盐酸维拉帕米脉冲控释片的研究

目的:制备适于临睡前服用、间隔4 h 后于次日凌晨释放出治疗药物的脉冲控释片。方法:以均匀设计优化盐酸维拉帕米压制包衣片的处方组成,体外溶出度测定、体内γ-闪烁扫描示踪考察药物释放滞后时间(T_lag) ,在家犬、人体内的药代动力学研究,考察脉冲控释片在体内控时效果。结果:均匀设计得出的多元线性回归方程优化筛选了控时3,4 ,5 h 的脉冲片处方,体外脉冲控时4 h 的IV 型脉冲片,在家犬体内和体外控时3 h 的III型脉冲片在受试者体内均实现给药后4 h 脉冲释放。结论:脉冲控释片仅改变了制剂的释药开始时间,而对药物的峰浓度、生物利用度等无影响,实现设计中的脉冲释放,为防治高血压的凌晨发作提供了良好的剂型选择。     

结肠定位释药瓜尔胶/乙基纤维素包衣小丸

体外研究瓜尔胶/乙基纤维素混合包衣小丸的结肠靶向性。以5-氟尿嘧啶为模型药， 采用流化包衣技术以瓜尔胶/乙基纤维素混合物的水/醇混悬液对载药小丸进行喷液包衣。瓜尔胶/乙基纤维素混合包衣小丸的释药行为取决于包衣处方中瓜尔胶与乙基纤维素的比例和包衣厚度。分别以混合包衣液中瓜尔胶与乙基纤维素的比例及包衣增重为自变量， 以T₅和T₉₀（药物释放5%和90%所需要的时间）为效应， 进行3×4析因设计/效应面优化， 筛选较优处方。结果表明随着乙基纤维素在衣层中所占比例的增大及包衣厚度的增加， 药物释放时滞增加。当瓜尔胶与乙基纤维素的比例在0.2~0.7， 并且包衣增重在250%~500%时， T_5%为5.1～7.8 h， T_90%为9.8～16.3 h。并且在释药时滞之后， 进入模拟结肠微菌群酶解作用的释放环境中(pH 6.5)药物释放速度加快， T_90%缩短到9.0～14.5 h。由此可以看出适当的瓜尔胶/乙基纤维素混合衣层既可以保护药物顺利通过上消化道而不释放， 达到结肠后药物开始释放， 并且可在结肠微菌群的酶解作用下加速药物的释放， 实现结肠定位释药的目的。     

复方丹参pH依赖型延迟释药微丸在家犬体内的药效动力学

目的制备复方丹参pH依赖型延迟释药微丸填充胶囊并进行家犬体内药效动力学研究。方法分别用HPMC，Eudragit L-30D-55，Eudragit L100/S100 (1∶6)包衣制备pH依赖型延迟释药微丸，测定体外释放曲线，并用血清药理学方法进行家犬体内的药效动力学研究。结果制备了复方丹参pH依赖型延迟释药微丸，体外溶出曲线呈pH依赖特征。单剂量给药后自制速释片R的药效动力学参数T_max为0.58 h，E_max为34.63%，延迟释药胶囊T1和T2的T_max分别延长至2.42和3.17 h，E_max分别降低至13.57%和14.52%，相对生物利用度分别为99.3%和133.6%。多剂量给药后自制速释片R波动度DF 7.32，延迟释药胶囊T1和T2的波动度DF 3.40和3.03。结论复方丹参pH依赖型延迟释药胶囊体外释放具有pH依赖特征，体内具有明显的延迟释药作用，多剂量达到稳态时，药效动力学波动系数低于普通片。     

