树枝状介孔二氧化硅的研究进展

介绍了树枝状介孔二氧化硅的三种合成方法,分别是微乳液合成、两相界面合成及球形胶束自组装合成法,为精确调节树枝状介孔二氧化硅的结构,探讨了不同方法可能的形成机理.由于球形胶束自组装合成法的绿色经济,重点讨论了球形胶束自组装合成法的发展及形成机理.介绍了树枝状介孔二氧化硅纳米材料在催化和生物医学方面的应用效果,并对树枝状介...     

基于中心辐射树枝状介孔二氧化硅构筑CPO固定化酶反应器及应用

首先制备粒径均匀的具有开放的三维中心辐射树枝状结构的介孔二氧化硅(DSP)粒子, 再通过静电相互作用在孔道内负载氯过氧化物酶(CPO)构筑了CPO@DSP固定化酶反应器. 通过改变硅源正硅酸乙酯(TEOS)和模板剂十六烷基三甲基氯化铵(CTAC)的浓度调控孔径大小, 研究了孔径对固定化酶反应器催化活性的影响; 同时基于酶促反应动力学分析探讨了孔道内酶催化反应的限域效应, 并进一步在CPO@DSP表面包覆海藻酸钠(SA)水凝胶薄膜以抑制酶反应器在使用过程中酶分子的泄露, 所得SA-CPO@DSP固定化酶反应器的重复使用性显著提高, 循环使用10次后, 仍能保持90%以上的催化活性. 将SA-CPO@DSP酶反应器用于环境水体中残留抗生素左氧氟沙星的降解, 对100 μg/mL的底物在25 min内降解率可达88%以上; 将该反应器用于苯酚的视觉比色检测, 裸眼可检测到5 μmol/L的苯酚, 表明SA-CPO@DSP酶反应器在环境保护方面具有良好的应用前景.     

蜘蛛丝素和聚乙烯醇固定葡萄糖氧化酶 制备葡萄糖传感器

用蜘蛛丝素和聚乙烯醇的混合材料把葡萄糖氧化酶固定在氧电极表面,制成葡萄糖氧化酶电极。传感器对葡萄糖有灵敏的响应,平均响应时间为20s,电位变化值与葡萄糖浓度在3.0×10     

壳聚糖-Cu^2＋复合物膜固定葡萄糖氧化酶用于葡萄糖传感

利用壳聚糖(CS)对Cu2 的配位吸附作用,制得壳聚糖-Cu2 复合膜修饰电极,进一步通过Cu2 与蛋白质的配位作用,再将葡萄糖氧化酶(GOD)固定在金电极上制得GOD-Cu2 -CS/Au电极.该酶电极检测葡萄糖的线性范围为0.03～2.5 mmol·L-1,线性相关系数为0.997,检出限(S/N=3)为1 μmol·L-1.以电化学石英晶体微天平(EQCM)技术监测了各修饰过程.     

不同酸对介孔二氧化硅球表面形貌和介相结构的影响

在室温、不同酸性条件下合成出微米级球形介孔二氧化硅材料，通过XRD、SEM以及氮气吸附等手段对介孔二氧化硅材料进行了表征。用TEM跟踪不同反应时间介孔二氧化硅球的形成，对这些球颗粒的合成机理进行了讨论，同时探讨了不同酸性条件下介孔二氧化硅表面形貌和介相结构的变化。     

葡萄糖氧化酶共价交联于蛋膜上的葡萄糖传感器

以牛血清白蛋白－戊二醛为交联剂，将葡萄糖氧化酶固定地鸡蛋膜上，氧电极作电化学敏感元件，制成葡萄糖氧化酶电极。传感器的响应范围为４．０×１０＾－６－２．４×１０＾－３ｍｏｌ／Ｌ；检测限为１．２１０＾－６ｍｏｌ／Ｌ。该传感器具有线性范围宽，灵敏度高，使用寿命长等优点。     

有序介孔二氧化硅/聚苯胺复合物

本文综述了有序介孔二氧化硅/聚苯胺复合物从出现至今的10余年里的研究进展,介绍了复合物的合成方法,包括气相法、液相法和一步合成法,以及模板剂单体原位合成法等。引入苯胺单体后在孔道内聚合生成聚苯胺,即聚苯胺与有序介孔二氧化硅形成了复合物。该复合物的结构和形貌,以及孔道中聚苯胺的结构形态和电学性质,与本体聚苯胺相比具有显著的变化。这种以有序介孔二氧化硅为模板制备的聚苯胺的单分子导线,有潜力应用在新型的电子或光电子器件上。此外,该复合物因为其独特性质很可能在燃料电池的聚合物电解质膜、湿度传感器、电流变材料以及电化学电容器等方面得到应用。     

甲酰胺对有序介孔二氧化硅形貌的影响

At room temperature and in acidic solution, ordered mesoporous silicas with particular morphology were synthesized using cetylpyridinium chloride as the template and formamide as the cosolvent. Scanning electron microscope (SEM), small angle X-ray diffraction (SXRD), and nitrogen adsorption techniques were used to characterize the as-synthesized and calcined samples. Results showed that the samples had hexagonal mesostructure analogous to MCM-41 and relatively narrow pore-size distributions (BJH). Besides, BET surface areas of the samples were in the range of 1 000～1 250 m²·g^-1 and high total pore volumes were up to 1.367 cm³·g^-1. Addition of formamide affected obviously mesostructures and the morphology of the mesoporous silica. Furthermore, with the increase of the concentration of formamide, the unit-cell constant decreased and particle shape changed from gyroids to fibers.     

