【摘要】：熒光光譜技術(shù)被廣泛應(yīng)用于醫(yī)學(xué)診斷、生物成像以及物質(zhì)分析等領(lǐng)域,其檢測(cè)極限取決于熒光信號(hào)的信背比。將熒光分子放置于特定構(gòu)型的金屬納米結(jié)構(gòu)附近,利用入射光場(chǎng)、金屬納米結(jié)構(gòu)和熒光分子三者之間的相互作用對(duì)分子的熒光激發(fā)和發(fā)射過(guò)程進(jìn)行調(diào)控,能夠有效增加熒光信號(hào)強(qiáng)度,進(jìn)而提高檢測(cè)靈敏度。本論文利用金和金銀核殼納米棒溶膠為增強(qiáng)襯底,系統(tǒng)研究了單光子激發(fā)條件下金屬納米顆粒的局域表面等離激元共振模式與熒光分子發(fā)射光譜之間的耦合程度對(duì)熒光增強(qiáng)效應(yīng)的影響規(guī)律；并對(duì)金屬增強(qiáng)多環(huán)芳烴類(lèi)化合物蒽的雙光子激發(fā)熒光特性做了初步探索。論文主要工作包括以下四個(gè)部分：1.系統(tǒng)地介紹了金屬納米顆粒局域表面等離激元的產(chǎn)生和特性,以及基于表面等離激元的重要應(yīng)用-表面增強(qiáng)熒光效應(yīng)的產(chǎn)生機(jī)理和襯底分類(lèi)。2.采用種子生長(zhǎng)法合成金納米棒溶膠；在此基礎(chǔ)上,制備金銀核殼納米棒。通過(guò)調(diào)控反應(yīng)過(guò)程中試劑的使用量,制備得到具有不同局域表面等離激元共振波長(zhǎng)的金和金銀核殼納米棒。3.實(shí)驗(yàn)上選取具有不同局域表面等離激元共振波長(zhǎng)的金和金銀核殼納米棒溶膠為增強(qiáng)襯底,基于激光光譜學(xué)方法,研究了金屬納米棒對(duì)VA嗪720分子的表面增強(qiáng)單光子激發(fā)熒光效應(yīng)。研究表明,隨著分子-金屬納米棒混合體系中納米棒濃度的增加,熒光增強(qiáng)程度呈現(xiàn)先增大后減小的趨勢(shì),這歸因于分子輻射衰減速率增加引起的熒光強(qiáng)度增大和自過(guò)濾效應(yīng)帶來(lái)的熒光強(qiáng)度減弱之間的競(jìng)爭(zhēng)；通過(guò)進(jìn)一步分析不同襯底的增強(qiáng)熒光效應(yīng)發(fā)現(xiàn),在考慮分子激發(fā)效率不受影響的情況下,金屬納米顆粒等離激元共振模式與熒光分子發(fā)射光譜之間的耦合程度對(duì)增強(qiáng)效果的影響強(qiáng)烈依賴(lài)于混合體系中金屬納米顆粒的濃度。在濃度較低時(shí),具有最大耦合程度的金屬納米棒表現(xiàn)出最佳的熒光增強(qiáng)效果；而當(dāng)濃度增加到一定量時(shí),受到自過(guò)濾效應(yīng)的影響,具有最大耦合程度的金屬納米棒反而有可能產(chǎn)生最弱的熒光增強(qiáng)。4.研究了金納米棒對(duì)多環(huán)芳烴類(lèi)化合物蒽的雙光子激發(fā)熒光增強(qiáng)效應(yīng)。利用相轉(zhuǎn)移手段和緩慢揮發(fā)溶劑的方法制備得到蒽-金納米棒混合體系,研究表明,由于金納米棒在光場(chǎng)激發(fā)下對(duì)分子激發(fā)和發(fā)射行為的調(diào)控,蒽的雙光子激發(fā)熒光信號(hào)明顯增強(qiáng)。
[Abstract]:Fluorescence spectroscopy is widely used in medical diagnosis, biological imaging and material analysis, and its detection limit depends on the signal-to-back ratio of fluorescence signals. The fluorescence molecules are placed near the metal nanostructures of a specific configuration. The fluorescence excitation and emission processes of the molecules are regulated by the interaction among incident light field, metal nanostructures and fluorescent molecules. It can effectively increase the intensity of fluorescence signal, and then improve the detection sensitivity. In this thesis, gold and silver core-shell nanorods were used as reinforcing substrates. The influence of the coupling degree between the local surface plasmon resonance mode and the fluorescence emission spectrum on the fluorescence enhancement effect of metal nanoparticles under single photon excitation is studied systematically. The two-photon excited fluorescence properties of anthracene, a metal-enhanced polycyclic aromatic compound, were also studied. The main work of this paper consists of the following four parts: 1. In this paper, the generation and characteristics of the local surface plasmon of metal nanoparticles, the generation mechanism of the surface enhanced fluorescence effect and the substrate classification based on the surface isoplasmon are systematically introduced in this paper, as well as the generation mechanism and substrate classification of the surface enhanced fluorescence effect based on the surface plasmon. Gold nanorods were synthesized by seed growth method and gold-silver core-shell nanorods were prepared. Gold and gold-silver core-shell nanorods with different local surface plasmon resonance wavelengths were prepared by adjusting the amount of reagents used in the reaction. Gold and gold-silver core-shell nanorods with different local surface plasmon resonance wavelengths were selected as enhanced substrates based on laser spectroscopy. The surface-enhanced single-photon excitation fluorescence effect of metal nanorods on the VA pyrazine 720 molecule was studied. The results show that the fluorescence enhancement increases first and then decreases with the increase of the concentration of nanorods in molecular-metal nanorods. This is due to the competition between the increase of fluorescence intensity caused by the increase of molecular radiation attenuation rate and the decrease of fluorescence intensity caused by self-filtration effect. By further analyzing the enhanced fluorescence effect of different substrates, it is found that the molecular excitation efficiency is not affected by the molecular excitation efficiency. The coupling between the plasmon resonance mode of metal nanoparticles and the emission spectra of fluorescent molecules strongly depends on the concentration of metal nanoparticles in the mixed system. When the concentration is low, the metal nanorods with the maximum coupling degree show the best fluorescence enhancement effect. However, when the concentration increases to a certain amount, the metal nanorods with the maximum coupling degree may produce the weakest fluorescence enhancement due to the influence of the self-filtration effect. 4. The two-photon excitation fluorescence enhancement effect of gold nanorods on anthracene was studied. Anthracene-gold nanorods were prepared by phase transfer method and slowly volatile solvent method. The results showed that gold nanorods could regulate the molecular excitation and emission behavior under light field excitation. The fluorescence signal of anthracene excited by two-photon was enhanced obviously.
【學(xué)位授予單位】：陜西師范大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類(lèi)號(hào)】：TB383.1;O657.3

【共引文獻(xiàn)】

相關(guān)期刊論文 前10條

1 曾偉成,黃穎,樊希承;植物凝集素穩(wěn)定性的熒光光譜分析[J];海峽藥學(xué);2005年02期

2 曾偉成;黃穎;樊希承;陳勇攀;;FDA-EB雙色熒光分析法檢測(cè)細(xì)胞活性的變化[J];海峽藥學(xué);2007年01期

3 佘家Y，

本文編號(hào)：2449839