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Preparation of poly(lactide-co-glycolide)microspheres and evaluation of pharmacokinetics and tissue distribution of BDMC-PLGA-MS in rats 被引量:4
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作者 Guozhuan Li Liang Yao +3 位作者 Jing Li Xiaoyan Qin Zhen Qiu Weidong Chen 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2018年第1期82-90,共9页
The aim of the present study was to develop a novel long-acting Poly(lactic-co-glycolic acid)(PLGA)-based microspheres formulation of Bisdemethoxycurcum(BDMC) by emulsionsolvent evaporation method. Meanwhile, the effe... The aim of the present study was to develop a novel long-acting Poly(lactic-co-glycolic acid)(PLGA)-based microspheres formulation of Bisdemethoxycurcum(BDMC) by emulsionsolvent evaporation method. Meanwhile, the effects of the volume ratio of the dispersed phase and continuous phase, the concentration of PLGA and PVA, the theoretical drug loading and stirring speed were investigated. The mean diameter of the microspheres was 8.5 μm and the size distribution was narrow. The encapsulation efficiency(EE) and drug loading efficiency(DLE) of BDME loaded PLGA microspheres(BDMC-PLGA-MS) was 94.18% and 8.14%,respectively. In an in vitro study of drug release, it can be concluded that the BDMC-PLGAMS exhibited sustained and long-term release properties for 96 h. Stability studies suggested that the microspheres we prepared had a very good stability. Furthermore, the results of an in vivo study indicated that the BDMC-PLGA-MS had sustained release effect and was mainly distributed in the lung tissue, and less distribution in other tissues, which indicated that microspheres could be an effective parenteral carrier for the delivery of BDMC in lung cancer treatment. 展开更多
关键词 BISDEMETHOXYCURCUMIN microspherE poly (lactic-co-glycolic acid) Solvent evaporation method PHARMACOKINETICS
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Poly(lactic acid)-aspirin microspheres prepared via the traditional and improved solvent evaporation methods and its application performances 被引量:1
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作者 Xiaolin Pan Mengyuan Gao +3 位作者 Yun Wang Yanping He Tian Si Yanlin Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第8期194-204,共11页
Drug-loaded microspheres are significant for the development of modern pharmaceutical products. It is well known that the taken of aspirin for long-term increases the risk of serious gastrointestinal complications, th... Drug-loaded microspheres are significant for the development of modern pharmaceutical products. It is well known that the taken of aspirin for long-term increases the risk of serious gastrointestinal complications, therefore a controllable delivery of aspirin is of importance to lighten those side effects. In this work, poly(lactic acid)(PLA) was chosen as the carrier to prepare PLA-aspirin microspheres by using the traditional and the improved solvent evaporation methods. It was found that no matter which experimental condition was, the encapsulation efficiency of aspirin was higher by using the improved method than that of the traditional method. Specifically, when the concentration of polyvinyl alcohol = 1%(mass),the polymer concentration = 1:20, the oil/water rate = 1:2.5, PLA-aspirin microspheres were obtained via the improved method with a high yield of 82.83%(mass) and an encapsulation efficiency of 44.09%. PLAaspirin microspheres were then prepared continuously using the improved method, which further enhanced the encapsulation efficiency to 54.56%. Approximate 85% aspirin released from microspheres within 7 days. Obvious degradation which was represented by reduction on hardness was observed by soaking microspheres in PBS for 60 days. This work is of interest because it provides a continuous route to prepare PLA-aspirin microspheres continuously with a high drug encapsulation efficiency. 展开更多
关键词 ASPIRIN Degradation Foam-transfer microspheres poly(lactic acid) Slow-release
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PREPARATION OF POLY(ETHYLENEGLYCOL-co-ACRYLIC ACID) MICROSPHERES WITH DIVINYLBENZNE AS CROSSLINKER BY DISTILLATION-PRECIPITATION POLYMERIZATION 被引量:1
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作者 杨新林 黄文强 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第3期303-309,共7页
Monodisperse poly(poly(ethyleneglycol) methyl ether acrylate-co-acrylic acid) (poly(PEGMA-co-AA)) microspheres were prepared by distillation-precipitation polymerization with divinylbenzene (DVB) as crosslin... Monodisperse poly(poly(ethyleneglycol) methyl ether acrylate-co-acrylic acid) (poly(PEGMA-co-AA)) microspheres were prepared by distillation-precipitation polymerization with divinylbenzene (DVB) as crosslinker with 2,2'- azobisisobutyronitrile (AIBN) as initiator in neat acetonitrile without stirring. Under various reaction conditions, four distinct morphologies including the sol, microemulsion, microgels and microspheres were formed during the distillation of the solvent from the reaction system. A 2D morphological map was established as a function of crosslinker concentration and the polar monomer AA concentration, in comonomer feed in the transition between the morphology domains. The effect of the covalent crosslinker DVB on the morphology of the polymer network was investigated in detail at AA fraction of 40 vol%. The ratios of acid to ethylene oxide units presenting in the comonomers dramatically affected the polymer-polymer interaction and hence the morphology of the resultant polymer network. The covalent crosslinking by DVB and the hydrogen bonding crosslinking between two acid units as well as between the acid and ethylene oxide unit played key roles in the formation of monodisperse polymer microspheres. 展开更多
关键词 Distillation-precipitation polymerization Monodisperse microspheres DIVINYLBENZENE poly(ethyleneglycol) methyl ether acrylate Acrylic acid Hydrogen bonding.
