溴化乙锭标记DNA电化学探针的研究

以乙基-(3-二甲基丙基)碳化二亚胺盐酸盐(EDC)为偶联活化剂,将电化学活性物质溴化乙锭(Ethidiumbromide,EB)成功地标记在人工合成的含有21个碱基的寡聚DNA片段上,制备成EB标记DNA探针;用电化学方法将待测样品DNA片段固定在石墨电极表面,在一定的温度、pH值和离子强度条件下与EB标记DNA探针进行杂交反应,从而对靶序列DNA片段进行识别和测定.此外,还讨论了该探针的电化学性质、荧光光谱、待测DNA片段在石墨电极表面的电化学固定、DNA链碱基长度对EB标记DNA电化学探针的影响以及探针的选择性、重现性和寿命,结果令人满意.

Studies on the Preparation and Characterization of Ethidium Bromide Labeled DNA Probe

The preparation and characterization of an ethidium bromide labeled DNAprobe is studied. Ethidium bromide was labeled onto a 21-bases 5'-oligonucleotides by EDC. The electrochemical characterization and fluorescence of the probe is discussed. The accumulation of sample DNAis also discussed. Besides it, the effect of base amounts on labeling and hybridization were discussed. We think the bases between 15-200 are better for electrochemical labeled DNAprobe. The EBlabeled DNAprobe was successfully used to detect sequence specific DNA. It shows a high sensitivity and selectivity. It is hoped for commodity use.