多层片给药系统在定位和控制释药中的应用

多层片给药系统由含药片层及屏障层组成，通过屏障层控制药物的释放。综述近年来该给药系统在缓控释方面的研究进展，介绍其在定位释药（颊部黏膜给药、胃内定位释药和结肠定位给药）和控制释药形式（双相型释药、零级释药、双峰型释药和延时型释药）方面的应用。     

多层片释药系统研究现状及应用

随着控制释药技术的不断提高,及至90年代,多层片释药系统(multiple layer tablet as drug delivery system)越来越受到重视。该系统是在骨架片的基础上发展的一种多相释药系统,它由含有药片心及一层或多层屏障层(barri-ers)组成,屏障层作为释药调节层,通过减少药物的释放表面积及限制溶剂的渗透速度,延缓溶出介质对片心的作用,达到控制释放的目的。片心有骨架缓释型及速释型,外层阻滞层对心片进行一层或上下两层覆盖、周边覆盖或阻滞层压制包裹片心形成包心片(press coated tablet)。这种技术可针对药物不同的溶解特性及生物学特征,对药物的释放作更为精细的调节以满足各种需要,包括不同性质的复方药物在同一系统中的释放调节。阻滞层可根据药物性质特性选用溶解性、膨胀性的高分子聚合物或生物可降解物质。     

盐酸维拉帕米双脉冲多相释药杯形片的研制

本文制备了盐酸维拉帕米(verapamil hydrochloride， VH)的三层片芯及四层片芯杯形片， 分别达到脉冲控释双相释药及双脉冲多相释药。用混合粉末直接压片法制备多层片芯， 干压包衣技术制备盐酸维拉帕米杯形片， 以释药时滞(T_lag)评价杯形片顶层重量、 羟丙基甲基纤维素HPMC用量及压片压力对药物的释放效果。结果表明， 顶层重量增加及HPMC用量增大时， T_lag延长； 压片压力在6～10 kg·cm^-2时， 压力增大， 时滞延长。杯形片中药物主要通过顶层单面释药， 阻滞层(顶层及多层片芯中的缓释层)的溶蚀速率是决定释药时滞的关键因素。     

黄芩苷单层渗透泵片的制备工艺及体外释药行为研究

目的:制备黄芩苷单层渗透泵片并考察其体外释药行为。方法:以体外累积释放度为评价指标,在将黄芩苷制备成固体分散体以提高其溶解度的基础上,通过单因素及正交试验优化以黄芩苷固体分散体为中间体制备单层渗透泵片的处方制备工艺条件(促渗剂、致孔剂用量及包衣膜增质量);另考察优化工艺所制样品在3种不同释放介质(水、0.1 mol/L盐酸溶液、人工胃液)中的释放速率及释放机制。结果:最优处方制备工艺为促渗剂氯化钠的用量为30 mg、致孔剂聚乙二醇400的用量为辅料醋酸纤维素质量的20%、包衣膜增质量为2%;优化工艺所制3批黄芩苷单层渗透泵片在12 h时的累积释放度的RSD为1.06%(n=3)。其在3种介质中12 h内的累积释放度相似,均达80%以上;释药方程符合零级释药模型(r=0.998 5)。结论:经优化后的工艺制备的黄芩苷单层渗透泵片可在12 h内恒速释药。     

盐酸曲马多多层控释骨架片的体外释药规律

以羟丙基甲基纤维素为主要骨架材料 ,将高水溶性药物盐酸曲马多制成多层控释骨架片 ,研究了影响多层骨架片体外释药速率的因素。结果表明 ,通过改变盐酸曲马多多层骨架片各层组成 ,可以灵活地改变其释药速率。多层骨架片系统可以避免初始的突释现象 ,而且其体外释药规律可以接近零级。因此 ,多层骨架片系统是制备高水溶性药物控释制剂的有效方法     

