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中空纤维支撑液膜是一种萃取新技术,具有选择性好、重现性好、节省有机溶剂等优点。介绍中空纤维支撑液膜的工作原理、结构以及萃取影响因素,就该技术在药物残留检测方面的应用进行综述。 相似文献
86.
羟基喜树碱自乳化传递系统的处方筛选和体外评价 总被引:1,自引:0,他引:1
筛选和制备羟基喜树碱自乳化传递系统的处方并进行体外评价.以平衡质量浓度方法考察了羟基喜树碱在不同的油相、乳化剂和助乳化剂中的质量浓度,通过三元相图辅助筛选处方的组成,采用星点设计-效应面法优化处方中各组分的比例,筛选和制备了羟基喜树碱自乳化传递系统.考察自乳化制剂的粒径、累积溶出度、自乳化速率、微乳形态及其初步稳定性等.筛选出由m(氢化玉米油)(t) m(辛酸癸酸甘油酯)=1∶1为混合油相,m(聚氧乙烯蓖麻油)(t)m(辛酸葵酸聚乙二醇甘油酯)=2∶1为混合乳化剂,二乙烯基乙二醇单乙醚为助乳化剂和羟基喜树碱组成的自乳化传递系统.所得的优化处方可自发形成均匀球状液滴,微乳平均粒径在30 nm左右且分布窄,自乳化速率在5 min以内,溶出度在60 min内达到90%以上,而且制剂稳定性良好.通过处方研究确定了最优处方,研制了羟基喜树碱自乳化传递系统. 相似文献
87.
Mirzaagha Babazadeh 《应用聚合物科学杂志》2007,104(4):2403-2409
2‐Hydroxyethyl methacrylate was copolymerized with acrylamide, N‐vinyl‐2‐pyrrolidone, and n‐butyl methacrylate by free‐radical solution polymerization with α,α′‐azobisisobutyronitrile as an initiator at 70 ± 1°C. The average molecular weights and molar compositions of the resultant copolymers were determined with gel permeation chromatography and 1H‐NMR spectroscopy data, respectively. Diclofenac or 2‐[(2,6‐dichlorophenyl)amino]benzene acetic acid, a nonsteroidal anti‐inflammatory drug, was chemically attached to the copolymers by transesterification reaction in the presence of N,N′‐dicyclohexylcarbodiimide to give macromolecular prodrugs. All the synthesized polymers were characterized with Fourier transform infrared, 1H‐, and 13C‐NMR spectroscopy techniques. The polymer–drug conjugates were hydrolyzed in cellophane member dialysis bags containing aqueous buffered solutions (pH 8) at 37°C, and the hydrolysis solutions were detected by UV spectrophotometer at selected intervals. The results showed that the drug could be released by selective hydrolysis of the ester bond from the side chain of the drug moiety. The release profiles of the drug indicated that the hydrolytic behavior of polymeric prodrugs strongly depends on the hydrophilicity of the polymer. The results suggest that the synthesized copolymers could be useful carriers for the release of diclofenac in controlled‐release systems. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2403–2409, 2007 相似文献
88.
Differential scanning calorimetry (DSC), FTIR, X‐ray diffraction (XRD), and viscosity methods were used to examine the miscibility, interaction, and degradability of cationic guar gum (GG) and sodium carboxymethylcellulose (NaCMC) in their blend films. The experiment results prove that there exist electrostatic interactions and hydrogen bonding between GG and NaCMC. Blend films degrade quicker than pure GG or NaCMC film. Furthermore, the degradation rate of blend films is related to the interactions between GG and NaCMC. Based on the research of blend films as the drug carriers for Ibuprofen, it is found that the blend composition, initial drug concentration, and pH value affect the drug release and the GG/NaCMC blend films have good sustained release performance. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3553–3559, 2007 相似文献
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Nanoclays for polymer nanocomposites, paints, inks, greases and cosmetics formulations, drug delivery vehicle and waste water treatment 总被引:2,自引:0,他引:2
Hasmukh A. Patel Rajesh S. Somani Hari C. Bajaj Raksh V. Jasra 《Bulletin of Materials Science》2006,29(2):133-145
An overview of nanoclays or organically modified layered silicates (organoclays) is presented with emphasis placed on the
use of nanoclays as the reinforcement phase in polymer matrices for preparation of polymer/layered silicates nanocomposites,
rheological modifier for paints, inks and greases, drug delivery vehicle for controlled release of therapeutic agents, and
nanoclays for industrial waste water as well as potable water treatment to make further step into green environment. A little
amount of nanoclay can alter the entire properties of polymers, paints, inks and greases to a great extent by dispersing 1nm
thick layered silicate throughout the matrices. The flexibility of interlayer spacing of layered silicates accommodates therapeutic
agents which can later on be released to damaged cell. Because the release of drugs in drug-intercalated layered materials
is controllable, these new materials have a great potential as a delivery host in the pharmaceutical field. The problem of
clean water can be solved by treating industrial and municipal waste water with organoclays in combination with other sorbents
like activated carbon and alum. Organoclays have proven to be superior to any other water treatment technology in applications
where the water to be treated contains substantial amounts of oil and grease or humic acid. 相似文献