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Fabrication of Microspheres Based on Poly(4-butyltriphenylamine) Blends with Poly(methyl methacrylate) and Block Copolymer by Solvent Evaporation Method 被引量:1
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作者 Hossein Taherzadeh Kenji Ogino 《Open Journal of Organic Polymer Materials》 2015年第2期37-42,共6页
Micron-sized polymer particles from single poly(4-butyltriphenylamine) (PBTPA) homopolymer, binary polymer blend [PBTPA/poly(methyl methacrylate) (PMMA)], and ternary polymer blend (PBTPA/PBTPA-b-PMMA/PMMA) via a solv... Micron-sized polymer particles from single poly(4-butyltriphenylamine) (PBTPA) homopolymer, binary polymer blend [PBTPA/poly(methyl methacrylate) (PMMA)], and ternary polymer blend (PBTPA/PBTPA-b-PMMA/PMMA) via a solvent evaporation method, and the surface morphologies and inside structure of resulting particles were investigated. Spherical homopolymer particles with smooth surface were resulted from PBTPA with low molecular weight. In the case of binary blends (PBTPA/PMMA = 1/1), Janus (low molecular weight) and dumbbell (high molecular weight) type morphologies were observed. The particles based on ternary blends containing PBTPA-b-PMMA showed core-shell type morphologies (PMMA;core, PBTPA;shell). Degree of engulfment of PMMArich domain increased with the content of the block copolymer. The decrease of domain size was not observed although the block copolymer had a suitable structure as a compatibilizer for the blend. It was also found that the initial concentration of polymer solution had an effect on the final morphology. 展开更多
关键词 microspherE Morphology polymer Blend Block Copolymer poly(4-butyltriphenylamine)
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RING-OPENING COPOLYMERIZATION OF DL-LACTIDE AND POLY(ETHYLENE GLYCOL) INITIATED BY LANTHANUM ACETATE AND APPLICATION OF THE COPOLYMER AS MATRIX OF MICROSPHERES CONTAINING VIBRIO CHOLERA ANTIGENS 被引量:1
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作者 Xian-mo Deng Xiao-hong Li +4 位作者 Ming-long Yuan Xiong-wei Li Cheng-dong Xiong Zhi-tang Huang Wen-xiang Jia Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu, 610041, China Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100080, China West China University of Medical Sciences, Chengdu, 610041, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第3期265-270,共6页
Poly-dl-lactide-poly(ethylene glycol) (PELA) triblock copolymers were synthesized with lanthanum acetate as the initiator. PELA microspheres with entrapped Vibrio Cholera antigen and outer membrane protein (OMP) were ... Poly-dl-lactide-poly(ethylene glycol) (PELA) triblock copolymers were synthesized with lanthanum acetate as the initiator. PELA microspheres with entrapped Vibrio Cholera antigen and outer membrane protein (OMP) were prepared by a double emulsion W/O/W based on solvent extraction methods. The obtained microspheres showed smooth and spherical surface and their size varied between 0.5 and 5.0 mu m, which are suitable for oral targeting delivery system. The distribution tests in rabbits and mice through scanning electronic micrography and fluorescence microscope indicated that microspheres have successfully reached the immunization-related tissues, such as the liver, spleen and intestinal peyer's patches, following oral administration. The PELA microspheres were also evaluated as an efficient antigen delivery system by enhancing a higher protective ratio against live Vibrios Cholera. 展开更多
关键词 poly-dl-lactide-poly(ethylene glycol) Vibrio Cholera antigen lanthanum acetate microsphere protective ratio
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Preparation and Characterization of Titania-grafted Poly(styrene-divinybenzene) Nanocomposite Microspheres
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作者 LI Sen CHENG Jiang +1 位作者 WANG Kuan YANG Zhuo-ru 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第3期378-382,共5页
