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。     

去甲斑蝥素缓释片的处方优化及其体外释药特性研究

目的:优化去甲斑蝥素缓释片制备处方及考察其释药特性。方法:以羟丙基甲基纤维素(HPMC)为骨架材料制备去甲斑蝥素亲水凝胶缓释骨架片;以HPMC用量(A)、乳糖用量(B)、乙醇浓度(C)、乙醇用量(D)为因素,以体外释放度综合评分值为指标筛选缓释片的最佳处方并考察其累积释药率。结果:缓释片的最佳处方为A12g、B1.5g、C90%、D10mL;所制缓释片2、6、12h的累积释药率分别为(30.63±1.03)%、(51.70±1.51)%、(89.25±1.04)%,药物释放机制为扩散和骨架溶蚀的协同作用。结论:优化处方制备的去甲斑蝥素缓释片可以达到预期缓释效果。     

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。     

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。     

奥沙西罗亲水凝胶骨架片制备及体外释药特性研究

目的制备奥沙西罗亲水凝胶骨架缓释片,考察处方、工艺以及释放条件对体外释药行为的影响,解析其机理。方法以羟丙甲纤维素(HPMC)为骨架材料,乙基纤维素(EC)为阻滞剂,采用湿颗粒压片法制备奥沙西罗亲水凝胶骨架片,考察HPMC用量、HPMC黏度、EC用量、制备方法、压片压力、释放介质及转速对奥沙西罗骨架片体外释药的影响。结果奥沙西罗骨架片体外释药符合Higuchi方程,药物释放机制是骨架溶蚀和药物扩散的综合效应;HPMC用量与黏度、阻滞剂用量、制备方法、压片压力对释放速率均有显著性影响;释放介质的pH值及转速对释放速率无显著性影响。结论调整处方HPMC用量可制得12 h给药1次的骨架缓释片。     

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。     

阿昔莫司缓释片的体外释放度及释放机制的初步研究

目的：研制凝胶骨架型阿昔莫司缓释片，考察其体外释放度，并对药物的释放机制进行初步研究。方法：以羟丙基甲基纤维素(HPMC)为骨架材料，将阿昔莫司制成凝胶骨架型缓释片，考察HPMC种类及用量、填充剂种类及用量和制备工艺等因素对阿昔莫司缓释片体外释放速率的影响。结果：HPMC的种类、用量和片剂表面积对阿昔莫司体外释放速率有明显的影响；填充剂的种类及制备工艺对释放速率基本无影响；篮法、桨法及转速对释放速率基本无影响。阿昔莫司缓释片的释放机制为非纯Fickian扩散(non—Fickian)机制，即为药物扩散和骨架溶蚀协同作用的结果，其中扩散机制起主要支配作用。结论：用高黏度HPMC作为亲水凝胶骨架片基质能达到较好的缓释作用。     

醋氯芬酸缓释片的研制

目的研制醋氯芬酸缓释片,评价其体外释药性质及释放机制.方法采用不同的高分子材料,按照均匀设计得到不同的处方,制成亲水凝胶骨架片,测定其释放度,并用SAS统计软件进行分析.结果处方R324h释放达95%以上,具有很好的缓释作用,其释放机制符合HixonCrowell方程,为亲水凝胶溶蚀与药物扩散共同作用的结果.结论该制剂体外释药性质主要受HPMCK4M和Carbopol934p的量及压力的影响.     

己酮可可碱缓释片的制备及体外释放度考察

目的制备己酮可可碱缓释片并对其体外释放度进行考察。方法以紫外-分光光度法为分析方法,采用相似因子法对己酮可可碱缓释片体外释放行为进行评价,并对优化处方的释药机制进行探讨。结果 KollidonSR用量、黏合剂种类、薄膜衣增加质量和释放介质的pH值对药物释放无明显影响,HPMC规格、用量和转速对药物释放有显著性影响,片剂合格范围内的硬度对药物释放几乎无影响,优化处方的释药过程为药物扩散和骨架溶蚀共同作用。结论单独应用HPMC K4M为骨架材料即可制备具有理想释药行为的己酮可可碱缓释片,其释放度符合《中华人民共和国药典》2010年版标准且与进口己酮可可碱缓释片(瑞潘通)相似。     

硝酸异山梨酯缓释片的研制及体外释放度研究

目的:研究硝酸异山梨酯缓释片(亲水凝胶骨架型)的生产工艺,并考察其体外释放特性.方法:根据新的药品标准对体外释放速率的要求,以羟丙甲基纤维素(HPMC)为骨架材料筛选处方.结果:药物释放是骨架膨胀溶蚀和药物扩散作用的综合效应,释放速率受温度影响明显,受压力影响较小.结论:该硝酸异山梨酯缓释片具有工艺简单、成型性好、重现性好等优点,体外释放度符合拟定的释药速率要求.     

