【摘要】 在pH 2 .2 1的酸性介质中 ,Al3+ 与脱氧核糖核酸 (DNA)发生静电作用产生以 2 91.0nm为特征峰的共振光散射 (RLS)增强光谱 ,即Al3+ 主要与DNA分子表面的磷酸根结合 ,但DNA热变性将导致Al3+ 与DNA的碱基结合 ,使光散射信号降低。在 2 91.0nm处的共振光散射 (RLS)强度与DNA的浓度呈线性关系 ,据此建立了用共振光散射测量痕量DNA的新方法。方法的检出限为ng级 ,用于合成样分析 ,回收率在 91.6 %～ 10 5 .0 %。更多还原

【Abstract】 In an acidic medium of pH 2.21, the interaction of Al 3+ with deoxyribonucleic acid (DNA) results in enhanced resonance light scattering (RLS) spectra characterized by a peak at 291nm. That is, Al 3+ is mainly in combination with phosphate ion of the surface of DNA molecule. Thermally denaturation of double stranded DNA will lead to interaction of Al 3+ with base of DNA, and will decreased the RLS signals. It was found that under the optimal condition the enhanced RLS intensity at 291.0 nm was proportional to the concentration of DNA, and a RLS method for the determination of trace DNA was accordingly established. The limit of determination was nanogram level. The present method was successfully applied to the determination of DNA in synthetic samples with the recovery of 91.6%～105.0%.更多还原