口服聚酯聚醚疫苗蛋白微球的制备研究

采用本体聚合法合成不同聚醚含量的聚酯聚醚嵌段共聚物聚 ＤＬ 乳酸 聚乙二醇（Ｐｏｌｙ ＤＬ ｌａｃｔｉｄｅ ｂ ｐｏｌｙｅｔｈｙｌｅｎｅｇｌｙｃｏｌ,ＰＥＬＡ）．ＰＥＬＡ及ＰＬＡ包裹人血清白蛋白（ＨＳＡ）微球采用溶剂挥发法双乳液体系（Ｗ１／Ｏ／Ｗ２）制备．微球球形规整,粒径集中在０５～５０μｍ．用ＣＢＢ法检测微球中蛋白含量,蛋白包裹量达２５％,包裹效率近８０％．从双乳液体系中界面张力角度考察了聚合物囊材的性质、稳定剂的种类及Ｗ１／Ｏ的稳定性等对微球粒径及蛋白包裹量的影响．微球体外释放结果表明ＰＥＬＡ蛋白微球的突释现象不明显,释放速度较为恒定．     

可生物降解聚合物乙肝疫苗微球的制备和表征

采用双乳液体系（Ｗ１／Ｏ／Ｗ２）溶剂抽提法制备了聚－ＤＬ－乳酸－聚乙二醇嵌段共聚物（Ｐｏｌｙ－ｄｌｌａｃｔｉｄｅ－ｂ－ｐｏｌｙｅｔｈｙｌｅｎｅ ｇｌｙｃｏｌ,ＰＥＬＡ）包裹乙肝表面抗原（ＨＢｓＡｇ）微球。微球外观规整,平均粒径２．１７μｍ,抗原包裹量达１．２５％,包裹效率７１．８％。经聚丙烯酰胺凝胶电泳（ＰＡＧＥ）检测,ＨＢｓＡｇ在微球制备过程中保持了结构完整性。以乙肝常规铝佐剂疫苗为对照,ＢＡＬ     

可生物降解的聚乳酸弹性体的合成与表征

本文将丙交酯（ＤＬ－ＬＡ）与聚乙二醇（ＰＥＧ）的预聚体用甲苯－二异氰酸酯８０（ＴＤＩ）扩链，得到了一系列的聚乳酸（聚醚）型聚氨酯（ＰＥＧ－ＰＬＡ／ＰＵ）弹性体。对预聚体和弹性体分别进行了ＩＲ、ＨＮＭＲ和ＤＭＡ表征，并测定了弹性体的力学性能。结果表明，ＬＡ与ＰＥＧ生成的预聚体是一种三嵌段结构：ＨＯ－ＰＬＡ－ＰＥＧ－ＰＬＡ－ＯＨ。随着ＰＥＧ含量的增加，弹性体的玻璃化温度下降；ＰＥＧ分子量增大时，弹性体     

SELECTIVE HYDROGENATION OF 2－NAPHTHOL CATALYZED BYA SILIC A－SUPPORTED POLYALUMAZANE PLATINUM COMPLES

ＳＥＬＥＣＴＩＶＥＨＹＤＲＯＧＥＮＡＴＩＯＮＯＦ２－ＮＡＰＨＴＨＯＬＣＡＴＡＬＹＺＥＤＢＹＡＳＩＬＩＣＡ－ＳＵＰＰＯＲＴＥＤＰＯＬＹＡＬＵＭＡＺＡＮＥＰＬＡＴＩＮＵＭＣＯＭＰＬＥＳＣｈｕｎＷｅｉＣＨＥＮ；ＪｉＷｅｎＺＨＥＮＧ；ＭｅｉＹｕＨＵＡＮＧａｎ...     

KINETIC MODEL LING OF COMPLEX REACTIONS BASED ON EL EMENTARY STEPS

ＫＩＮＥＴＩＣＭＯＤＥＬＬＩＮＧＯＦＣＯＭＰＬＥＸＲＥＡＣＴＩＯＮＳＢＡＳＥＤＯＮＥＬＥＭＥＮＴＡＲＹＳＴＥＰＳＣｈｅｎＱｉ（ＫｉｎｅｔｉｃｓＴｅｃｈｎｏｌｏｇｙＩｎｔｅｒｎａｔｉｏｎａｌＢ．Ｖ．，Ｐ．Ｏ．Ｂｏｘ８６，２７００ＡＢＺｏｅｔｅｒｍｅｅｒ...     

