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1.
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。  相似文献   

2.
壳聚糖对温敏性原位凝胶基质体外流变学特性的影响   总被引:7,自引:1,他引:7  
目的考察壳聚糖对泊洛沙姆为基质的温敏性原位凝胶流变学特性的影响,为两者的配伍使用提供依据。方法将不同质量分数的壳聚糖与泊洛沙姆溶液(P407和P188的质量分数均为15%)制备成原位凝胶,测定原位凝胶的体外胶凝温度、胶凝强度和生物黏附力。结果当壳聚糖的质量分数从0上升至0.6%时,基质的胶凝强度和生物黏附力均逐渐升高,胶凝温度无明显变化。结论壳聚糖可改善以泊洛沙姆为基质的原位凝胶的流变学性质。  相似文献   

3.
尼非韦罗阴道温敏原位凝胶的流变学研究   总被引:2,自引:0,他引:2  
目的:应用动态流变实验测定温度敏感型原位凝胶的流变性质,以预测其在体胶凝(相变)行为。方法:通过处方筛选,确定以泊洛沙姆407和188作为基质,制备尼非韦罗阴道温敏原位凝胶(NFVR-TISG)。通过差示扫描热量法(DSC)测定NFVR-TISG胶凝温度。采用动态流变学实验测定NFVR-TISG在不同温度下相变过程中的流变参数,及NFVR-TISG经模拟阴道夜稀释(5∶1)后的流变参数。结果:NFVR-TISG在室温条件下为黏弹性较低的牛顿流体,温度升至29℃时形成凝胶状态;相变行为表现为黏弹性呈指数增长,相角降低;流变学结果显示的胶凝温度与DSC结果(30.4℃)基本一致;模拟阴道液稀释后NFVR-TISG约在35℃发生相转变。结论:体外流变学特点显示NFVR-TISG符合临床阴道局部用药物要求。用于体外评价的动态流变学实验可反映温敏凝胶的黏弹性流体力学特点。  相似文献   

4.
丙烯酸-泊洛沙姆407共聚物的合成及其原位胶凝性质   总被引:1,自引:0,他引:1  
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。  相似文献   

5.
氯霉素温敏型眼用原位凝胶的研制   总被引:1,自引:0,他引:1  
目的制备氯霉素泊洛沙姆眼用原位温敏型凝胶并建立其质量控制方法。方法以泊洛沙姆P407和P188为温敏材料,通过测定溶液-凝胶相转变温度优化处方;采用紫外分光光度法测定氯霉素含量。结果氯霉素温敏型原位凝胶的胶凝温度随P407浓度增大而降低,随P188浓度增加先升高后降低,模拟泪液的稀释可使胶凝温度升高,建立了泪液稀释后相变温度与泊洛沙姆浓度的拟合方程,经Design-Expert软件优化出的氯霉素温敏型原位凝胶最佳处方为25%P407和4.19%P188;优化处方在29.5℃时为自由流动的液体,泪液稀释后在34.6℃能够发生相变形成凝胶。结论该眼用温敏凝胶符合眼部应用要求,体现出良好的应用前景。  相似文献   

6.
目的:合成了新型温敏/pH敏感型高分子材料异丙基丙烯酰氨-g-瓜耳胶(PNIAAr-g-GG),并对其性质进行研究.方法:采用链引发法制备了异丙基丙烯酰氨-g-瓜耳胶共聚物,以戊二醛为交联剂制备了聚合物凝胶及其温敏游离膜,并用红外光谱与热重分析对聚合物结构进行确证;采用黏度法测定了聚合物的低温溶解温度(lower critical solution temperature,LCST);考察了离子强度对聚合物LCST的影响,温度对温敏膜药物透过性的影响,同时考察了温度、离子强度及pH值对聚合物凝胶释药的影响.结果:聚合物的LCST为37.5℃,且随溶液中离子强度的增高而线性降低;当温度高于聚合物LCST时,凝胶中药物释放速率减慢,药物经膜的透过性增加;凝胶释药速率随溶出介质中离子强度的增高而降低,随介质pH值降低而加快.结论:异丙基丙烯酰氨-g-瓜耳胶凝胶骨架片具有明显的温度敏感性及pH敏感性.  相似文献   

