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Dual ligand-targeted Pluronic P123 polymeric micelles enhance the therapeutic effect of breast cancer with bone metastases
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作者 HUAN GAO JIE ZHANG +5 位作者 TONY GKLEIJN ZHAOYONG WU BING LIU YUJIN MA BAOYUE DING DONGFENG YIN 《Oncology Research》 SCIE 2024年第4期769-784,共16页
Bone metastasis secondary to breast cancer negatively impacts patient quality of life and survival.The treatment of bone metastases is challenging since many anticancer drugs are not effectively delivered to the bone ... Bone metastasis secondary to breast cancer negatively impacts patient quality of life and survival.The treatment of bone metastases is challenging since many anticancer drugs are not effectively delivered to the bone to exert a therapeutic effect.To improve the treatment efficacy,we developed Pluronic P123(P123)-based polymeric micelles dually decorated with alendronate(ALN)and cancer-specific phage protein DMPGTVLP(DP-8)for targeted drug delivery to breast cancer bone metastases.Doxorubicin(DOX)was selected as the anticancer drug and was encapsulated into the hydrophobic core of the micelles with a high drug loading capacity(3.44%).The DOX-loaded polymeric micelles were spherical,123 nm in diameter on average,and exhibited a narrow size distribution.The in vitro experiments demonstrated that a pH decrease from 7.4 to 5.0 markedly accelerated DOX release.The micelles were well internalized by cultured breast cancer cells and the cell death rate of micelle-treated breast cancer cells was increased compared to that of free DOX-treated cells.Rapid binding of the micelles to hydroxyapatite(HA)microparticles indicated their high affinity for bone.P123-ALN/DP-8@DOX inhibited tumor growth and reduced bone resorption in a 3D cancer bone metastasis model.In vivo experiments using a breast cancer bone metastasis nude model demonstrated increased accumulation of the micelles in the tumor region and considerable antitumor activity with no organ-specific histological damage and minimal systemic toxicity.In conclusion,our study provided strong evidence that these pH-sensitive dual ligand-targeted polymeric micelles may be a successful treatment strategy for breast cancer bone metastasis. 展开更多
关键词 Pluronic micelles Targeted nanotherapeutics Nanoparticulate drug delivery system Breast cancer with bone metastasis Therapeutic efficacy
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Mass transfer process of peanut protein extracted by bis(2-ethylhexyl)sodium sulfosuccinate reverse micelles
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作者 Chenxian Yang Tianci Li +5 位作者 Tingwei Zhu Xiaojie Duan Yibao Chen Yandong Xu Fusheng Chen Kunlun Liu 《Grain & Oil Science and Technology》 CAS 2024年第1期60-67,共8页
The liquid-liquid extraction method using reverse micelles can simultaneously extract lipid and protein of oilseeds,which have become increasingly popular in recent years.However,there are few studies on mass transfer... The liquid-liquid extraction method using reverse micelles can simultaneously extract lipid and protein of oilseeds,which have become increasingly popular in recent years.However,there are few studies on mass transfer processes and models,which are helpful to better control the extraction process of oils and proteins.In this paper,mass transfer process of peanut protein extracted by bis(2-ethylhexyl)sodium sulfosuccinate(AOT)/isooctane reverse micelles was investigated.The effects of stirring speed(0,70,140,and 210 r/min),temperature of extraction(30,35,40,45,and 50℃),peanut flour particle size(0.355,0.450,0.600,and 0.900 mm)and solidliquid ratio(0.010,0.0125,0.015,0.0175,and 0.020 g/mL)on extraction rate were examined.The results showed that extraction rate increased with temperature rising,particle size reduction as well as solid-liquid ratio increase respectively,while little effect of stirring speed(P>0.05)was observed.The apparent activation energy of extraction process was calculated as 10.02 kJ/mol and Arrhenius constant(A)was 1.91 by Arrhenius equation.There was a linear relationship between reaction rate constant and the square of the inverse of initial particle radius(1/r_(0)^(2))(P<0.05).This phenomenon and this shrinking core model were anastomosed.In brief,the extraction process was controlled by the diffusion of protein from the virgin zone interface of particle through the reacted zone and it was in line with the first order reaction.Mass transfer kinetics of peanut protein extracted by reverse micelles was established and it was verified by experimental results.The results provide an important theoretical guidance for industrial production of peanut protein separation and purification. 展开更多