酒石酸美托洛尔双脉冲片的研制

目的:制备酒石酸美托洛尔双脉冲片。方法:采用混合粉末直接压片法制备3层片芯(2层速释层和1层阻滞层),采用干压包衣技术制备杯形片,以时滞时间和累积释药率为指标,评价杯形片的顶层阻滞层辅料、用量以及压片硬度对释放行为的影响,确定片芯速释层和阻滞层处方及用量。结果:顶层阻滞层的辅料、用量以及压片硬度对释药时滞和累积释药率都有影响。确定了片芯速释层和阻滞层的处方和硬度;顶层阻滞层的用量为0.12g,可达到4h的第1个脉冲效果;片芯阻滞层的用量为70mg,可达到8h的第2个脉冲效果。结论:研制的酒石酸美托洛尔双脉冲片体外释放达到双脉冲要求。     

枸橼酸坦度螺酮渗透泵型控释片的制备及体外释药因素的考察

目的 制备枸橼酸坦度螺酮(TDS)渗透泵型控释片,考察影响其释药行为的因素,并探讨释药机理.方法 采用机械双面打孔的方法制备TDS渗透泵片,以单因素考察影响其体外释药的因素.结果 0～12 h内,TDS渗透泵控释片的体外释药以渗透压机制为主,释药速率受溶解度调节剂、促渗剂、阻滞剂的影响显著.结论 TDS渗透泵型控释片的制备工艺稳定,释放规律符合控释制剂的要求.     

尼莫地平渗透泵型控释片的研制及释药影响因素考察

目的制备中剂量难溶性药物尼莫地平单室渗透泵型控释片 ,并考察其释药机理及影响释药因素 ,探讨药物释药规律。方法单因素考察影响释药的因素。结果制备了中剂量难溶性药物尼莫地平单室渗透泵型控释片 ;氯化钠、阿拉伯树脂胶、衣膜厚度及增塑剂的用量是影响释药的主要因素。结论尼莫地平单室渗透泵型控释片工艺稳定 ,能够达到 12h明显的恒速释药     

阿魏酸哌嗪脉冲释药片的制备及其体外释药影响因素考察

目的以阿魏酸哌嗪为模型药物,考察制备脉冲给药系统的可行性。方法制备含有阿魏酸哌嗪的片芯,在外层进行乙基纤维素材料的包衣,制备脉冲释药片。通过体外释放度实验,考察片芯及包衣层处方对药物释放时滞的影响。结果片芯中崩解剂种类及用量、包衣层厚度、包衣层中致孔剂用量均对阿魏酸哌嗪脉冲释药片的释药行为有所影响。结论阿魏酸哌嗪脉冲释药片体外释放度试验中呈现良好的脉冲释药行为,并可通过调整崩解剂用量、包衣层厚度、包衣层中致孔剂用量等因素调整其释药时滞。     

黄原胶亲水性骨架片体外释药的影响因素

以茶碱为模型药物,制备了黄原胶亲水性骨架片,研究了体外释药的影响因素．结果表明,茶碱黄原胶亲水性骨架片的释药速率与骨架片中黄原胶的用量和溶出条件（ 转速、介质离子强度、ｐＨ 值） 有关,但与制备工艺条件无关．溶出介质中离子对其释药机制有影响．黄原胶能有效控制骨架片中药物释放,是一种优良的亲水性骨架材料．     

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.     

Preparation,<Emphasis Type="Italic">In vitro</Emphasis>, preclinical and clinical evaluations of once daily sustained release tablets of aceclofenac

The objective of the present study was to develop "once daily" sustained release tablets of aceclofenac by direct compression using hydroxypropyl methylcellulose-K4M (HPMC). The solubility studies of aceclofenac were conducted to select suitable dissolution media. The drug-excipient mixtures were subjected to preformulation studies. The tablets were subjected to physicochemical, in vitro drug release and stability studies. Preclinical (anti-inflammatory, analgesic, pharmacokinetic and toxicity studies) and clinical pharmacokinetic studies were conducted for optimized tablets. Based on the preformulation results, microcrystalline cellulose (MCC), dicalcium phosphate and spray dried lactose (SDL) were selected as directly compressible vehicles. Because of the incompatibility with aceclofenac, SDL was excluded from the study. The physicochemical properties of tablets were found within the limits. By comparing the dissolution profiles with the marketed product, the tablet containing HPMC (45%) and MCC (30%) along with talc and magnesium stearate (1% w/w, each) (Tablet B7) was considered as a better formulation. This tablet exhibited almost similar drug release profile in different dissolution media as that of marketed tablet. Tablet B7 was stable in accelerated conditions for 6 months. The composition of this tablet showed almost similar preclinical pharmacological activities compared to marketed tablet composition and did not exhibit any toxicity in rats and mice with respect to tested haematological and biochemical parameters along with body weight, food and water intake. The pharmacokinetic study in healthy human volunteers indicated that B7 tablet produced an extended drug release of drug upto 24 h as that of marketed product with almost identical pharmacokinetic parameters.     

