几种MOFs吸附性能的压电监测及其在生物传感分析中的应用

发布时间：2018-03-09 01:39

本文选题：金属有机骨架　切入点：石英晶体微天平　出处：《山东师范大学》2017年博士论文　论文类型：学位论文

【摘要】：金属有机骨架(MOFs)材料是一类新型多孔晶体材料,具有超高的比表面积,而且结构呈现多样性和可裁剪性,晶体中孔径大小可调,在催化、气体的储存与分离、药物传输、化学传感器等领域显示了良好的应用前景。本论文以几种常见的MOFs为模型,以石英晶体微天平为检测手段,研究了碘在MOFs膜的吸附动力学过程,基于MOFs的分子筛和催化作用设计了高效H_2O_2光电传感器,以及以MOFs作为标记物用于免疫分析。主要研究内容如下:1.联用压电传感与分光光度法监测碘在MOFs膜上的吸附动力学过程本章建立了一种联用压电传感器与分光光度法监测了碘在MIL-101和ZIF-67两种MOFs膜中吸附动力学过程的方法。鉴于I_2蒸气损伤石英晶体微天平中的激励电极,采用了分离电极式的传感器设计。以压电传感器和光度法分别监测吸附量、气相中I_2的浓度的动态变化曲线。结果表明,ZIF-67对I_2的吸附容量(4.41 g/g)远高于MIL-101(0.58 g/g),在ZIF-67中的结构单元2-甲基咪唑对吸附I_2起着主要的作用,其吸附容量达3.15 g/g。MIL-101吸附I_2的等温线符合Henry定律。由于I_2蒸气在ZIF-67的微孔中存在毛细凝结,I_2在ZIF-67膜上的吸附等温线呈抛物线形,即随I_2蒸气浓度的增加而吸附量增幅变大。根据吸附动力学数据,测定I_2在MIL-101和ZIF-67膜上的扩散系数分别为6.1×10~(-16)和3.7×10-16 m~2/min。利用浓度-时间曲线,所建立的分析方法可以解析出包括可逆、不可逆吸附状态的动力学参数。2.基于MOFs膜分子筛和催化效应的H_2O_2光电流型传感器本章提出了一种提高H_2O_2光电流型(PEC)传感器的灵敏度和选择性策略。以二氧化钛纳米管阵列(TiO_2 NTs)为基底,修饰石墨相氮化碳(g-C_3N_4)与碳纳米管(CNTs)复合物,构成光敏电极g-C_3N_4-CNTs/TiO_2 NTs,再通过液相生长法在其表面膜上形成Cu-MOFs[Cu_3(BTC)_2],该MOFs膜层具有分子筛的作用,能够阻止比其孔径大的分子扩散超越膜层而允许较小分子的通过,这样能提高PEC传感器对较小分子(例如H_2O_2)的选择性,而Cu_3(BTC)_2对H_2O_2在PEC反应有催化作用,能显著提高PEC传感器对H_2O_2的灵敏度,增敏因子达到10倍。试验了碳纳米管用量与厚度对PEC传感器响应性能的影响。在优化的实验条件下,所制备的Cu_3(BTC)_2/g-C_3N_4-CNTs/TiO_2NTs传感器应用于H_2O_2的检测,检测限为1.1 nmol/L,能大大降低来自较大分子(例如抗坏血酸、尿酸和多巴胺等)的干扰。3.MOFs作为信号标记物用于电化学免疫分析两个肿瘤标志物通过简便的化学方法制备出性质稳定和高度分散的聚苯胺纳米纤维(PANI),并用于化学修饰玻碳电极(GCE),将PANI的良好导电性与巯基丙酸(MSA)对金属离子的高度络合能力相结合,制备出Nafion/MSA/PANI/GCE修饰电极,可用于同时检测Cd~(2+)和Pb~(2+),检测限分别为0.05μg/L Cd~(2+)和0.2μg/L Pb~(2+)。将制备的Cd-MOFs和Pb-MOFs分别用于标记肿瘤标志物甲胎蛋白(AFP)和癌胚抗原(CEA),将所得夹心结构免疫配合物中的MOFs以酸溶解,用所制备的修饰电极检测其中的Cd~(2+)和Pb~(2+),同时测定这两种肿瘤标志物,检测限分别为0.1 pg/mL(AFP)和0.03 pg/m L(CEA),所制备的高性能修饰电极和相关分析方法在免疫分析中具有良好的应用前景。4.基于生物金属化与双重信号放大的压电免疫传感器阵列提出了一种基于压电免疫传感器阵列的差分测量模式,可明显抑制了来自于非质量效应,包括溶液电导率、粘度、密度、温度的波动对压电传感器的信号的影响,比较了基频、3倍频、5倍频的差分响应特性。在氨基化的压电传感器阵列上固定免疫探针,待完成目标抗原的识别反应后,再与碱性磷酸酶(ALP)标记的二抗结合形成夹心式免疫配合物,利用其中的ALP催化底物对-氨基苯磷酸酯(p-APP)水解产生还原剂将Pd(Ⅱ)还原为Pd核,并以此为催化剂,进行化学镀Ni-P的双重信号放大,增加压电免疫传感器的响应灵敏度。将提出的方法应用于人免疫球蛋白(hIgG)的检测,检测限为1 pg/m L,和仅沉积Pd核的生物金属化相比,Ni-P沉积二次信号放大提高压电免疫传感器的灵敏度近三个数量级,得益于Ni-P反应的高活化能和差分测量模式的低基线漂移。
[Abstract]:Metal organic frameworks (MOFs) material is a new type of porous crystalline materials with high specific surface area and structure diversity and can be cut, the pore size of the crystal is adjustable in catalysis, gas storage and separation, drug delivery, chemical sensors show a good application prospect. Based on several common MOFs models, using quartz crystal microbalance method of iodine adsorption kinetics in MOFs membrane, MOFs molecular sieve and catalytic effect based on the design of efficient H_2O_2 photoelectric sensor, and using MOFs as a marker for immune analysis. The main contents are as follows: 1. by combining the piezoelectric sensing and spectrophotometric monitoring of iodine on MOFs membrane adsorption kinetics this chapter established a combination of piezoelectric sensor and spectrophotometric monitoring of iodine in MIL-101 and ZIF-67 two MOFs membrane adsorption kinetics. The method of I_2 vapor damage. Given the excitation electrode of quartz crystal microbalance sensor is designed by the separation electrode. With piezoelectric sensors and spectrophotometry respectively for monitoring adsorption capacity, dynamic change curve of I_2 concentration in the gas phase. The results show that the adsorption capacity of ZIF-67 I_2 (4.41 g/g) is much higher than the MIL-101 (0.58 g/g), structural unit of 2- methyl imidazole in ZIF-67 plays an important role in the adsorption isotherms of I_2, the adsorption capacity of 3.15 g/g.MIL-101 adsorption of I_2 conforms to the Henry law. Because of the existence of capillary condensation in ZIF-67 microporous I_2 vapor, adsorption isotherms of I_2 on ZIF-67 film with a parabola the increase of I_2 concentration and vapor adsorption amount increased more. According to the data of the adsorption kinetics, the determination of I_2 in MIL-101 and ZIF-67 on the membrane diffusion coefficient was 6.1 * 10~ (-16) and 3.7 * 