STUDIES ON THE SYNTHESIS OF SESAMIN－GROUP LIGNANS V． A CONVENIENT METHOD FOR THE PREPARATION OF 2－ARYL－4－PHENYLOXAZOLES

ＳＴＵＤＩＥＳＯＮＴＨＥＳＹＮＴＨＥＳＩＳＯＦＳＥＳＡＭＩＮ－ＧＲＯＵＰＬＩＧＮＡＮＳＶ．ＡＣＯＮＶＥＮＩＥＮＴＭＥＴＨＯＤＦＯＲＴＨＥＰＲＥＰＡＲＡＴＩＯＮＯＦ２－ＡＲＹＬ－４－ＰＨＥＮＹＬＯＸＡＺＯＬＥＳ￥Ｃｏｒｒｅｓｐｏｎｄｅｎｔａｕｔｈｏｒ．２－ａｒｙｌ－４－ｐｈｅｎｙｌｏｘａｚｏｌｅｓ．Ｔｈｅｏｔｈｅｒｏｌｌｅｂｙｔｈｅｒｅａｃｔｉｏｎｏｆａ－ｍｅｔｈｙｌｐｈｅｎａｃｙｌｂｅｎｚｏａｔｅｗｉｔｈａｍｍｏｎｉｕｍａｃｅｔａｔｅｉｎｂｏｉｌｉｎｇａｃｅｔｉｃａｃｉｄｔｏｆｏｒｍａｆｕｔｕｒｅｏｆ２，４－ｄｉｐｈｅｎｙｌ－５ｍｅｔｈｙｌｏｘａｚｏｌｅａｎｄ２，４－ｄｉｐｈｅｎｙｌ－５－ｒｎｅｔｈｙｌｉｎｄｄａｚｏｌｅｂｏｔｈｉｎａｂｏｕｔ４０％ｙｉｅｌｄ，ｈｉｌｔｔｉｌｌｓｍｅｔｈｏｄｉｓａｐｐｌｉｃａｂｌｅｆｏｒｔｈｅｐｒｅｐａｒａｔｉｏｎｏｆ２－ａｒｙｌ－４－ｐｈｅｎｙｌｏｘａｚｏｌｅｓ．Ｂｙａｎａｌｏｇｙ，ｐｌｉｅｎａｃｙｌｂｅｎｚｏａｔｅｉｓａｌｌｏａｌｌｏｗｅｄｔｏｒｅａｃｔｗｉｔｈａｌｎｍｏｎｉｌｌｍａｃｅｔａｔｅｉｎｂｏｉｌｉｎｇａｃｅｔｉｃａｃｉｄ．Ａｍｉｘｔｕｒｅｏｆ２，４－ｄｉｐｈ     

THE CHIRAL SELECTIVITY IN ACROSS－MEMBRANE TRANSPORT OF 1，2－DIAMINOCYCLOHEXANE PLATINUM（II）COMPLEXES AND THE CONTRIBUTION OF LEAVING GROUPS

ＴＨＥＣＨＩＲＡＬＳＥＬＥＣＴＩＶＩＴＹＩＮＡＣＲＯＳＳ－ＭＥＭＢＲＡＮＥＴＲＡＮＳＰＯＲＴＯＦ１，２－ＤＩＡＭＩＮＯＣＹＣＬＯＨＥＸＡＮＥＰＬＡＴＩＮＵＭ（ＩＩ）ＣＯＭＰＬＥＸＥＳＡＮＤＴＨＥＣＯＮＴＲＩＢＵＴＩＯＮＯＦＬＥＡＶＩＮＧＧＲＯＵＰＳ￥...     

聚乙二醇改性聚乳酸的研究

将丙交酯（ＤＬ ＬＡ）与聚乙二醇（ＰＥＧ）共聚得到了一系列高分子量的共聚物．用ＩＲ、１Ｈ ＮＭＲ和ＤＭＡ对它的结构和粘弹性进行了表征，并测定了其力学性能，同时对材料在加工过程中特征粘度的变化也进行了研究．结果表明，ＰＥＧ与ＬＡ的共聚物是一种三嵌段结构ＨＯ ＰＬＡ ＰＥＧ ＰＬＡ ＯＨ．当ＰＥＧ含量增加时，强度下降，伸长率增加，共聚物逐渐由脆性向韧性转变，因此用ＰＥＧ改性的ＰＬＡ是一种综合性能可调控的生物降解材料     

SELECTIVE HYDROGENATION OF PHENOL OVER A SILICA SUPPORTED POLYTITAZANE－Pt－Mn BIMETALLIC COMPLEX

ＳＥＬＥＣＴＩＶＥＨＹＤＲＯＧＥＮＡＴＩＯＮＯＦＰＨＥＮＯＬＯＶＥＲＡＳＩＬＩＣＡＳＵＰＰＯＲＴＥＤＰＯＬＹＴＩＴＡＺＡＮＥ－Ｐｔ－ＭｎＢＩＭＥＴＡＬＬＩＣＣＯＭＰＬＥＸ￥ｃｈｕｍＷｅｉＣＨＥＮ；ＭｅｉＹｕＨＵＡＮＧａｎｄＹｉｎｇＹａｎＪＩＡＮＧ（Ｉ...     