Titania-grafted poly(styrene-divinylbenzene)(TiO2/PSt-DVB) nanocomposite microspheres were prepared by an open-ring reaction and radical grafting copolymerization method. The TiO2 nanoparticles were first modified... Titania-grafted poly(styrene-divinylbenzene)(TiO2/PSt-DVB) nanocomposite microspheres were prepared by an open-ring reaction and radical grafting copolymerization method. The TiO2 nanoparticles were first modified by attachment of epoxy groups to their surfaces to provide reactive groups that could covalently bond to the polymer (PSt-DVB) microspheres. The nanocomposite obtained was characterized by FTIR, SEM, XRD, and TGA analyses as well as UV-Vis spectrophotometry. The results indicated that the TiO2 nanoparticles were uniformly grafted onto the surface of the polymer microsphere producing grain sizes of about 5―10 μm. The modified TiO2 showed better UV absorbing property than the unmodified form, and the nanocomposite also retained the same UV absorbing property as the free modified TiO2 nanoparticle. 展开更多
关键词 Titania-grafted poly(styrene-divinylbenzene) NANOCOMPOSITE microspherE
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Effects of poly lactic-co-glycolic acid-Nogo A antibody delayed-release microspheres on regeneration of injured spinal cord in rats
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作者 Hai Lan Yueming Song 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第5期358-364,共7页
BACKGROUND: Nogo A antigen is the major inhibiting factor blocking regeneration of the injured spinal cord. Neutralizing Nogo A antigens using Nogo A antibodies may help promote neurite regeneration and nervous funct... BACKGROUND: Nogo A antigen is the major inhibiting factor blocking regeneration of the injured spinal cord. Neutralizing Nogo A antigens using Nogo A antibodies may help promote neurite regeneration and nervous function recovery. For successful regeneration, sustained release of the antibody from a biodegradable material loaded with Nogo A antibodies to the injury site is required. OBJECTIVE: To compare the therapeutic effects of poly lactic-co-glycolic acid (PLGA)-Nogo A antibody delayed-release microspheres and Nogo A antibody alone on spinal regeneration in Sprague-Dawley rats with complete transverse injury to the spinal cord. DESIGN, TIME AND SETTING: A randomized, controlled animal trial was performed at the Pharmacological Laboratory of West China Center of Medical Sciences, Sichuan University, between October 2007 and January 2008. MATERIALS: Goat anti-rat Nogo A monoclonal antibody was purchased from Santa, American; goat anti-rat neurofilament 200 monoclonal antibody was from Zhongshan Goldenbridge, Beijing, China; PLGA-Nogo A antibody delayed-release microspheres were provided by the College of Pharmacy, Sichuan University. METHODS: A total of 36 adult female Sprague Dawley rats were used to establish models of completely transected spinal cord injury, at T10. Animals were randomly divided into three groups (n=12): model, Nogo A antibody alone, and Nogo A antibody delayed-release microsphere groups. After transverse injury of the spinal cord, 50 μ L normal saline solution, 50 μL normal saline solution containing 50μL g Nogo A antibody, and 50 μL normal saline solution containing 50 μg Nogo A antibody microspheres were administered to the respective groups at the injury site. MAIN OUTCOME MEASURES: The expression of Nogo A and neurofilament 200 in injured spinal cord was tested immunohistochemically, and motor function of rats was assessed by Basso-Beattie-Bresnahan (BBB) locomotor rating scale. RESULTS: Four weeks after injury, expression of Nogo A in microsphere group was significantly less than model and Nogo A antibody alone groups (P 〈 0.05); while there was no significant difference between model and Nogo A antibody alone groups (P 〉 0.05). Ten weeks after injury, microsphere group showed a significantly greater expression of neurofilament 200 than model and Nogo A antibody alone groups (P 〈 0.05); while no significant difference was found between model and Nogo A antibody alone groups (P 〉 0.05). At postoperative weeks 5 and 6, the score of BBB locomotor rating scale in microsphere group was significantly greater than the model group (P 〈 0.05), and at postoperative weeks 7 10, the score was much greater than model and Nogo A antibody alone groups (P 〈 0.05). CONCLUSION: Nogo A antibody delayed-release microspheres decreased Nogo A expression, increased neurofilament 200 expression in the injured spinal cord of rats, and promoted recovery of motor function through sustained drug release over a long-term period. 展开更多
