共查询到20条相似文献,搜索用时 171 毫秒
1.
目的对氮酮、冰片、薄荷醇促透作用进行比较,为找到更合理有效促透剂提供理论依据。方法在离体透皮实验装置上进行透皮吸收实验和贮库效应的研究。结果氮酮、冰片、薄荷醇单独应用时对甲硝唑经皮渗透均有促进作用,增渗倍数分别为2.48,2.19和2.66;当氮酮与冰片或薄荷醇合用时,促透效应比单用氮酮时显著增强(P〈0.01)。氮酮单独应用时对甲硝唑经皮渗透和贮库效应影响不明显,但氮酮和薄荷醇合用时贮库效应显著增加。结论冰片、薄荷醇均对甲硝唑的皮肤吸收有促透作用,与氮酮合用时效果明显增强。 相似文献
2.
选用立式透皮扩散试验仪,以离体小鼠皮为透皮屏障进行体外透皮实验,研究了促渗剂氮酮、薄荷脑和冰片对当归水溶性成分阿魏酸的体外透皮性能影响,并优选出了较佳复合促渗剂。实验结果表明,三种促渗剂单用时,对阿魏酸透皮性能的影响大小顺序为:薄荷脑>冰片>氮酮,而联合使用时,顺序为:冰片>薄荷脑>氮酮。且优选出的较佳复合促渗剂为2%冰片+2%薄荷脑,结果显示二者联合使用优于氮酮、冰片、薄荷脑单独使用,其24 h单位面积累积透过量(Q24)可达34.32μg/cm2,增渗倍数(ER)可达64.195,分别为单用薄荷脑和冰片的8倍和25倍,且滞后时间在2 h以内,协同作用明显,即优选出的复合促渗剂对当归水溶性成分阿魏酸的促渗效果很好,可为当归及以当归为主药方剂的经皮给药制剂开发提供促渗剂。 相似文献
3.
4.
研究人参皂苷Rg3体外经皮渗透特性以及不同促渗剂的影响。测定人参皂苷Rg3与经皮渗透相关的物理参数。通过扩散池试验,采用HPLC法测定人参皂苷Rg3的累积透过量(Q),拟合Q-t曲线,考察体外经皮渗透性能;测定β-环糊精、吐温-80、油酸、氮酮、薄荷油的增渗倍数(ER),考察不同促渗剂对人参皂苷Rg3经皮渗透性质的影响。人参皂苷Rg3的表观溶解度为66.70μg/mL,油水分配系数(logP)为2.63,熔点为312.2℃。人参皂苷Rg3经皮渗透为恒速过程;不同促渗剂对人参皂苷Rg3的促渗作用存在差异,薄荷油增渗倍数为2.38。人参皂苷Rg3体外释放符合零级过程,薄荷油对其促渗作用效果显著,可作为一种具有发展潜力的新型外用镇痛化合物。 相似文献
5.
6.
通过原位聚合法制备得到ATO/含氟聚丙烯酸酯(PA-F)复合乳液,其中纳米级ATO加入量分别为PA-F树脂质量的0、2%、4%、6%、8%、10%,考察了ATO用量对复合乳液平均粒径及乳液胶膜的光学性能及其他常规性能的影响。结果表明:随着ATO用量的增加,乳液的粒径趋于增大,但体系足够稳定;胶膜的可见光部分的平均透过率并没有太大的影响,平均透过率均高于80%,而近红外部分的平均透过率却急剧下降。当ATO含量为10%时,红外波段的平均透过率仅为39.95%,比纯PA-F胶膜下降了54%,而可见光透过率为81.43%,降幅只有4%。 相似文献
7.
摘 要:为了从硫酸铝中除铁,提出了利用乙醇水溶液对含铁硫酸铝进行除铁的工艺方法。研究了乙醇水溶液的pH、温度、振荡时间对除铁率的影响以及乙醇回收并循环使用的工艺方法。通过实验确定了最佳的工艺参数:乙醇水溶液的pH≤1,温度为25 ℃,振荡时间为2.5 h。经4级逆流除铁,硫酸铝的含铁质量分数可由0.98%降至0.005%以下。负载在乙醇水溶液中的铁经双氧水氧化、氨水沉淀、过滤并蒸馏至干后,乙醇回收率可达99.5%以上。本工艺具有操作简单、无污染、成本低等优点。 相似文献
8.
