摘要
基于在pH 1．7的KCl-HCl缓冲液中核酸对大黄有效成分大黄酸481 nm处共振光散射信号的猝灭现象,建立了测定核酸的共振光散射新方法．在最优条件下,该方法对小牛胸腺DNA和酵母RNA的线性范围、检测限分别为0．045-9．0μg／mL,33．9 ng／mL和0．0600-9．0μg／mL,45．9 ng／mL．该方法已用于核酸合成样品和实际样品中ctDNA和yRNA的测定,结果令人满意．此外,还通过计算机模拟对大黄酸分子与核酸分子结合前后分子平面性的变化进行了考察,探讨了分子平面性变化与共振散射光猝灭之间的关系．
At pH 1.7, a combination of rhein with some nucleic acids such as calf thymus DNA（ctDNA） or yeast RNA（yRNA）, can result in a great quenching of resonance light scattering and the maximum scattering wavelength appears at 481 nm. Based on this, a new method for the determination of trace amounts of nucleic acids has been developed. Under optimal conditions, the calibration graphs are linear over the range of 0.045～9.0 μg/mL for ctDNA and 0.060～9.0 μg/mL for yRNA. The corresponding detection limits are 33.9 ng/mL for ctDNA and 45.9 ng/mL for yRNA, respectively. The method has been applied to determine the ctDNA and yRNA in four synthetic samples and three real samples with a recovery range between 98.5% and 101.2%. Moreover, the quenching reasons of RLS and the interaction mechanism have been primarily discussed and the coplanarity change of rhein molecule before and after combination with ctDNA have been calculated.
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2006年第4期61-65,共5页
Journal of Lanzhou University(Natural Sciences)
基金
国家自然科学基金资助项目(20275014).
关键词
大黄酸
小牛胸腺DNA
共振光散射猝灭
反应机理
rhein
calf thymus DNA
quenching of resonance light scattering
interaction mechanism
