N-mPEG-O-季铵化壳聚糖微球的制备及其载药性能

将聚乙二醇单甲醚（mPEG）醛化改性后,通过西佛碱反应接枝到自制的O-季铵化壳聚糖的NH2上,硼氢化钠还原制得N-mPEG接枝O-季铵化壳聚糖（QACS-mPEG）,反相悬浮法制备二乙烯基砜交联QACS-mPEG微球。用FTIR、1 H NMR、EA和SEM对产物进行表征,并且以酮洛芬为模型药物研究微球的载药性能及释放行为。结果表明,mPEG和季铵盐基团的引入提高了N-mPEG-O-季铵化壳聚糖微球的载药量,为4.31mg/mg;载药N-mPEG-O-季铵化壳聚糖微球在模拟肠液的缓释效果优于胃液,微球释药具有pH响应性。     

复合玉米淀粉微球的合成与其性能研究

以复合淀粉(玉米淀粉和β-环糊精)为原料,N,N’-亚甲基双丙烯酰胺和环氧氯丙烷为交联剂,采用反相乳液聚合法,合成复合玉米淀粉微球。利用红外光谱、扫描电镜、差热分析等方法对微球进行了表征,并用溶胀度法测定微球交联程度,通过微球对无机金属粒子和有机色素吸附量测定微球的吸附性能。结果表明,制备的复合玉米淀粉微球外型规则,粒度均匀,分散性好。复合玉米淀粉微球的溶胀度比玉米淀粉降低,对无机物Ca2+、有机物胭脂红的吸附作用比玉米淀粉更强,可以作为良好的吸附剂。     

Fabrication and characterization of multilayer SiO2/polymethacrylic acid/polypyrrole composites and hollow polypyrrole microspheres

Methacrylic acid was polymerized on the 3‐(methacryloxy)propyl trimethoxysilane‐modified silica core. The carboxylic acid groups of polymethacrylic acid (PMAA) not only provide the “active‐sites” for growth of the pyrrole monomers but also act as doping acids for polypyrrole (PPy). By in situ polymerization route, SiO₂/PMAA/PPy multilayer composites and hollow PPy microspheres with controllable shell thickness were fabricated. The morphologies, sizes, and structures of the nanocomposites were investigated in detail by transmission electron microscopy, scanning electron microscopy, Fourier‐transform infrared spectra, X‐ray photoelectron spectroscopy, and thermogravimetric analysis. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Incorporation of HSA Microparticles Within the Taxol-Loaded In Situ Forming PLGA Microspheres: Synthesis,Characterization, and Drug Release

Taxol-loaded poly(lactic acid-co-glycolic acid) (PLGA) microspheres containing different portions of human serum albumin microparticles (mHSA) were prepared via an in situ forming method. mHSA was obtained using a freezing-induced phase separation method and further surface modified via PLGA chains (g-mHSA). Surface modification of mHSA improved their dispersion within microspheres. Incorporation of 3% mHSA within microspheres increased their size and surface porosity, while g-mHSA decreased their size. Addition of 1.5% and 3% mHSA into microspheres decreased their initial burst release from 40.7% to 21.1% and 10.2%, respectively. Microspheres consisting 1.5% and 3% g-mHSA displayed 29.9% and 33.1% initial burst release, respectively.     

羧基磁性高分子微球的制备和表征

用改进的悬浮聚合法制备了表面含有羧基功能团的聚苯乙烯磁性微球。考察了磁微球的形态与结构 ,测定了磁微球的粒径与磁响应性 ,主要研究了单体 /水、丙烯酸 /单体、反应温度和反应时间对磁性微球形成的影响 ,并对磁性微球的生物吸附活性进行了表征。优化得到了制备具有良好生物吸附活性的羧基磁性微球的最佳实验条件     

核壳结构PMMA纳米微球增韧R-PVC/CPE

研究了核壳结构聚甲基丙烯酸甲酯（PMMA）纳米微球对硬质聚氯乙烯/氯化聚乙烯（R-PVC/CPE）体系的增韧和增强作用及其对加工流变性的影响。研究发现,核壳结构PMMA纳米微球与R-PVC/CPE基体在适当配比下共混,在显著提高基体的冲击强度的同时,拉伸强度、伸长率和加工流变性也有改善。     

Polyamide 66 microspheres metallised with in situ synthesised gold nanoparticles for a catalytic application