关键词 Nogo A antibody microspheres poly lactic-co-glycolic acid spinal cord injury neural regeneration
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Synthesis and Characterization of Poly(L-lactide-co-glycolide)
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作者 刘丽莉 蔡伟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第B12期217-219,共3页
Poly ( l- lactide- co-glycolide ) ( PLGA ) with different compositions was prepared using stannous octaoate as catalyst by bulk ring-opening copolymerization of l-lactide and glycolide. The structure and properti... Poly ( l- lactide- co-glycolide ) ( PLGA ) with different compositions was prepared using stannous octaoate as catalyst by bulk ring-opening copolymerization of l-lactide and glycolide. The structure and properties of the PLGA copolymers were cbaracterized by means of attenuated total reflectance-Fourier transform infrared (ATR-FTIR), ^1H NMR, differential scanning calorimeter ( DSC and X-ray diffraction (XRD) methods, The experimented results indicate that the synthetic conditions and the composition of copolymers have art obvious influence on the structure of PLGA copolymers, The degradation rate of eopolymers increased with the increasing of the glycolide component in the copolymers. 展开更多
关键词 poly l- lactide-co-glycolide COpolyMERS degradation biodegradable
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pH-Compensation Effect of Lysine on the Acidic Degradation of Electrospun Poly( lactide-co-glycolide) Fibers in PBS
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作者 杨亮亮 王先流 +2 位作者 谢静 娄向新 张彦中 《Journal of Donghua University(English Edition)》 EI CAS 2014年第4期525-529,共5页
Electrospun aligned ultrafine fibers of poly( lactide-coglycolide)( PLGA) can be used to construct biomimetic scaffolds for engineering those structurally anisotropic and dense tissues( e. g.,tendon,ligament,etc.). Bu... Electrospun aligned ultrafine fibers of poly( lactide-coglycolide)( PLGA) can be used to construct biomimetic scaffolds for engineering those structurally anisotropic and dense tissues( e. g.,tendon,ligament,etc.). But the acidic degradation products of the PLGA could result in p H decrease in the vicinity of the scaffolds,which may give rise to biocompatibility concerns. To address the noted problem, this study was designed to evaluate the p Hcompensation capacity of using Lysine( Lys) —a kind of basic amino acid on the acidic degradation products of PLGA. Ultrafine PLGA( 50∶ 50) fibers with 0,10%,20%,and 30% by weight of Lys loadings were prepared by a stable jet electrospinning( SJES)approach. The morphology,structure,and mechanical properties of the electrospun aligned fibrous mats of Lys-incorporated PLGA( 50∶50) were characterized by scanning electron microscope( SEM),Fourier transform infrared spectroscopy( FTIR),and tensile testing,respectively. Thereafter,the fibrous PLGA( 50 ∶50) scaffolds were subjected to degradation by being immersed in phosphate buffered saline( PBS,p H 6. 86) solution at 37 ℃ for 5weeks. Our results show that the formed Lys / PLGA composite ultrafine fibers have a well-aligned and uniform morphology with a fineness of ca. 1 #m in diameter. Introduction of Lys led to increased mechanical performance; that is,when the Lys loading is less than 30%,tensile strength and Young's modulus of the aligned Lys / PLGA fibers reached up to the impressive values of 84. 5 MPa and 2. 4 GPa,respectively. Degradation results show that the p H of the PLGA group fell to 5. 6 in 5 weeks while the p H of the Lys /PLGA groups with 10%,20%, and 30% of Lys loadings was maintained at 6. 3, 6. 5 and 6. 7, respectively. This work demonstrated that incorporation of Lys into electrospun PLGA fibers could be an effective approach in mediating the p H decrease caused by the acidic degradation products of the PLGA. 展开更多
