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为了考察药物5-氟尿嘧啶(5-Fu)与吲哚美辛(IDMC)的协同作用, 采用超临界流体强制分散溶液技术(SEDS), 以二氯甲烷/二甲亚砜为共溶剂, 制备了复合5-Fu和IDMC的L-聚乳酸(PLLA)微球。利用单因素法探索了制备复合微球的最佳外部条件, 通过表面形貌、 载药量、 粒径分布、 释放性能的检测和体外细胞实验来表征微球的各项性能。结果表明: 当共溶剂二氯甲烷/二甲亚砜比例为30∶1时, 制备该微球的优化条件为39℃、 14MPa; 微球形貌呈类球形, 粒径分布在0.5~5μm; 复合IDMC后微球具有更优良的缓释效果; 载药微球对A549细胞系增殖有明显的抑制作用, 但与复合IDMC前后微球共培养的2组细胞的相对生长速率(RGR)无显著性差异。 相似文献
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Liu H Zhou LL Wei LL Hong-Guo Nie SF Yang XG Tang R Pan WS 《Drug development and industrial pharmacy》2007,33(9):959-966
The purpose of this study was to investigate the possibility of preparing solid dispersions of the poorly soluble budesonide by supercritical fluid (SCF) technique, using poly (ethylene oxide) (PEO) as a hydrophilic carrier. The budesonide-PEO solid dispersions were prepared, using supercritical carbon dioxide (SC CO2) as the processing medium, and characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), solubility test and dissolution test in order to understand the influence of the SCF process on the physical status of the drug. The endothermic peak of budesonide in the SCF-treated mixtures was significantly reduced, indicating that budesonide was in amorphous form inside the carrier system. This was further confirmed by SEM and PXRD studies. The enhanced dissolution rates of budesonide were observed from SCF-treated budesonide-PEO mixtures. The amorphous characteristic of the budesonide, the better mixing of drug and PEO powders in the presence of SC CO2, together with the improved wettability of the drug in PEO, produced a remarkable enhancement of the in vitro drug dissolution rate. Thus, budesonide-PEO solid dispersions with enhanced dissolution rate can be prepared using organic solvent-free SCF process. 相似文献
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Hui Liu Li-Li Zhou Lan-Lan Wei Hong-Guo Shu-Fang Nie Xing-Gang Yang 《Drug development and industrial pharmacy》2013,39(9):959-966
The purpose of this study was to investigate the possibility of preparing solid dispersions of the poorly soluble budesonide by supercritical fluid (SCF) technique, using poly (ethylene oxide) (PEO) as a hydrophilic carrier. The budesonide-PEO solid dispersions were prepared, using supercritical carbon dioxide (SC CO2) as the processing medium, and characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), solubility test and dissolution test in order to understand the influence of the SCF process on the physical status of the drug. The endothermic peak of budesonide in the SCF-treated mixtures was significantly reduced, indicating that budesonide was in amorphous form inside the carrier system. This was further confirmed by SEM and PXRD studies. The enhanced dissolution rates of budesonide were observed from SCF-treated budesonide-PEO mixtures. The amorphous characteristic of the budesonide, the better mixing of drug and PEO powders in the presence of SC CO2, together with the improved wettability of the drug in PEO, produced a remarkable enhancement of the in vitro drug dissolution rate. Thus, budesonide-PEO solid dispersions with enhanced dissolution rate can be prepared using organic solvent-free SCF process. 相似文献
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Jiraporn Chingunpitak Satit Puttipipatkhachorn Yuichi Tozuka Kunikazu Moribe Keiji Yamamoto 《Drug development and industrial pharmacy》2013,39(6):609-617
