神衰果素亲水凝胶缓释骨架片的制备及释药机理的研究

目的制备神衰果素亲水凝胶缓释骨架片.方法以羟丙基甲基纤维素(HPMC)作为缓释材料,采用粉末直接压片工艺制备神衰果素亲水凝胶缓释骨架片,考察HPMC的用量、规格、不同的释药条件对释药速率的影响,并对释药机制作了初探.结果神衰果素亲水凝胶缓释骨架片的体外释药为非Fick扩散,HPMC的用量对药物的释放有较大影响,而HPMC的规格,释放介质的pH值对药物释放影响不大.结论以HPMC作为缓释材料,采用粉末直接压片法制备神衰果素亲水凝胶缓释骨架片,工艺简单,体外缓释效果好.     

乳洁安缓释片的制备及体外释药

目的:研制乳洁安亲水凝胶缓释骨架片,进行体外释放度考察并解析其释药机制。方法:以羟丙基甲基纤维素(HPMC)为缓释骨架材料,通过正交设计优化处方,并考察释放介质黏度、pH值、溶出方法、转速及制片工艺等因素对缓释片体外释放度的影响。结果:正交设计获最优处方为A3B1C1,即HPMC作为亲水凝胶骨架材料,用量为40%,EC用量为10%,乳糖和MCC用量均为5%。药物体外释放行为符合Higuich方程。结论:该方法制得的缓释片具有良好的缓释效果,且制备工艺简单易行。     

聚氧乙烯骨架缓释片的处方及体外释药机制研究

目的以聚氧乙烯（PEO）为亲水凝胶骨架制备缓释片剂,并考察其体外释药机制。方法基于两种规格PEO的用量比与释药速率之间的关系,优化缓释片处方。通过考察片剂的体外释放度和溶蚀比探讨其释药机制,并对不同溶解度药物的体外释放行为进行比较。结果缓释片体外释药速率与PEO用量比呈线性关系,所得优化处方在12h内以接近恒速释药,其体外释药与溶蚀过程基本同步,且在所考察用量范围内不同溶解度药物的体外释放度相近。结论PEO制成的亲水凝胶骨架片缓释性能良好,其体外释药是药物扩散和骨架溶蚀协同作用的结果。     

聚氧乙烯骨架缓释片的处方及体外释药机制研究

目的 以聚氧乙烯(PEO)为亲水凝胶骨架制备缓释片剂,并考察其体外释药机制。方法 基于两种规格PEO的用量比与释药速率之间的关系,优化缓释片处方。通过考察片剂的体外释放度和溶蚀比探讨其释药机制,并对不同溶解度药物的体外释放行为进行比较。结果 缓释片体外释药速率与PEO用量比呈线性关系,所得优化处方在12 h内以接近恒速释药,其体外释药与溶蚀过程基本同步,且在所考察用量范围内不同溶解度药物的体外释放度相近。结论 PEO制成的亲水凝胶骨架片缓释性能良好,其体外释药是药物扩散和骨架溶蚀协同作用的结果。     

4-氨基吡啶凝胶骨架缓释片的制备及体外释放

目的:制备4-氨基吡啶(4-aminopyridine,4-AP)亲水凝胶骨架缓释片。方法:以羟丙甲纤维素的规格、处方用量及乳糖处方用量为因素设计正交试验,以体外释放度为考察指标,优化4-AP凝胶骨架片的处方,并进行批内和批间体外释放度验证试验。采用Origin软件对筛选出的最优处方释放度进行Weibull曲线拟合。考察体外释放条件对药物释放的影响。结果:优化处方为HPMC规格为K100LV,处方用量为54%,乳糖的处方用量为16%。所制得4-AP凝胶骨架片可持续释药12 h,批内释放均一性及批间重复性均良好。Weibull模型拟合方程得出药物释放符合一级速率过程。体外释放条件考察结果表明,转速对药物的释放有影响,而释放介质的种类和测定装置则无显著性影响。结论:所选4-AP凝胶骨架缓释片制备工艺可行,重复性好,有明显的缓释特性。     