关键词 poly(lactide-co-glycolide)(PLG A) LYSINE pH compensation DEGRADATION electrospinning
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Synthesis and Physicochemical Characterization of Biodegradable Star-Shaped Poly Lactide-Co-Glycolide-<i>β</i>-Cyclodextrin Copolymer Nanoparticles Containing Albumin
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作者 Soodabeh Davaran Akbar Rezaei +4 位作者 Somayeh Alimohammadi Amir Ahmad Khandaghi Kazem Nejati-Koshki Hamid Tayefi Nasrabadi Abolfazl Akbarzadeh 《Advances in Nanoparticles》 2014年第1期14-22,共9页
The purposes of this research were to synthesize and characterize star-shaped poly lactide-co-glycolide-β-cyclo-dextrin (PLGA-β-CD) copolymer by reacting L-lactide, glycolide and β-cyclodextrin in the presence of s... The purposes of this research were to synthesize and characterize star-shaped poly lactide-co-glycolide-β-cyclo-dextrin (PLGA-β-CD) copolymer by reacting L-lactide, glycolide and β-cyclodextrin in the presence of stannous octoate as a catalyst. The structure of PLGA-β-CD copolymer was confirmed with 1H-NMR, 13C-NMR and FT-IR spectra. Albumin as a model peptide drug was encapsulated within nanoparticles made of PLGA-β-CD with a modified double emulsion method. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) photomicrographs showed that the nanoparticles have the mean diameter within the range of 80 - 210 nm. Also they were almost spherical in shape. Effects of the experimental parameters, such as copolymer composition, copolymer concentration, and reaction temperature, on particular size and encapsulation efficiency were investigated. 展开更多
关键词 ALBUMIN STAR-SHAPED poly lactide-co-glycolide β-Cyclodextrin Nanoparticles
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INVESTIGATION OF POLYDL-LACTIDE-b-POLY(ETHYLENE GLYCOL)-b-POLYDL-LACTIDE MICROSPHERES CONTAINING PLASMID DNA
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作者 刘鈺 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2004年第3期205-214,共10页
PolyDL-lactide (PDLLA) and the block copolymer, polyDL-lactide-b-poly(ethylene glycol)-b-polyDL-lactide (PELA) were used as the microsphere matrix to encapsulate plasmid DNA. The PDLLA, PELA, pBR322-loaded PDLLA and p... PolyDL-lactide (PDLLA) and the block copolymer, polyDL-lactide-b-poly(ethylene glycol)-b-polyDL-lactide (PELA) were used as the microsphere matrix to encapsulate plasmid DNA. The PDLLA, PELA, pBR322-loaded PDLLA and pBR322-loaded PELA microspheres were prepared by solvent extraction method based on the formation of multiple w1/o/w2 emulsion. The microspheres were characterized by surface morphology, mean particle size, particle size distribution and loading efficiency. The integrity of DNA molecules after being extracted from microspheres was determined by agarose gel electrophoresis. The result suggested that plasmid DNA molecules could retain their integrity after being encapsulated by PELA. The PELA microspheres could prevent plasmid DNA from being digested by DNase. The in vitro degradation and release profiles of plasmid DNA-loaded microspheres were measured in pH = 7.4 buffer solution at 37 °C. The in vitro degradation profiles of the microspheres were evaluated by the deterioration in microspheres surface morphology, the molecular weight reduction of polymer, the mass loss of microspheres, the changes of pH values of degradation medium, and the changes of particle size. The in vitro release profiles of the microspheres were assessed by measurement of the amount of DNA presented in the release medium at determined intervals. The release profiles were correlation with the degradation profiles. The release of plasmid DNA from PELA microspheres showed a similar biphasic trend, that is, an initial burst release was followed by a slow, but sustained release. 展开更多