PARAMAGNETIC AND DIAMAGNETIC DICOPPER（Ⅱ） COMPLEXES WITH DI－SCHIFF BASE DERIVED FROM 2－HYDROXY－1－NAPHTHALDEHYDE AND1，3－DIANINO－2－PROPANOL

ＰＡＲＡＭＡＧＮＥＴＩＣＡＮＤＤＩＡＭＡＧＮＥＴＩＣＤＩＣＯＰＰＥＲ（Ⅱ）ＣＯＭＰＬＥＸＥＳＷＩＴＨＤＩ－ＳＣＨＩＦＦＢＡＳＥＤＥＲＩＶＥＤＦＲＯＭ２－ＨＹＤＲＯＸＹ－１－ＮＡＰＨＴＨＡＬＤＥＨＹＤＥＡＮＤ１，３－ＤＩＡＮＩＮＯ－２－ＰＲＯＰＡＮＯＬ...     

Preparation and characterization of biodegradable poly(l-lactide)/poly(ethylene glycol) microcapsules containing erythromycin by emulsion solvent evaporation technique

In this work, the producing of a biodegradable poly(l-lactide) (PLA)/poly(ethylene glycol) (PEG) microcapsule by emulsion solvent evaporation method was investigated. The effect of PEG segments added to the PLA microcapsules on the degradation, size distribution, and release behavior was studied. According to the results, PLA/PEG copolymer was more hydrophilic than PLA homopolymer, and with lower glass transition temperature. The surface of PLA/PEG microcapsules was not as smooth as that of PLA microcapsules, the mean diameters of prepared PLA and PLA/PEG microcapsules were 40 and 57 microm, respectively. And spherical forms were observed by the image analyzer and the scanning electron microscope (SEM). Drug release from microcapsules was affected by the properties of PLA/PEG copolymers determined by UV-vis spectra. It was found that the drug release rates of the microcapsules were significantly increased with adding of PEG, which explained by increasing hydrophilic groups.     

微米级单分散共聚物微球的制备

用分散聚合法制备了苯乙烯 甲基丙烯酸甲酯微米级单分散共聚物微球 ,粒径为 5 4 μm .将分散聚合体系与乳液聚合体系进行了比较 ,并对共聚物微球的形貌、粒径分布及共聚情况进行了表征研究 .     

PLA/PEG/PLA三嵌段共聚物载药纳米胶囊的制备及表征

用于药物控释体系的微胶束具有实心微球结构,药物分子主要吸附于微球表面,极易脱落,在释药初期有明显的突释效应;而微胶囊的药物主要集中于囊心部分,药物通过扩散作用以及高分子膜的降解而逐渐释放到环境中,因而更有利于药物分子平稳、缓慢地释放．对于自然界中能够自发形成微胶囊的小分子材料,其分子中往往具有一个较小的亲水部分和一个相对较大的憎水部分,     

Biodegradable heparin-loaded microspheres: carrier molecular composition and microsphere structure

Microspheres of amphiphilic triblock polymers PLLA-PEG-PLLA were investigated as carriers for heparin delivery. Two series of PLLA-PEG-PLLA triblock were synthesized and prepared into microspheres with heparin loaded. The microspheres were hollow and the surface morphology varied from smooth to porous. The pore size increased with increasing PEG content. The microsphere size distribution showed that higher PEG content increased the average microsphere size. The release rate of heparin was closely related to the surface morphology of the microspheres. DSC spectra showed that both cold crystalline temperature (Tc) and crystalline melting temperature (Tm) of heparin-loaded microspheres were related to the copolymer composition and the Tc was lower than those of corresponding pure microspheres. [IMAGES: SEE TEXT]     

生物可降解5-氟尿嘧啶载药微球的制备及性能研究

5-氟尿嘧啶(5-Fu)为水溶性嘧啶类抗代谢药,是治疗实体肿瘤的首选药物．但5-Fu毒性很大,血浆中停留半衰期t1／2仅为10～20min．为了减少氟尿嘧啶的毒副作用并提高药物利用率,可以将其制成聚合物载药微球．聚酯类高分子是较为常用的生物降解型药物载体材料,其中聚乳酸(PLA)及其共聚物具有良好的生物相容性及生物可降解性,常被广泛应用于药物缓释材料,     