硫普罗宁缓释片的制备及体外释放度考察

目的制备硫普罗宁缓释片并对其体外释放度进行考察。方法以HPLC法为分析方法,采用相似因子法评价硫普罗宁缓释片体外释放行为。结果硫普罗宁缓释片的体外释放行为符合Highuchi方程。KollidonSR用量、填充剂的种类与用量及种类对药物的释放速度有较大影响,而硬度和释放介质的离子强度对药物的释放速度无显著影响。结论体外释放度符合缓释制剂要求,可进一步进行体内释药行为考察。     

In Vitro and in Vivo Evaluation of Whole and Half Tablets of Sustained-Release Adinazolam Mesylate

The mechanism of release from sustained-release adinazolam mesylate tablets was assessed by the Higuchi equation and by analysis of drug release profiles through 60% released using the Peppas equation. Computed values of the diffusional exponent, n, ranged from 0.59 to 0.66. Values of n in this range are consistent with a mixed mechanism of release, with diffusion of drug through the hydrated polymer matrix and relaxation of this matrix being the principal processes controlling release. The rate of in vitro drug release was increased for half tablets relative to whole tablets and is attributed to an increase in the surface to volume ratio of half tablets of about 16%. This increase in surface-to-volume ratio of half tablets was reflected by an increase in the constant, k, from the Peppas equation of 20–23% and by an increase in the slope of Higuchi plots of 12–18% for four lots of tablets. In vivo/in vitro relationships from two bioavailability studies were thoroughly evaluated. Using either a linear or a quadratic relationship, an in vivo/in vitro correlation exists for sustained-release adinazolam mesylate tablets.     

Formulation and In vitro assessment of sustained release terbutaline sulfate tablet made from binary hydrophilic polymer mixtures

In the present systematic study, a sustained release of terbutaline sulfate tablet (TBS) was developed and optimized by employing the hydrophilic polymers; chitosan and xanthan gum mixed with sodium bicarbonate as a release modifying agent. This formulation was developed using direct compression technology. In vitro release studies indicated rapid swelling and drug release in the initial period of the acid stage from a matrix composed of chitosan and xanthan gum solely. Addition of sodium bicarbonate to the matrix resulted in sustained drug release. Various formulation factors such as polymer to polymer ratio, polymer viscosity and particle size were altered and their effect on dissolution pattern was illustrated. Manufacturing variables such as compression force and lubricant percentage were investigated and found not to influence the drug release profile of the resulted tablets. The release mechanism follows Korsmeyer-Peppas equation with n value indicating non-Fickian diffusion. The release profiles were analyzed using statistical method (one-way ANOVA) and f₂ metric values and found to be similar to the commercial product Bricanyl^®. Reproducible data were obtained when scale-up of the formulation was performed.     

In vitro characterization and release study of Ambroxol hydrochloride matrix tablets prepared by direct compression

A series of either hydrophilic or hydrophobic polymers were used to prepare controlled release Ambroxol hydrochloride (AMX) matrix tablets by direct compression. Both the compatibility and flow properties of AMX/polymer mixtures were investigated. The effect of the amount and type of polymer on the physical properties and in vitro drug release was studied and compared to commercially available Ambroxol^® SR capsules. A kinetic study of the release profile of AMX from the prepared matrix tablets was performed. All excipients used in the study were compatible with the model drug. AMX/drug mixtures containing sodium alginate (NA) and hydroxypropylmethyl cellulose (HPMC) showed better flow properties than other polymers used in the study. The in vitro drug release studies showed that matrix tablets formulae containing 10% HPMC (S7) or a combination of 30% NA and 5% HPMC (Ah) exhibited a higher ability to control the release of AMX. The kinetic study revealed that a diffusion controlled mechanism prevailed except when carbopol was used. Formula Ah followed a non-fickian diffusion mechanism similar to Ambroxol^® SR capsules. Both formulae S7 and Ah could be considered as potential candidates for formulation of AMX controlled release matrix tablets.     

Dissolution profiles of mesalazine formulationsin vitro

In vitro dissolution profiles of three controlled-release mesalazine formulations were determined at pH 1.0, 6.0 and 7.5. A closed-column type dissolution apparatus was used. A reproducible gradual dissolution profile was seen for Pentasa^® at all pH values. Dissolution starts immediately and is complete after 20 h. Dissolution profiles at pH 1 and pH 7.5 are much alike and dissolution is faster than at pH 6. The behaviour of Asacol^® at different pH values corresponds with the expectations: no release at pH 6 and pH 1, fast release at pH 7.5. Dissolution starts after 1 h and is complete after 3 h. Mesalazine release from Salofalk^® tablets at pH 7.5 and pH 6.0 starts after 2 and 3 h, respectively, and is complete after 5 and 10 h. However, after a long lag-time (10 h) mesalazine is also released from Salofalksu^® tablets at pH 1 and dissolution is complete after 23 h.     