氟康唑阴道缓释片的制备及体外释放的研究

目的：制备氟康唑阴道缓释片,选择最优缓释片处方,为下一步体内药动学实验和其它各项研究奠定基础。方法：以氟康唑为主药,采用三因素三水平,正交试验设计方法考察MCC,HPMC,Carbopol对氟康唑缓释片释放的影响。应用紫外分光光度法测定药物片剂的释放度和片剂中氟康唑的含量。结果：确定处方FCZ50mg Carbopol 100mg MCC 150mg。HPMC 90mg淀粉210mg为最佳处方,片重0.6g。HPMC为该片剂缓释作用的主要影响因素,卡波姆影响作用次之。结论：该制剂有望成为治疗阴道真菌感染的有效制剂。     

Controlled release reservoir mini tablets approach for controlling the drug release of Galantamine Hydrobromide

The objective of this study is to explore and investigate the reservoir mini tablets approach to control the release of Galantamine Hydrobromide in comparison to desired release profile to the Innovator formulation Razadyne^® ER capsules as disclosed in US Patent 7,160,559 which is granted to Janseen Pharmaceutica NV. The core mini tablets were prepared using the direct compression and wet granulation methods. These core mini tablets were further coated with Galantamine Hydrobromide in two different portions; 70% as controlled release and 30% as immediate release and then filled in empty hard gelatin capsule shells. The dissolution profiles of each formulation were compared to those of Razadyne^® ER capsules and the mean dissolution time (MDT), dissolution efficiency (DE%) and dissolution similarity (f2 factor) were calculated. It was observed that core formulation plays an important role in controlling the drug release as well as maintaining pH independent drug release profile. The release mechanism of GAH from reservoir mini tablet formulation follows Higuchi and first order. These results imply that controlled release reservoir mini tablets which further filled into empty hard gelatin capsule shells can be a suitable method to formulate controlled release Galantamine hydrobromide.     

布地奈德结肠定位片的体外释放度实验方法及其释药机制研究

建立3步释放度实验法考察布地奈德结肠定位片的体外释药行为，并通过模型拟合阐明其释药机制。分别模拟胃、小肠和结肠部位的pH值、肠道菌群、特异性生物酶、蠕动和转运时间等生理参数，设计定位片体外释放度试验，24 h内定时取样，HPLC法测定布地奈德的累积释放度，采用多种数学模型对定位片的释药曲线进行拟合度分析。结果表明，布地奈德结肠定位片在2 h内无药物释放，6 h累积释放度约为5%，24 h累积释放度达77.5%，其体外释药行为符合First-order模型。本实验建立的3步释放度实验可作为评价布地奈德结肠定位片结肠靶向性的方法，定位片的释药行为遵从以渗透压作为主要释药动力的微孔型渗透泵的释药机制。     

Oral Disintegration Tablets of Stavudine for HIV Management: A New Technological Approach

Stavudine oral disintegration tablets were formulated to minimize the bitter taste and to reduce the first-pass hepatic metabolism. The various precompression parameters like the angle of repose, bulk density, compressibility index and Hausner''s ratio were determined for the powder blend. In this study, 14 formulations of stavudine oral disintegration tablet were prepared by direct compression method. The tablets were evaluated for weight variation, percentage friability, disintegration time, hardness, wetting time and water absorption ratio. The in vitro dissolution study results of the batch S1 (stavudine+crospovidone+sodium starch glycollate) are encouraging as highest dissolution rate (99.2% in 100 min) and lowest time of disintegration (56 s) was achieved. The in vivo drug release studies were carried out in rabbits and the relative bioavailability of formulation S1 was found to be 2.83 times greater than that of conventional tablets.     