7.
目的 制备喷昔洛韦(penciclovir,PCV)温度敏感原位凝胶,对其进行了处方优化筛选,并建立其质量控制方法.方法 考察含有不同泊洛沙姆407(Pluronic F127)和泊洛沙姆188(Pluronic F68)浓度配比的处方对原位凝胶胶凝温度、流变学性质、质构特性和体外药物释放行为等的影响,从而设计和优化处方.结果 得到最佳凝胶基质组成为19%F127/0.3%F68,其胶凝温度33.7℃;达到34℃时粘度和胶凝强度明显增大;PCV自凝胶中的释放具有一定的缓释效果.结论 喷昔洛韦眼用温度敏感原位凝胶有望开发成为一种新型眼部给药制剂.  相似文献   

8.
目的:研制美沙拉嗪羟丙基β-环糊精(HP-β-CD)包合物温敏型液体栓,并对其体外性质进行考察。方法:以泊洛沙姆407和泊洛沙姆188为温敏材料,负载美沙拉嗪HP-β-CD包合物,制备美沙拉嗪HP-β-CD包合物温敏型液体栓;比较美沙拉嗪HP-β-CD包合物温敏型液体栓和美沙拉嗪液体栓的黏度、胶凝强度、生物黏附性、体外凝胶溶蚀及药物释放等。结果:与MSZ液体栓相比,美沙拉嗪HP-β-CD包合物的加入不影响液体栓的胶凝温度,能使液体栓的黏度、胶凝强度及生物粘附性显著增加。凝胶溶蚀不受包合物的影响,而药物释放率得到显著提高,且药物释放与凝胶溶蚀呈现良好的线性关系。结论:美沙拉嗪HP-β-CD包合物温敏型液体栓具有较理想的胶凝温度,以及良好的粘性、胶凝强度及生物粘附性,且体外释药速度较MSZ液体栓快。  相似文献   

9.
泊洛沙姆407水溶液的流变学性质   总被引:1,自引:0,他引:1  
Hu J  Chen DW  Quan DQ 《药学学报》2011,46(2):227-231
本文对泊洛沙姆407(商品名为普朗尼克F127)进行了流变学性质的考察。通过剪切速率触变性实验、温度敏感性实验和多次升温后表观黏度复原性实验得到了泊洛沙姆407各项流变学参数。结果表明,随着泊洛沙姆407水溶液浓度的提高,其由牛顿流体转变为假塑性流体,触变性和胶凝温度均逐渐降低(15.25%泊洛沙姆407可在体温下形成凝胶)。本文为泊洛沙姆407作为凝胶剂基质的应用提供了可参考的流变学数据。  相似文献   

10.
目的 研究壳聚糖季铵盐温敏凝胶及性质.方法 采用试管倾斜法测定胶凝时间,考察壳聚糖季铵盐的浓度、体积比、温度等对胶凝时间的影响,采用吸光度经时变化法测定相变动力学,并用透析法测定载药凝胶的体外释放.结果 56% GPS/2% HTCC体积配比1:5、温度37℃时,胶凝时间为3.53min,钙黄绿素载药凝胶具有良好的缓释...  相似文献   

11.
The effect of physical and chemical variables on consistency of Carbopol 940 and 941 gels was investigated by continuous shear rheometry. Gels provided plastic flow curves with negligible hysteresis. Continuous shear properties were not greatly affected by centrifuging, milling, temperature cycling, and ageing. Initial addition of neutralizing agent (0–6% w/w for 3% gels) markedly increased consistency; further addition caused a more gradual increase. Daylight reduced consistency. Apparent viscosities varied exponentially with concentration. Increased temperature gradually decreased apparent viscosity. Solvents had a variable effect on apparent viscosities which could not be correlated with solvent viscosity nor molecular weight. Apparent viscosities for gels neutralized with different bases were independent of type of base used.Small strain testing investigated fundamental properties of Carbopol gels and determined the effect of polymer concentration, temperature, neutralization, different solvents and neutralizers. Gels were linear viscoelastic and to a first approximation were elastic solids. Creep compliance varied exponentially with concentration and showed no correlation with solvent or neutralizer type.  相似文献   