介孔碳修饰玻碳电极上葡萄糖氧化酶的直接电化学

使用简单的方法将葡萄糖氧化酶(GOD)固定在介孔碳(Mesoporous Carbon)修饰的玻碳电极(GCE)表面.循环伏安测试表明:修饰电极上的GOD在0.1mol/L磷酸缓冲溶液(PBS)(pH=7.1)中发生了准可逆的氧化还原反应,其克式量电位为-0.4294 V,并且该电化学反应包含有两电子两质子的传递.在氮气饱和的情况下,以羧基二茂铁作为电子传递中介体,GOD能将葡萄糖彻底催化氧化,可见介孔碳修饰电极上的GOD保持了其生物学活性.     

核酸适配体封盖的介孔二氧化硅纳米颗粒用于肌红蛋白的检测

利用核酸适配体封盖的介孔二氧化硅纳米颗粒构建了一种新型、 简便及免标记的肌红蛋白定量检测方法. 首先, 用肌红蛋白核酸适配体将荧光小分子罗丹明6G封盖在介孔颗粒内, 当存在目标物肌红蛋白时, 由于介孔颗粒上的核酸适配体可特异性结合肌红蛋白而脱离介孔颗粒表面, 进而释放介孔颗粒内的罗丹明6G, 使溶液荧光强度增强. 实验结果表明, 荧光强度与肌红蛋白的浓度呈正相关, 通过荧光强度的变化可实现对肌红蛋白的定量检测. 该方法的检出限低至1.1 nmol/L, 且选择性好, 可满足临床医学的检测要求.     

甲壳胺-羧甲基纤维素钠高分子复合物固定酶的研究

本文采用天然高分子甲壳胺与羟甲基纤维素钠的高分子复合物作哉体,固定葡萄糖氧化酶和纤维素酶。得到的固定化酶活性较高、热稳定性好。固定化后的葡萄糖氧化酶比固定化前的最适反应温度提高50℃,固定化后的纤维素酶最适反应温度提高20℃。固定酶的贮存稳定性明显提高,并可反复使用。     

Mesoporous Silica Nanoparticles Functionalized with Amino Groups for Biomedical Applications

The synthesis and characterization of amino-functionalized mesoporous silica nanoparticles are presented following two different synthetic methods: co-condensation and post-synthesis grafting of 3-aminopropyltriethoxysilane. The amino groups’ distribution on the mesoporous silica nanoparticles was evaluated considering the aggregation state of a grafted photosensitizer (Verteporfin) by using spectroscopic techniques. The homogeneous distribution of amino groups within the silica network is a key factor to avoid aggregation during further organic functionalization and to optimize the performance of functionalized silica nanoparticles in biomedical applications. In addition, the formation of a protein corona on the external surface of both bare and amino-functionalized mesoporous silica was also investigated by adsorbing Bovine Serum Albumin (BSA) as a model protein. The adsorption of BSA was found to be favorable, reducing the aggregation phenomena for both bare and amino-modified nanoparticles. Nevertheless, the dispersant effect of BSA was much more evident in the case of amino-modified nanoparticles, which reached monodispersion after adsorption of the protein, thus suggesting that amino-modified nanoparticles can benefit from protein corona formation for preventing severe aggregation in biological media.     

单分散介孔氧化硅纳米颗粒的制备及其在生物材料方面的应用

单分散介孔氧化硅纳米颗粒由于其自身的优点,在当前许多领域有着广泛的应用前景。本文综述了近十几年来单分散介孔氧化硅纳米颗粒的制备方法以及在生物材料方面的应用。在制备方法方面,根据其制备机理分为稀溶液法、微乳法、模板剂法以及向反应体系中加入不同的添加剂等方法,制备出分散性好、不同形态、孔径尺寸可调的介孔氧化硅纳米颗粒。在生物材料的应用方面,主要介绍了其在药物与生物活性分子的负载与控制释放、生物大分子的固载与分离、生物标记与临床诊断等方面的应用。     

Electrochemical Behavior of Glucose Oxidase Immobilized on Pd‐Nanoparticles Decorated Ionic Liquid Derived Fibrillated Mesoporous Carbon

Pd nanoparticles with an average diameter of 5 nm were decorated on the surface of ionic liquid derived fibrillated mesoporous carbon (IFMC) to prepare a novel nano‐hybrid material (Pd@IFMC). Thereafter, glucose oxidase was immobilized on Pd@IFMC modified glassy carbon electrode to fabricate an enzymatic glucose biosensor. A pair of well‐defined redox peaks was recorded for direct electron transfer of the immobilized glucose oxidase at the formal potential of ? 0.418 V with a peak to peak separation of 25 mV. Electron transfer rate constant of was calculated to be 14.6 s^?1. The response of fabricated biosensor was linear towards glucose concentration.     