关键词 AOT reverse micelles Peanut protein KINETICS Shrinking core model Mass transfer
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TR-ESR Investigation on Reaction of Vitamin C with Excited Triplet of 9,10-phenanthrenequinone in Reversed Micelle Solutions 被引量:1
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作者 许新胜 史蕾 +2 位作者 刘毅 季学韩 崔执凤 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第2期150-154,I0003,共6页
Time-resolved electron spin resonance has been used to study quenching reactions between the antioxidant Vitamin C (VC) and the triplet excited states of 9,10-phenanthrenequinone (PAQ) in ethylene glycol-water (E... Time-resolved electron spin resonance has been used to study quenching reactions between the antioxidant Vitamin C (VC) and the triplet excited states of 9,10-phenanthrenequinone (PAQ) in ethylene glycol-water (EG-H2O) homogeneous and inhomogeneous reversed micelle solutions. Reversed micelle solutions were used to be the models of physiological environment of biological cell and tissue. In PAQ/EG-H2O homogeneous solution, the excited triplet of PAQ (3PAQ*) abstracts hydrogen atom from solvent EG. In PAQ/VC/EG-H2O solution, 3pAQ* abstracts hydrogen atom not only from solvent EG but also from VC. The quenching rate constant of 3pAQ* by VC is close to the diffusion-controlled value of 1.41 × 108 L/(mol.s). In hexadecyltrimethylammonium bromide (CTAB)/EG-H2O and aerosol OT (AOT)/EG- H2O reversed micelle solutions, 3pAQ* and VC react around the water-oil interface of the reversed micelle. Exit of 3pAQ* from the lipid phase slows down the quenching reaction. For Triton X-100 (TX-100)/EG-H2O reversed micelle solution, PAQ and VC coexist inside the hydrophilic polyethylene glycol core, and the quenching rate constant of 3pAQ* by VC is larger than those in AOT/EG-H2O and CTAB/EG-H2O reversed micelle solutions, even a little larger than that in EG-H2O homogeneous solution. The strong emissive chemically induced dynamic electron polarization of As'- resulted from the effective TM spin polarization transfer in hydrogen abstraction of 3pAQ* from VC. 展开更多
关键词 9 10-phenanthrenequinone Vitamin C Time-resolved electron spin resonance Reversed micelle
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pH-sensitive polymeric micelles triggered drug release for extracellular and intracellular drug targeting delivery 被引量:11
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作者 Yanhua Liu Wenping Wang +2 位作者 Jianhong Yang Chengming Zhou Jin Sun 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2013年第3期159-167,共9页
Most of the conventional chemotherapeutic agents used for cancer chemotherapy suffer from multidrug resistance of tumor cells and poor antitumor efficacy.Based on physiological differences between the normal tissue an... Most of the conventional chemotherapeutic agents used for cancer chemotherapy suffer from multidrug resistance of tumor cells and poor antitumor efficacy.Based on physiological differences between the normal tissue and the tumor tissue,one effective approach to improve the efficacy of cancer chemotherapy is to develop pH-sensitive polymeric micellar delivery systems.The copolymers with reversible protonationedeprotonation core units or acid-liable bonds between the therapeutic agents and the micelle-forming copolymers can be used to form pH-sensitive polymeric micelles for extracellular and intracellular drug smart release.These systems can be triggered to release drug in response to the slightly acidic extracellular fluids of tumor tissue after accumulation in tumor tissues via the enhanced permeability and retention effect,or they can be triggered to release drug in endosomes or lysosomes by pH-controlled micelle hydrolysis or dissociation after uptake by cells via the endocytic pathway.The pH-sensitive micelles have been proved the specific tumor cell targeting,enhanced cellular internalization,rapid drug release,and multidrug resistance reversal.The multifunctional polymeric micelles combining extracellular pH-sensitivity with receptor-mediated active targeting strategies are of great interest for enhanced tumor targeting.The micelles with receptor-mediated and intracellular pH targeting functions are internalized via receptor-mediated endocytosis followed by endosomal-pH triggered drug release inside the cells,which reverses multidrug resistance.The pH sensitivity strategy of the polymeric micelles facilitates the specific drug delivery with reduced systemic side effects and improved chemotherapeutical efficacy,and is a novel promising platform for tumor-targeting drug delivery. 展开更多
关键词 pH-sensitive polymeric micelles Tumor extracellular pH targeting Tumor intracellular pH targeting Multifunctional polymeric micelles MDR reversion
