed in terms of relative position of tablet to intragastric meal level (with 100% at meal surface), intragastric residence time (min) and Gd-DOTA distribution volume (% of meal volume). RESULTS: Intragastric tablet floating performance and residence time of tablets (tablet A-D) as well as the intragastric Gd-DOTA distribution of tablet D could be monitored using MRI. Tablet floating performance was different between the tablets (A, 93%(95 - 9%); B, 80%(80 - 68%): C, 38%(63 - 32%); p < 0.05). The intragastric distribution volume of Gd-DOTA was 19.9% proximally and 35.5% distally. CONCLUSIONS: The use of MRI allows the assessment of galenic properties of orally ingested tablets in humans in seated position.     

芍药苷胃漂浮片的制备

目的 制备芍药苷胃漂浮片,优选芍药苷胃漂浮片的制备工艺。方法 采用湿法制粒压片制备芍药苷胃漂浮片,以漂浮性能和体外累积释放率为考查指标,采用单因素筛选及正交设计法,优化芍药苷胃漂浮片处方。结果 以HPMC K4M(20%)为骨架材料、NaHCO₃(15%)为起泡剂、PVPP(7%)为释放促进剂、乳糖200为填充剂制得的胃漂浮片能立即起漂,持续漂浮12 h以上,累积释放率达90%以上。结论 优选的芍药苷胃漂浮片达到了持续漂浮及缓慢释放的要求,可操作性强。     

Design and evaluation of floating multi-layer coated tablets based on gas formation

Floating multi-layer coated tablets were designed based on gas formation. The system consists of a drug-containing core tablet coated with a protective layer (hydroxypropyl methylcellulose), a gas forming layer (sodium bicarbonate) and a gas-entrapped membrane, respectively. The mechanical properties of acrylic polymers (Eudragit^® RL 30D, RS 30D, NE 30D) and ethylcellulose were characterized by the puncture test in order to screen a suitable film for the system. Eudragit^® RL 30D was chosen as a gas-entrapped membrane due to its high flexibility and high water permeability. The obtained tablets enabled to float due to the CO₂-gas formation and the gas entrapment by polymeric membrane. The effect of formulation variables on floating properties and drug release was investigated. The floating tablets using direct-compressed cores had shorter time to float and faster drug release than those using wet-granulated cores. The increased amount of a gas forming agent did not affect time to float but increased the drug release from the floating tablets while increasing coating level of gas-entrapped membrane increased time to float and slightly retarded drug release. Good floating properties and sustained drug release were achieved. These floating tablets seem to be a promising gastroretentive drug delivery system.