中文摘要以含不同数量胞嘧啶(C)碱基茎−环结构(stem-loop hairpin)序列特定的单链寡聚核苷酸(ssDNA)、硼氢化钠(NaBH4)、硝酸银(AgNO3)和乙酸铵([CH3COO−][NH4+])为原料合成了ssDNA保护的银纳米团簇(Ag nanoclusters,简称AgNCs,AgNCs@DNA),对AgNCs@DNA进行了紫外−可见吸收光谱、光致发光(荧光)光谱(PL)及电致发光光谱(ECL)等光谱表征和测量。结果证明了AgNCs@DNA的荧光光谱有两个发射峰,且发射峰位置随着DNA序列中C碱基的个数与静置时间而改变,发光强度也会变化,但是电致发光现象不明显。继而探讨了AgNCs@DNA对CdS量子点(CdS QDs)的激子态发光行为的影响,结果显示加入AgNCs@DNA后,CdS QDs的PL和ECL强度都有大幅下降,证实了AgNCs@DNA对CdS QDs的高效的猝灭效应。63857
关键词DNA;银纳米团簇;量子点;荧光;电致发光;猝灭
Abstract Deoxyribonucleic acid-protected silver nanoclusters (AgNCs@DNA) was successfully synthesized with single-stranded hairpin oligo-nucleotide (ssDNA) containing a cytosine (C)-rich loop, sodium borohydride (NaBH4), silver nitrate (AgNO3) and ammonium acetate ([CH3COO−][NH4+]). The optical properties of as-prepared AgNCs@DNA were characterized and analyzed by UV-Vis absorption, photoluminescence (PL) and electrochemiluminescence (ECL) spectra. The PL spectrum of AgNCs@DNA showed two emission peaks whose positions as well as intensities varied with the amount of C bases and storing duration. However, the ECL behavior of AgNCs@DNA was unwitnessed. The influences of AgNCs@DNA on the excitonic luminescent behavior of CdS QDs were further investigated. Great decline in both PL and ECL intensities of CdS QDs aqueous solution were observed after AgNCs@DNA was introduced into, demonstrating a highly PL plus ECL quenching efficiency of AgNCs@DNA upon CdS QDs.
Keywords DNA; Silver nanocluster; Quantum dot; Photoluminescence; Electrochemiluminescence; Quenching
目录
中文摘要 03
Abstract 04
第一章 绪论 05
1.1纳米团簇简介 05
1.2 DNA纳米技术 06
1.3光致发光 08
1.4电致发光 08
1.5猝灭效应 09
第二章 DNA保护银纳米团簇的合成及其光/电致发光性质的研究 11
2.1实验材料 11
2.1.1实验试剂 11
2.1.2实验仪器和设备 11
2.2实验方法和步骤 11
2.2.1 AgNCs@DNA的合成 11
2.2.2 AgNCs@DNA的光谱表征 12
2.2.3 AgNCs@DNA的ECL行为 13
2.2.4 AgNCs@DNA对CdS QDs的猝灭效应 14
2.2.5注意事项 15
2.3实验结果和分析讨论 15
2.3.1 AgNCs@DNA和CdS QDs的紫外光谱图 15
2.3.2 AgNCs@DNA的荧光光谱图 16
2.3.3 AgNCs@DNA的ECL光谱图 18
2.3.4 AgNCs@DNA对CdS QDs的猝灭效应 18
2.4结论 21
致谢 22
参考文献 23 第一章 绪论
1.1纳米团簇简介