12.
Thermal rheological studies describe the flow properties of A37 agarose sols. Their behavior displays plastic flow as shear strain increases. Rheological characteristtcs, viscosity, apparent viscosity and yield value are measured. Their variations with decreasing temperature pathway followed structural changes within the gelling process. A thixotropic flow occurred at the sol-gel transition point. The concentration of polymer in the gel is related to the absolute temperature of gelification in order to evaluate the heat of crosslinking. The high value corroborates the assumption of the crystalline nature of agarose gels.  相似文献   

13.
The effect of nicotinamide on the properties of aqueous hydroxypropylmethylcellulose (HPMC) solutions was studied. Rheological studies showed that solutions of HPMC of concentration less than 3.0 w/v.% did not form gels and exhibited Newtonian flow patterns at 25 degrees C. The inclusion of nicotinamide increased the viscosity of HPMC solutions, which indicates that nicotinamide expanded the HPMC coils in aqueous solution. When the temperature of the solutions was raised, they formed gels that were detected by viscometry and oscillation tests as abrupt increases in viscosity, storage modulus and loss modulus and an abrupt decrease in loss angle. Nicotinamide exhibited a salting in effect on the HPMC solutions resulting in an increase in gelation temperatures and cloud points. These effects are considered to be due to the hydrogen-bonding of nicotinamide to HPMC molecules, which was suggested by a shift to a longer wavelength of the UV spectra of aqueous nicotinamide solutions by the addition of HPMC. These results suggested that nicotinamide has affinity with the hydrophilic groups of HPMC.  相似文献   

14.
Studies on the effect of polymers on physicochemical properties hydrogels for topical use. Rheological parameters were tested and pharmaceutical availability of hydrocortisone from gels. Formulation of hydrogels with 1% hydrocortisone content produced on the basis of methylcellulose, carboxymethlcellulose sodium salt and Carbopol 934 P.  相似文献   

15.
The purpose of this study was to investigate the properties of methylparaben as a solid-state plasticizer for Eudragit RS PO during a hot-melt extrusion process. Extruded matrices containing different levels of methylparaben and Eudragit RS PO, were prepared by feeding the powder blend through a hot melt extruder. The melt viscosity of the polymer blends was assessed by torque rheometry using a Brabender Plasticorder. The physicochemical properties of the extruded methylparaben-containing polymer matrix were characterized by differential scanning calorimetry and X-ray diffraction. Solid state nuclear magnetic resonance spectroscopy (NMR) was used to study the possible interaction between methylparaben and Eudragit RS PO polymer. The results demonstrated that the glass transition temperature of the Eudragit RS PO decreased with increasing levels of methylparaben in the extrudate, due to an increase in the chain mobility of Eudragit RS PO. The crystallinity of methylparaben was absent following hot-melt processing. At increasing levels of methylparaben in the extrudates, a decrease in the melt viscosity was seen due to a plasticization of the polymer. Rheological properties of the extrudates containing methylparaben were compared with the extrudates containing conventional plasticizers. It was found that methylparaben was as effective as triethyl citrate (TEC) in reducing torque during the extrusion process. Solid state NMR spectra indicated a change in the chemical shift of Eudragit RS PO plasticized with methylparaben, which could be ascribed to an interaction between the hydroxyl group of the methylparaben and the ester group of the Eudragit RS PO polymer. The results of this study demonstrated that methylparaben could be used as a solid-state plasticizer for the Eudragit RS PO polymer when a hot melt extrusion technique was employed in the preparation of sustained release tablets.  相似文献   

