【摘要】：本論文以熒光金屬納米團簇和碳點為研究對象,利用生物礦化法、高溫熱解法等策略制備了多種金屬納米團簇、碳點及復(fù)合熒光納米傳感材料,考察其結(jié)構(gòu)、穩(wěn)定性、熒光傳感性能,發(fā)展了幾種光學(xué)探針用于有機小分子和重金屬離子的含量檢測方法,揭示探針與分析物的相互作用機理,實現(xiàn)多種痕量目標分析物的特異性敏感檢測,并探討其在實際環(huán)境中的應(yīng)用。本論文主要研究內(nèi)容如下:(1)基于銅納米團簇的曲酸生物傳感器:以蛋白包覆的銅納米團簇為熒光探針,以曲酸為檢測對象,通過穩(wěn)瞬態(tài)熒光光譜和紫外可見吸收光譜研究二者相互作用機制。研究結(jié)果表明,曲酸對銅納米團簇的熒光猝滅機制為靜態(tài)猝滅;銅納米團簇中銅元素呈現(xiàn)多價態(tài),曲酸與其中二價銅離子發(fā)生特異性反應(yīng)生成曲酸銅沉淀,進而使銅納米簇熒光猝滅。基于該作用機制,在最佳檢測條件下,建立曲酸的熒光分析法。(2)基于金納米團簇的熒光和共振光散射雙模式檢測植酸:采用溶菌酶為模板制備的金納米團簇作為熒光和共振光散射探針,以植酸為檢測對象,重點研究溶菌酶包覆金納米團簇與植酸相互作用后共振光散射光譜和熒光光譜變化,分析植酸對溶菌酶包覆金納米團簇粒徑分布和形貌的影響機制,剖析二者相互作用機理。結(jié)果表明,植酸可以誘導(dǎo)生成包含有多個單分散金納米簇的聚集體結(jié)構(gòu),從而引起了熒光的猝滅和共振光散射信號的顯著增強。(3)碳點熒光“關(guān)-開”模式檢測植酸:以檸檬酸和賴氨酸為原料制備熒光碳點,考察碳點、碳點/鐵離子和碳點/鐵離子/植酸體系的穩(wěn)瞬態(tài)熒光光譜性質(zhì)變化,構(gòu)建基于碳點熒光“關(guān)—開”模式的植酸檢測方法,并考察方法的穩(wěn)定性、特異性、檢測范圍和檢測限。綜合Zeta電位、熒光衰減和共振光散射多種分析手段對熒光恢復(fù)機理進行分析。研究結(jié)果表明,植酸與碳點競爭結(jié)合鐵離子,通過抑制碳點與鐵離子之間的光誘導(dǎo)電子轉(zhuǎn)移過程,實現(xiàn)熒光恢復(fù)。(4)雙發(fā)射比率型熒光傳感體系:制備碳點摻雜的二氧化硅粒子與蛋白質(zhì)穩(wěn)定的金納米團簇,通過化學(xué)交聯(lián)兩種熒光納米材料,形成單一激發(fā)波長下可發(fā)射雙熒光的復(fù)合納米粒子,并將其發(fā)展為Hg~(2+)濃度測定的比率型熒光探針;進一步,將雙發(fā)射比率型熒光探針與分子印跡技術(shù)相結(jié)合,在雙發(fā)射納米粒子表面生長印跡層,構(gòu)建分子印跡比率型熒光探針,并將其應(yīng)用于環(huán)境污染物對硝基苯酚的選擇性測定。
[Abstract]:In this paper, a variety of metal nanoclusters, carbon points and composite fluorescent nanosensors were prepared by biomineralization and pyrolysis, and their structures and stability were investigated. Fluorescence sensing properties. Several optical probes have been developed for the detection of organic small molecules and heavy metal ions. The mechanism of interaction between the probes and the analytes has been revealed, and the specific sensitive detection of trace target analytes has been realized. Its application in practical environment is also discussed. The main contents of this thesis are as follows: (1) kojic acid biosensor based on copper nanoclusters: protein coated copper nanoclusters are used as fluorescent probes, and kojic acid is used as the detection object. The mechanism of interaction between the two was studied by steady transient fluorescence spectroscopy and UV-Vis absorption spectra. The results showed that the fluorescence quenching mechanism of kojic acid on copper nanoclusters was static quenching. Furthermore, the fluorescence quenching of copper nanoclusters was observed. Based on this mechanism, under the best detection conditions, Fluorescence analysis of kojic acid was established. (2) phytic acid was detected based on fluorescence and resonance light scattering (RLS) of gold nanoclusters: gold nanoclusters prepared by lysozyme were used as fluorescence and resonance light scattering probes, phytic acid was used as the detection object. The changes of resonance light scattering (RLS) spectra and fluorescence spectra after the interaction of lysozyme coated gold nanoclusters with phytic acid were studied. The mechanism of phytic acid affecting the particle size distribution and morphology of lysozyme coated gold nanoclusters was analyzed. The results show that phytic acid can induce the formation of aggregates containing a number of monodisperse gold nanoclusters. The quenching of fluorescence and the enhancement of resonance light scattering signal were induced. (3) carbon spot fluorescence "off on" mode was used to detect phytic acid: fluorescent carbon points were prepared from citric acid and lysine, and carbon points were investigated. The stable transient fluorescence spectra of carbon spot / iron ion and carbon point / iron ion / phytic acid system were changed. A method of phytic acid detection based on the "on-off" mode of carbon spot fluorescence was constructed, and the stability, specificity, detection range and detection limit of the method were investigated. The mechanism of fluorescence recovery was analyzed by Zeta potential, fluorescence attenuation and resonance light scattering. The results show that phytic acid competes with carbon point to bind iron ion, which inhibits the photoinduced electron transfer process between carbon point and iron ion. (4) double emission ratio fluorescence sensing system: carbon dot-doped silica particles and protein stable gold nanoclusters were prepared by chemical crosslinking of two kinds of fluorescent nanomaterials. The composite nanoparticles which can emit double fluorescence at a single excitation wavelength were formed and developed into a ratio fluorescent probe for the determination of Hg~ (2) concentration. Further, the double emission ratio fluorescence probe was combined with molecular imprinting technique. A molecularly imprinted ratio fluorescent probe was constructed on the surface of double emission nanoparticles and applied to the selective determination of p-nitrophenol, an environmental pollutant.
【學(xué)位授予單位】：天津大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2015
【分類號】：O657.3;TB383.1
，

本文編號：2232449