十六烷基三甲基溴化铵敏化孔雀石绿-脱氧核糖核酸的共振光散射增强法测定脱氧核糖核酸

Determination of Deoxyribonucleic Acids Based on the Enhanced Effect of Resonance Light Scattering of Malachite Green Sensitized by Cetyltrimethylammonium Bromide

在碱性条件下 ,脱氧核糖核酸 (DNA)对孔雀石绿的共振光散射有增强作用 ,加入十六烷基三甲基溴化铵 (CTMAB)进一步敏化该体系。共振光散射增强的程度与DNA浓度呈良好的线性关系 ,据此建立了测定DNA的共振光散射增强分析方法。在实验条件下 ,最大散射波长 36 4nm处 ,测定小牛胸腺DNA(ctDNA)和鱼精子DNA(fsDNA)的线性范围皆为 0～ 1 5 μg·mL-1,检出限分别为 0 0 5和 0 0 3μg·mL-1。该方法简单、快速、灵敏度高 ,已成功应用于合成样品中DNA含量的测定。

A resonance light scattering(RLS) enhancement method was reported for the determination of deoxyribonucleic acids. The proposed method was based on the enhanced effect of deoxyribonucleic acid on the resonance light scattering of malachite green(MG) sensitized by cetyltrimethylammonium bromide(CTMAB). Alkaline medium was necessary for the experiment. Under optimal conditions, the linear ranges for both calf thymus DNA(ctDNA) and fish sperm DNA(fsDNA) were 0-1.5 mug(.)mL(-1), the detection limits were 0.05 mug(.)mL(-1) for ctDNA and 0.03 mug(.)mL(-1) for fsDNA. The measurement can be made on normal spectrofluorimeter. Mechanic studies show that MG probably aggregates on the molecular surface of single-chained DNA, and then interacts on CTMAB to form large particles, which produce strong RLS. This method was successfully applied to the determination of DNA in synthetic samples.