基于Keap1/Nrf2/HO-1通路汉黄芩素7-O-β-D-乙基葡萄糖醛酸苷体外抗氧化应激作用研究

目的 探讨汉黄芩素 7-O-β-D-乙基葡萄糖醛酸苷（WODE）对脂多糖（LPS）诱导的小鼠巨噬细胞（RAW264.7）的抗氧化应激作用及机制。方法 MTS法检测WODE（2.5、5.0、10.0、20.0、40.0、80.0、160.0 μmol·L^-1）对RAW264.7细胞活力的影响；体外培养RAW264.7细胞，WODE（10、20、40 μmol·L^-1）或地塞米松（1 μmol·L^-1，阳性药）预处理1 h，再给予LPS刺激24 h（造模过程不再加药），对照组不加 LPS 和受试物，模型组只给予 LPS 刺激；荧光探针检测胞内活性氧（ROS）水平；Griess反应测定细胞上清液中 NO 生成量；ELISA 检测细胞上清液中肿瘤坏死因子-α（TNF-α）和白细胞介素-6（IL-6）的分泌；实时荧光定量 PCR（qRT-PCR）法检测细胞内诱导型一氧化氮合成酶（iNOS）、环氧化酶-2（COX-2）、白细胞介素-1β（IL-1β）、醌氧化还原酶1（NQO-1）、超氧化物歧化酶-1（SOD-1）的mRNA表达水平；Western blotting法检测细胞核因子E2相关因子2（Nrf2）和血红素加氧酶-（1 HO-1）蛋白表达水平；免疫荧光染色法检测细胞内Kelch ECH相关蛋白（1 Keap1）表达水平。结果 与对照组比较，WODE浓度小于40 μmol·L^-1时，细胞存活率没有明显变化；浓度大于80 μmol·L^-1时，细胞存活率下降，但未见统计学差异。与模型组比较，WODE 10、20、40 μmol·L^-1组 ROS水平显著降低（P＜0.01）；20、40 μmol·L^-1 组 NO 释放显著降低（P＜0.05、0.01）；40 μmol·L^-1 组 iNOS mRNA 表 达 水 平 显 著 降 低（P＜0.01）；10、20、40 μmol·L^-1 组 COX-2 和20、40 μmol·L^-1组IL-1β mRNA表达水平显著降低（P＜0.05、0.01）；10、20、40 μmol·L^-1组TNF-α和IL-6的释放受到显著抑制（P＜0.01）；10、20、40 μmol·L^-1组NQO-1 mRNA表达水平显著升高（P＜0.01），40 μmol·L^-1组SOD-1 mRNA表达水平显著升高（P＜0.01）；10、20、40 μmol·L^-1组Keap1蛋白表达水平显著降低（P＜0.01）；10、20、40 μmol·L^-1组HO-1蛋白和mRNA表达水平显著提高（P＜0.05、0.01）；20、40 μmol·L^-1 组 Nrf2 蛋白和 40 μmol·L^-1 组 Nrf2 mRNA 表达水平显著增加（P＜0.01）。结论 WODE 对 LPS 诱导的RAW264.7细胞的氧化应激具有抑制作用，其作用机制可能与调控Keap1/Nrf2/HO-1信号通路相关。     

温敏性吲哚美辛/β-环糊精包合物的制备及体外评价

目的合成兼具温敏性及药物包合能力的新型药物载体聚(N-异丙基丙烯酰胺)-β-环糊精(PNIPA-β-CD)，以吲哚美辛为模型药物，考察该载体的释药行为。方法末端带羧基的PNIPA与改性后的环糊精衍生物在1-(3-二甲氨基丙基)-3-乙基-碳二亚胺(EDC)的作用下缩合，得到PNIPA-β-CD，采用冻干法制备吲哚美辛/PNIPA-β-CD包合物。红外、¹H NMR和DSC表征载体的结构及包合物的形成；用分光光度法测定载体材料的LCST，并进行包合物体外释药研究。结果PNIPA-β-CD在35 ℃发生相转变，吲哚美辛/PNIPA-β-CD包合物的载药量为5.8％，药物与载体摩尔比为0.97∶1。体外释放研究表明吲哚美辛/PNIPA-β-CD包合物在37 ℃的释药比其在25 ℃的释放要慢，在LCST以上具有一定的缓释作用。结论该载体既具有温敏性，又具有药物包合作用，并且在体温条件下具有缓释作用，是一种新型的温敏性药物载体。     