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Effect of polyoxypropylene chain length on the critical micelle concentration of propylene oxide-ethylene oxide block copolymers
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作者 张治国 尹红 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第3期219-221,共3页
In this work, the surface activity of block copolymer nonionic surfactants (RPE) has been determined, i.e., critical micelle concentration (CMC), surface excess concentration (Γ), surface area demand per molecule (A)... In this work, the surface activity of block copolymer nonionic surfactants (RPE) has been determined, i.e., critical micelle concentration (CMC), surface excess concentration (Γ), surface area demand per molecule (A), surface tension at CMC (γCMC). A linear decrease of ln[CMC] vs number of oxypropylene units in copolymer molecule was observed. The change in the work of cohesion per oxypropylene group when passing from molecular into micellar state, calculated from the Shinoda equation, was 0.43kT for the studied compounds. 展开更多
关键词 Nonionic surfactant Propylene oxide-ethylene oxide block copolymers Critical micelle concentration micellIZATION
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Preparation and Unimolecular-Micellization Behavior of Homopolymer of Surface-Active Monomer AMC14AB
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作者 Kang-kai Liu Lei Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第5期469-475,共7页
(2-acrylamido) ethyl tetradecyl dimethylammonium bromide (AMC14AB) was polymerized in aqueous solu- tion to form the homopolymer P(AMC14AB). The physicochemical properties of P(AMC14AB) in aqueous solution wer... (2-acrylamido) ethyl tetradecyl dimethylammonium bromide (AMC14AB) was polymerized in aqueous solu- tion to form the homopolymer P(AMC14AB). The physicochemical properties of P(AMC14AB) in aqueous solution were mainly studied with fluorescent probe method, surface tension measurement and conductom- etry. The experimental results show that the aggregation morphology of P(AMC14AB) in aqueous solution is unimolecular micelle as expected. Being different from conventional multimolecular micelle systems, the unimolecular micelle system of P(AMC14AB) not only shows critical micellar concentration (CMC=0), (i.e. once added to pure water, the surface tension decreases immediately in spite how small the density is), but also the surface tension stays almost the same with the concentration increasing. That is to say, there is no mutational point on the relationship curve between surface tension and concentration. Furthermore, the unimolecular micelle system of P(AMC14AB) has no Krafft temperature, i.e. at any temperature, so long as it is dissolved in water, the unimolecular micelles will form. Besides this, for the solubilization of hydrophobic organic substances, the unimolecular micelle system of P(AMC14AB) is obviously different from the common multimolecular micelle system, having no turning point on the relationship curve between toluene solubi- lizaion amount and P(AMC14AB) concentration, and the solubilizing ability of the unimolecular-micelle system of P(AMC14AB) for hydrophobic organic substances is much higher than that of the conventional multimolecular micelle solutions of common surfactants, such as centyl trimethyl ammonium bromide. 展开更多
关键词 Surface active monomer Unimolecular micelle Zero critical micellar concentration Krafft temperature
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Enantioselective Hydrolysis of α-Amino Acid Ester by Chiral Metallomicelles
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作者 Jing Song YOU Xiao Qi YU Xiao Ling ZHANG and Ru Gang XIE(Department of Chemistry, Sichuan University, Chengdu 610064) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第4期335-337,共3页
A series of chiral lipophilic Cu(Ⅱ) complexes were investigated as catalysts for the enantioselective hydrolysis of R(S)-p-nitrophenyl N-dodecanoyl-phenylalaninate in micelles. The highest enantioselectivity (kR/ks=7... A series of chiral lipophilic Cu(Ⅱ) complexes were investigated as catalysts for the enantioselective hydrolysis of R(S)-p-nitrophenyl N-dodecanoyl-phenylalaninate in micelles. The highest enantioselectivity (kR/ks=7. 81) was observed in a mixed micellar system composed of 1-Cu(Ⅱ) and Brij35. 展开更多
关键词 micellE chiral metallomicelle enantioselective hydrolysis
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New Development of Reverse Micelles and Applications in Protein Separation and Refolding 被引量:9
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作者 刘杨 董晓燕 孙彦 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第6期949-955,共7页
