含稀土铕配合物三维有序大孔材料的制备及其荧光性能

采用物理吸附的方法将稀土配合物嵌入三维有序大孔聚合物材料的孔内,组装了发光性能良好的含邻菲罗林-铕配合物的三维有序大孔聚合物材料(3DOM/Eu(Phen)2).并通过扫描电镜、红外光谱和荧光光谱对3DOM/Eu(Phen)2组装体进行了表征.结果表明:组装体的结构保持了三维有序大孔材料的结构特征,在紫外灯的照射下,发出稀土离子的特征谱线,与纯配合物相比,其激发光谱发生蓝移,荧光寿命延长.     

三维有序大孔炭的设计构筑、性能及应用研究

多孔炭材料具有高的比表面积、发达的孔结构、耐热、耐腐蚀、无毒无害、价廉、易操作等特点,以其为研究核心,在学术界和工业界均具有广阔的应用前景。通过胶晶模板法合成孔径在亚微米范围内的三维有序大孔炭,其高度规整的孔道结构,在吸附分离、催化和电极等领域已展现出巨大的应用潜能。利用双模板法将介孔结构融汇于三维有序大孔炭的孔壁中,设计构筑出三维有序大孔-介孔炭,势必会显著增强其应用价值。本文主要阐述了以胶晶为主体模板制备三维有序大孔炭的各种路径;采用双模板法将介孔引入大孔通道内获取三维有序大孔-介孔炭;探索影响孔结构参数的主要因素,并与各种功能材料复合增强其性能;着重对三维有序大孔炭及大孔-介孔炭在环境净化和新型能源转化与储备领域的应用进行概述。     

红荧烯反蛋白石的制备及其光学性质研究

通过表面浸润法制备了红荧烯的反蛋白石结构,成功观测到其结构色,并检测出相对应反射光谱.此类方法可进一步拓展制备多种具有三维有序大孔结构的有机半导体材料,得到新的光电性质.     

三维有序大孔-介孔二氧化硅的可控制备及表征

以聚甲基丙烯酸甲酯(PMMA)胶晶为大孔模板、嵌段共聚物P123为介孔模板,利用双模板剂法进行了三维有序大孔-介孔二氧化硅材料的制备研究。采用SEM、TEM、低角XRD以及N₂吸脱附技术对样品进行了表征。结果表明,通过简单的调控PMMA胶晶模板的组装过程,就可以调变合成材料中的大孔结构,从而轻松地实现可控的制备出具有网状或者层状结构的三维有序大孔-介孔二氧化硅材料,并提出了其可能的形成机理。此外,所制备的三维有序大孔-介孔二氧化硅样品均具有较大的BET比表面积(>550m₂·g^-1),大孔孔径200nm左右,介孔孔径分布集中于3.5nm左右。     

异硫氰酸荧光纳米复合粒子的研制与应用

采用改进的St ber法制备了二氧化硅外壳的纳米复合荧光粒子。利用异硫氰酸荧光素(FITC)与3-氨基丙基三乙氧基硅烷(APTEOS)反应制备前驱体,再用正硅酸乙酯(TEOS)在一定的条件下水解与缩合,制备有机-无机纳米复合荧光颗粒,利用透射电子显微镜(TEM)测试表明,此纳米复合颗粒呈球形、大小均一,直径约为70 nm。制备的纳米复合荧光粒子经过多次水洗后,仍有较强的荧光特性,有效地防止FITC泄露。用激光共聚焦显微镜观测纳米复合荧光粒子标记的牛血清白蛋白(BSA),可以明显看出BSA上的绿色荧光。     

三维有序大孔Al2O3制备的新方法及表征

以聚苯乙烯胶晶为模板,用Al(NO3)3•9H2O为前驱物,使用柠檬酸为配体,成功地制备了孔径为250～350 nm的三维有序大孔Al2O3材料.SEM观察表明,所得大孔材料孔结构规则排列,孔与孔之间通过小孔相连,形成了一个三维有序排列的蜂窝状结构.实验发现,以Al(NO3)3•9H2O为前驱物,加入柠檬酸可以防止团聚粒子的产生,有利于三维有序结构的形成.前驱物浓度在0.5～0.8 mol•L－1范围内均能得到较好的三维有序大孔结构.在1 100 ℃焙烧2 h后,Al2O3大孔材料仍能保持完整的规则孔结构特征,表现出较高的热稳定性.     