新型非环核苷膦酸L-氨基酸酯类化合物的设计、合成与抗乙型肝炎病毒活性

设计合成具有抗乙型肝炎病毒活性的非环核苷膦酸双L-氨基酸酯系列衍生物。以adefovir dipivoxil为先导化合物， 根据核苷L-氨基酸酯前药提高生物利用度及抗病毒活性的研究结果对先导化合物进行结构优化， 设计并合成一系列新型非环核苷膦酸双L-氨基酸类化合物， 确定其结构， 并通过测定其对HepG2 2.2.15细胞分泌的HBV-DNA的抑制作用评价其体外抗病毒活性。结果发现8个adefovir双L-氨基酸类化合物可显示不同程度活性， 其中化合物11的抗病毒活性最强、 选择性指数最高(EC₅₀ 0.095 2 μmol·L^-1, SI 69523)。以上研究提示L-氨基酸酯策略可适用于非环核苷膦酸的前药修饰， 以期发现有效抗HBV药物。     

盐酸地尔硫爆破型脉冲控释片研究

目的以盐酸地尔硫为(diltiazem hydrochloride,DIL)模型药物,研制爆破型脉冲控释片并考察其体内外脉冲释药特性。方法以乙基纤维素和丙烯酸树脂(Eudragit L)为包衣材料,采用薄膜包衣法,制备含盐酸地尔硫60 mg的脉冲控释片。通过体外释放度实验,考察了处方因素对脉冲控释片体外释放的影响;通过吸水实验确定了脉冲控释片的释药机理;以高效液相色谱法测定8名受试者的体内血药浓度,研究脉冲控释片的体内药代动力学和生物利用度。结果片芯处方、包衣组成和包衣厚度影响盐酸地尔硫的脉冲释放。该制剂在体外延迟释放时间T₁₀为4.4 h,释放至最大的时间T_rm为8.0 h,脉冲释放时间T_rm-10为3.6 h;其体内的延迟释放时间T_lag为4.9 h,达峰时间T_max为8.0 h,从开始释放到达峰的时间T_psi为3.1 h。脉冲控释片的相对生物利用度为105%。结论盐酸地尔硫爆破型脉冲控释片在体内外都具有脉冲释放特性。     

麝香保心pH依赖型梯度释药微丸的研究

目的制备麝香保心pH依赖型梯度释药微丸并进行体内外考察。方法分别以HPMC,Eudragit L-30D-55和Eudragit L100-Eudragit S100(1∶5)为包衣材料制备pH依赖型梯度释药微丸,并进行体外释放度、胃肠道转运和体内药代动力学研究。结果冰片和人参总皂苷体外释放度的f₂值为79.6,3种包衣微丸分别在胃、十二指肠和空回肠部崩解,由3种微丸组成的缓释胶囊中冰片的T_max与原丸剂相近,而C_max明显降低,相对生物利用度为96%。结论 缓释胶囊中的冰片和人参总皂苷在体外可同步缓释,在体内具有pH依赖性崩解溶散的特征,冰片作为指标性成分具有梯度缓释的药代动力学特点。     

化学—酶法立体控制合成光学纯L-羟基苯丙氦酸的新方法

Optically pure L-3(2-hydroxyphenyl) alanine(L-o-tyrosine ,Ⅲa,),L-3-(3-hydroxyphenyl) alanine(L-m-tyrosine,Ⅲb )and L-3-(4-hydroxyphenyl )alanine(L-p-tyrosine,Ⅲc )were synthesized by the stereocontrolled amination of corresponding hydroxycinnamic acld(Ⅱ)catalyzed by L-phenylalanine ammonia-lyase(PAL,EC4.3.1.5 )contained in Rhodoterula rubramycelium. The amination of compound Ⅱ was completed in aqueous ammonia solution( 6.4mol·L^-1,pH10.5, 30℃) with the conversion of 74.9%(Ⅱa),21.1%(Ⅱb)and 20.6%(Ⅱc)respectively.The absolute configuration of the products Ⅲa～c were confirmed by circular dichroism(CD),and chiral high-performance ligand exchange chromatography(HPLEC)showed that productsⅢ were optically pure L-isomers.     