Reverse micelles bring mild and effective microenvironments in organic solvent that contain bitmolecules, which have attracted immense attention for application in the isolation of proteins, protein refolding, and enz... Reverse micelles bring mild and effective microenvironments in organic solvent that contain bitmolecules, which have attracted immense attention for application in the isolation of proteins, protein refolding, and enzymatic reaction. In this review, the application of reverse micelles for protein separation and refolding has been briefly summarized and various reverse micellar systems composed of different surfactants, including ionic, non- ionic, mixed, and affinity-based reverse micelles, have been highlighted. It illustrates especially the potential application of the novel affinity-based reverse micelles consisting of biocompatible surfactant coupled with affinity ligands. Moreover, the importance to develop universal affinity-based reverse micelles for protein separation and refolding in the downstream processing of biotechnology has been pointed out. 展开更多
关键词 reverse micelles ionic surfactant nonionic surfactant AFFINITY protein separation protein refolding
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Enhanced oil recovery by nonionic surfactants considering micellization, surface, and foaming properties 被引量:8
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作者 Achinta Bera Ajay Mandal +1 位作者 Hadi Belhaj Tarkeswar Kumar 《Petroleum Science》 SCIE CAS CSCD 2017年第2期362-371,共10页
Surfactants for enhanced oil recovery are important to study due to their special characteristics like foam generation,lowering interfacial tension between oleic and aqueous phases,and wettability alteration of reserv... Surfactants for enhanced oil recovery are important to study due to their special characteristics like foam generation,lowering interfacial tension between oleic and aqueous phases,and wettability alteration of reservoir rock surfaces.Foam is a good mobility control agent in enhanced oil recovery for improving the mobility ratio.In the present work,the foaming behavior of three nonionic ethoxylated surfactants,namely Tergitol 15-S-7,Tergitol 15-S-9,and Tergitol 15-S-12,was studied experimentally.Among the surfactants,Tergitol 15-S-12 shows the highest foamability.The effect of Na Cl concentration and synthetic seawater on foaming behavior of the surfactants was investigated by the test-tube shaking method.The critical micelle concentrations of aqueous solutions of the different nonionic surfactants were measured at 300 K.It was found that the critical micelle concentrations of all surfactants also increased with increasing ethylene oxide number.Dynamic light scattering experiments were performed to investigate the micelle sizes of the surfactants at their respective critical micelle concentrations.Core flooding experiments were carried out in sand packs using the surfactant solutions.It was found tha t22% additional oil was recovered in the case of all the surfactants over secondary water flooding.Tergitol 15-S-12exhibited the maximum additional oil recovery which is more than 26%after water injection. 展开更多
关键词 Enhanced oil recovery Ethylene oxide number Foaming properties Surfactant flooding micellization
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Synthesis and evaluation of cationic polymeric micelles as carriers of lumbrokinase for targeted thrombolysis 被引量:6
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作者 Yang Pan Xiahui Wang Zongning Yin 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2019年第2期144-153,共10页
To achieve targeted thrombolysis, a targeted delivery system of lumbrokinase(LK) was constructed using RGDfk-conjugated hybrid micelles. Based on the specific affinity of RGDfk to glycoprotein complex of GP Ⅱ b/Ⅲ a ... To achieve targeted thrombolysis, a targeted delivery system of lumbrokinase(LK) was constructed using RGDfk-conjugated hybrid micelles. Based on the specific affinity of RGDfk to glycoprotein complex of GP Ⅱ b/Ⅲ a expressed on the surface of membrane of activated platelet, LK loaded targeted micelles(LKTM) can be delivered to thrombus. The hybrid micelles were composed of polycaprolactone-block-poly(2-(dimethylamino) ethyl methacrylate)(PCL-PDMAEMA), methoxy polyethylene glycol-block-polycaprolactone(mPEG-PCL)and RGDfk conjugated polycaprolactone-block-polyethylene glycol(PCL-PEG-RGDfk). PCLPDMAEMA was synthesized via ring open polymerization(ROP) and atom transfer radical polymerization(ATRP). PCL-PEG-RGDfk was synthesized via ROP and carbodiimide chemistry. The prepared LKTM was characterized by dynamic light scattering(DLS) and transmission electron microscope(TEM). Colloidal stability assay showed the prepared LKTM was stable. Biocompatibility assay was performed to determine the safe concentration range of polymer. The assay of fluorescent distribution in vivo demonstrated that LKTM can be efficiently delivered to thrombi in vivo. Thrombolysis in vivo indicated the thrombolytic potency of LKTM was optimal in all groups. Notably, the laboratory mice treated with LKTM exhibited a significantly shorter tail bleeding time compared to those treated with LK or LK-loaded micelles without RGDfk, which suggested that the targeted delivery of LK using RGDfk-conjugated hybrid micelles effectively reduced the bleeding risk. 展开更多