藤甲酰苷缓释片的制备及体外释药因素考察

目的制备藤甲酰苷缓释片并研究其体外药物释放行为。方法通过亲水凝胶骨架型缓释技术,以羟丙基甲基纤维素(HPMC)为缓释材料、乙基纤维素(EC)为凝胶骨架材料制备藤甲酰苷缓释片;考查了释放介质的pH值、骨架材料与其用量、致孔剂的类型与用量、压片压力等工艺因素和条件对藤甲酰苷缓释片体外药物释放行为的影响。结果药物的释药速率受骨架材料的规格和用量、致孔剂种类的影响;释放介质pH值、转速和压片压力对释药速率有一定影响。结论研制的藤甲酰苷缓释片处方合理,有较好的可控性和重现性。     

米诺环素亲水凝胶型缓释骨架片的制备及体外释放度考察

目的:制备米诺环素亲水凝胶型缓释骨架片并考察其体外释放度。方法:采用粉末直接压片工艺制备缓释片;采用紫外分光光度法测定其释放度,同时考察羟丙基甲基纤维素(HPMC)的不同规格、用量以及不同释药条件对药物释放速率的影响。结果:所制制剂为黄色片剂,检查项符合2005年版《中国药典》中的相关规定。试验确定了以HPMCK100为缓释骨架材料,处方用量为32%;不同释放介质与释放装置对药物的释放均有显著影响。释放规律符合Higuchi方程。结论:该制剂处方工艺简单,体外释放度测定方法准确易行,制剂具有明显的缓释效果。     

氢溴酸高乌甲素亲水凝胶骨架片的制备及体外释放

目的为了减少给药次数,方便患者,并提高镇痛效果,制备氢溴酸高乌甲素亲水凝胶骨架片,优化制剂处方,并探讨释放机制。方法以羟丙甲纤维素(HPMC)为骨架材料,乳糖、微晶纤维素(MCC)、淀粉为填充剂,硬脂酸镁为润滑剂制备氢溴酸高乌甲素骨架片,考察各因素对药物释放度的影响,筛选优化处方,并拟合讨论其释放机制。结果 HPMC的用量及分子量,微晶纤维素和硬脂酸镁的用量对药物释放有显著影响。所制缓释片无突释现象,缓释周期12 h,根据拟合方程,药物释放符合一级释放模型,其释放既有扩散,又有骨架溶蚀。结论本方法制备的氢溴酸高乌甲素缓释片工艺简单,生产成本低,且具有良好的释放性能。     

亲水凝胶在药物制剂中的应用

羟丙基甲基纤维素及卡泊波树脂遇水后均可形成亲水凝胶,在缓释制剂中通过亲水凝胶层控制药物的释放。本文影响亲水凝胶控制药物释放的因素如辅料本身的性质,药物的性质以及介质等进行了综术,并着重介绍了羟丙基甲基纤维素在骨架制剂和包衣中的作用,以及卡泊波树脂在固体缓释制剂和口服蛋白给药系统中的应用及最新进展。     

一日1次溴新斯的明缓释片的制备及体内外释放行为研究

目的以溴新斯的明为模型药物制备日服1次缇释片,并对缓释片释放特征进行初步考察。方法采用亲水凝胶骨架与薄膜包衣控释技术制备溴新斯的明缓释片,以药物释放行为为评价指标,对处方及工艺进行单因素考察结果溴新斯的明缇释片体外药物释放可维持24 h,药物释放曲线符合一级动力学方程In(100-Q)=-0.147 4 t+4.775 4,体内药动学研究表明缓释片t_(1/2)(5.1±1.8)h,较普通片t_(1/2)(3.5±1.1)h延长,具有较为明显的缓释效果。结论亲水凝胶骨架与薄膜包衣控释技术联合应用可以成功制备易溶性药物溴新斯的明的缓释制剂。     