《应用化工》2022,(1):186-189
为给黄藤素透皮给药选择合适的挥发油促渗剂,以高效液相色谱法测定黄藤素的含量,采用立式扩散池法研究桉叶油、艾叶油、当归油、连翘油对黄藤素透皮给药的影响;实验结束后,用DSC扫描观察皮肤的特征峰变化。结果表明,5 h时,艾叶油组药物的累积透过量分别是被动扩散组、桉叶油组、当归油组、连翘油组的1.82,1.16,1.48,1.63倍,药物的累积渗透量随着艾叶油浓度的增加而增加,艾叶油浓度1.5%时,其促渗能力最强。DSC图谱表明,不同挥发油对皮肤的特征峰具有不同的影响,促渗能力较好的挥发油使皮肤的特征峰消失;当艾叶油的浓度由0.5%增加到1.5%,DSC图谱发生相应变化,浓度为1.5%和2.0%时具有相似的图谱,而浓度为2.5%时的DSC图谱与0.5%的图谱相似。艾叶油能够显著促进黄藤素的透皮给药,且最佳的浓度为1.5%,其机理可能是通过扰乱或破坏皮肤角质层的有序结构来增强皮肤对药物的渗透性,因此,艾叶油可作为黄藤素透皮给药的理想促渗剂而具有广泛的应用前景。 相似文献
9.
《应用化工》2016,(1):186-189
为给黄藤素透皮给药选择合适的挥发油促渗剂,以高效液相色谱法测定黄藤素的含量,采用立式扩散池法研究桉叶油、艾叶油、当归油、连翘油对黄藤素透皮给药的影响;实验结束后,用DSC扫描观察皮肤的特征峰变化。结果表明,5 h时,艾叶油组药物的累积透过量分别是被动扩散组、桉叶油组、当归油组、连翘油组的1.82,1.16,1.48,1.63倍,药物的累积渗透量随着艾叶油浓度的增加而增加,艾叶油浓度1.5%时,其促渗能力最强。DSC图谱表明,不同挥发油对皮肤的特征峰具有不同的影响,促渗能力较好的挥发油使皮肤的特征峰消失;当艾叶油的浓度由0.5%增加到1.5%,DSC图谱发生相应变化,浓度为1.5%和2.0%时具有相似的图谱,而浓度为2.5%时的DSC图谱与0.5%的图谱相似。艾叶油能够显著促进黄藤素的透皮给药,且最佳的浓度为1.5%,其机理可能是通过扰乱或破坏皮肤角质层的有序结构来增强皮肤对药物的渗透性,因此,艾叶油可作为黄藤素透皮给药的理想促渗剂而具有广泛的应用前景。 相似文献
10.
11.
12.
A series of poly(acrylic acid) (PAA)–poly(vinyl alcoho) (PVA) semiinterpenetrating (SIPN) and interpenetrating (IPN) polymer network membranes were prepared by crosslinking PVA alone or by crosslinking both PVA and PAA. Glutaraldeyde and ethylene glycol were used as crosslinking agents for the PVA and PAA networks, respectively. The presence of PAA increases the permeability of the membranes while the presence of PVA improves their mechanical and film-forming properties. The mechanical properties of the membranes were investigated via tensile testing. These hydrophilic membranes are permselective to water from ethanol–water mixture and to ethanol from ethanol–benzene mixtures. The IPN membranes were employed for the former mixtures and the SPIN membranes for the latter, because the IPN ones provided too low permeation rates. The permeation rates and seperation factors were determined as functions of the IPN or SIPN composition, feed composition, and temperature. For the azeotropic ethanol–water mixture (95 wt % ethanol), the separation factor and permeation rate at 50°C of the PAA-PVA IPN membrane, containing 50 wt % PAA, were 50 and 260 g/m2h, respectively. For the ethanol–benzene mixture, the PAA–PVA SIPN membranes had separation factors between 1.4 and 1200 and permeation rates between 6 and 550 g/m2h, respectively, depending on the feed composition and temperature. © 1996 John Wiley & Sons, Inc. 相似文献
13.