关键词 TARGETED THROMBOLYSIS LUMBROKINASE Polymeric micelles ATRP ROP
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Preparation and evaluation of poly(L-histidine) based pH-sensitive micelles for intracellular delivery of doxorubicin against MCF-7/ADR cells 被引量:6
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作者 Nan Jia Yuqing Ye +4 位作者 Qi Wang Xiuli Zhao Haiyang Hu Dawei Chen Mingxi Qiao 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2017年第5期433-441,共9页
In this study, a p H-sensitive micelle self-assembled from poly(L-histidine) based triblock copolymers of poly(ethylene glycol)–poly(D,L-lactide)–poly(L-histidine)(mPEG-PLA-PHis) was prepared and used as the intrace... In this study, a p H-sensitive micelle self-assembled from poly(L-histidine) based triblock copolymers of poly(ethylene glycol)–poly(D,L-lactide)–poly(L-histidine)(mPEG-PLA-PHis) was prepared and used as the intracellular doxorubicin(Dox) delivery for cancer chemotherapy. Dox was loaded into the micelles by thin-film hydration method and a Box–Behnken design for three factors at three levels was used to optimize the preparations. The optimized mPEG-PLA-Phis/Dox micelles exhibited good encapsulation efficiency of 91.12%,a mean diameter of 45 nm and narrow size distribution with polydispersity index of 0.256.In vitro drug release studies demonstrated that Dox was released from the micelles in a p Hdependent manner. Furthermore, the cellular evaluation of Dox loaded micelles displayed that the micelles possessed high antitumor activity in vitro with an IC50 of 35.30 μg/ml against MCF-7/ADR cells. The confocal microscopy and flow cytometry experiments indicated that m PEG-PLA-Phis micelles mediated efficient cytoplasmic delivery of Dox with the aid of poly(Lhistidine) mediated endosomal escape. In addition, blank m PEG-PLA-Phis micelles were shown to be nontoxic to MCF-7/ADR cells even at a high concentration of 200 μg/ml. The pHsensitive mPEG-PLA-PHis micelles have been demonstrated to be a promising nanosystem for the intracellular delivery of Dox for MDR reversal. 展开更多
关键词 Doxorubicin(Dox) mPEG-PLA-Phis pH SENSITIVE micelles Box–Behnken design
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Supersaturation induced by Itraconazole/Soluplus micelles provided high GI absorption in vivo 被引量:4
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作者 Yue Zhong Guanghui Jing +6 位作者 Bin Tian Hao Huang Yuanyuan Zhang Jingxin Gou Xing Tang Haibing He Yanjiao Wang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2016年第2期255-264,共10页
To investigate the effect of supersaturation induced by micelle formation during dissolution on the bioavailability of itraconazole(ITZ)/Soluplus~? solid dispersion. Solid dispersions prepared by hot melt extrusion (H... To investigate the effect of supersaturation induced by micelle formation during dissolution on the bioavailability of itraconazole(ITZ)/Soluplus~? solid dispersion. Solid dispersions prepared by hot melt extrusion (HME) were compressed into tablets directly with other excipients. Dissolution behavior of ITZ tablets was studied by dissolution testing and the morphology of micelles in dissolution media was studied using transmission electron microscopy (TEM). Drug transferring from stomach into intestine was simulated to obtain a supersaturated drug solution. Bioavailability studies were performed on the ITZ tablets and Sporanox~? in beagle dogs. The morphology of micelles in the dissolution media was observed to be spherical in shape, with an average size smaller than 100 nm. The supersaturated solutions formed by Soluplus~? micelles were stable and no precipitation took place over a period of 180 min. Compared with Sporanox~?, ITZ tablets exhibited a 2.50-fold increase in the AUC (0–96) of ITZ and a 1.95-fold increase in its active metabolite hydroxyitraconazole (OHITZ) in the plasma of beagle dogs. The results obtained provided clear evidence that not only the increase in the dissolution rate in the stomach, but also the supersaturation produced by micelles in the small intestine may be of great assistance in the successful development of poorly water-soluble drugs. The micelles formed by Soluplus~? enwrapped the molecular ITZ inside the core which promoted the amount of free drug in the intestinal cavity and carried ITZ through the aqueous boundary layer(ABL), resulting in high absorption by passive transportation across biological membranes. The uptake of intact micelles through pinocytosis together with the inhibition of P-glycoprotein-mediated drug efflux in intestinal epithelia contributed to the absorption of ITZ in the gastrointestinal tract. These results indicate that HME with Soluplus~?, which can induce supersaturation by micelleformation, may be of great assistance to the successful development of poorly watersoluble drugs. 展开更多