5-氨基水杨酸结肠定位给药pH与时间同时控释小丸的制备与体外释放

目的:用水分散体包衣技术制备5-氨基水杨酸 (5-ASA) 结肠定位小丸给药系统.方法:以Eudragit(R) RL30D作为时间控释包衣内层,Eudragit(R) S水分散体作为pH控释外层,三乙酸甘油酯为增塑剂,使用流化床包衣设备,制备pH值与时间同时控释的小丸,用释放度测定法研究小丸在不同pH介质中的释放度.结果:小丸在模拟胃酸情况下不释药,在变换pH 7.5条件下9h内释药完全.Eudragit(R) S层保证小丸安全通过胃;而药物释放速度是由丸心、Eudragit(R) RL30D时间控释层来控制.利用小肠相对恒定的转运时间(3～4h)和小肠末端高pH(7～8),及不同Eudragit(R)聚合物的pH性质制备了较可靠的多剂量结肠给药系统.结论:通过调整内外层包衣厚度可制备5-ASA结肠定位释放小丸.     

新型茶碱口服结肠靶向给药系统的体内动力学

目的研究以时间为释药开关的结肠靶向给药系统。方法以非pH依赖型聚丙烯酸树脂Eu dragit NE 3 0D为膜材 ,制备茶碱薄膜衣片 ;用HPLC法进行体内血药浓度分析 ;以γ 闪烁照相研究该制剂体内胃肠道的转运情况。结果本制剂与参比制剂主要药代动力学参数分别为 :tlag( 8 67± 1 0 4 )h、( 0 67± 1 1 5 )h ;Cmax( 5 2 5± 1 2 1 )mg/L、( 4 0 9± 1 2 5 )mg/L ;AUC0 2 6 ( 2 7 5 0±7 2 0 )mg·h/L、( 3 9 0 4± 1 0 4 3 )mg·h/L ;体内γ 闪烁照相研究表明 ,体外 6 5h释放的制剂口服8 0h后到达升结肠处开始释药 ,且体内释药与体外释药有一定的相关性。结论本制剂能达到结肠靶向释药的设计要求     

In vitro evaluation and pharmacokinetics in dogs of guar gum and Eudragit FS30D-coated colon-targeted pellets of indomethacin

A pH- and enzyme-dependent colon-targeted multi-unit delivery system of indomethacin was developed by coating guar gum and Eudragit FS30D sequentially onto drug-loaded pellets in a fluidized bed coater. In vitro studies showed that smaller coating weight gain of guar gum resulted in reduced release lag time t10 (10% release time), but favored degradation by enzymes (galactomannanase). A cumulative weight gain (CWG) of 44% provided sufficient enzymatic sensitivity and protection of the core. Under gradient pH conditions (pH = 1.2, 6.8, 7.4 and 6.5 for 2, 2, 1 and 15 h, respectively), indomethacin was released from Eudragit FS30D-coated pellets quickly after changing pH to 7.4. For guar gum/Eudragit FS30D double-coated pellets, only about 5% of the drug was released after another 1 h, showing retarding effect by guar gum coating. After changing pH to 6.5 and addition of galactomannanase, enzyme-dependent drug release was observed. Pharmacokinetic study in beagle dogs showed that fastest absorption with the smallest Tmax and Tlag was observed for uncoated pellets. The Tmax and Tlag of Eudragit FS30D-coated pellets were postponed to about 2.5 and 1 h, respectively. After a further guar gum coating, Tlag was further postponed to about 2.8 h, about 2 h of additional lag time on the basis of Eudragit FS30D coating. It is indicated that the guar gum/Eudragit FS30D-coated system has potential to be used to deliver drugs to the colon.     

