他克莫司温度敏感眼用凝胶的体外释放研究

目的探讨各因素对他克莫司温度敏感眼用凝胶体外释放的影响。方法采用无膜溶出模型,考察释放面积、振荡频率对眼用凝胶溶蚀及药物释放的影响。结果随着释放面积和振荡频率的增加,凝胶溶蚀和药物释放增加。结论药物释放主要取决于凝胶溶蚀。     

地塞米松磷酸钠温度敏感原位凝胶释药与溶蚀行为的影响因素考察

目的:制备泊洛沙姆温度敏感原位凝胶,考察地塞米松磷酸钠(DSP)在其中的释放行为以及影响释放的因素。方法:以PluronicF127和F68为材料,DSP为模型药物制备温度敏感原位凝胶并测定胶凝温度。采用无膜溶出法和HPLC法测定DSP的释放行为;考察释放介质的接触面积、体积、pH值及振荡频率对DSP释放的影响。测定凝胶的溶蚀行为及其对药物释放的影响。结果:胶凝温度随F127浓度增大而升高,释放介质的接触面积、体积、振荡频率对药物的释放速率有显著影响,释放介质的pH对药物释放速率无显著影响。DSP的释放和凝胶的溶蚀遵循零级动力学方程,释放量随溶蚀量增加而增加,二者间存在线性关系。结论:DSP温度敏感原位凝胶的缓释效果良好,凝胶溶蚀速率、凝胶与释放介质的接触面积是控制药物释放的主要因素。     

星点设计-效应面法对左氧氟沙星泊洛沙姆407/188眼用凝胶的制备工艺优化

目的 应用星点设计-效应面法研制左氧氟沙星温度敏感型眼用凝胶,优化处方工艺,以期获得可用于白内障术后感染的眼用制剂。方法 选择泊洛沙姆407(P407)和泊洛沙姆188(P188)作为凝胶温敏材料,以凝胶温度为响应值,通过星点设计-效应面法进行模型拟合;采用无膜溶出模型考察药物的体外溶蚀行为与释放度。结果 模型拟合获得优化处方：P407浓度25.23%、P188浓度1.89%,胶凝温度的实测值与预测值相对偏差<5%。泪液溶蚀是影响药物释放的主要因素。结论 星点设计-效应面法得到的左氧氟沙星眼用温敏型凝胶处方精密度较高,可作进一步推广应用研究。     

温敏型原位凝胶的热力学及流变学性质研究

目的:以磷酸川芎嗪为模型药物,探讨运用泊洛沙姆P407(P407)制备鼻用温敏型原位凝胶的可行性。方法:采用搅拌转子法测定不同处方磷酸川芎嗪原位凝胶的胶凝温度(胶凝温度:T);在不同温度下,以旋转式黏度计测定加入不同浓度辅料后P407溶液的黏度,以考察黏度随温度的变化规律。结果:P407溶液浓度越高,T越低;辅料的加入可以使P407溶液T升高,而处方药物和等渗调节剂(0.9%NaCl)使P407溶液T降低。当温度升高时,P407黏度增大,而辅料的加入会使P407黏度突变点的温度升高,黏度变小。结论:通过调节P407溶液的浓度或加入一定量辅料的方法,可以使TMPP原位凝胶在鼻腔温度(33℃左右)下胶凝,从而达到增大生物利用度和减少给药流失的要求。     

对乙酰氨基酚鼻用温敏凝胶的制备及其体外释药机制研究

目的：制备对乙酰氨基酚鼻用温敏凝胶,并对其体外释药机制进行研究。方法：以单用15%、16%、18%、20%、25%泊洛沙姆407（P407）,及5%、10%P407与1%、1.5%、2%、2.5%、3%、4%聚乙烯醇（PVA）混合为凝胶基质制备对乙酰氨基酚鼻用温敏凝胶,根据胶凝温度筛选P407和PVA的最佳处方浓度,考察该凝胶的体外累积溶蚀量和体外释药行为并进行释放模型零级动力学、一级动力学、Higuchi方程、Riguchi-Peppas方程拟合。结果：单独使用P407作为凝胶基质,最佳处方浓度为16%～20%,凝胶的溶蚀和体外释药行为均符合零级动力学方程特征;选择混合基质,最佳处方浓度P407为10%,PVA为3%、4%,凝胶的溶蚀符合零级动力学方程特征,而体外释药遵从Higuchi方程,为骨架扩散释放机制。结论：PVA可显著降低P407的用量。单独使用P407作为凝胶基质,药物体外释药受凝胶溶蚀控制;而对于混合基质凝胶,溶蚀对体外释药并非决定性影响因素。     

