雷贝拉唑钠树脂复合物的制备及评价

目的制备雷贝拉唑钠树脂复合物,探讨其形成机理并考察其稳定性。方法用静态离子交换法制备雷贝拉唑钠树脂复合物,通过正交设计法优化处方制备工艺;通过光学显微镜观察药物树脂复合物的形态外观;通过X-ray衍射分析、差示扫描量热分析以及红外光谱分析探讨药物树脂复合物的形成机理;通过吸湿平衡曲线评价雷贝拉唑钠树脂复合物的防潮性能;通过破坏性实验评价雷贝拉唑钠树脂复合物的耐酸性能。结果优化所得最佳制备工艺:药物初始浓度为1.0g·L~(-1),药物树脂质量比为1︰3,溶液介质离子强度为0.001mol·L~(-1)的氢氧化钠溶液,制备温度为30℃。经红外光谱分析、X-ray衍射和DSC分析,药物树脂复合物所载药物是以化学键的形式结合到离子交换树脂上的。雷贝拉唑钠树脂复合物也具有一定的防潮和耐酸性能。结论雷贝拉唑钠树脂复合物是通过化学键形成的,且在一定程度上能够提高药物的稳定性。     

更昔洛韦药物-树脂复合物的体外释药动力学研究

目的制备更昔洛韦药物-树脂复合物并对其体外释药动力学进行考察。方法考察更昔洛韦药物树脂在不同释放介质、不同离子浓度及不同温度下的释药动力学。结果确定更昔洛韦药物树脂体外释药控制在37℃下,以0．1mol·L^-1HCl为释放介质进行释放度考察,其体外释药行为符合Viswannathan方程。结论体外释药动力学研究表明,更昔洛韦药物树脂的释药行为与释放介质中的离子种类及温度有关,离子强度对释药行为的影响不大。     

醇-水介质中离子交换法制备盐酸小檗碱树脂复合物

目的利用醇-水介质中离子交换制备盐酸小檗碱(berberine hydrochloride,BH)树脂复合物,考察其体外药物释放。方法测定盐酸小檗碱在乙醇-水混合溶剂中的溶解度,采用动态和静态法载药。以乙醇-水(体积比为3∶2)为溶剂,将阻滞材料Eudragit RL100和药物同时溶解并载入Amberlite IRP64弱酸型离子交换树脂形成调释型药物-树脂复合物,用差示扫描量热(DSC)、X-射线粉末衍射(XRD)和傅里叶红外光谱分析(FTIR)分析方法表征复合物,考察阻滞材料用量和释放介质对药物释放的影响。结果溶剂中乙醇-水的体积比为3∶2时,盐酸小檗碱溶解度最高。降低动态法的流速,可提高药物利用率;增大药物浓度,可使饱和时间点提前。XRD、DSC和FTIR分析结果显示,药物与离子交换树脂形成复合物。阻滞材料Eudragit RL100用量增加,药物释放缓慢。药物释放受介质pH影响,酸性条件下释药速率快。结论在乙醇-水混合溶剂中,采用一步法可同时载阻滞材料和药物,得到具有适宜释放特征的盐酸小檗碱-离子交换树脂复合物。     

双氯芬酸钠药物树脂复合物的体外释放特性

目的:制备双氯芬酸钠药物树脂复合物,对其体外释药动力学进行考察。方法:采用不同交联度的离子交换树脂以静态法制备双氯芬酸钠药物树脂复合物并对双氯芬酸钠药物树脂复合物释放的影响因素进行考察。结果:随着树脂交联度的减小,树脂对双氯芬酸钠的载药速率变快,载药量增加。体外释药动力学研究表明,双氯芬酸钠药物树脂的释药速率随着温度的升高和溶出介质中离子强度的增大而加快;而且与树脂本身性质也有关,释药速率随着树脂交联度和粒径的减小而增大;双氯芬酸钠药物树脂的释放为pH依赖型。结论:双氯芬酸钠药物树脂的释药速率与释放温度、溶出介质的离子强度和pH值及树脂交联度和粒径有关。     