关键词 polyDL-lactide-b-poly(ethylene glycol)-b-polyDL-lactide (PELA) microspheres pBR322 DNA Degradation RELEASE
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Effect of the implant composite of poly lactide-co-glycolide and bone mesenchymal stem cells modified by basic fibroblast growth factor on injured spinal cord in rats
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作者 刘文革 《外科研究与新技术》 2011年第2期130-130,共1页
Objective To investigate the effect of the implant composite of poly lactide-co-glycolide(PLGA)and bone mesenchymal stem cells (BMSCs) modified by basic fibroblast growth factor (bFGF) on injured spinal cord in rats.M... Objective To investigate the effect of the implant composite of poly lactide-co-glycolide(PLGA)and bone mesenchymal stem cells (BMSCs) modified by basic fibroblast growth factor (bFGF) on injured spinal cord in rats.Methods Two hundred and 展开更多
关键词 BMSCs bFGF Effect of the implant composite of poly lactide-co-glycolide and bone mesenchymal stem cells modified by basic fibroblast growth factor on injured spinal cord in rats stem
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Preparation of Tolterodine Metabolite Loaded Biodegradable PLGA Microspheres 被引量:8
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作者 TENG Le-sheng JIANG Chao-jun LIN Xiang-you DONG Yuan-chen LI Chun-mei MENG Qing-fan LI You-xin 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第1期75-80,共6页
Biodegradable polymer poly(lactic-co-glycolic acid)(PLGA) was used to encapsulate the pharmacological activity metabolite of tolterodine by means of O/W emulsion solvent evaporation method via homogenization in th... Biodegradable polymer poly(lactic-co-glycolic acid)(PLGA) was used to encapsulate the pharmacological activity metabolite of tolterodine by means of O/W emulsion solvent evaporation method via homogenization in the emulsification process. The influences of preparation parameters were investigated. The results indicate that increa- sing PLGA concentration from 15% to 40% made the encapsulation efficiency of 5-hydroxymethyl derivative of tol- terodine(5-HMT) increased from 55.39% to 76.32%, and the particle size increased from 34.33 μm to 70,78 lain. In addition, when homogenization speed increased from 850 r/min to 2300 r/min, both particle size and encapsulation efficiency of microspheres decreased. An increase in the volume of aqueous phase led to higher encapsulation efficiency and bigger particle size. Increasing temperature made encapsulation efficiency and particle size change significantly. While reaction temperature increased from 20 ℃ to 50 ℃, the encapsulation efficiency decreased from 70.44% to 24.07%, and particle size increased from 38.66 μm to 69.38 μm. High reaction temperature(over 40 ℃) may lead to porous surface of microspheres. Porous surface, encapsulation efficiency and particle size influenced on the in vitro release of 5-HMT together. 展开更多
关键词 poly(lactic-co-glycolic acid) microspherE TOLTERODINE Tolterodine metabolite
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A combination of chondroitinase ABC,glial cell line-derived neurotrophic factor,and Nogo A antibody delayed-release microspheres for the treatment of spinal cord injury
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作者 Yu Zhang Yueming Song 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第10期772-777,共6页
The purpose of this study was to evaluate the effect of poly(lactide-co-glycolic acid) delayed-release microspheres,which were prepared using glial cell line-derived neurotrophic factor(GDNF),on the delayed-releas... The purpose of this study was to evaluate the effect of poly(lactide-co-glycolic acid) delayed-release microspheres,which were prepared using glial cell line-derived neurotrophic factor(GDNF),on the delayed-release,controllability,and protection of GDNF activity.The present study is the first to combine chondroitinase ABC,GDNF,and Nogo A antibody delayed-release microspheres for the treatment of spinal cord injury.Results show that the combined therapy of chondroitinase ABC,GDNF,and Nogo A antibody microspheres can increase the immunoreaction of neurofilament 200 in the injured spinal cord,and this therapeutic effect was better than chondroitinase ABC,GDNF,or Nogo A antibody microspheres administered singularly. 展开更多