Habib I. Shaban 《应用聚合物科学杂志》1998,70(12):2361-2369
The importance of boundary layer was investigated for the hydrolysis of ethyl acetate using a dense standard poly(vinyl alcohol) (PVA) membrane. A resistance in a series model approach was used to study the effect of a boundary layer for the permeation of aqueous organic mixtures involved in the study. The initial feed mixture consisted of 10% water (H2O), 40% ethyl acetate (EA), 50% acetic acid (AA), and 0% ethanol (E) (all weight percentage basis). The experiments were conducted at 65°C. The amount of all species in the feed reservoir was found to decrease with time. Selectivity calculations based on a resistance in the series model approach indicates that the boundary layer contributes to selective permeation of aqueous organic compounds. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 2361–2369, 1998 相似文献
14.
《分离科学与技术》2012,47(12):1599-1617
Abstract Copolymer membranes prepared by bulk copolymerization of polyethylene glycol dimethacrylates of three different degrees of polymerization as macromonomer and benzyl methacrylate as comonomer were used for the separation of aqueous ethanol solutions in both pervaporation and evapomeation. The copolymer membranes preferentially permeated water from an aqueous ethanol solution in evapomeation. In pervaporation, ethanol was predominantly permeated from an aqueous ethanol solution through the copolymer membranes containing a long polyethylene glycol (PEG) chain above about 20 wt% PEG content in a copolymer. This result was attributed to a remarkable swelling of the copolymer membrane containing a long PEG chain by the aqueous ethanol solution in pervaporation. In evapomeation, both the separation factors and the permeation rates through these membranes are not much affected by the ethanol concentration in the feed vapor. In pervaporation, they were significantly dependent on the ethanol concentration in the feed solution. The above results are discussed from the viewpoint of the physical structure of the membrane in evapomeation and pervaporation. 相似文献
15.
《分离科学与技术》2012,47(10):893-904
Abstract Ethanol-water solutions may be concentrated by pervaporation through silicone rubber and regenerated cellulose film. Using silicone, separation factors (SF) decrease as the ethanol concentration in the feed solution increases (SF = 6.5 using 12.9 w/w% ethanol and 1.4 using 83.2% ethanol at 30°C). The temperature effect on separation factors is negligible, but is appreciable on permeation rates. Ethanol permeation rates in the dialysis mode are not linear with ethanol chemical potentials in solution; silicone swelling coefficients also increase noticeably with alcohol concentration in aqueous solutions, indicating that preferential ethanol sorption occurs and is responsible for the separation. 相似文献
16.
Michiaki Matsumoto Takaaki Ohtake Makoto Hirata Tadashi Hano 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1998,73(3):237-242
The extraction rates of amino acids from alkaline aqueous solution into an emulsion liquid membrane containing tri-n-octylmethylammonium chloride as a carrier and Paranox 100 as an emulsifier were measured using a stirred transfer cell. The effects of agitation speed (0·33–0·66 rev s−1), amino acid concentrations (0·5–50 mol m−3) and temperature (10–45°C) on the extraction rates were examined. The results were analyzed by a double-film model. The mass transfer coefficients of amino acids (0·26–1·58×10−5 m s−1) and their complexes (0·60–1·72×10−5 m s−1) were found to correlate well with the hydrophobicities of the amino acids. It was found that the surfactant layer influenced the mass transfer processes of both amino acids in the aqueous film and their complexes in the organic film. The permeation of amino acids with a large hydrophobicity through the emulsion liquid membrane was promoted by both high distribution and larger mass transfer rates. © 1998 Society of Chemical Industry 相似文献
17.