难溶性药物布洛芬药物树脂复合物的制备及其体外释放研究

目的:制备布洛芬药物树脂复合物,并考察其体外释药动力学。方法:将布洛芬制备成可溶性的钠盐,采用不同交联度的离子交换树脂为载体以静态法制备布洛芬树脂复合物,并对布洛芬树脂复合物释放的影响因素进行考察。结果:随着树脂交联度的减小,树脂对布洛芬的载药速率变快,载药量增加。体外释药动力学研究表明,布洛芬药物树脂的释药速率随着释放介质离子强度的增加,温度的升高,以及树脂交联度和粒径的减小而加快;且布洛芬药物树脂的释放为pH依赖型。结论:采用离子交换树脂为载体制备的布洛芬树脂复合物具有一定的缓释特征。     

盐酸地尔硫药物树脂的体外释药动力学

目的制备盐酸地尔硫药物树脂复合物并对其体外释药动力学进行考察。方法以静态交换法制备了盐酸地尔硫药物树脂复合物并对盐酸地尔硫药物树脂在不同释放介质(去离子水、0.15 mol.L-1NaCl1、mol.L-1NaCl、0.15 mol.L-1HCl、0.15 mol.L-1KCl溶液)中的释药动力学进行了考察。结果体外释药动力学研究表明,盐酸地尔硫药物树脂的释药速率随着释放介质中离子强度的增大、温度的升高而加快、且释药速率与反离子种类有关。结论盐酸地尔硫药物树脂的释药速率与释放介质的离子强度、反离子种类、介质温度有关。     

阿昔洛韦药物树脂复合物体外释药动力学的研究

目的:制备阿昔洛韦药物树脂复合物并对其体外释药动力学进行考察。方法:以静态交换法制备了阿昔洛韦药物树脂复合物并对阿昔洛韦药物树脂在不同溶出介质中的释药动力学进行了考察。结果:体外释药动力学研究表明,阿昔洛韦药物树脂的释药速率随着溶出介质中离子强度的增大、温度的升高而加快,且释药速率与反离子种类有关。结论:阿昔洛韦药物树脂的释药速率与溶出介质的离子强度、反离子种类和温度有关。     

夏天无总生物碱阳离子树脂复合物的体外释放特性

目的制备夏天无总生物碱树脂复合物并对其指标性成分进行体外释药动力学考察。方法静态交换法制备夏天无总生物碱树脂复合物,以原阿片碱、延胡索乙素为指标性成分,对夏天无总生物碱树脂复合物在不同温度(37、45℃)、不同离子强度释放介质(去离子水、0.15 mol.L-1NaCl、0.6 mo.lL-1NaCl)、不同反离子溶液(0.15 mo.lL-1NaCl、0.15 mol.L-1KCl、0.15 mol.L-1盐酸)中的释药动力学进行了考察。结果体外释药动力学表明,夏天无总生物碱树脂复合物中原阿片碱和延胡索乙素的释药速率随温度的升高而加快,随溶出介质中的离子强度的增大而增大,且释药速率随反离子离子半径增大而减慢(K+相似文献   

盐酸氨溴索药物树脂复合物体外释药动力学的研究

目的制备盐酸氨溴索药物树脂复合物并对其体外释药动力学进行考察。方法以静态 ,动态交换法制备了盐酸氨溴索药物树脂复合物并对盐酸氨溴索药物树脂在不同溶出介质 (去离子水、0 1 5mol·L-1NaCl、1mol·L-1NaCl和 0 1 5mol·L-1HCl以及 0 1 5mol·L-1KCl溶液 )中的释药动力学进行了考察。结果体外释药动力学研究表明 ,盐酸氨溴索药物树脂的释药速率随着树脂粒径的减小 ,溶出介质中离子强度的增大 ,温度的升高而加快 ,且释药速率与反离子种类有关。结论盐酸氨溴索药物树脂的释药速率与树脂粒径 ,溶出介质的离子强度 ,反离子种类 ,温度有关。     

马来酸卡比沙明药物树脂复合物的制备优化及评价

目的制备马来酸卡比沙明药物树脂复合物,筛选最佳制备条件,并考察其理化性质、药物释放及掩味效果。方法动态法制备复合物,响应面法优化筛选药液流速、质量浓度及洗脱时间对药物利用率(DA)和树脂载药量(DL)的影响。用差示扫描量热法(DSC)及傅里叶变换红外光谱(FTIR)分析其形成机理,并考察其释放及掩味效果。结果通过Box-Behnken响应面法进行优化后选择药液质量浓度为7.97mg·mL-1,药液流速为1.35mL·min-1,洗脱时间为114.38min,得到实际药物利用率为85.75%,树脂载药量为1.035g·g-1。经DSC与FTIR进行理化性质分析表明复合物为无定型态。模拟胃肠道释放实验证明其仅在消化道离子丰富的环境中释放,且苦味实验证明其掩味效果明显。结论动态法制备药物树脂复合物能够满足实际生产中高药物利用率和高载药量的要求,同时优化的药物树脂复合物掩味效果明显,能提高药物顺应性。     