关键词 Solid dispersion ITRACONAZOLE TABLETS Hot MELT extrusion SUPERSATURATION micelles BIOAVAILABILITY
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Rheological properties of wormlike micelles formed in the sodium oleate/trisodium phosphate aqueous solution 被引量:4
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作者 Yong Qiang Ji Wei Shan Wang +1 位作者 Gan Zuo Li Li Qiang Zheng 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第4期483-487,共5页
Aqueous solution of anionic surfactant,sodium oleate(NaOA),was studied by means of steady-state shear rheology and dynamic oscillatory technique.The system of NaOA/Na3PO4 showed high viscosity,strong viscoelasticity... Aqueous solution of anionic surfactant,sodium oleate(NaOA),was studied by means of steady-state shear rheology and dynamic oscillatory technique.The system of NaOA/Na3PO4 showed high viscosity,strong viscoelasticity and good ability of countering Ca^2+,Mg^2+.The Maxwell model and Cole-Cole plot were applied to study the dynamic viscoelasticity of wormlike micelles.The microstructures of the wormlike micelles were characterized by FF-TEM. 展开更多
关键词 Wormlike micelles RHEOLOGY Sodium oleate Trisodium phosphate
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Effect of Cu(11)-Salicylate in Micellar Systems onScavenging Superoxide Ion Released by CulturedMacrophages
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作者 应宇辉 张颖 鲁纯素 《Journal of Chinese Pharmaceutical Sciences》 CAS 1995年第1期30-36,共7页
基于胶束与球状蛋白的相似性,用胶束模拟超氧化物歧化酶(SOD)的微环境,以促进SOD模拟物─水杨酸铜络合物对O歧化的催化作用,达到清除O_2的目的。本文首次用培养的巨噬细胞受刺激产生的“呼吸暴发”为O的发生源,研究了... 基于胶束与球状蛋白的相似性,用胶束模拟超氧化物歧化酶(SOD)的微环境,以促进SOD模拟物─水杨酸铜络合物对O歧化的催化作用,达到清除O_2的目的。本文首次用培养的巨噬细胞受刺激产生的“呼吸暴发”为O的发生源,研究了在CTAB、SDS、TritonX-100及Tween20胶束体系中水杨酸铜络合物对O的清除作用。研究结果表明,以水杨酸铜-SDS胶束体系对O的清除率最高,达90.4%。其他胶束体系对O的歧化亦均有促进作用。 展开更多
关键词 Superoxide radical anion SOD-like activity Cu(Ⅱ)-salicylate micellE
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Selective Affinity Separation of Yeast Alcohol Dehydrogenase by Reverse Micelles with Unbound Triazine Dye 被引量:4
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作者 张天喜 刘会洲 陈家镛 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第3期314-318,共5页
The reversed micelles were formed with cationic cetyltrimethylammonium bromide (CTAB) as surfactant and n-hexanol as cosolvent in the CTAB (50mmol.L-1)/hexanol (15% by volume)/hexane system. Cibacron Blue 3GA (CB) as ... The reversed micelles were formed with cationic cetyltrimethylammonium bromide (CTAB) as surfactant and n-hexanol as cosolvent in the CTAB (50mmol.L-1)/hexanol (15% by volume)/hexane system. Cibacron Blue 3GA (CB) as an affinity ligand in the aqueous phase was directly introduced to the reversed micelles with electrostatic interaction between anionic CB and cationic surfactant. High molecular weight (Mr) protein, yeast alcohol dehydrogenase (YADH, Mr = 141000) from baker's yeast, has been purified using the affinity reversed micelles by the phase transfer method. Various parameters, such as CB concentration, pH and ionic strength, on YADH forward and backward transfer were studied. YADH can be transferred into and out from the reversed micelles under mild conditions (only by regulation of solution pH and salt concentration) with the successful recovery of most YADH activity. Both forward and backward extractions occurred when the aqueous phase pH>pI with electrostatic attraction between YADH and CTAB. The recovery of YADH activity and purification factor have been improved with addition of a small amount of affinity CB. The recovery of YADH activity obtained was ~99% and the purification factor was about 4.0-fold after one cycle of full forward and backward extraction. The low ionic strength in the initial aqueous phase might be responsible for the YADH transfer into the reversed micellar phase. 展开更多
关键词 reversed micelles yeast alcohol dehydrogenase protein purification affinity technology cetyltrimethy- lammonium bromide
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Factors Affecting Trypsin Extraction by AOT Reversed Micelles and Observation by STM 被引量:3
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作者 周小华 翁亚军 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第3期407-412,共6页