4-氨基水杨酸钠结肠定位包衣片的制备及释放度测定

目的:以多层包衣法制备4-氨基水杨酸钠口服结肠定位系统,并考察其释放度,评价包衣工艺的稳定性。方法:用渗透型和肠溶型丙烯酸树脂依次包衣,制备pH、时间双重依赖的4-氨基水杨酸钠口服结肠定位包衣片;采用紫外分光光度法测定包衣片在不同pH条件下的释放度及3批包衣片在pH=7.4介质中的累积释放度,计算并比较释放参数T50、Td、T80、m。结果:包衣片在pH=6.5介质中12h释药量小于5%,有明显时滞;在pH=7.0、pH=7.4介质中12h内释药量均大于80%,无时滞效应;3批包衣片溶出度参数之间比较均无显著性差异(P>0.05)。结论:以渗透型和肠溶型丙烯酸树脂依次包衣制备的4-氨基水杨酸钠口服结肠定位包衣片具备理想的定位与缓释功能,包衣工艺稳定,重现性好。     

Design,optimization and evaluation of mesalamine matrix tablet for colon drug delivery system

The aim of the present investigation was to develop and evaluate matrix tablet of mesalamine for colonic delivery by using Eudragit RSPO, RLPO and combination of both. The tablets were further coated with different concentration of pH-dependent methacrylic acid copolymers (Eudragit S100), by dip immerse method. The physicochemical parameters of all the formulations were found to be in compliance with the pharmacopoeial standards. The in vitro drug release study was conducted using sequential dissolution technique at pH 1.2 (0.1N) HCl, phosphate buffers pH 6.8 and 7.4, with or without rat cecal content mimicking different regions of gastro intestinal tract. The result demonstrated that the tablet containing Eudragit RLPO coated with Eudragit S100 (1 %) showed a release of 94.91 % for 24 h whereas in the presence of rat cecal content the drug release increases to about 98.55 % for 24 h. The uncoated tablets released the drug within 6 h. The in vitro release of selected formulation was compared with marketed formulation (Octasa MR). In vitro dissolution kinetics followed the Higuchi model via non-Fickian diffusion controlled release mechanism. The stability studies of tablets showed less degradation during accelerated and room temperature storage conditions. The enteric coated Eudragit S100 coated matrix of mesalamine showing promising site specific drug delivery in the colon region.     

氟比洛芬肠溶片的制备及其体外释放度研究

目的:制备氟比洛芬肠溶片并考察其体外释放特性。方法:以乙基纤维素(EC)、甲基丙烯酸共聚物(Eudragit S100)、乳糖为辅料,采用直接压片法制备制剂;考察处方中不同辅料用量对药物释放的影响及其在0.1mol·L-1盐酸溶液(HCl)和pH6.8磷酸盐缓冲液(PBS)中的体外释放特性。结果:以EC0.250g、Eudragit S1000.750g、乳糖3.750g时组成的处方可在HCl中不释放,在PBS中完全释放达94.20%。结论:该制剂处方设计和制备方法可行,其释放行为符合设计要求。     

Preparation and evaluation of Vinpocetine self-emulsifying pH gradient release pellets

