纳米介孔分子筛用于吡格列酮长效缓释的研究

主要研究以CTAB（十六烷基三甲基溴化铵）为模板剂,TEOS（正硅酸乙酯）为硅源的二氧化硅介孔材料（MCM-41）作为药物盐酸吡格列酮输送体系的可能性,研究药物在这种介孔材料中的吸附/释放特性及其影响因素。采用粉末X射线衍射法（XRD）,傅里叶变换红外光谱法（FT-IR）和扫描电子显微镜（SEM）来表征吸附前后的介孔分子筛。将合成的分子筛用作吡格列酮药物的载体,实时检测制备药物在模拟胃液中的释放过程发现,在药物释放开始后的第1h内,吡格列酮释放速率非常快,1h后释放率达到17.93%,在9h后释放率达到37.88%,在释放34h后,释放率达到62.74%。     

制备条件对介孔分子筛MCM-41形貌的影响研究

本文以正硅酸乙酯(TEOS)为硅源,十六烷基三甲基溴化铵(CTAB)为介孔模板剂制备MCM-41介孔分子筛,通过改变制备体系条件来调控MCM-41的形貌,考察了制备体系水用量、制备体系氨水用量、TEOS滴加速率对所得MCM-41产物形貌的影响。结果表明:制备体系水用量和氨水用量增大会使所得产物由棒状向球形颗粒转变,TEOS滴加速率加快有利于形成尺寸均匀的棒状MCM-41。最后对MCM-41形貌演变过程进行了分析。     

稀土-MCM-41介孔分子筛的合成与应用研究

从合成方法、表征与性质测试、催化应用等方面对稀土 -MCM -4 1介孔分子筛的研究作简要评述。     

全硅介孔分子筛MCM-41的表面修饰及其疏水性

在极性溶剂(丙酮)或非极性溶剂(甲苯)中,用三甲基氯硅烷对全硅介孔分子筛MCM-41进行了表面修饰。利用IR、XRD和低温N2吸附-脱附等手段对样品进行了结构分析;并通过测定样品在水或正庚烷饱和蒸汽中的吸附量,研究了它们的疏水性。实验结果表明,表面改性后的MCM-41仍保持完好的介孔结构,由于有机官能团接枝在MCM-41的内表面,占据了孔道内部空间,使其比表面积、孔容和孔径都减小。样品的疏水性与其硅烷化程度成正关系,且在非极性溶剂中表面修饰的样品表现出更好的疏水性能。     

MCM-41的制备及用于吡拉西坦缓释性能研究

以十六烷基三甲基溴化铵（CTAB）为模板剂,正硅酸乙酯（TEOS）为硅源,合成MCM-41分子筛.以其做载体,吡拉西坦为模型药物,研究了吡拉西坦在MCM-41分子筛的负载与释放性能.并通过扫描电子显微镜（SEM）、粉末X-射线衍射（XRD）和傅立叶变换红外光谱（FT-IR）等方法对MCM-41分子筛以及负载吡拉西坦后的样品进行表征.研究了吡拉西坦的负载量及释放性能,定时检测了制备药物在模拟体液中的释放过程,从而确定以MCM-41作为吡拉西坦缓释载体的可能性.     

MCM-41介孔分子筛的改性和应用

综述了近年来通过搀杂、有机官能化、负载的方法改性MCM-41介孔分子筛的研究情况,重点介绍了MCM-41介孔分子筛在化工、环保、生物医学领域的应用现状。     

MCM-41介孔分子筛改性研究进展

介绍了有序介孔材料的定义和分类,MCM-41介孔分子筛、合成方法和形成机理,针对其MCM-41目前存在的一些问题,综述了国内外对MCM-41介孔分子筛最新的改性研究进展。     