16.
Rheological properties of two different commercial grades of Microcrystalline Cellulose/Sodiumcarboxymethyl Cellulose (MCC/NaCMC) hydrogels were investigated. A controlled stress rheometer fitted with parallel plate geometry was used. Application of the Cross Model relating the viscosity and shear rate data indicated the gels are extremely shear thinning. The two grades of Avicel (RC-591 and CL-611) made of varying MCC and NaCMC concentrations, exhibited distinguishable changes in yield stress and shear thinning behavior attributable to the individual composition. The hydrogels reached structural equilibrium in 1 week after manufacture. Lot to lot variability of Formula A hydrogels had minimal influence on the rheological properties of the resulting hydrogels. The yield stress and/or initial viscosity values observed were proportional to the concentration or phase volume of the MCC/NaCMC in water.  相似文献   

17.
The purpose of the present study was to investigate lecithin-rice bran oil rheological properties with the view to consider these as potential saliva substitutes in patients with severe xerostomia and salivary hypofunction. Pseudo-ternary phase diagrams of rice bran oil, lecithin and water mixtures were constructed and characterised using polarising light microscopy. Viscoelastic properties, which we hypothesise are important determinants in product performance, were analysed using both flow and oscillatory rheology. Rheological properties were influenced by composition, frequency and shear stress. Frequency-dependent viscoelasticity was observed in some formulations where viscosity dominated (tan δ > 1) at frequencies under 5 Hz and elasticity dominated (tan δ < 1) at higher frequencies. Threshold frequencies were determined for each formulation, where a peak in loss tangent was observed, coinciding with a reduction in the storage modulus and increase in loss modulus. The frequency-dependent behaviour of emulsions are of interest because these combinations exhibit viscous behaviour at low frequencies, which may improve lubrication of the oral cavity at rest, whereas increased elasticity at higher frequencies may improve retention during higher-shear tasks such as swallowing and speaking.  相似文献   

18.
地塞米松磷酸钠温度敏感原位凝胶的特性研究   总被引:2,自引:1,他引:2  
本文以泊罗沙姆PluronicF127为温度敏感原位凝胶材料,考察了PluronicF127与PluronicF68不同浓度处方对地塞米松磷酸钠温度敏感原位凝胶的胶凝温度、相转变温度、凝胶强度、稳态黏度、溶蚀和药物释放行为等特性的影响。采用试管倒转法测定胶凝温度;旋转流变仪测定相转变温度、弹性模量、稳态黏度等流变学参数;无膜溶出法测定凝胶的溶蚀行为;HPLC测定地塞米松磷酸钠的释放度。结果表明,随着处方中F127浓度的增高,凝胶的胶凝温度和相转变温度降低,黏度和弹性模量增加,溶蚀速率和药物释放速率减慢;而处方中F68对凝胶特性的影响与F127相反。温度敏感原位凝胶在低温时为牛顿流体,黏度很小;随着温度升高,黏度增大;当增至相转变温度附近,表现出典型的假塑性流体特征;药物释放速率受控于凝胶溶蚀速率,二者遵循零级动力学方程。处方中含F127 22.5% / F68 2.5%的地塞米松磷酸钠温度敏感原位凝胶的性质与临床治疗要求基本吻合,有望在临床中获得应用。  相似文献   

19.
Abstract

The drug release profile from hydrophilic matrix tablets can be crucially affected by the variability of physicochemical properties of the controlled release agent. This study investigates and seeks to understand the functionality-related characteristics (FRCs) of hydroxypropyl methylcellulose (HPMC) type 2208, K4M grade, that influence the release rate of the model drug carvedilol from hydrophilic matrix tablets during the entire dissolution profile. The following FRCs were examined: particle size distribution, degree of substitution, and viscosity. Eight different HPMC samples were used to create a suitable design space. Multiple linear regression (MLR) and partial least squares regression (PLSR) analyses were used to create models for each time point. The PLSR results show that the first part of the drug release profiles is mainly regulated by the HPMC particle size. Apparent viscosity and hydroxypropoxy content (%HP) become important in later stages of the drug release profile, when the influence of particle size distribution decreases. These findings make it possible to better understand the importance of FRCs. Larger HPMC particles increase drug release in the first part of the drug release profile, whereas decreased apparent viscosity and a higher degree of %HP increase the drug release rate in the later part of the drug release profile.  相似文献   

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