该文介绍了乳状液膜法分离富集废旧镍镉电池中的镉离子。乳状液膜主要由溶剂(煤油)、表面活性剂(Span80)、载体〔二(2-乙基己基)膦酸,P204〕和内水相氨水组成。对影响镉离子渗透和分离过程的重要变量进行了考察,分析了乳状液膜的载体体积分数、外水相pH、搅拌时间、乳水比(乳液与外水相体积比)及Span80体积分数对镍镉分离效果的影响,从而选择出最佳的分离条件为:φ(P204)=4.4%,φ(Span80)=8.8%,pH=5.5,乳水比0.5,搅拌时间10min。用此乳状液膜进行100L反应釜的工业放大实验,镉的迁移率可达93.3%,而镍的迁移率仅为14.6%。 相似文献
18.
The characteristics of permeation and separation for aqueous solutions of methanol and ethanol through a poly[bis(2,2,2-trifluoroethoxy)phosphazene] (PBTFP) membrane were studied by pervaporation and evapomeation. In pervaporation technique, methanol was preferentially permeated in all of the feed solution compositions and ethanol was permeated in lower ethanol concentrations of the feed solution. Water was predominantly permeated from the feed solutions with higher ethanol concentration. In evapomeation technique, water was selectively permeated in both all of the feed vapor compositions for aqueous methanol and ethanol solutions. These different permselectivities depended on the feed composition and the membrane permeation technique and could be discussed by a difference in the mechanisms of permeation and separation. It was found that the permeation rate was influenced remarkably by the degree of swelling of the PBTFP membrane and the permselectivity for water of aqueous alcoholic solutions was enhanced by an increasing degree of swelling of the membrane. When the degree of swelling of the membrane with rising permeation temperature was small, both the permeation rate and permselectivity for alcohol in pervaporation and evapomeation increased with the permeation temperature. The above results are discussed considering the PBTFP membrane structure in evapomeation and pervaporation. 相似文献
19.
Iqbal Ahmed Nasrul Fikry Che Pa Mohd Ghazali Mohd Nawawi Wan Aizan Wan Abd Rahman 《应用聚合物科学杂志》2011,122(4):2666-2679
In this article a modified polydimethylsiloxane (PDMS) blended polystyrene (PS) interpenetrating polymer network (IPN) membranes supported by Teflon (polytetrafluoroethylene) ultrafiltration membrane were prepared for the separation of ethanol in water by pervaporation application. The relationship between the surface characteristics of the surface‐modified PDMS membranes and their permselectivity for aqueous ethanol solutions by pervaporation are discussed. The IPN supported membranes were prepared by sequential IPN technique. The IPN supported membrane were tested for the separation performance on 10 wt % ethanol in water and were characterized by evaluating their mechanical properties, swelling behavior, density, and degree of crosslinking. The results indicated that separation performance, mechanical properties, density, and the percentage of swelling of IPN membranes were influenced by degree of crosslink density. Depending on the feed temperature, the supported membranes had separation factors between 2.03 and 6.00 and permeation rates between 81.66 and 144.03 g m?2 h?1. For the azeotropic water–ethanol mixture (10 wt % ethanol), the supported membrane had at 30°C a separation factor of 6.00 and a permeation rate of 85 g m?2 h?1. Compared to the PDMS supported membranes, the PDMS/PS IPN supported blend membrane ones had a higher selectivity but a somewhat lower permeability. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
20.
The purpose of this paper is to investigate the swelling of emulsion liquid membranes using dithio-DEHPA as carrier. The application of interest was the removal of zinc from a synthetic aqueous solution which simulates a zinc plant effluent. The effect of several variables such as the concentration of carrier in the membrane, stirring speed and permeation time on the swelling of the emulsion is reported. Experimental results show that occlusion depends mainly on the amount of carrier in the membrane and can be significant when the concentration of carrier is lower than 6.0%. The interfacial tension analysis confirms that the size of globules is influenced by the concentration of carrier in the membrane. Stirring speed and permeation time are related to the water transport and must be kept at low values. 相似文献