Fabrication and enhanced mechanical properties of porous PLA/PEG copolymer reinforced with bacterial cellulose nanofibers for soft tissue engineering applications

A new class of polylactic acid (PLA)/polyethylene glycol (PEG) copolymer reinforced with bacterial cellulose nanofibers (BC) was prepared using a solvent casting and particulate leaching methods. Four weight fractions of BC (1, 2.5, 5, and 10 wt%) were incorporated into copolymer via silane coupling agent. Mechanical properties were evaluated using response surface method (RSM) to optimize the impact of pore size, porosity, and BC contents. Compressive strength obtained for PLA/PEG-5 BC wt% was 9.8 MPa, which significantly dropped after developing a porous structure to 4.9 MPa. Nielson model was applied to investigate the BC stress concentration on the PLA/PEG. Likewise, krenche and Hapli-Tasi model were employed to investigate the BC nanofiber reinforcement and BC orientation into PLA/PEG chains. The optimal parameters of the experiment results found to be 5 wt% for BC, 230 μm for pore size, and 80% for porosity. Scanning electron microscopy (SEM) micrograph indicates that uniform pore size and regular pore shape were achieved after an addition of BC-5% into PLA/PEG. The weight loss of copolymer-BC with scaffolds enhanced to the double values, compared with PLA/PEG-BC % without scaffolds. Differential Scanning Calorimetric (DSC) results revealed that the BC nanofiber improved glass transition temperature (T_g) 57 °C, melting temperature (T_m) 171 °C, and crystallinity (χ %) 43% of PLA/PEG reinforced-BC-5%.     

Chromatographic studies of mitomycin C degradation in albumin microspheres

Serum albumins and polylactic acid (PLA) have been used as bioerodable polymers in the preparation of drug-containing microspheres for parenteral drug delivery. The albumin microsphere may be prepared via either chemical cross-linking or heat denaturation of the protein. Heat-denatured albumin microspheres containing mitomycin C (MMC) have been used in pre-clinical and clinical investigations. Due to the high reactivity of MMC as a bifunctional alkylating agent, a study on the stability of MMC in the albumin and PLA microspheres has been carried out using a high-performance liquid chromatographic (HPLC) method. Human serum albumin (HSA) microspheres were prepared using an emulsion method via either heat denaturation at 120 or 170 degrees C or the use of 0.5 M biacetyl as a cross-linking agent. The PLA microspheres were prepared by an emulsion method at 55 degrees C. HPLC analysis of the HSA microspheres showed that about 37% of MMC was converted to 2,7-diaminomitosene derivatives in microspheres prepared by heat denaturation at 120 degrees C. The degradation increased to 82% when the microspheres were prepared with a denaturation temperature of 170 degrees C. The use of biacetyl as a cross-linking agent in the preparation of HSA microspheres resulted in a complete degradation of the incorporated MMC. Biacetyl was found to interact with MMC leading to the formation of 7-aminomitosene derivatives. In contrast to the albumin system, MMC may be incorporated into PLA microspheres without degradation.     

Investigation of the degradation behaviour of poly(ethylene glycol-co-d,l-lactide) copolymer

The aim was to investigate the degradation behaviour of poly(ethylene glycol-co-d,l-lactide) (PEG-d,l-PLA) multiblock copolymer, in bulk and as microspheres, in aqueous medium. The degradation behaviour of PLA homopolymers in bulk and microspheres was evaluated as comparison.Microsphere preparation was performed by the double emulsion solvent evaporation method. Physical-chemical characterization of the raw polymers and the microspheres was performed by nuclear magnetic resonance (NMR) and modulated differential scanning calorimetry (MDSC). Polymer molecular weight, before and after incubation in aqueous environment, was evaluated by GPC; water uptake and mass loss were determined gravimetrically.The presence of PEG segments inside PLA chains gave a characteristic spongy structure to the microspheres. A significant increase in polymer T_g values was found for the microsphere formulations compared to polymer in bulk. After 63 days of incubation in the aqueous environment, the PEG-d,l-PLA microspheres achieved an average M_w reduction of 47% compared to 20% for PLA microspheres. The corresponding M_w decrease of the polymers in bulk was significantly higher: 72% and 41% for PEG-d,l-PLA and PLA, respectively.The data show how the degradation behaviour of polymer in bulk in an aqueous environment is significantly different from the behaviour of the corresponding microspheres. These results highlight the importance of performing a thorough physical-chemical characterization on microsphere formulations.