Novel interpenetrated polymer network microbeads of natural polysaccharides for modified release of water soluble drug: in-vitro and in-vivo evaluation

Objectives The objective of this work was to prepare novel interpenetrating polymer network (IPN) microbeads of tamarind seed polysaccharide and sodium alginate for controlled release of the water soluble drug, diltiazem hydrochloride. Methods The diltiazem‐Indion 254^® (a cation exchange resin) complex was prepared and the resulting complex was entrapped within IPN microbeads prepared by ionotropic gelation and covalent crosslinking. Microbeads were characterized by scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, X‐ray diffraction and Fourier transform infrared spectroscopy (FTIR) analyses, and evaluated for swelling, in‐vitro release and preclinical pharmacokinetics. Key findings The unformulated drug showed complete dissolution within 60 min, while drug release from diltiazem‐ion‐exchange resin complex was extended for 2.5 h but IPN microbeads extended the release for longer period. The ionically crosslinked microbeads released the drug for 6 h, while dual crosslinked microbeads extended the release for 9 h. The microbeads containing a higher amount of glutaraldehyde released the drug very slowly. The results of in‐vivo pharmacokinetics of pure drug and drug‐loaded IPN microbeads showed that the microbeads demonstrated prolonged release supporting the findings of in‐vitro studies. Conclusions Prepared IPN microbeads showed prolonged in‐vitro and in‐vivo release for diltiazem, indicating that this IPN would be a versatile delivery system for water soluble drugs.     

Drug loading and release properties of ion-exchange resin complexes as a drug delivery matrix

Complexes of ion-exchange resins and dextromethorphan (DM), a model drug, were prepared using different methods including a batch and a column method with different functional groups, ion-exchange capacity, degree of crosslinking, and resin particle size. Drug loading efficiency, release profiles, and scanning electron micrographs were also investigated. Most of the functional groups of resins were loaded with DM after the completion of a double batch method and it was recommended for drug loading into the ion-exchange resin. Using a column method, drug loading could be monitored by simply measuring changes in the pH of the reaction medium since as complex formation reached completion, the pH returned to the initial pH of the eluent due to the limited amount of functional groups available for the exchange. DM could be loaded up to the ratio of 3 (drug): 1 (resin), depending on the physicochemical properties of the resin. As the crosslinking ratio and particle size increased, the drug loading and release rate decreased due to the reduced effective diffusion coefficient and surface area. Assuming that the resin particles are uniform spheres of radius r, release mechanism was evaluated using plots of a Bt-t relationship, where B (=pi(2)D(i)/r(2)) and t are the rate constant and time, respectively. D(i) represents the effective diffusion coefficient of DM inside the resin. The Bt-t plots displayed a straight line indicating that the diffusion of DM in the resin matrix is the rate-controlling step.     

Ketoconazole ion-exchange fiber complex: a novel method to reduce the individual difference of bioavailability in oral administration caused by gastric anacidity

Water insoluble faintly alkaline drugs often have potential absorption problem in gastrointestinal tract in oral administration for patients with gastric anacidity. The purpose of the present study is to develop a novel method to improve the absorption of the water insoluble faintly alkaline drug in peroral administration. This method is based on ion exchange of ion-exchange fibers. Water-insoluble faintly alkaline drug ketoconazole was used as a model drug. Ketoconazole and the active groups of the ion-exchange fibers combined into ion pairs based on the acid-base reaction. This drug carrier did not release drugs in deionized water, but in water solution containing other ions it would release the drugs into the solution by ion exchange. Confirmed by the X-ray diffraction and the differential scanning calorimetry (DSC), the ketoconazole combined onto the ion-exchange fibers was in a highly molecular level dispersed state. The improved dissolution of ketoconazole ion-exchange fiber complexes is likely to originate from this ketoconazole’s highly dispersed state. Furthermore, due to this ketoconazole’s highly dispersed state, ketoconazole ion-exchange fiber complexes significantly decreased the individual difference of absorption in oral administration of ketoconazole caused by the fluctuation of the acid degree in the gastric fluid.     

