纳米金增效微重量法核酸检测的研究

Development of Microgravimetric Detection for Nucleic Acid with Nanogold-Enhancement

用纳米金增效以提高微重量法检测核酸的灵敏度。实验研究了纳米金粒径大小对核酸探针固定的表面密度的影响以及探针密度对靶核酸杂交效率的影响。研究表明，核酸检测灵敏度与纳米金的粒径大小有密切关系。与粒径为5、15nm的纳米金相比，用粒径25nm的纳米金可以获得较高的杂交效率，检测的灵敏度也较高。本实验方法检测核酸的线性范围为0．05—1．2×10^-6mol／L；检出限为1．0×10^-8moL／L。

Gold nanoparticles with different sizes were utilized to enhance the immobilization of nucleic acid on the surface of quartz crystal microbalance （QCM） and reduce the steric hindrance of hybridization with target nucleic acid,which improved the sensitivity of the microgravimetric detection greatly. This enhancement effect was dependent on the size of the gold nanoparticle, in particular, higher hybridization efficiency were obtained with 25 nm gold nanoparticle compared to 5 nm and 15 nm gold nanoparticles. The linear range of this method was 0.05 - 1.2 ×10^-6 mol/L, the detection limit is 1.0 ×10^-8 mol/L.