The purpose of this study was to prepare fine particles of antimalarial drug dihydroartemisinin (DHA) by rapid expansion of supercritical solutions (RESS) using carbon dioxide as supercritical fluid. The mechanical grinding by jet mill and additional vibration rod mill also was performed as a comparative method. In the RESS process, drug particles were prepared by varying processing conditions, including extraction condition, pre-expansion condition, nozzle diameter, nozzle temperature, and collecting distance. Particle size and morphology and physicochemical characteristics of the drug particles were investigated. The RESS process could produce the smaller drug particles (about 1–2 μm) when compared to mechanical grinding method (about 7 μm). All RESS processing parameters had an effect on size and morphology of drug particles. The particle size of drug was related to the solubility of drug in supercritical CO2 at each processing condition. The fine particles of DHA (about 1 μm) with narrow size distribution could be obtained at extraction pressure of 18 MPa and extraction temperature of 32°C, which was closed to the critical temperature of supercritical CO2 whereas broad size distribution was obtained at extraction temperature of 60°C. Powder X-ray diffraction study indicated that the RESS-processed particles were in crystalline form. The results revealed that RESS process is applicable for micronization of DHA. 相似文献
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超临界流体的应用研究:PET的分解,原料回收 总被引:17,自引:0,他引:17
采用超临界流体技术对PET塑料的分解,原料回收进行了工作总结,证实了超临界流体在塑料分解上的利用,为塑料资源再利用指明了一条新途径。 相似文献
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The effect of adsorption on the measurement of diffusion coefficients by the Taylor dispersion technique is investigated by modifying the governing equation to account for reversible, nonequilibrium adsorption. The resulting two-dimensional equations are solved by an explicit finite-difference technique. Experimental data for the acridine carbon dioxide system indicated that acridine adsorbs on the walls on the tubing and these data were investigated with this model. The influence of carious parameters including the number of sites and the rates of adsorption desorption was investigated by conducting a parametric sensitivity analysis on the model. It was found that adsorption of the solute on the wall of the tubing could produce an error as high as 35% on the measured diffusion coefficient compared to the actual diffusion coellicient. Examination of the influence of each of the parameters will enable Inure investigators to reduce the effect of adsorption in the measurement of diffusion coefficients by Taylor dispersion. 相似文献
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超细微粒,特别是纳米级粒子的研制,在当前的高新技术中己成为一热门领域,在材料、化工、轻工、冶金、电子、生物医学等领域得到广泛应用.超临界流体技术制备超微粉体是一项新技术.本文介绍了近年来开发的一些新方法和新工艺,诸如超临界溶液快速膨胀法,超临界流体抗溶剂法,超临界流体化学反应和超临界干燥法.重点介绍了超临界溶液快速膨胀法、超临界流体抗溶剂法的研究进展及其影响因素.并指出,要将这些技术应用于工业化生产,尚需在理论上有一定的突破. 相似文献
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绿色超临界流体的应用研究 总被引:1,自引:0,他引:1
超临界流体具有与气体相似的密度、粘度、扩散系数等特性 ,应用领域日益广泛 ,主要有 :萃取、催化反应、结晶、吸附、材料制备、环境保护、食品工业、医药工业、染色工业、色谱分析、生物工程等。论述了超临界流体在这些领域的最新研究成果 ,重点介绍超临界流体在环境保护、染色工业、吸附过程、陶瓷脱脂、材料制备过程中的应用 相似文献
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超临界流体干燥理论、技术及应用 总被引:2,自引:0,他引:2
超临界流体干燥法是制备具有很高比表面和孔体积及较低堆密度、折光指数和热导率的块状气凝胶或粉体的重要途径之一。本文详细评述了超临界流体干燥理论和技术的历史背景与研究现状,简要介绍了气凝胶在催化剂、热绝缘材料、高能物理粒子探测器、超细材料、玻璃和陶瓷等诸方面的应用和发展前景。 相似文献
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Thomas J. Bruno 《Journal of research of the National Institute of Standards and Technology》1989,94(2):105-112
A supercritical fluid chromatograph has been designed and constructed to make physicochemical measurements, while retaining the capability to perform chemical analysis. The physicochemical measurements include diffusion coefficients, capacity ratios, partition coefficients, partial molar volumes, virial coefficients, solubilities, and molecular weight distributions of polymers. In this paper, the apparatus will be described in detail, with particular attention given to its unique features and capabilities. The instrument has recently been applied to the measurement of diffusion coefficients of toluene in supercritical carbon dioxide at a temperature of 313 K, and pressures from 133 to 304 bar (13.3–30.4 MPa). The data are discussed and compared with previous measurements on similar systems. 相似文献