注射用粉防己碱温敏型缓释原位凝胶的制备

目的 制备以泊洛沙姆407(P407)为基本材料的注射用粉防己碱温敏型缓释原位凝胶,并考察其体外溶出行为.方法 采用冷溶法制备凝胶,以胶凝温度为指标,考察单独使用P407和加入其他辅料F188、PEG1500、HPMC、MC对胶凝温度的影响;采用无膜溶出法考察凝胶的体外溶蚀和释放行为,并采用HPLC测定溶出液中药物的含量,筛选较优处方.结果 胶凝温度随P407浓度的增大而降低;且当P407浓度低于15％时不发生相转变,辅料F188、PEG1500、MC的加入不能制备出符合要求的凝胶;8.0％、8.5％ 、9.0％ HPMC分别与8.0％ P407 混昆合制备凝胶的胶凝温度符合要求;HPMC浓度越高,药物释放越快,8.0％ HPMC和8.0％ P407混合后,胶凝温度和缓释效果均符合实验要求.结论 筛选出的处方中大大降低了P407的浓度,同时胶凝温度和缓释效果均符合实验要求,该温敏性凝胶具有良好的温度敏感性,制备方法简单可行.     

硫酸阿托品眼用温敏凝胶的制备及体外释放研究

摘 要 目的：制备硫酸阿托品眼用温敏凝胶并考察其体外药物释放行为。方法: 以泊洛沙姆407（P407）和泊洛沙姆188（P188）的用量为考察因素,模拟泪液稀释前后的胶凝温度为考察指标,采用星点设计 效应面法优化处方并进行验证;采用无膜溶出模型考察凝胶的体外溶蚀与药物释放行为。结果: 以处方中含有P407 23%、P188 5%为最佳处方,效应面法优化处方的预测值和实测值偏差均小于5%;凝胶溶蚀速率决定药物释放速率,且两者均符合零级动力学方程。结论: 星点设计 效应面法可用于硫酸阿托品眼用温敏凝胶的处方优化,所建立的模型预测性良好;最优处方的制剂体外释放缓慢,符合设计要求。     

眼用司帕沙星阳离子脂质体原位凝胶的研制

目的:研制司帕沙星(SF)眼用阳离子脂质体-原位凝胶(ISG)。方法:采用pH梯度法制备SF脂质体(SFL),用季胺化程度为60%的N-三甲基壳聚糖(TMC60)包衣,用正交试验筛选其最佳处方及工艺,再与泊洛沙姆P407为基质的温度敏感材料混合,制备TMC60包衣的SFL-ISG,并对其形态、粒径、Zeta电位、凝胶溶蚀及释药等体外性质进行考察。结果:本品形态圆整,粒径分布均匀,TMC60包衣后Zeta电位由负转正,药物释放和凝胶溶蚀均呈现良好的零级释放特征。结论:本品结合阳离子脂质体与原位凝胶技术成功制备了TMC60包衣的SFL-ISG,为其体内研究奠定了实验基础。     

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.     

眼用盐酸倍他洛尔脂质体-原位凝胶的研制及体外释药的研究

目的制备盐酸倍他洛尔(BH)眼用脂质体-原位凝胶(ISG),并对其体外释药特性进行考察。方法采用逆向蒸发法制备BH脂质体(BHL);以泊洛沙姆407和188(P407,P188)为温敏性ISG基质,以胶凝温度为指标,筛选P407与P188的最佳配比;采用无膜溶出模型对BHL的体外释放行为进行考察。结果 BHL的平均包封率为(88.24±5.46)%(n=3);当P407与P188的处方用量分别为21%及6%时,胶凝温度最接近人眼表温度(34℃);BHL-ISG体外药物释放和凝胶溶蚀均呈现零级释放特征,两者相关性良好。结论 BHL-ISG结合脂质体和原位凝胶的特点,延缓药物释放,为其角膜滞留性研究奠定了基础。     

Thermosensitive and mucoadhesive in situ gel based on poloxamer as new carrier for rectal administration of nimesulide