尼莫地平由溶胀性亲水性骨架中释放的动力学

本研究选用尼莫地平PVP－K30固体分散体为原料,以羟丙基甲基纤维素（HPMC）为缓释材料,进行了尼莫地平缓释片剂处方的设计,考查其体外释药动力学,并对几种辅及及不同的制备方法对片剂释药情况的影响进行了研究。体外溶出度实验结果表明,在本实验范围内,尼莫地平由HPMC亲水性凝胶骨架片中的溶出过程更符合零级动力学。微晶纤维素的加入可使片剂释药速度加快,低粘度的羟乙基纤维素可使药物的溶出速率常数增加。将HPMC制成40目颗粒后,再行压片,可使药物溶出度减慢。本研究筛选出的缓释片剂,可在12小时内平稳释药。     

盐酸普拉克索亲水凝胶骨架缓释片的剂量倾泻研究

摘要：目的 研究体外溶出释放条件对盐酸普拉克索亲水凝胶骨架缓释片释放的影响,并对其发生剂量倾泻的风险进行评估。方法 采用HPLC法,测定其在规定时间内不同水醇浓度介质以及不同转速下的累积释放度,并通过相似因子评价其与市售制剂Sifrol?的相似度。结果 在 pH 6.8 PBS介质中75 r/min、100 r/min和200r/min条件下以及在含5%、20%、40%乙醇的0.1 moL?L-1盐酸介质中100 r/min条件下,市售制剂与自制制剂在规定时间内的累积释放度相似。结论 不同水醇浓度介质以及不同转速对盐酸普拉克索亲水凝胶骨架缓释片体外的释放度影响不大,该处方发生剂量倾泻的风险可控。     

Synthesis,characterization and evaluation of deacetylated xanthan derivatives as new excipients in the formulation of chitosan-based polyelectrolytes for the sustained release of tramadol

This paper addressed the application of deacetylated xanthan (XGDS) and chitosan (CTS) as a mixture blend forming hydrophilic matrices for Tramadol (TD) sustained release tablets. XGDSs derivatives were obtained by alkaline treatment of xanthan gum (XG) with various degrees of deacetylation (DD). The obtained products were characterized in terms of structural, thermal and physicochemical properties. Different tablet formulations containing CTS/XGDSs were prepared by direct compression method and compared to CTS/XG tablets. Flow properties of powder mixtures and pharmaceutical characteristics were evaluated. The dissolution test of TD was realized under simulated gastric and intestinal conditions to achieve drug release more than 24 h. All developed tablets were found conforming to standard evaluation tests. It was shown that CTS/XGDSs matrices ensure a slower release of TD in comparison with CTS/XG based formulations. Meanwhile, increasing DD resulted in a decrease of drug release. In addition, TD release from XGDS matrices was faster at pH (6.8) than at acidic pH (1.2). The matrix tablets based on CTS/XGDS4 (DD = 98.08%) were selected as the best candidates compared to the other systems in prolonging drug release. The optimal formulation was found to release 99.99% of TD after 24 h following a non-Fickian type.     

海藻酸钠骨架材料中药物释放的影响因素

目的以海藻酸钠为亲水骨架材料，考察药物从海藻酸钠骨架片中释放的体外影响因素。方法以茶碱为模型药物，采用直接压片法制备了茶碱海藻酸钠亲水骨架片，通过对骨架片膨胀性、吸水性以及溶蚀性的考察，研究了影响药物从海藻酸钠骨架材料中释放的体外因素。结果茶碱海藻酸钠骨架片的释药速率和释药机理与骨架片中海藻酸钠粘度、释放介质pH值、离子强度以及转速均有关。结论海藻酸钠能有效地控制骨架片中药物的释放，是一种优良的亲水骨架材料。     

Relationship Between Gelation Rate of Controlled-release Acetaminophen Tablets Containing Polyethylene Oxide and Colonic Drug Release in Dogs