关键词 glial cell line-derived neurotrophic factor microspheres poly(lactide-co-glycolic acid) spinal cord injury neural regeneration
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Effect of Excipients on Stability and Structure of rhCuZn-SOD Encapsulated in PLGA Microspheres
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作者 LIU Ling 1,2 ,GE Yu 1 and YUAN Qin-sheng 1 1. State Key Laboratory of Bioreactor Engineering and Institute of Biochemistry,East China University of Science and Technology,Shanghai 200237,P. R. China 2. Public Health School,Nanjing Medical University,Nanjing 210029,P. R. China 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第3期323-327,共5页
When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic... When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic solvent and a polymer may cause the denaturation of the protein. In this study,we investigated the enzymatic activity change and the effect of the excipients on the stability of recombinant human Cu,Zn-superoxide dismutase(rhCu,Zn-SOD) during the emulsification. The specific activity recovery was found to be concentration dependent and the excipients involved such as PEG 600 and Tween 20,and trehalose were shown to increase the stability of rhCu,Zn-SOD. The protein structural integrity within the microspheres was analyzed by FTIR. The structure of rhCu,Zn-SOD within PLGA microspheres containing trehalose was found to be similar to that of the native solid state,whereas the protein encapsulated during the preparation in the absence of any excipient changed due to the possible hydrophobic interaction with the polymer. The results suggest that a rational stability strategy for protein to be encapsulated into microspheres should aim at different processes. 展开更多
关键词 poly( DL -lactide-co-glycolide)(PLGA) microsphere Recombinant human Cu Zn-superoxide dismutase(rhCu Zn-SOD) Fourier transform infrared(FTIR) spectroscopy Protein stability EXCIPIENT
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Dexamethasone-Loaded PLGA Microspheres Incorporated PLLA/PLGA/PCL Composite Scaffold for Bone Tissue Engineering
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作者 苗莹珂 聂伟 +2 位作者 王伟忠 周小军 何创龙 《Journal of Donghua University(English Edition)》 EI CAS 2017年第1期159-163,共5页
The combination of micro-carriers and polymer scaffolds as promising bone grafts have attracted considerable interest in recent decades.The poly(L-lactic acid)/poly(lactic-co-glycolic acid)/polycaprolactone(PLLA/PLGA/... The combination of micro-carriers and polymer scaffolds as promising bone grafts have attracted considerable interest in recent decades.The poly(L-lactic acid)/poly(lactic-co-glycolic acid)/polycaprolactone(PLLA/PLGA/PCL)composite scaffold with porous structure was fabricated by thermally induced phase separation(TIPS).Dexamethasone(DEX)was incorporated into PLGA microspheres and then loaded on the PLLA/PLGA/PCL scaffoldtopreparethedesiredcompositescaffold.The physicochemical properties of the prepared composite scaffold were characterized.The morphology of rat bone marrow mesenchymal stem cells(BMSCs)grown on scaffolds was observed using scanning electron microscope(SEM)and fluorescence microscope.The resultsshowedthatthePLLA/PLGA/PCLscaffoldhad interconnected macropores and biomimetic nanofibrous structure.In addition,DEX can be released from scaffold in a sustained manner.More importantly,DEX loaded composite scaffold can effectively support the proliferation of BMSCs as indicated by fluorescence observation and cell proliferation assay.The results suggested that the prepared PLLA/PLGA/PCL composite scaffold incorporating drug-loaded PLGA microspheres could hold great potential for bone tissue engineering applications. 展开更多