硅源对纯硅MCM-41介孔分子筛结构性能的影响

分别采用正硅酸乙酯(TEOS)、气相法白炭黑、硅溶胶为硅源,十六烷基三乙基溴化铵(CTEAB)为结构导向剂,在100℃用水热晶化法在碱性(NaOH)介质中反应5d,合成出MCM-41介孔分子筛样品。通过XRD、N2吸附-脱附测试手段对不同硅源合成的样品进行了对比表征分析,实验结果表明,相对于TEOS作为硅源,气相法白炭黑和硅溶胶制得的MCM-41具有较大的孔径(>4nm)和孔容(>1cm3/g)以及高的比表面积(1000m2/g),在制备大孔径的介孔MCM-41时,气相法白炭黑和硅溶胶是两种比较好的硅源。     

介孔MCM—41分子筛水热稳定性的研究进展

综述了近年来关于各种增强介孔MCM-41分子筛水热稳定性的方法,分析比较了各种方法的特点,阐释了各种方法的作用机理,最后指出了提高分子筛水热稳定性的发展前景.     

微波法合成MCM-41介孔分子筛及吸附性能研究

以十六烷基三甲基氯化铵为模板剂,在微波实验条件下合成MCM-41介孔分子筛,缩短了合成时间,降低产品成本。实验考察了多种因素对MCM-41合成的影响,并通过吸附处理亚甲基蓝溶液能力强弱,得到最佳合成条件：摩尔比1TEOS：0.2CTMACl：160H2O,pH为10,晶化时间15 min。通过红外光谱分析,MCM-41分子筛的主要特征吸收峰均已出现,说明合成分子筛MCM-41成功。     

Long time release of water soluble drug from hydrophilic nanofibrous material

In this study, mesoporous silica nanoparticles (MSNs) were embedded into the hydrophilic poly(vinyl alcohol) (PVA) nanofibrous mats to achieve sustained release of water soluble drug from hydrophilic nanofibrous mats. MSNs were successfully prepared based on a sol–gel method. Water soluble drug naproxen sodium was then loaded into the mesopores of the MSNs, and different amounts of the drug-loaded MSNs were further incorporated into the fibers by the electrospinning process. Morphology of the nanofibrous mats was investigated, and it was found that all the fibers exhibited fibrous structure. Interestingly, lots of protrusions could be observed from the scanning electron microscopy images with high magnification, and numbers of the protrusions increased with the increasing of loading ratios of the MSNs from 5 to 15%. In addition, the wetting behaviors of the nanofibrous mats were also measured, and the water contact angles of all the mats were measured to be 0°. Finally, the drug release results indicated that all the PVA/MSNs composite nanofibrous mats showed an obviously prolonged drug release. The optimal loading ratio of the MSNs in the nanofibers was 10% due to the slowest drug release rate. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47922.     

One-pot synthesis of conjugated nitroalkenes by diamino-functionalised mesoporous material

Nitroalkenes are synthesised for the first time in a one-pot liquid-phase procedure from carbonyl compounds and nitroalkanes using organic-diamine-functionalised mesoporous material (MCM-41) as the catalyst. The yields are reasonable to excellent and the reaction conditions are mild. The hybrid solid base catalyst can be recycled several times with consistent activity. This revised version was published online in July 2006 with corrections to the Cover Date.     

Synthesis of a mesoporous material from two natural sources

Mesoporous materials were obtained from two natural silica sources, diatomite and pumicite, under hydrothermal conditions, autogenic pressure and in presence of the surfactant cetyltrimethylammonium bromide (CTAB) as the template. Using diatomite, a temperature of 383 K and the following molar ratios in the initial reaction gel: SiO₂/Al₂O₃ = 8.86; CTAB/SiO₂ = 0.1; Na₂O/SiO₂ = 0.10–0.25 and H₂O/Na₂O = 250–300, the mesoporous material MCM‐41 was obtained in a reaction time of 48 h. When pumicite was used, a mesoporous material was obtained in a reaction time of 96 h, a reaction temperature of 423 K and an initial reaction gel with the following molar ratios: SiO₂/Al₂O₃ = 8.86; CTAB/SiO₂ = 0.1; Na₂O/SiO₂ = 0.25 and H₂O/Na₂O = 330. Copyright © 2006 Society of Chemical Industry     