In this article, the influence factors of trypsin extracted from crude pancreatin was investigated, and scanning turmeling microscope(STM) was used to observe the image of trypsin in butane-diacid-2-ethyl-hexyl-este... In this article, the influence factors of trypsin extracted from crude pancreatin was investigated, and scanning turmeling microscope(STM) was used to observe the image of trypsin in butane-diacid-2-ethyl-hexyl-ester-sulfonic sodium (AOT)/iso-octane reversed micelles. The STM image showed that trypsins bounded in reversed micelles was rigid, which weakened its conjugative effect and caused maximum ultraviolet absorption and fluorescence emissive absorption moving toward blue waves. AOT concentration, pH and cations were the main influence factors of extraction. Specifically, extraction percentage of trypsin decreased with the increase of AOT concentration from 0.01 to 0.1mol·L^-1. When pH value is from 5.30 to 10.0, i.e. less than pI of trypsin, the extraction percentage is raised with the different increase of pI-pH, but when the pH value is less than 5.20, the extraction percentage is decreased with the acidity added. Besides, the extraction efficiency is negative, related with the concentrations of Ca^2+, Na^+, K^+ which were in the range of 0.2-1.0mol.L^-1, and influence of concentration of Ca^2+ is greater than that of Na^+, and K^+ which has the minimum impact with the same concentration. Finally, optimum conditions to extract trypsin were: AOT reversed micelles 0.05mol·L^-1, trypsin concentration in crude pancreatin solution 3mg·ml^-1, pH 5.2-- 5.3, ratio (by volume) of extraction phase to strip-extraction phase 1 : 1, and time of 5min. The corresponding percentage of extraction was 22.7% and specific activity was 78.9 N-benzoyl-L-arginlne ethyl ester (BAEE) U·mg^-1 protein, three times than that in crude pancreatin. There was no lipase and amylopsin activity was decreased to 1/5 of crude pancreatin. Partly purifying solution was treated by condition mentioned above with 0.05mol·L^-1 ceryl-trimethyl-ammonium bromide (CTAB), total extraction percentage of trypsin was 74.18% and specific activity was 3148.3 BAEE U·mg^-1, i.e. 48.16 times purer than that in crude pancreatin. Through sodium dodecyl sulfate-polyacryl amide gel electrophoresis (SDS-PAGE) and image analysis of extracted product, there were only three bands in the trypsin, while seven in crude pancreatin, and electrophoresis location of main bend was almost identical with the standard enzyme. 展开更多
关键词 AOT reversed micelles EXTRACTION TRYPSIN scanning TUNNELING microscope(STM)
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EPR Effect of Amphiphilic Copolymer Micelles Observed by Fluorescent Imaging 被引量:4
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作者 LIU Tong-jun LIU Shi +3 位作者 HU Xiu-li SHENG Shi-hou HUANG Yu-bin JING Xia-bin 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第4期628-634,共7页
Enhanced permeation and retention(EPR) targeting effect of rhodamine B labeled PEG-b-P(LA-co-DHP) [PEG:poly(ethylene glycol);LA:L-lactide;DHP:2,2-dihydroxylmethyl-propylene carbonate] micelles(RhB-micelles)... Enhanced permeation and retention(EPR) targeting effect of rhodamine B labeled PEG-b-P(LA-co-DHP) [PEG:poly(ethylene glycol);LA:L-lactide;DHP:2,2-dihydroxylmethyl-propylene carbonate] micelles(RhB-micelles) was observed in H22 liver cancer bearing mice.The RhB-micelles were prepared by conjugating rhodamine B with the DHP units of amphiphilic block copolymer PEG-b-P(LA-co-DHP) followed by subsequent self-assembling of the conjugate.The parent copolymer PEG-b-P(LA-co-DHP) was synthesized by ring-opening copolymerization of LA and DHP with PEG as macroinitiator and diethyl zinc(ZnEt2) as catalyst.The micelles have a spherical shape and the average diameter is ca.50 nm by TEM(transmission electron microscope) or 80 nm by DLS(dynamic light scattering).Their in vitro cell uptake experiment by CLSM(confocal laser scanning microscopy) and flow cytometry showed preferential internalization of micelles by MCF-7 human breast cancer cells to free RhB.The in vivo tests by live animal imaging and ex vivo excised organ imaging showed that after vena tail injection,free RhB molecules were distributed in the whole body through the circulation system and then gradually metabolized and excreted and there was no preferential partition in tumor bed from the beginning to the end.But the RhB-micelles were preferentially distributed to the tumor bed so that their concentration(fluorescent intensity) in tumor bed got the level of the liver at a certain time point between 1 and 6 h and reached a maximum relative intensity at around 12 h,indicating an obvious EPR effect of RhB-micelles in H22 liver cancer. 展开更多
关键词 Enhanced permeability and retention(EPR) effect Fluorescent imaging micellE Passive targeting