基于聚对苯二甲酸乙二醇酯薄膜的石墨烯/金纳米粒子/葡萄糖氧化酶柔性电极的制备及检测葡萄糖

采用化学气相沉积法生长多晶石墨烯(Graphene, G),转移至聚对苯二甲酸乙二醇酯(PET)薄膜表面,通过控制金溶胶蒸发速率,在多晶石墨烯表面组装均匀分布的亚单层金纳米粒子(AuNPs);然后修饰巯基乙酸,通过共价交联反应将葡萄糖氧化酶固定于AuNPs表面,构建基于PET膜的石墨烯/金纳米粒子/葡萄糖氧化酶(G/AuNPs/GOD)柔性电极.此电极在工作电位0.6 V(vs.SCE电极)、pH 7.0磷酸盐缓冲溶液、室温25℃条件下,差分脉冲伏安法响应电流与被测葡萄糖浓度在0.05~10.55 mmol/L范围内呈线性关系,线性方程为I(108A)=0.2629 C(mmol/L)+1.4149,线性相关系数 r=0.9955,检出限1 μmol/L (3σ). G/AuNPs/GOD柔性电极的制备可为特定环境和可穿戴设备的葡萄糖检测提供了新的途径和方法,拓展了葡萄糖检测的应用范围.     

Openwork@Dendritic Mesoporous Silica Nanoparticles for Lactate Depletion and Tumor Microenvironment Regulation

The direct depletion of lactate accumulated in the tumor microenvironment holds promise for cancer therapy but remains challenging. Herein, we report a one-pot synthesis of openwork@ dendritic mesoporous silica nanoparticles (ODMSNs) to address this problem. ODMSNs self-assembled through a time-resolved lamellar growth mechanism feature an openworked core and a dendritic shell, both constructed by silica nanosheets of ≈3 nm. With a large pore size, high surface area and pore volume, ODMSNs exhibited a high loading capacity (>0.7 g g⁻¹) of lactate oxidase (LOX) and enabled intratumoral lactate depletion by >99.9 %, leading to anti-angiogenesis, down-regulation of vascular endothelial growth factor, and increased tumor hypoxia. The latter event facilitates the activation of a co-delivered prodrug for enhancing anti-tumor and anti-metastasis efficacy. This study provides an innovative nano-delivery system and demonstrates the first example of direct lactate-depletion-enabled chemotherapy.     

Capped Mesoporous Silica Nanoparticles for the Selective and Sensitive Detection of Cyanide

The development of easy and affordable methods for the detection of cyanide is of great significance due to the high toxicity of this anion and the potential risks associated with its pollution. Herein, optical detection of cyanide in water has been achieved by using a hybrid organic–inorganic nanomaterial. Mesoporous silica nanoparticles were loaded with [Ru(bipy)₃]²⁺, functionalized with macrocyclic nickel(II) complex subunits, and capped with a sterically hindering anion (hexametaphosphate). Cyanide selectively induces demetallation of nickel(II) complexes and the removal of capping anions from the silica surface, allowing the release of the dye and the consequent increase in fluorescence intensity. The response of the capped nanoparticles in aqueous solution is highly selective and sensitive towards cyanide with a limit of detection of 2 μm .     

再生丝素固定葡萄糖氧化酶及其传感器应用

再生丝素固定葡萄糖氧化酶及其传感器应用钱江红，刘永成，刘海鹰，于同隐，邓家祺（复旦大学化学系高分子科学系，上海，２００４３３）关键词再生丝素，葡萄糖氧化酶，传感器，酶电极酶电报的各项性能在很大程度上取决于酶的固定比方法，葡萄糖氧化酶的固定化方法很多１...     

介孔SiO2负载的纳米金及其催化应用

金（Au）的催化作用已成为催化领域的前沿研究课题。本文综述了近年来采用不同方法制备介孔二氧化硅(MCM-41, MCM-48, SBA-15)负载的纳米Au催化剂以及在CO低温氧化、环己烯加氢和环己烷氧化等反应中的催化作用。讨论了影响纳米Au催化剂活性的相关因素, 包括载体的种类、表面性质、Au纳米颗粒的尺寸、分散度以及稳定性等。最后对各种制备纳米Au的方法进行了总结。     

Small Mesoporous Silica Nanoparticles as Carriers for Enhanced Photodynamic Therapy

Small mesoporous silica nanoparticles (MSNs; ca. 37 nm in diameter) have a high loading capacity for a hydrophobic photosensitizer, SiPcCl₂ (82.6 % in weight), and excellent endocytosis properties. As a result, the amount of SiPcCl₂ being delivered to cancer cells is increased by approximately two orders of magnitude compared to pure SiPcCl₂ at the same dosage, and the photodynamic therapy (PDT) efficiency is enhanced by over fourfold. Our method can be widely used to increase the dosage of hydrophobic anti‐cancer drugs in cancer cells and therefore increase the cytotoxicity of the drugs.