阿司匹林微胶囊的制备及其体外释放行为的研究

近年来,微胶囊技术在生物医药、化工、食品等行业得到了广泛应用和发展.以液中干燥法制备阿司匹林微胶囊,研究了微胶囊的形成过程、表观形貌、粒度及其体外释放行为.研究结果表明,阿司匹林微胶囊形成过程中,乙基纤维素分散成球,继而在各微球表面析出,微球越来越细密,表面空洞减小,最终形成完整的微胶囊.微胶囊表面致密、光滑,有少量细小的孔洞,多数呈球形,但粒度不均匀,有不规则杂片存在.粒度基本呈正态分布,平均粒径为1 445 nm.随着制备微胶囊过程中阿司匹林原料药加入量的增加,微胶囊成品的实际载药量增加,但其包覆率却随之减小.在体外释放初始阶段,微胶囊中阿司匹林的释放较快,继而释放速率减慢呈缓慢上升趋势.加入少量药品制备的微胶囊中阿司匹林释放速度较大.     

Biodegradable polyesterurethane networks for controlled release of aspirin

In this article, poly(D,L‐lactide‐co‐glycolide)urethane (PULG) networks were prepared from hydroxyl telechelic star‐shaped oligo(D,L‐lactide‐co‐glycolide) coupled with 1,6‐diisocyanate‐2,2,4‐trimethylhexane and 1,6‐diisocyanate‐2,4,4‐trimethylhexane or isophorone diisocyanate. The release of model drug aspirin (ASP) from biodegradable polyesterurethane networks was studied in phosphate buffered saline pH = 7.0 at 37°C. PULG networks turned from transparent to opaque after ASP loading. PULG networks with lower crosslinking density always resulted in higher drug loaded content. The results of differential scanning calorimetry and scanning electron microscope measurements demonstrated that ASP was uniformly distributed in the networks. The drug release courses of ASP from PULG networks in phosphate buffered saline pH = 7.0 at 37°C could be divided into three stages. Firstly, ASP release was at approximately uniform rate from PULG networks; Secondly, the release rate obviously increased due to the degradation of the PULG networks; Thirdly, the release rate decreased gradually because most of the ASP had diffused out of the PULG networks. The crosslinking density of polyesterurethane networks also affected both degradation of the polymer networks and drug release rate. The in vitro release test revealed that ASP accelerated the degradation process of PULG, which exhibited a typical erosion‐controlled release mechanism. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

新型纳米MCM-41合成研究

本实验合成未脱除模板剂的MCM-41分子筛,然后进行焙烧使模板剂炭化,生成碳纳米丝,留在孔道中。对MCM-41进行XRD检测,考察了晶化温度、晶化时间、硅铝比、水量等各因数的影响。结果表明,强酸性介孔晶体分子筛的生成,受铝含量的影响很大,模板剂的用量增加也有利于产物的生成,受水含量的影响不大。在实验的基础上,对一些不理想的步骤也提出了一些改进方法。     

缓释片剂的研究概况

综述了近年来缓释片剂的研究概况。目前上市的缓释片主要包括骨架缓释片、包衣缓释片、多层缓释片等。对缓释片剂的分类与制备、应用的辅料以及质量控制方法进行了介绍。     

Kinetic studies on the irinotecan release based on structural properties of functionalized mesoporous-silica supports

Building a detailed kinetic model for the drug release from an ordered mesoporous support is a difficult task due to various physico-chemical processes involved, including complex adsorption-desorption and diffusion steps. A compartmented mechanistic model for the drug release from a silica mesoporous (functionalized) support is elaborated to correlate the experimental drug release data under various release conditions. The identified model parameters are interpreted in relationship to the delivery system characteristics (drug, support, and linker properties) to be used for designing a system with a controlled release. Extended model predictions are compared with those of various semi-empirical or overall diffusion models in terms of quality (adequacy, validity, reliability) and parameter significance to determine the information loss when simplified models are used for design purposes. Exemplification is made for the release of irinotecan from a MCM-41 support unfunctionalized vs. functionalized with 3-aminopropyl triethoxysilane or triethoxyvinylsilane in a synthetic intestinal fluid.