10-16 m~2/min. with the concentration - time curve, the The established method can resolve including reversible and irreversible adsorption kinetic parameters of.2. based on the H_2O_2 optical current sensor MOFs molecular sieve membrane and catalytic effect of this chapter proposes a improved H_2O_2 optical current type (PEC). The sensitivity and selectivity of sensor strategy taking TiO2Nanotube array (TiO_2 NTs) as substrate. Modified graphite carbon nitride (g-C_3N_4) and carbon nanotubes (CNTs) composites, a photosensitive electrode of g-C_3N_4-CNTs/TiO_2 NTs, and then through the liquid phase growth method to form Cu-MOFs[Cu_3 in the film (BTC) _2], the MOFs film with a molecular sieve, can prevent molecules than the large aperture of the diffusion layer and allow the beyond small molecules, which can improve the PEC sensor of smaller molecules (e.g. H_2O_2) selectivity, and Cu_3 (BTC) _2 on H_2O_2 catalyst in the PEC reaction, can significantly improve the PEC sensor on H The sensitivity of _2O_2 enhancement factor reaches 10 times. The test of the amount of carbon nanotube and thickness effect on the response performance of the PEC sensor. Under the optimized experimental conditions, the prepared Cu_3 (BTC) _2/g-C_3N_4-CNTs/TiO_2NTs detection sensor applied to H_2O_2, the detection limit is 1.1 nmol/L, can greatly reduce from larger molecules (such as ascorbic acid uric acid and dopamine), the interference of.3.MOFs as signal marker for electrochemical immunoassay of two tumor markers by a simple chemical method for preparing a stable and highly dispersed polyaniline nano fiber (PANI), and used for chemical modification of glassy carbon electrode (GCE), PANI good conductivity and mercaptopropionic acid (MSA) high complexing ability of metal ions on the combination of the preparation of Nafion/MSA/PANI/GCE modified electrode can be used for the simultaneous detection of Cd~ (2+) and Pb~ (2+), the detection limits were 0.05 g/L and 0 Cd~ (2+) .2 g/L Pb~ (2+). The preparation of Cd-MOFs and Pb-MOFs were used to label tumor marker alpha fetoprotein (AFP) and carcinoembryonic antigen (CEA), the sandwich structure of immune complexes of MOFs in acid solution with Cd~, the modified electrode for the detection of the prepared (2+) and Pb~ (2+), the simultaneous determination of two kinds of tumor markers, the detection limits were 0.1 pg/mL and 0.03 pg/m (AFP) L (CEA), the high performance modified electrode preparation and correlation analysis method in immunoassay has good application prospect of.4. piezoelectric immunosensor array bio metal and dual signal a measurement based on amplification mode piezoelectric immunosensor array is presented based on the difference, can be inhibited from non mass effect, including conductivity, viscosity, density, effect of temperature fluctuation on the piezoelectric sensor signal, comparing the frequency, frequency 3, 5 frequency differential responses In the piezoelectric sensor array. The amino fixed on the immuno probe, to complete the target antigen recognition reaction, and alkaline phosphatase (ALP) labeled two antibody binding form sandwich immune complexes, phosphate benzene with ALP catalyzed by the amino (p-APP) hydrolyzed reducing agent (Pd II) reduction of nuclear Pd, and as a catalyst for electroless plating of Ni-P dual signal amplification, increase the sensitivity of piezoelectric immunosensor. The proposed method is applied to the Human Immunoglobulin (hIgG) detection, the detection limit is 1 pg/m L, compared with the biological metal deposit only Pd core, two Ni-P deposition signal amplification to improve the sensitivity of piezoelectric immunosensor for nearly three orders of magnitude, thanks to the Ni-P response of the high activation energy and a differential measurement mode with low baseline drift.

【学位授予单位】：山东师范大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：O647.3;TP212

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