应用FRAP技术评价蛋白在聚丙烯酰胺-丙烯酸凝胶中的扩散行为

药物分子从药物载体中的释放行为与载体的结构有密切关系.本实验中采用丙烯酰胺和丙烯酸等材料,运用水相沉淀的方法,制备了4种不同单体配比的聚丙烯酰胺-丙烯酸(P(Am-co-Ac))共聚物水凝胶.运用红外分析方法对P(Am-co-Ac)组成进行表征.使用荧光漂白恢复法(FRAP,fluorescence recovery after photobleaching)观察荧光素FITC标记的牛血清白蛋白(BSA)在聚丙烯酰胺-丙烯酸中的扩散行为,并以激光共聚焦显微镜进行实时成像.实验表明,FITC-BSA在不同单体配比的共聚物中的扩散系数是不同的.通过调节聚合物中单体的配比能够达到控制蛋白释放速率的作用,从而为调控蛋白和多肽类药物的缓控释放提供了可能性.     

硝酸盐制备三维有序大孔金属氧化物材料研究

用硝酸盐、柠檬酸和乙醇/水按一定摩尔比配置成前驱物溶液, 采用胶晶模板法, 制备了三维有序大孔金属氧化物材料: Al₂O₃, CeO₂, Cr₂O₃, NiO, MgO, In₂O₃, CeO₂/Al₂O₃, Cr₂O₃/Al₂O₃和NiO/Al₂O₃. SEM观察表明, 材料中大孔有序排列, 大孔间由小孔相连, 形成三维规则的笼状网络结构. XRD和TEM测试表明, 大孔孔壁由具有纳米尺寸的金属氧化物粒子组成. 实验表明, 加入乙醇、柠檬酸, 提高溶液对胶球润湿性, 改善溶液渗透能力, 避免粒子团聚, 有利于有序大孔结构的形成. 这一研究表明, 根据硝酸盐的物理化学性质, 调整溶液组成, 选择合适的热处理温度, 能得到大孔排列有序、三维规整性好的大孔结构材料. 此法具有原料易得, 操作简单的特点, 是3DOM材料的一种新型高效制备路线.     

有序大孔材料的制备及其应用

本文综述了近年来有序大孔材料的制备及应用.有序大孔材料的制备方法有胶态晶体模板法、生物模板法及其它模板法,重点阐述了用胶态晶体为模板制备有序大孔材料,如大孔金属、大孔无机氧化物、大孔碳、大孔半导体、大孔无机盐、大孔碳/无机氧化物复合物和大孔有机聚合物.用胶态晶体为模板制备有序大孔材料在催化、吸附、分离、传感器、光子晶体和声学等领域有潜在的应用.     

硫辅助合成高孔隙率大孔氮化硼材料

采用硫粉辅助的方法合成了具有一定有序孔洞结构的三维大孔氮化硼材料,具有高比表面积(230 m2.g-1)和高孔隙率(85.6%),并呈现开孔结构。在未加入硫粉的情况下则只形成完全无序的三维大孔氮化硼,并且比表面积和孔隙率分别降至122m2.g-1和73.7%。热重测试表明两种产品均具有良好的抗氧化性能。本文还对这种大孔材料的形成过程和硫粉的作用进行了初步的探讨。     

Structural Transformation of Bovine Serum Albumin Induced by Dimethyl Sulfoxide and Probed by Fluorescence Correlation Spectroscopy and Additional Methods

Determining the structure of a protein and its transformation under different conditions is key to understanding its activity. The structural stability and activity of proteins in aqueous–organic solvent mixtures, which is an intriguing topic of research in biochemistry, is dependent on the nature of the protein and the properties of the medium. Herein, the effect of a commonly used cosolvent, dimethyl sulfoxide (DMSO), on the structure and conformational dynamics of bovine serum albumin (BSA) protein is studied by fluorescence correlation spectroscopy (FCS) measurements on fluorescein isothiocyanate (FITC)‐labeled BSA. The FCS study reveals a change of the hydrodynamic radius of BSA from 3.7 nm in the native state to 7.0 nm in the presence of 40 % DMSO, which suggests complete unfolding of the protein under these conditions. Fluorescence self‐quenching of FITC has been exploited to understand the conformational dynamics of BSA. The time constant of the conformational dynamics of BSA is found to change from 35 μs in its native state to 50 μs as the protein unfolds with increasing DMSO concentration. The FCS results are corroborated by the near‐UV circular dichroism spectra of the protein, which suggest a loss of its tertiary structure with increasing concentration of DMSO. The intrinsic fluorescence of BSA and the fluorescence response of 1‐anilinonaphthalene‐8‐sulfonic acid, used as a probe molecule, provide information that is consistent with the FCS measurements, except that aggregation of BSA is observed in the presence of 40 % DMSO in the ensemble measurements.     

