中文摘要：

合成了巯基乙酸（TGA）修饰的量子点,X衍射分析证实CdTe相的存在,高分辨电子显微镜分析表明量子点的直径为3 nm,Zeta电位表征表明量子点表面带有负电荷.把TGA修饰的CdTe量子点加入到聚合酶链反应（PCR）反应液中,使用brcaa1基因载体作为PCR反应的模板,进行两轮PCR反应.最终的PCR产物通过w=1%的琼脂糖凝胶电泳进行分析,结果表明,在0-1.33 g/L范围内,随着量子点的量逐渐增加,非特异性的扩增条带逐渐消失,荧光（PL）光谱表明PCR反应后的量子点荧光强度降低.X射线光电子能谱（XPS）证实PCR反应前后Cd元素和Te元素的能谱峰并没有出现化学位移,吸收光谱（UV-vis）表明了PCR反应之后的吸收强度增强.因此,TGA修饰的CdTe量子点置于PCR反应液之中,能提高PCR的特异性,可以应用于超灵敏DNA检测、光电生物传感器.

英文摘要：

The effects of mercaptoacetic acid （TGA） modified CdTe quantum dots on the specificity of polymerase chain reaction （PCR） were explored. TGA modified CdTe quantum dots were synthesized. XRD analysis shows that cubic CdTe QDs are formed. TGA modified CdTe QDs were synthesized with the diameter of 3nm from HR-TEM observation and surface negative charge. TGA modified CdTe quantum dots were added into PCR liquids, brcaal gene vector was used as PCR template, two-round PCRs were done. The final PCR products were analyzed by 1% agarose gel electrophoresis. 1% agarose gel electrophoresis analysis shows that below the concentration of 1.33 mg/ml CdTe QDs, as the amounts of QDs increase in the PCR liquids, the non-specific amplification bands gradually disappear. PL shows that photoluminesence （PI.） intensity of PCR liquids after PCR is lower than that before PCR. XPS shows that no element position shift is observed. UV-vis spectroscopy analysis shows that UV-vis absorption spectra after PCR is higher than that before PCR. TGA modified CdTe quantum dots in PCR liquids can markedly improve PCR specificity. The phenomena owns potential in application such as ultra-sensitive DNA detection, photoelectric biosensors.