用新洁尔灭测定核酸的共振瑞利散射方法研究

A Study on the Determination of Nucleic Acids by a Resonance Rayleigh Scattering Technique with Benzalkonium Bromide

在酸性BR缓冲溶液中 ,新洁尔灭 (溴化十二烷基二甲基苄铵 ,BB)与小牛胸腺DNA (ctDNA)鲱鱼精DNA (hs DNA)、鲑鱼精DNA (sDNA)和酵母RNA (yRNA)反应 ,产生强烈的共振瑞利散射 (RRS)增强 ,其最大散射峰位于 470nm处 .由此建立测定微量核酸的新分析方法 .ctDNA ,hsDNA ,sDNA和yRNA的测定范围分别为 0～ 4 2 μg/mL ,0～4 0 μg/mL ,0～ 4 6 μg/mL ,0～ 12 0 μg/mL ;检出限 (3σ)分别为 8 6ng/mL ,9 2ng/mL ,9 9ng/mL和 2 7 9ng/mL .研究发现RRS强度变化与核酸构象转变有密切联系 。

In an acidic Britton-Robinson buffer solution, benzalkonium bromide (dodecyldimethyl benzylammonium bromide, BB) can react with nucleic acids such as ctDNA,hsDNA, sDNA and yRNA, which leads to the great enhancement of resonance Rayleigh scattering (RRS), and the maximum RRS peak is located at 470 nm. Therefore, a new method for the determination of trace nucleic acids was found. The linear ranges for the determination of nucleic acids are 0～4.2 μg/mL for ctDNA, 0～4.0 μg/mL for hsDNA, 0～4.6 μg/mL for sDNA, 0～12.0 μg/mL for yRNA. The detection limits (3σ) are 8.6 ng/mL for ctDNA, 9.2 ng/mL for hsDNA, 9.9 ng/mL for sDNA and 27.9 ng/mL for yRNA, respectively. The intimate relationship between the intensity of RRS and the structure transition of nucleic acids has been summarized. Therefore, the RRS method will become possibly an available approach for studying DNA structures.