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Han-Bing Wang Fei-Fei Yang Xiu-Mei Gai Bing-Chao Cheng Jin-Yu Li Hao Pan 《Drug development and industrial pharmacy》2017,43(9):1460-1471
In this study, furbiprofen/hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complexes were prepared to improve the drug dissolution and facilitate its application in hydrophilic gels. Inclusion complexes were prepared using a supercritical fluid processing and a conventional optimized co-lypholization method was employed as a reference. The entrapment efficacy and drug loading of both methods were investigated. Evaluation of drug dissolution enhancement was conducted in deionized water as well as buffer solutions of different pH. Carbopol 940 gels of both flurbiprofen and flurbiprofen/HPβCD inclusion complexes, with or without penetration enhancers, were prepared and percutaneous permeation studies were performed using rat abdominal skin samples. Formation of flurbiprofen/HPβCD inclusion complexes was confirmed by Fourier transform-infrared spectroscopy, differential scanning calorimetry, X-ray diffraction and scanning electron microscopy. The results obtained showed that SCF processing produced a higher EE (81.91?±?1.54%) and DL (6.96?±?0.17%) compared with OCL with values of 69.11?±?2.23% and 4.00?±?1.01%, respectively. A marked instantaneous release of flurbiprofen/HPβCD inclusion complexes prepared by SCF processing (103.04?±?2.66% cumulative release within 5?min, a 10-fold increase in comparison with flurbiprofen alone) was observed. In addition, this improvement in dissolution was shown to be pH-independent (the percentage cumulative release at pH 1.2, 4.5, 6.8 and 7.4 at 5?min was 95.19?±?1.71, 101.75?±?1.44, 105.37?±?4.58 and 96.84?±?0.56, respectively). Percutaneous permeability of flurbiprofen-in-HPβCD-in-gels could be significantly accelerated by turpentine oil and was related to the water content in the system. An in vivo pharmacokinetic study showed a 2-fold increase in Cmax and a shortened Tmax as well as a comparable relative bioavailability when compared with the commercial flurbiprofen Cataplasms (Zepolas®). With their superior dissolution, these flurbiprofen/HPβCD inclusion complexes prepared by SCF processing could provide improved applications for flurbiprofen. 相似文献
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采用原位光学法研究聚酯(PET)/CO2系统的玻璃化转变温度(Tg)与压力间的关系。在温度为50℃~120℃,压力为0.1MPa~20MPa范围内,PET薄膜样品的玻璃化转变温度的降低(Tg)与气体的压力(p)成线性关系,其斜率dTg/dp≈-1.35℃/MPa,上述条件下的最大降幅ΔTg,max=-26.7℃。在30MPa的文献值明显偏离ΔTg~p直线,意味着在高压阶段,静压起主导作用,使PET样品的玻璃化转变温度升高。 相似文献
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以硝酸钙、氯化锶、磷酸氢二氨等为原料,采用溶胶-凝胶-超临界流体干燥法,制备了纳米掺锶羟基磷灰石(SrHAP)。通过元素含量分析、TEM、XRD、FT-IR等手段对其结构进行了表征,分析了锶的掺入对羟基磷灰石(HAP)的结构、晶形及结晶度的影响;研究了HAP掺入锶后对大肠杆菌、金黄色葡萄球茵、乳酸杆菌的抗茵性能。结果表明:采用溶胶-凝胶-超临界CO_2干燥法,可制备结晶性较好的纳米HAP和Sr/[Sr ca]原子比为0.5的纳米SrHAP;在给定的条件下,锶可以按化学计量比掺入到HAP的结构中;HAP掺入锶后,其主要官能团红外光谱吸收峰的振动频率降低,晶形从HAP的短棒状改变为SrHAP的针状,结晶度降低,对大肠杆菌、金黄色葡萄球菌、乳酸杆茵的抗菌性能提高。 相似文献
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纳米掺锶羟基磷灰石的制备及其抗菌性能研究 总被引:6,自引:1,他引:5
以硝酸钙、氯化锶、磷酸氢二氨等为原料,采用溶胶-凝胶-超临界流体干燥法,制备了纳米掺锶羟基磷灰石(SrHAP).通过元素含量分析、TEM、XRD、FT-IR等手段对其结构进行了表征,分析了锶的掺入对羟基磷灰石(HAP)的结构、晶形及结晶度的影响;研究了HAP掺入锶后对大肠杆菌、金黄色葡萄球菌、乳酸杆菌的抗菌性能.结果表明:采用溶胶-凝胶-超临界CO2干燥法,可制备结晶性较好的纳米HAP和Sr/[Sr Ca]原子比为0.5的纳米SrHAP;在给定的条件下,锶可以按化学计量比掺入到HAP的结构中;HAP掺入锶后,其主要官能团红外光谱吸收峰的振动频率降低,晶形从HAP的短棒状改变为SrHAP的针状,结晶度降低,对大肠杆菌、金黄色葡萄球菌、乳酸杆菌的抗菌性能提高. 相似文献