由于纳米科技的迅猛发展，纳米材料与医学的联系越来越紧密，纳米材料凭借其特殊的表面效应、体积效应及量子尺寸效应等，迅速成为了研究热点，在荧光分子成像和医疗诊断应用等方面呈现出强大的后劲。虽然量子点(QDs)之类的荧光纳米材料具有强荧光，很高的光化学稳定性和出色的抗化学降解性等诸多特殊优势。但是，大部荧光材料成分上具有毒性，生物相容性差，对肿瘤进行诊断成像的同时，对其它正常组织也造成了严重的伤害。

金纳米簇是近年来比较热门的一种新型荧光纳米材料，除了具有强荧光，毒性小，抗光漂白等优点外，还因为拥有奇特的光学性能，在成像、传感等方面也有着十分广阔的运用前景。目前金簇的一些合成方法中，以牛血清蛋白作为还原剂和保护价剂来合成金簇用于肿瘤细胞成像是最为经典的方法，但牛血清蛋白质属于天然抗原，是一种异源药用蛋白质，在进入人体后会诱发抗体抗原反应而被清除，引起免疫原性，甚至会导致过敏反应。

在这项工作中，我们将金纳米簇作为研究对象，采用水浴机械搅拌、超声法作为合成金簇的手段，针对近红外分子成像应用中的要求发展了新的制备金簇的方法，并对影响金簇粒径、荧光强度等因素进行分析，充分优化实验条件，合成适用于要求的新材料，并初步预想将其用于近红外成像的探索。此项研究除了对癌症进行早期诊断、治疗和预防，减少癌症死亡率，保障人类健康具有重大意义以外，它还具有促进分子影像和医学诊断发展的作用。

本论文研究工作主要包括以下内容:

1. 归纳全部文献中关于牛血清蛋白合成金簇的方法，水浴加热，磁力搅拌下，使用人血清白蛋白(HSA)作为还原剂和保护剂来消除人体的免疫原型，成功制备出金簇。通过对不同合成方法的实验条件进行对比，找到了影响金簇荧光强度，粒径，量子产率的关键影响因素。另外，首次尝试引入超声作为促进化学反应的手段，将其运用于金纳米簇的合成中在短时间内成功制备出了具有近红外发射荧光的金簇，通过对工艺条件的调控，提出了可靠的优化方案。

2.利用荧光光谱、紫外吸收光谱、高分辨率透射电镜、动态光散射、红外光谱等技术对优化工艺后制备出的金簇进行表征，制备出的金簇粒径均小于2 nm，尺寸均一且分布均匀，这种比生物分子还要小的尺寸，更有利于金簇进入更深的组织内部，达到良好的成像效果；金簇量子产率分别为11%和9%，具有良好的荧光特性，荧光强度高，最大发射峰接近于近红外波段，极大地降低了可见光区成像的问题；在一些模拟人体环境中比较稳定，具有潜在的分子成像运用前景。

关键词：纳米材料，荧光，人血清白蛋白，水热，超声，近红外成像

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