Microporous bilayer osmotic tablet for colon-specific delivery

Microporous bilayer osmotic tablet bearing dicyclomine hydrochloride and diclofenac potassium was developed using a new oral drug delivery system for colon targeting. The tablets were coated with microporous semipermeable membrane and enteric polymer using conventional pan-coating process. The developed microporous bilayer osmotic pump tablet (OPT) did not require laser drilling to form the drug delivery orifice. The colon-specific biodegradation of pectin could form in situ delivery pores for drug release. The effect of formulation variables like inclusion of osmogen, amount of HPMC and NaCMC in core, amount of pore former in semipermeable membrane was studied. Scanning electron microscopic photographs showed formation of in situ delivery pores after predetermined time of coming in contact with dissolution medium. The number of pores was dependent on the amount of the pore former in the semipermeable membrane. In vitro dissolution results indicated that system showed acid-resistant, timed release and was able to deliver drug at an approximate zero order up to 24 h. The developed tablets could be effectively used for colon-specific drug delivery to treat IBS.     

马来酸氨氯地平分散片处方及制备工艺研究分析

目的探讨马来酸氨氯地平分散片的处方以及制备工艺。方法通过实验对马来酸氨氯地平分散片的处方以及制备工艺进行研究。结果使用交联聚维酮和低取代羟并纤维素为崩解剂,预胶化淀粉和微晶纤维素作为填充剂,使用聚维酮-K30作为粘合剂以及二氧化硅和硬脂酸镁为润滑剂制成的马来酸氨氯地平分散片,可以在3min内崩解,并且能够通过2号筛,硬度适中,成型性好,外观光洁,可以迅速的分散,符合《中国药典》对分散片的要求。结论马来酸氨氯地平分散片符合分散片的制剂要求,溶出度比较高,崩解迅速,制备工艺简单,符合大规模生产要求。     

多西环素口腔贴片的体内外特性

目的研制一种局部使用的用于治疗牙周炎的缓释多西环素口腔贴片,并比较其黏附性及体内外释放趋势。方法采用卡伯姆、羟丙基甲基纤维素和乳糖作为辅料与多西环素混合压制成片。在体外测定片剂的粘力和释放度,在体内测定健康志愿者口腔内黏附时间和不同时间的释药量。结果平均粘力167 g;口腔内黏附时间270 min。片剂在不同释放介质中释放速度不同,在水中的释放趋势与口腔内释放较一致,4 h释放约60%。结论本品黏附性强、缓释性好,体内体外释放具有相关性,是一种治疗牙周炎的新剂型。     

星点设计-效应面法优化复方氯雷伪麻缓释片的缓释片芯处方

目的:优化复方氯雷伪麻缓释片的缓释片芯处方。方法:以氯雷他定加入包衣层并包衣硫酸伪麻黄碱片芯制备复方氯雷伪麻缓释片。采用星点设计-效应面法优化硫酸伪麻黄碱片芯处方,以单硬脂酸甘油酯(GM)和羟丙甲纤维素(HPMC)K15M用量为考察因素,以硫酸伪麻黄碱1、6、12 h的累积释放度为指标,通过重叠等高线图确定优化处方,并进行处方验证。结果:氯雷他定与欧巴代包衣粉按1∶3比例混合包衣成为速释层;硫酸伪麻黄碱片芯作为缓释层,其处方为每100片(600 mg/片)含硫酸伪麻黄碱12 g、GM 16.72 g、HPMC K15M 20.95 g、微晶纤维素9.73 g、硬脂酸镁0.6 g。优化处方所制制剂中氯雷他定15 min的累积溶出度为87.2%,硫酸伪麻黄碱1、6、12 h的累积释放度分别为34.20%、74.32%、94.60%。结论:缓释片芯处方合理、可行,所制备的复方氯雷伪麻缓释片具有缓释作用。