The main objective of this study was to develop a pH gradient release pellet with self-emulsifying drug delivery system (SEDDS), which could not only improve the oral bioavailability of Vinpocetine (VIN), a poor soluble drug, but reduce the fluctuation of plasma concentration. First, the liquid VIN SEDDS formulation was prepared. Then the self-emulsifying pH gradient release pellets were prepared by extrusion spheronization technique, and formulation consisted by the liquid SEDDS, absorbent (colloidal silicon dioxide), penetration enhancer (sodium chloride), microcrystalline cellulose, ethyl alcohol, and three coating materials (HPMC, Eudragit L30D55, Eudragit FS30D) were eventually selected. Three kinds of coated pellets were mixed in capsules with the mass ratio of 1:1:1. The release curves of capsules were investigated in vitro under the simulated gastrointestinal conditions. In addition, the oral bioavailability and pharmacokinetics of VIN self-emulsifying pH gradient release pellets, commercial tablets and liquid VIN SEDDS were evaluated in Beagle dogs. The oral bioavailability of self-emulsifying pH gradient release pellets was about 149.8% of commercial VIN tablets, and it was about 86% of liquid VIN SEDDS, but there were no significant difference between liquid SEDDS and self-emulsifying pH gradient release pellets. In conclusion, the self-emulsifying pH gradient release pellets could significantly enhance the absorption of VIN and effectively achieve a pH gradient release. And the self-emulsifying pH gradient release pellet was a promising method to improve bioavailability of insoluble drugs.     

pH依赖—缓释型美沙拉秦结肠靶向小丸的制备与体外评价

以肠溶型和渗透型丙烯酸树脂为包衣材料制备ｐＨ依赖－缓释型美沙拉秦结肠靶向小丸,评价其体外释放特性。结果表明,包衣小丸在０．１ｍｏｌ／ＬＨＣｌ中２ｈ几乎不释放药物,在ｐＨ７．５缓冲液中具有较好的缓释作用。在模拟胃肠道各区段最高的和最低的ｐ变化的释放度试验中,均在对应小肠区段时开始缓慢释药。分别有４０％和７０％的药物进入结肠后释放。优于单独的肠溶或缓释制剂。     

Composite film-coated tablets intended for colon-specific delivery of 5-aminosalicylic acid: using deesterified pectin

Combinations of Eudragit RS and deesterified pectin, polygalacturonic acid (PGA), or its potassium and sodium salts, when applied as a film coat, has a potential value as a colon-specific delivery system. Dispersions of PGA in Eudragit RS were used as the film former for coating of 5-aminosalicylic acid (5-ASA) tablet cores. Drug release behavior was assessed, in vitro, under simulating conditions in term of pH and time to in vivo during their transit to the colon. Negligible drug release occurred during first 5 hr where the coated tablets were in the stomach and small intestine. After that, the pectinolytic enzymes were added into the pH 6.8 medium to simulate the in vivo condition where there is the digestion of bacteria in the colon. The release of 5-ASA from the coated tablets occurred linearly as a function of time. Drug release depended on the composition of the mixed film, as well as the ratio of Eudragit RS to PGA or its salts. The highest drug release from the coated tablets of about 40% was obtained when the ratio of Eudragit RS to potassium salt of PGA was 2.5 to 1. Drug release profiles seemed to conform to the mechanism involving the osmotically driven release and formation of channels in the film caused by dissolution of PGA salts. Channel formation was, in most cases, activated by the presence of pectinolytic enzymes, showing that the PGA in the mixed film was subjected to enzymic breakdown. In conclusion, PGA could be used as an additive in Eudragit RS films to control the release of colonic delivery system.     

多糖凝胶骨架结肠定位给药缓释系统的体外释放研究

目的: 筛选多糖材料作为水凝胶骨架,以达到结肠定位释药目的.方法: 选用海藻酸钠、果胶、壳聚糖、瓜木耳胶与药物混和制粒,灌装肠溶或结肠溶胶囊,考察其在人工胃液,人工肠液及人工结肠液中的释放情况.结果: 难溶性药物的海藻酸钠骨架结肠溶胶囊在人工胃液和小肠液中均不释放,人工结肠液中3 h释药低于30%;果胶骨架肠溶胶囊在人工胃液亦不释药,人工肠液中5 h释药仅为15%.水溶性药物在人工肠液中5 h释放可达50%.结论: 难溶性药物的海藻酸钠/结肠溶胶囊和果胶/肠溶胶囊体外释放度结果符合结肠定位的要求,可以作为建立酶触发体外释放评价方法和体内评价的制剂形式.水溶性药物的果胶/肠溶胶囊是较理想的缓释剂型.