A simple concept is proposed to metallise polyamide 66 (PA66) spherulite structures with in situ synthesised gold nanoparticles (Au NPs) using a wet chemical method. This cost-effective approach, applied to produce a PA66/Au NP hybrid material, offers the advantages of controlling the nanoparticle size, the size distribution and the organic-inorganic interactions. These are the key factors that have to be controlled to construct consistent Au nanostructures which are essential for producing the catalytic activities of interest. The hybrid materials obtained are characterised by means of scanning electron microscopy, transmission electron microscopy, attenuated total reflection-Fourier transform infrared spectrometry and X-ray diffraction spectrometry. The results show that PA66 microspheres obtained via the crystallisation process are coated with Au NPs of 13 nm in size. It was found that controlling the metal coordination is the key parameter to template the Au NPs on the spherulite surfaces. The preparation processes and the key factors leading to the formation of PA66 spherulites coated with Au NPs are discussed. Moreover, the efficiency of the coated spherulites as a potential catalyst is proved by demonstrating the reduction of methylene blue via UV-visible spectrometry.     

Carbonaceous microsphere-based superabsorbent polymer as filler for coating of NPK fertilizer: Fabrication,properties, swelling,and nitrogen release characteristics

Recently, the use of controlled release fertilizers in agriculture has resulted in huge benefits in plant growth and cultivation. Superabsorbent polymer (SAP)-coated fertilizers have the added advantage in retaining water in soil after irrigation and also reduce the nutrient release rate from soil in a controlled manner. This study aimed to produce a nitrogen–phosphorus–potassium (NPK) fertilizer coated with superabsorbent carbonaceous microspheres polymer (SPC) by inverse suspension polymerization method with water-retention and controlled release properties. Two sets of experiments were conducted: (1) three different weight percentages and (2) different materials. NPK coated with SPC showed increasing water-retention ability with respect to carbon microsphere percentages and retains >80% water at the 30th day of experiment compared with pure NPK and NPK coated with SAP. The slow release behavior of all samples was investigated by induced coupled plasma mass spectrometry spectrometry and results showed that NPK coated with SAP and SPC has a low release rate with <50% nutrient release compared with uncoated NPK at the 30th day. The release mechanism kinetics of NPK coated with SAP and SPC were studied based on the Kosmeyer–Peppas model. The mechanisms approached Fickian diffusion-controlled release as the n value for both samples was less than 0.5. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48396.     

葡聚糖接枝型高载量金属螯合介质的制备与性能

对琼脂糖凝胶微球进行烯丙基活化,再接枝葡聚糖分子,考察葡聚糖分子量等因素对葡聚糖接枝过程的影响;以葡聚糖接枝琼脂糖凝胶微球为基质,制备亚氨基二乙酸型金属螯合介质,考察葡聚糖接枝过程对金属螯合介质的孔道结构、流通性能和载量等的影响. 结果表明,分子量20~500 kDa的葡聚糖都能均匀分布于琼脂糖凝胶微球内,葡聚糖接枝量随分子量增加而增大,所制的金属螯合介质形貌、粒径及其分布基本不受影响,且具有更好的流通性能,孔道结构比商品介质Ni Sepharose 6FF更丰富. 葡聚糖接枝的金属螯合介质对带组氨酸标签的乳酸脱氢酶和睫状神经营养因子的载量分别达到19和27 mg/mL,较Ni Sepharose 6FF的载量分别提高26.6%和42.0%.     

PMMA@SCNC composite microspheres prepared from pickering emulsion template as curcumin delivery carriers

We demonstrate a facile route to prepare novel composite microspheres based on Pickering emulsion template stabilized by cellulose nanocrystals prepared from sisal fiber (SCNCs). The oil phase of the Pickering emulsions contains hydrophobic drug curcumin and poly(methyl methacrylate) (PMMA). Curcumin loaded PMMA composite microspheres coated by SCNCs (Cur‐loaded PMMA@SCNC CMs) were obtained after the evaporation of dichloromethane. The structure and morphology of CMs were characterized by polarized optical microscope (POM), confocal laser scanning microscope, scanning electric microscope, and Fourier transform infrared spectroscopy. The stability and release kinetics of curcumin were evaluated based on spectrophotometric measurements. Overall, these results show that Cur‐loaded PMMA@SCNC CMs display long‐term photostability and good encapsulating ability for curcumin. This work offers an effective route of preparing new functional microsphere for the delivery of bioactive compounds. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46127.