Poloxamer 407 has excellent thermo-sensitive gelling properties. Nevertheless, these gels possess inadequate poor bioadhesiveness and high permeability to water, which limited its' application as a thermoresponsive matrix. The main aim of the present investigation was to develop thermosensitive and mucoadhesive rectal in situ gel of nimesulide (NM) by using mucoadhesive polymers such as sodium alginate (Alg-Na) and HPMC. These gels were prepared by addition of mucoadhesive polymers (0.5%) to the formulations of thermosensitive gelling solution containing poloxamer 407 (18%) and nimesulide (2.0%). Polyethylene glycol (PEG) was used to modify gelation temperature and drug release properties. The gelation temperature and drug release rate of the prepared in situ gels were evaluated. Gelation temperature was significantly increased with incorporation of nimesulide (2.0%) in the poloxamer solution, while the addition of the mucoadhesive polymers played a reverse role on gelation temperature. The addition of PEG polymers increased the gelation temperature and the drug release rate. Among the formulations examined, the poloxamer 407/nimesulide/sodium alginate/PEG 4000 (18/2.0/0.5/1.2%) exhibited the appropriate gelation temperature, acceptable drug release rate and rectal retention at the administration site. Furthermore, the micrographic results showed that in situ gel, given at the dose of 20mg/kg, was safe for no mucosa irritation. In addition, it resulted in significantly higher initial serum concentrations, C(max) and AUC of NM compared to the solid suppository.     

无膜释放模型考察直肠用温敏型原位凝胶的体外释放情况

目的:研究直肠用温敏型原位凝胶的体外释药考察方法。方法:采用无膜释放模型,以对乙酰氨基酚为模型药物、泊洛沙姆407为基质制备凝胶;分别采用《中国药典》桨法和常见的水浴振荡法,考察桨法转速(50、75、100r·min-1)、振荡器振荡频率(50、100、150r·min-1)对凝胶中药物释放行为的影响,并对释药数据采用不同的方程进行拟合。结果:桨法释药速率随桨速的增加而加快,但不同桨速间释药行为存在一定差异;振荡法释药速率也随振荡频率的增加而加快,但释药行为基本相似。各释药行为均符合零级方程,并以桨法75r·min-1和振荡法100r·min-1最符合。结论:本文建立的无膜释放模型可用于以泊洛沙姆407为基质的温敏型原位凝胶的释药研究,且桨法宜采用转速为75r·min-1,振荡法宜选用振荡频率为100r·min-1。     

硝酸毛果芸香碱温敏凝胶的研制及溶蚀性能研究

目的制备硝酸毛果芸香碱温敏凝胶,考察其载药凝胶溶蚀行为。方法以泊洛沙姆为温敏凝胶基质制备硝酸毛果芸香碱眼用凝胶,通过凝胶相变温度筛选最佳处方,采用无膜溶蚀实验研究凝胶释药特性。结果18%、19%、20%的泊洛沙姆407溶液在体温范围内发生相变形成凝胶,其pH≈7,凝胶中硝酸毛果芸香碱释放速度分别为0.462、0.393、0.294 mg.min-1。结论18%-20%泊洛沙姆407溶液适合作为眼部给药的温敏凝胶基质,凝胶中药物释放基本符合零级释放行为。     

Release of flurbiprofen from poloxamer 407 gel

Release rates of flurbiprofen from transdemal gels made of poloxamer 407 were evaluated using a membraneless diffusion cell in order to study the effects of formulation variables on flurbiprofen release such as poloxamer 407 (17.5–25%), drug (0.1–1.0%), ethanol (10–20%), PG or PEG 300 (5–15%) concentrations and gel pH (3–7). Isopropyl myristate was employed as a receptor medium for the drug released from the gel. The diffusion coefficient of flurbiprofen decreased linearly as the amount of poloxamer 407 and the drug in the gel increased. The release rate of flurbiprofen was gel pH-dependent and the diffusion coefficient of the drug in the gel increased as the pH of the gel increased. The addition of more ethanol in the gel increased the drug release, resulting from the increase of the thermodynamic activity of the drug in the aqueous phase of the gel. However, the concentration effects of PG and PEG 300 on the release rate of flurbiprofen were negligible over the concentration range used.     