Ion-exchange resins as drug delivery carriers

There are many reports in the literature referring to the utilization of drug bound to ion-exchange resin (drug–resinate), especially in the drug delivery area. Ion-exchange resin complexes, which can be prepared from both acidic and basic drugs, have been widely studied and marketed. Salts of cationic and anionic exchange resins are insoluble complexes in which drug release results from exchange of bound drug ions by ions normally present in body fluids. Resins used are polymers that contain appropriately substituted acidic groups, such as carboxylic and sulfonic for cation exchangers; or basic groups, such as quaternary ammonium group for anion exchangers. Variables relating to the resin are the exchange capacity; degree of cross-linking, which determines the permeability of the resin, its swelling potential, and the access of the exchange sites to the drug ion; the effective pK_a of the exchanging group, which determines the exchange affinity; and the resin particle size, which controls accessibility to the exchange ions. In this review, the properties of ion-exchange resins, selection of drugs that lend themselves to such an approach, selection of the appropriate resin, preparation of drug–resinate, evaluation of drug release, recent developments of drug–resinates, and applications are discussed. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:3886–3902, 2009     

Formulation and development of taste masked fast-disintegrating tablets (FDTs) of Chlorpheniramine maleate using ion-exchange resins

Context: Masking of bitter taste of drug for better patient compliance.

Objective: The objective of this research was to mask the bitter taste of Chlorpheniramine maleate using cation exchange resins.

Materials and methods: Different cation exchange resins were used for taste masking. The drug resin complexes (DRC) were prepared by batch process. Complexes of ion-exchange resin and Chlorpheniramine maleate were prepared by taking drug: resin ratios 1:1, 1:2, 1: 3 and 1:4 (w/w). The optimum drug: resin ratio and the time required for maximum complexation was determined. The drug resinates were evaluated for the drug content, taste, drug release, FTIR, DSC and X-ray diffraction (PXRD).

Results and discussion: The X-ray diffraction study confirmed the monomolecularity of entrapped drug in the resin beads. The taste evaluation depicted the successful taste masking of Chlorpheniramine maleate with DRCs. Fast disintegrating tablets (FDTs) were developed depending upon percent complexation, release study at salivary and gastric pH, taste evaluation; Chlorpheniramine maleate: Indion-234 complex of ratio 1:2 was used to develop and formulate FDTs. The drug release of 94.77% in 30?min was observed from FDTs.

Conclusion: The Effective taste masking can be obtained from DRC that can be formulated as FDTs for better patient compliance.     

Formulation Design,Optimization and Pharmacodynamic Evaluation of Sustained Release Mucoadhesive Microcapsules of Venlafaxine HCl

The objective of present research work was to design and characterize the venlafaxine HCl-loaded sodium alginate-based mucoadhesive microcapsules by ionic gelation technique using HPMC K100M as mucoadhesive polymer. The Placket-Burman Design was applied for preliminary screening of the formulations and systematic optimization by using Box-Behnken Design. The prepared microcapsules were characterized for drug content, entrapment efficiency, micromeritic properties, particle size, swelling index, mucoadhesive strength, in vitro drug release and in vivo antidepressant activity. FTIR and differential scanning calorimetry studies showed no incompatibility. Surface morphology studies revealed spherical nature of the prepared microcapsules. In vitro drug release studies revealed sustained release by diffusion mechanism. Further, the microcapsules were effective in reducing the depression induced by forced swimming test in Sprague-Dawley rats compared to the pure drug. The microcapsules were found to be stable under accelerated stability conditions, which suggest them as better alternative delivery systems for enhanced therapeutic efficacy of antidepressant drug, venlafaxine HCl.     

Effect of ionic crosslinking on the drug release properties of chitosan diacetate matrices

Chitosan diacetate (CDA) was prepared by alkylating the amino moieties of chitosan with mono-iodoacetic acid. Subsequently, CDA was cross-linked with Al3+, Zn2+, and Ca2+ ions to yield three ionotropically crosslinked polymeric matrices. These composite matrices were characterized employing infrared spectroscopy (IR) and differential scanning calorimetry (DSC). Subsequently, they were loaded with caffeine, as a model drug, and were assessed as sustained release carriers by evaluating their caffeine release profiles. Interestingly, only CDA-Zn2+ complex sustained the release of caffeine effectively in a zero-order manner. The drug release and thermal behavior of the tested matrices agree with the relative strength of the ionic or coordination character of the bonds. This, in turn, depends on the position of the complexing ions on the electrophilic softness/hardness scale.