盐酸伪麻黄碱脉冲小片包衣液处方优化

目的制备盐酸伪麻黄碱脉冲控释小片,并对其体外释药情况进行研究。方法制备盐酸伪麻黄碱含药片芯,采用丙烯酸树脂水分散体(Eudragit(RS 30D)制备盐酸伪麻黄碱脉冲控释小片。通过单因素实验考察药物释放的影响因素,确立处方组成,采用正交设计对包衣液处方进行优化。结果当隔离层增质量分数为2%、控释层增质量分数为5%、CMS-Na用量质量分数为25%,脉冲控释小片的时滞为6 h,体外具有脉冲释药特性。结论成功地制备了盐酸伪麻黄碱脉冲控释小片,体外释药符合脉冲释药的要求。     

Effect of binders on the release rates of direct molded verapamil tablets using twin-screw extruder in melt granulation

Conventional manufacturing of pharmaceutical tablets often involves single processes such as blending, granulation, milling and direct compression. A process that minimizes and incorporates all these in a single continuous step is desirable. The concept of omitting milling step followed by direct-molding of tablets utilizing a twin-screw extruder in a melt granulation process using thermoplastic binders was explored. The objective of this study was to investigate the effect of combining hydrophilic binder (HPMC K4M, PEO 1M), and hydrophobic binder (Compritol^® ATO 888, Precirol^® ATO 5) on the release profiles of direct-molded tablets and direct-compressed tablets from milled extrudates using a quality-by-design approach. It was identified that hydrophilic binder type and process significantly affects (p = 0.005) the release profiles of verapamil. Moreover, two-way interaction analysis demonstrated that the combination of process with type of hydrophilic polymer (p = 0.028) and the type of hydrophilic polymer with polymer ratio (p = 0.033) significantly affected the release profiles. The formulation release kinetics correlated to Higuchi release model and the mechanism correlated to a non-Fickian release mechanism. The results of the present study indicated that direct-molded tablets with different release profiles can be manufactured without milling process and through a continuous melt granulation using twin-screw extruder with appropriate thermoplastic binder ratio.     

卡维地洛凝胶骨架缓释片的处方优选与表征

目的 优选12 h内体外缓慢释药的卡维地洛凝胶骨架缓释片的处方工艺并进行表征。方法 以2种型号的HPMC为骨架材料,通过正交试验法,优选处方工艺并验证,考察制剂在4种介质中12 h内的体外释放度,利用X-射线衍射法和红外光谱法分析药物的存在状态。结果 最佳处方为卡维地洛7.5%,单硬脂酸甘油酯30%,HPMC K4M+E50占片重25%,HPMC K4M∶E50的比例为2∶1,乳糖占15%,硬度为3.5 kg;制剂在pH 1.2的介质中释药最快,12 h内达到90%以上,体外释药稳定（RSD<1.5%,n=3）,符合Higuchi动力学方程,属于骨架溶蚀型释药系统;药物在片中以部分晶体存在,原辅料之间没有新键生成。结论 该制备工艺简单,重复性良好,在12 h内具有良好的体外缓释特征。     

鱼腥草素钠缓释片的制备及体外释放特性研究

目的制备鱼腥草素钠缓释片,并考察其体外释放特性。方法分别采用羟丙基甲基纤维素（HPMC）、联合应用HPMC与乙基纤维素（EC）作为骨架材料制备鱼腥草素钠缓释片,以累积释放度为指标,评价其体外释放特性。结果HPMC黏度及用量、EC用量对药物的释放有较大影响,填充剂对药物的释放几乎无影响。缓释片释药结果符合Higuchi方程。结论所制备的鱼腥草素钠缓释片缓释性能良好,其释放机制为非Fick’s扩散。     

Natural gum as mucoadhesive controlled release carriers: evaluation of Cefpodoxime Proxetil by D-Optimal design technique

Abstract

The present study deals with the development of mucoadhesive controlled release tablets of Cefpodoxime Proxetil to increase the gastric residence time and thus prolong drug release, reduce dosing frequency and improve oral bioavailability. Tablets were prepared using sodium alginate and karaya gum, a natural polymer, with a synthetic polymer hydroxypropylmethylcellulose (K100LV) and Karaya gum with HPMC K100LV in various ratios to optimize the drug release profile using D-Optimal technique. Pre- and post-compression parameters of tablets prepared with various formulations (S1–S9, C1–C9) were evaluated. The FTIR and DSC studies revealed that no physiochemical interaction between excipients and drug. The formulation S7 showed prolonged drug release, and the mechanism of drug release from the optimized formulation was confirmed using the Korsmeyer–Peppas model to be non-Fickian release transport and n value was found 0.605 indicating both diffusion and erosion mechanism from these natural gums. The optimized formulation showed mucoadhesive strength >35?g. An in vivo study was performed on rabbits using an X-ray imaging technique. The radiological evidence suggests that the tablets adheres (more than 10 hours) to a rabbit’s stomach. No significant changes were found in the physical appearance, drug content, mucoadhesive study and in vitro dissolution pattern after storage at 40?°C/75% relative humidity for 3 months.