关键词 composite scaffold poly(lactic-co-glycolic acid)(PLG A) microsphere DEXAMETHASONE bone tissue engineering
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运载双层抗原蛋白的CS-PLGA制剂制备及其表征鉴定
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作者 郑蕊 杨晓岚 +1 位作者 王慧 罗德炎 《安徽医科大学学报》 CAS 北大核心 2024年第7期1213-1218,共6页
目的制备运载双层抗原的CS-PLGA微球制剂,并对其进行相关表征鉴定。方法通过复乳法结合溶剂挥发法制备得到多孔微球后,在4℃水浴条件下装载抗原,利用抗原浓度梯度介导的物理扩散促进抗原进入微球内部,并通过静电作用结合在微球外表面,... 目的制备运载双层抗原的CS-PLGA微球制剂,并对其进行相关表征鉴定。方法通过复乳法结合溶剂挥发法制备得到多孔微球后,在4℃水浴条件下装载抗原,利用抗原浓度梯度介导的物理扩散促进抗原进入微球内部,并通过静电作用结合在微球外表面,形成内外双层抗原运载。根据聚乳酸-羟基乙酸共聚物(PLGA)材料玻璃转化温度这一特性,促进多孔微球表面孔道在48℃条件下发生愈合,使其形成闭合的微球制剂,再将得到的微球制剂与壳聚糖溶液混悬镀层,进行阳离子修饰,逆转微球表面负性电位。通过扫描电子显微镜、动态光散射粒度仪等检测微球形态、粒径分布和电位变化,采用十二烷基硫酸钠聚丙烯酰胺凝胶电泳(SDS-PAGE)鉴定抗原是否装载至微球制剂中,采用荧光标记的BSA和荧光标记的PLGA材料进行激光共聚焦显微镜观察抗原装载后的分布情况,通过BCA法检测微球制剂的包封率和载药率。结果扫描电镜和光学显微镜结果显示多孔微球成孔良好,粒径大小为(73.94±0.81)nm,多分散性指数为0.038±0.004。Zeta电位由负转正说明壳聚糖已被成功镀层至微球表面。经过SDS-PAGE、激光共聚焦显微镜等证实BSA已被成功运载。经micro BCA试剂盒检测后多孔微球包封率为(3.01±0.04)%,载药率为(1.50±0.02)%。结论成功制备得到运载双层抗原的CS-PLGA制剂,为后续缓控释制剂研究提供新思路。 展开更多
关键词 聚乳酸-羟基乙酸共聚物 壳聚糖 多孔微球 抗原装载 自愈合
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万古霉素缓释微球的制备及其质量评价
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作者 宋远征 叶演 +4 位作者 巩守超 张玉东 刘志 孙红武 曾浩 《国际医药卫生导报》 2024年第14期2413-2418,共6页
目的制备质量稳定、安全有效的载万古霉素缓释微球,评价其质量特征。方法采用复乳溶剂挥发法将聚乳酸(polylactic acid,PLA)和聚乳酸-羟基乙酸共聚物[poly(lactic-co-glycolic acid),PLGA]按3种不同比例混合制备万古霉素微球进行筛选;... 目的制备质量稳定、安全有效的载万古霉素缓释微球,评价其质量特征。方法采用复乳溶剂挥发法将聚乳酸(polylactic acid,PLA)和聚乳酸-羟基乙酸共聚物[poly(lactic-co-glycolic acid),PLGA]按3种不同比例混合制备万古霉素微球进行筛选;利用单因素实验,研究不同浓度聚乙烯醇(polyvinyl alcohol,PVA)、内外水相比例对微球粒径、包封率、载药量的影响后并制备出优选的载万古霉素的PLA/PLGA缓释微球;对其体内外抗多重耐药菌耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus,MRSA)进行药效学研究。采用单因素方差分析。结果内外水相比和PVA浓度对万古霉素的包封率和载药量影响不大(P>0.05),但微球中PLA和PLGA质量比对万古霉素的包封率和载药量差异有统计学意义(P<0.0001),纯PLA时微球平均粒径[(41.95μm)]、包封率[(28.87±0.32)%]和载药量[(17.80±0.21)%]最大。万古霉素微球对MRSA 252的抗菌活性高于其水溶液(最小抑菌浓度0.391 ng/L比0.781 ng/L)(P<0.0001)。万古霉素微球治疗受损皮肤感染MRSA 252比相同浓度的万古霉素水溶液具有更满意的杀菌活性(P<0.05)。万古霉素微球对感染MRSA 252小鼠的伤口治愈效果比万古霉素水溶液更好。结论通过优选获得的微球处方,制备的PLA/PLGA缓释微球可实现万古霉素药物的局部可控释放,通过调节PLA和PLGA在共混物中的比例提高药物包封率和载药量、定制降解速率、改变药物释放,是有效对抗金黄色葡萄球菌感染的制剂。 展开更多
关键词 聚乳酸 聚乳酸-羟基乙酸共聚物 万古霉素 缓释微球 耐甲氧西林金黄色葡萄球菌
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聚对苯乙烯磺酸微球的绿色制备及催化合成生物柴油 被引量:1
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作者 张春燕 苏佳俊 +3 位作者 尹惠 姚晨曦 肖俊 罗建新 《精细化工》 EI CAS CSCD 北大核心 2023年第5期1065-1072,共8页
以水为介质、苯乙烯(St)为基体单体、二乙烯苯(DVB)为交联单体、对苯乙烯磺酸钠(Na SS)为功能单体、甲基丙烯酸(MAA)为水溶性单体、过硫酸钾(KPS)为引发剂,采用无皂乳液聚合法制备了聚对苯乙烯磺酸微球(PSS)。利用FTIR、XPS、SEM、TGA和... 以水为介质、苯乙烯(St)为基体单体、二乙烯苯(DVB)为交联单体、对苯乙烯磺酸钠(Na SS)为功能单体、甲基丙烯酸(MAA)为水溶性单体、过硫酸钾(KPS)为引发剂,采用无皂乳液聚合法制备了聚对苯乙烯磺酸微球(PSS)。利用FTIR、XPS、SEM、TGA和DSC对其进行了表征,并对其粒径、Zeta电位、比表面积、酸密度进行了考察,探讨了Na SS、DVB和KPS用量对PSS结构、性能的影响。当H_(2)O为90m L、St为76.9 mmol、MAA为9.3 mmol、NaSS为0.7mmol、DVB为7.7 mmol、KPS为0.7mmol时,制备的PSS-3粒径均匀且酸密度较高。然后,将PSS-3作为固体酸催化剂,用于催化油酸/甲醇酯化合成生物柴油(油酸甲酯)。结果表明,当甲醇/油酸的物质的量比为10∶1、PSS-3用量为油酸质量的2%、反应温度为80℃、反应时间为6h时,油酸的转化率可达86.4%。PSS-3作为固体酸催化剂具有较好的重复使用性能,循环使用4次后油酸转化率没有明显下降。 展开更多
关键词 无皂乳液聚合 聚对苯乙烯磺酸微球 生物柴油 油酸 催化技术
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载Apelin-13缓释微囊的新型生物支架促兔输卵管再通的初步研究
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作者 赵群 薛敏 +3 位作者 李俞延 郑义凡 徐哲伟 李志跃 《中南大学学报(医学版)》 CAS CSCD 北大核心 2023年第9期1304-1315,共12页
目的:输卵管炎性不孕症严重危害女性自然生育功能,临床迫切需求的真正意义上的输卵管再通包括病变输卵管解剖和功能的修复两方面,目前尚无有效的治疗方案。本研究旨在从这两方面探讨促进输卵管修复再通的方法。方法:制备Apelin-13缓释... 目的:输卵管炎性不孕症严重危害女性自然生育功能,临床迫切需求的真正意义上的输卵管再通包括病变输卵管解剖和功能的修复两方面,目前尚无有效的治疗方案。本研究旨在从这两方面探讨促进输卵管修复再通的方法。方法:制备Apelin-13缓释微囊和聚乳酸-羟基乙酸共聚物[poly(lactic-co-glycolic acid),PLGA]三维生物支架,检测生物支架的基本特性及体内降解情况(质量损失率),微囊的体外释药(累积释药率)、体内释药(Apelin-13血药浓度)及体外降解(降解率)情况。将Apelin-13微囊(微囊组)/载Apelin-13缓释微囊的PLGA三维生物支架(支架微囊组)注入/置入慢性输卵管炎新西兰兔模型的输卵管,观察和比较对照组、模型组、微囊组和支架微囊组术后输卵管的通畅情况、镜下结构、雌激素受体和孕激素受体的阳性表达情况。结果:术后第4周时PLGA三维生物支架的质量损失率为98.66%,微囊的体外降解率为70.58%,Apelin-13缓释微囊30 d体外累计释药率达98.68%,Apelin-13血药浓度在5 d内达到峰值,并在25 d内保持稳定。与模型组和微囊组相比,支架微囊组术后输卵管管腔内炎症反应轻,输卵管通畅率高,雌激素受体和孕激素受体的表达水平高(均P<0.05),支架微囊组的各项指标接近对照组。结论:载Apelin-13缓释微囊的PLGA三维生物支架可全面修复输卵管的解剖结构和生理功能,有望真正有效实现炎性输卵管再通。 展开更多
关键词 输卵管再通 聚乳酸-羟基乙酸共聚物 APELIN-13 三维生物支架 缓释微囊
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