Solid-support fluorescent derivatization of picomoles of protein at low concentration with FITC

A new method based on solid-support reaction is described to realize fluorescent derivatization of proteins at concentrations as low as 10⁻⁸ M. A simple, low-cost homemade capillary C18 cartridge was fabricated as the solid-support reactor. Using bovine serum albumin (BSA) as a test protein, we demonstrated that the protein can be captured by this reactor and then labeled by fluorescein isothiocyanate (FITC, isomer I) on solid-support. Unwanted fluorescent intruder (excrescent FITC and products of secondary reactions) were removed from target easily. The analysis by nano-HPLC with laser-induced fluorescence (LIF) detection was described. The effect of reaction conditions on the derivatization has been evaluated and discussed. The use of the solid-support reactor allows easy handling of as little as 8.5 pmol of BSA. A fraction from weak anion-exchange chromatography (WAX) of human liver extract was used as an illustrative example of application to real samples.     

荧光各向异性法快速测定荧光标记物对蛋白质的标记比

免疫荧光技术是免疫学检测的重要手段之一,该技术在病原微生物的早期诊断、自身免疫研究、抗原或抗体的免疫组化定位等方面都得到了广泛应用^[1].荧光色素对抗体(或抗原)标记比的测定是免疫荧光技术的重要部分.     

Adsorption of bovine serum albumin on polyelectrolyte-coated glass substrates: applications to colloidal lithography

The adsorption of bovine serum albumin (BSA) labeled with fluorescein isothiocyanate (FITC) on polyelectrolyte-coated glass substrates was investigated using fluorescence microscopy. Glass substrates may inhibit adsorption of proteins due to electrostatic repulsion. However, when the substrate is modified with a thin film of positively charged polyelectrolytes, proteins can be adsorbed due to the attractive electrostatic interactions. In this study, poly(allylamine-hydrochloride) (PAH) molecules, which have positively charged amino groups at pH 7, were used to generate a positively charged layer on the glass substrate. A surfactant, sodium dodecyl sulphate (SDS), was used to alter the glass-protein interaction and subsequently modulate the coverage of adsorbed protein. We applied this technique to control the heterogeneously charged microscopic patterns of biomolecules created when the adsorption of protein is done in conjunction with colloidal lithography.     

FITC标记脂肪酶的稳定性和荧光光谱

脂肪酶;异硫氰基荧光素(FITC);荧光光谱;稳定性     

Biotin induced fluorescence enhancement in resonance energy transfer and application for bioassay

A novel method to significantly enhance fluorescence resonance energy transfer (FRET) signal which occurred from fluoresceine isothiocyanate (FITC) to Dylight 549 was studied in this paper. Streptavidin was labeled with the donor fluorophore FITC and biotinamide was conjugated to the acceptor Dylight 549. When biotinamide bound to streptavidin, FRET would occur from FITC to Dylight 549 while a remarkable fluorescence enhancement of streptavidin-FITC was observed. The fluorescence enhancement of streptavidin-FITC in the presence of biotin was utilized in the FRET system to obtain higher fluorescence signal. Increase of fluorescence intensity of FITC and decrease of Dylight 549 depended on the concentration of competitive biotin. A homogeneous analysis method was established based on the fluorescence recovery of FITC in the FRET system with fluorescence enhancement. This method is highly sensitive and simple to determine the concentration of biotin. The detection limit for biotin was 0.5 nM and the linear range of the assay was 0.8-9.8 nM. The response time is no more than 15 min during the one-step assay due to the high affinity between streptavidin and biotin.     

电泳芯片的制作及其进样与分离

利用微细加工技术研究在玻璃上制作电泳芯片的方法,测试了微管道的伏安特性曲线。在该电泳芯片上进行了注样和分离实验,采用激光诱导荧光法进行检测,利用CCD拍摄了进样和分离的全过程。分析了电泳芯片上施加不同的电压对样品注样的影响,给出了FITC－OH和FITC－Arg分离谱图。     

包埋于PLGA膜中的BSA海藻酸钙微球的制备及其释放行为

在组织工程中，为了促进和调节细胞在细胞支架上的增殖和分化，一些特殊的生物活性分子(生长因子(Growth Factor，简称GF))，必须引入支架．这些生长因子是一类具有诱导和刺激细胞增殖、维持细胞存活等生物效应的多肽蛋白类物质，因此，在组织工程研究中，生长因子是三个重要因素之一，     

荧光光谱跟踪结冷胶水溶液的溶液-凝胶转变

将异硫氰酸荧光黄(FITC)标记在结冷胶分子链,用荧光光谱跟踪了结冷胶水溶液凝胶化过程中FITC荧光强度和各向异性比的变化.结果表明在结冷胶的凝胶化转变中,FITC的荧光相对强度和各向异性随温度降低而增大,在某一温度荧光相对强度和各向异性比对温度的曲线出现了明显的转折点,这个转折点的温度低于流变温度扫描曲线中G′=G″的温度.利用荧光的方法确定物理交联体系的关于重均聚合度和凝胶分数的相关临界指数γ和β.γ和β不符合Flory-Stockmayer和逾渗模型的预测.