Effect of sodium chloride on the release,absorption and safety of diclofenac sodium delivered by poloxamer gel

Poloxamer solutions prepared with poloxamers and sodium chloride were previously reported to undergo a phase transition to bioadhesive gels at body temperature. For the development of a thermosensitive diclofenac sodium-loaded poloxamer gel, here we investigated the effect of sodium chloride on the release, safety and rectal absorption in rats of diclofenac sodium delivered by the poloxamer gels. P 188 delayed the release rates of diclofenac sodium from poloxamer gels. However, sodium chloride showed no significant effect on the release rates of diclofenac sodium from poloxamer gels. Release mechanism analysis showed the release of diclofenac sodium was proportional to the time. The initial plasma concentrations of diclofenac sodium in the rectal formulation [diclofenac sodium/poloxamer 407 (P 407)/poloxamer 188 (P 188)/sodium chloride (2.5/15/17/0.8%)] were significantly higher compared with those in semi-solid suppository. Furthermore, it gave significantly faster Tmax of diclofenac sodium than did semi-solid suppository, indicating that the diclofenac sodium from poloxamer gel could be absorbed faster than that from semi-solid one in rats. It did not cause any morphological damage to the rectal tissues. These results suggested that poloxamer gel with sodium chloride could be a more effective and safe rectal delivery system of diclofenac sodium.     

安乃近原位凝胶的制备及体外评价

目的 制备安乃近原位凝胶,延长安乃近在体内的作用时间.方法 以泊洛沙姆407(P407)和泊洛沙姆188(P188)作为载体材料,采用冷溶法制备安乃近原位凝胶,考察P407和P188的含量、亚硫酸氢钠及安乃近浓度对胶凝温度的影响,并用透析袋法考察凝胶的体外释药情况.结果 当P407浓度为23％、P188浓度为6％、亚硫酸氢钠的浓度为0.2％时,所制得的安乃近原位凝胶注射剂的胶凝温度合适,为35.3℃时,该凝胶在1h内的平均体外累积释放率为40.57％,较安乃近水溶液同时间内的累积释放率低50.39％.结论 安乃近原位凝胶的温敏性明显,其胶凝温度适合体内给药;安乃近原位凝胶对安乃近药物的释放显示出了明显的缓释效应,可以进一步用于临床.     

Enhanced permeation of triamcinolone acetonide through the buccal mucosa.

To develop new formulations that have suitable bioadhesive force and provide sustained release in buccal area for an extended period of time, bioadhesive gels containing triamcinolone acetonide were prepared using two polymers, carbopol 934 and poloxamer 407 which were selected for their bioadhesiveness and gelling property, respectively. The drug release profiles from the gels were studied as a function of drug concentration and temperature. Different enhancers such as bile salts, glycols and non-ionic surfactants were used for the enhancement of its permeation through buccal mucosa. Among the enhancers used, sodium deoxycholate showed the best enhancing effects.     

丙烯酸-泊洛沙姆407共聚物的合成及其原位胶凝性质

目的制备丙烯酸和泊洛沙姆407构成的共聚物,研究其温度敏感的原位胶凝性质。方法将泊洛沙姆407溶于丙烯酸单体,引发聚合反应,产物用红外光谱和凝胶渗透色谱表征。用旋转黏度计测定共聚物水溶液的黏度随温度的变化。以维生素B12为模型药物,研究药物的释放性质。结果较低浓度的丙烯酸泊洛沙姆407共聚物水溶液具有受热原位胶凝的性质,其胶凝特征与共聚物的组成、浓度、溶液pH等有关,共聚物凝胶可延缓药物释放。结论丙烯酸泊洛沙姆407共聚物可望应用于黏膜给药的原位凝胶递药系统。     

Development and characterisation of modified poloxamer 407 thermoresponsive depot systems containing cubosomes

The purpose of this study is to develop a thermoresponsive sustained release delivery system combining phytantriol cubosomes and poloxamer 407 (P407). P407 undergoes thermoreversible gelation, where it exists as a free-flowing liquid at low temperature and gels upon heating. However, this polymer has the major draw back of fast erosion in aqueous environments which needs to be addressed. Three different concentrations of P407 (12%, 15% and 17% (w/v)) were formulated with various additives (methyl cellulose (MC), dextran, carrageenan and Pluronic-R (25R4)). The rheological characteristics and in vitro stability were investigated. The sol-gel transition temperature of P407 was lowered in the presence of the phytantriol cubosomes. The addition of MC and dextran did not affect the sol-gel transition temperature whereas 25R4 increased the gelation temperature. No transition was observed for the carrageenan formulations. The presence of 25R4 allowed the development of formulations that were free flowing liquid at working temperature (22 °C), gelled at body temperature (37 °C) and had improved stability in an aqueous environment. Both rheological and in vitro stability studies suggested that cubosome-loaded 17% (w/v) P407 with 25R4 in 1:1 molar ratio may have a potential as sustained release delivery system.