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Improved Anti-tumor Efficiency against Prostate Cancer by Docetaxel-loaded PEG-PCL Micelles 被引量:4
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作者 金明姬 朴圣君 +3 位作者 金铁雄 金哲虎 尹学哲 高钟镐 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第1期66-75,共10页
This study primarily focused on the systematic assessment of both in vitro and in vivo anti-tumor effects of docetaxel-loaded polyethylene glycol(PEG)2000-polycaprolactone(PCL)2600 micelles on hormone-refractory p... This study primarily focused on the systematic assessment of both in vitro and in vivo anti-tumor effects of docetaxel-loaded polyethylene glycol(PEG)2000-polycaprolactone(PCL)2600 micelles on hormone-refractory prostate cancer(HRPC). By using solvent evaporation method, PEG-PCL was chosen to prepare doxetaxel(DTX)-loaded mPEG-PCL micelles(DTX-PMs), with the purpose of eliminating side effects of the commercial formulation(Tween 80) and prolonging the blood circulation time. The prepared DTX-PMs had an average particle size of 25.19±2.36 nm, a zeta potential of 0.64±0.15 mV, a polydispersity index of 0.56±0.03, a drug loading of(8.72±1.05)%, and an encapsulation efficiency of(98.1±8.4)%. In vitro cytotoxicity studies indicated that DTX-PMs could effectively kill LNCap-C4-2B cells and show a dose- and time-dependent efficacy. The hemolysis test showed that DTX-PMs had less hemocytolysis than the commercial product of Duopafei. A sustained in vitro release behavior and prolonged circulation time in blood vessels were observed in the DTX-PMs. Furthermore, when compared with Duopafei, the DTX-PMs dramatically reduced the prostate specific antigen(PSA) level and tumor growth of prostate tumor-bearing nude mice in vivo. In conclusion, the DTX-PMs can lower systemic side effects, improve anti-tumor activity with prolonged blood circulation time, and will bring an alternative to patients with HRPC. 展开更多
关键词 hormone-refractory prostate cancer LNCap-C4-2B DOCETAXEL polymeric micelles
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Rheological properties of novel viscoelastic micelle systems containing anionic-nonionic dimeric surfactant 被引量:2
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作者 方波 曹丹红 江体乾 《Journal of Central South University》 SCIE EI CAS 2008年第S1期176-180,共5页
The viscoelastic micelle systems formed by novel anionic-nonionic dimeric surfactant and conventional cationic surfactant cetyltrimethylammonium(1631) were studied.The viscoelasticity,thixotropy,flow curves and consti... The viscoelastic micelle systems formed by novel anionic-nonionic dimeric surfactant and conventional cationic surfactant cetyltrimethylammonium(1631) were studied.The viscoelasticity,thixotropy,flow curves and constitutive equation for the novel viscoelastic micelle systems were investigated.The results show that the micelle systems possess viscoelasticity,thixotropy,and shear thinning property.Some micelle systems possess hysteresis loops showing both viscoelasticity and thixotropy.It is proved that the flow curves are characterized by the co-rotational Jeffreys constitutive equation correctly. 展开更多
关键词 DIMERIC surfactant viscoelastic micellE clean FRACTURING fluid CONSTITUTIVE equation
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Iron(Ⅱ) tetrasulfophthalocyanine mimetic enzymatic synthesis of conducting polyaniline in micellar system 被引量:2
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作者 胡兴 刘惠 邹国林 《Journal of Central South University》 SCIE EI CAS 2009年第5期743-748,共6页
Iron(Ⅱ) tetrasulfophthalocyanine(FeTSPc) ,as a novel mimetic enzyme of peroxidase,was used in the synthesis of a conducting polyaniline(PANI) /sodium dodecylsulfate(SDS) complex in SDS aqueous micellar solutions. The... Iron(Ⅱ) tetrasulfophthalocyanine(FeTSPc) ,as a novel mimetic enzyme of peroxidase,was used in the synthesis of a conducting polyaniline(PANI) /sodium dodecylsulfate(SDS) complex in SDS aqueous micellar solutions. The effects of pH,concentrations of aniline,SDS and H2O2,and reaction time on polymerization of aniline were studied in this case as shown by UV-Vis absorption spectroscopy. The results show that a wide range of pH(0.5-4.0) is required to produce the conducting PANI,and the optimal pH is 1.0 in SDS micelle. The optimal concentrations of aniline,SDS and H2O2 in feed,and reaction time in this case for the production of conducting PANI are respectively 10 mmol/L,10 mmol/L,25 mmol/L,and 15 h. FT-IR spectrum,elemental analysis,conductivity,cyclic voltammetry and thermogravimetric analysis confirm the thermal stability and electroactive form of PANI. 展开更多
关键词 iron( tetrasulfophthalocyanine POLYANILINE mimetic enzyme CONDUCTIVITY micellE
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