本文選題：CdSe量子點　切入點：溫度調控合成　出處：《中南大學》2012年碩士論文　論文類型：學位論文

【摘要】：研究生物分子間的相互作用以及對重大疾病的早期診斷,迫切需要在微觀尺度上原位、活體、實時地獲取各種生物化學信息,因此制備具有生物相容性,熒光性能強、小尺寸的熒光材料具有重要應用價值。量子點以其優(yōu)異的光學特性如吸收光譜連續(xù),發(fā)射光譜依粒子尺寸變化可調,熒光量子產率高和耐光漂白等特點在生物醫(yī)學領域如生物分子的標記和檢測,細胞標記/成像,活體成像,腫瘤的診斷和治療等領域展現(xiàn)了廣泛的應用前景。然而制備尺寸均一、熒光性能穩(wěn)定,具有生物相容性的量子點已經成為其生物醫(yī)學應用領域的重大挑戰(zhàn)。本論文研究了液體石蠟體系中通過溫度調控的簡易制備尺寸分布均一CdSe量子點的方法。通過以液體石蠟為溶劑,油酸為表面包覆有機基團,合成CdSe量子點。研究制備過程中反應時間、反應溫度和前驅體等因素對制備CdSe量子點結晶性、粒徑分布和熒光發(fā)射光譜等性能的影響規(guī)律；利用電子透射顯微鏡(TEM),高分辨電子透射顯微鏡(HRTEM),選擇區(qū)域衍射(SEAD), X射線衍射(XRD),熒光光譜(PL)及紫外可見吸收光譜(UV-VIS)表征制備CdSe量子點形貌量子點尺寸晶體結構及熒光紫外性能。實驗表明液體石蠟體系中生長溫度(T)與CdSe量子點尺寸(d)存在線性相關性d=0.0207T-0.7068,各生長溫度下量子點粒徑分別為：140℃為2.3nm,180℃為3nm,210℃為3.3nm,240℃為4.5nm。熱力學基本原理計算液體石蠟體系中溫度調控時ΔG0,促使粒徑生長；當油酸比例從(OA:CdO=4:1)升至(OA:CdO=10:1)時,有機基團的過量吸附會導致樣品缺陷發(fā)光的增加,從而熒光下降；而過低(OA:CdO=3:1)會使得制備Cd前驅體困難,造成大量沉淀的產生,合成溫度從140℃上升至180℃,210℃或240℃時,有利于CdSe量子點結晶并提高熒光性能；利用巰基丙酸(MPA)修飾CdSe量子點后暴露果蠅,閃鋅礦結構的CdSe量子點水溶液分散后尺寸分布均勻,水合動力學尺寸為30nm；利用熒光倒置顯微鏡觀測CdSe量子點在果蠅體內分布狀況,發(fā)現(xiàn)CdSe量子點成功進入果蠅體內且主要分布在腸道位置。
[Abstract]:In order to study the interaction between biomolecules and the early diagnosis of major diseases, there is an urgent need to obtain biochemistry information in situ, in vivo and in real time at the micro scale. Therefore, the preparation has biocompatibility and strong fluorescence performance. Small size fluorescent materials have important application value. Quantum dots have excellent optical properties such as continuous absorption spectra, and the emission spectra can be adjusted according to particle size. The characteristics of high fluorescence quantum yield and photobleaching resistance in biomedical fields such as biomolecules labeling and detection, cell labeling / imaging, in vivo imaging, The diagnosis and treatment of tumors have shown a wide range of applications. However, the size of the preparation is uniform, and the fluorescence performance is stable. Biocompatible quantum dots (QDs) have become a major challenge in biomedical applications. In this paper, a simple method of preparing uniform CdSe quantum dots with uniform size distribution by temperature control in liquid paraffin system has been studied. Using liquid paraffin as solvent, The effects of reaction time, reaction temperature and precursor on the crystallinity, particle size distribution and fluorescence emission spectra of CdSe quantum dots were studied. CdSe quantum dots were characterized by electron transmission microscope (TEM), high resolution electron transmission microscope (HRTEM), selective region diffraction (SEAD), X-ray diffraction (XRD), fluorescence spectrum (PL) and UV-VIS (UV-VIS). The experimental results show that there is a linear correlation between the growth temperature (T) and the size of CdSe quantum dots (d) in liquid paraffin system. The particle size of quantum dots at each growth temperature is 1: 140 鈩，

本文編號：1625305