Purpose. We hypothesized that sufficient gelation of orally administered hydrophilic matrix tablets before they reach the colon could, as a result of continuous erosion of the gelated matrix, prevent the decrease in colonic drug release which normally occurs here. The purpose of this study was to elucidate the effect of gelation of hydrophilic matrices containing polyethylene oxide on colonic drug release in dogs using controlled-release (CR) acetaminophen tablets. Methods. Two types of CR tablets were prepared, a slow gelling tablet (SG) and a rapid gelling tablet (RG) containing an extra highly water soluble filler. In vitro and in vivo performance were examined. Results. SG and RG showed similar drug release behavior in vitro. In oral administration to dogs, the two formulations showed similar gastrointestinal transit, reaching the colon within 2–4 h after oral dosing. Further, they showed similar maximum plasma levels (Cmax) and time to Cmax (Tmax). In contrast, however, the two tablets produced different plasma levels from 2 h post-dosing, with plasma levels of RG higher than those of SG and with smaller individual variation. Directly observed colonic drug release behavior of RG was similar to in vitro drug release, whereas that from SG was suppressed. Conclusions. Colonic drug release is closely related to the gelation of hydrophilic matrix, and rapid gelation provides continuous in vivo drug release.     

Swelling,Erosion, and Release Behavior of PEO/Primaquine Matrix Tablets

Extended-release primaquine tablets were developed using polyethylene oxide (PEO) as a hydrophilic swellable polymer with different amounts and molecular weights (4 × 10⁶ and 8 × 10⁶). Investigations were carried out in order to verify the matrix performance. The evaluated parameters were weight, hardness, thickness, friability, and drug content. The swelling and erosion matrices as well as drug release profile were analyzed under dissolution conditions. The statistical model ANOVA and Tukey-Kramer HSD were considered. The results showed that all formulations provided adequate physical characteristics and a time release about eight hours following a non-Fickian diffusion model. The kinetics of drug delivery was directly related to the synchronization of swelling and erosion matrices. The formulations prepared with high PEO concentrations showed a lower rate of erosion, a slower drug release, and faster rate of swelling, as compared with matrices containing lower PEO concentration.     

Tablet and Capsule Hydrophilic Matrices Based on Heterodisperse Polysaccharides Having Porosity-Independent In Vitro Release Profiles

The purpose of the study was to investigate the release-controlling action of a swellable hydrophilic material based on heterodisperse polysaccharides (HP) in relation to the initial pore structure of the formulations. HP-based granules were produced under carefully controlled conditions and compacted into matrix tablets having equivalent tablet thickness. Quantification of pore structure using mercury porosimetry showed that the tablets had substantially different pore volumes and pore size distributions. Dissolution studies demonstrated that release of a water-soluble model compound, benzamide, from swollen matrices was affected neither by total porosity nor median pore diameter of the initial dry matrix. To extend the concept of porosity-independent release further, HP-based formulations containing either diclofenac sodium or propranolol HCl were contained within hard gelatin capsules in the form of uncompacted granules. This produced a dosage form with a high intraparticulate porosity in the dry state. Equivalent weights of the same formulations were also compacted into tablets. The in vitro release profiles from matrix tablets compacted from any of the formulations did not differ significantly from release profiles obtained when the same materials were contained uncompacted in hard gelatin capsules.     

双氯芬酸钾羟丙基甲基纤维素骨架片体外释药的影响因素

目的考察影响双氯芬酸钾羟丙基甲基纤维素(HPMC)骨架片体外释放的各种因素。方法以HPMC为骨架材料,采用湿颗粒法制备双氯芬酸钾缓释片,考察药物/HPMC比、HPMC黏度、HPMC粒径、释放介质pH、压片压力及桨转速对药物体外释放行为的影响。结果药物/HPMC比、HPMC黏度和释放介质pH显著影响双氯芬酸钾释药速率,HPMC粒径、压片压力和桨转速对双氯芬酸钾释药速率影响较小。结论通过使用合适黏度的HPMC及调节药物/HPMC比可获得具有理想释药行为的双氯芬酸钾HPMC缓释片。     

盐酸地尔硫缓释片的制备及体外释放度

以羟丙基甲基纤维素为凝胶骨架材料 ,以淀粉 糊精混合物及乳糖为填充剂 ,采用湿法制粒压片 ,制备了盐酸地尔硫缓释片 ,并对其释放度进行了测定 .所制备的缓释片在释放 90 %之前的释放符合Higuchi方程 .片剂中羟丙基甲基纤维素的含量及稀释剂的种类与含量对药物的释放速度有较大影响 ,而压片力对药物的释放速度无明显影响 .改变缓释片中羟丙基甲基纤维素的含量及稀释剂的种类可改变药物的释放速度