摘要
研究了EGCG-Cu(Ⅱ)-ctDNA系统的荧光光谱,电子吸收光谱和共振光散射光谱(RLS)。与EGCG-Cu(Ⅱ)二元配合物比较,EGCG-Cu(Ⅱ)-ctDNA三元体系光谱显示以下特征:(1)荧光光谱的发射位置没有变,荧光强度显著增强,并且三元体系的荧光强度随着DNA浓度增大而增大。在适宜的条件下,Cu(Ⅱ)-EGCG配合物有望成为检测ctDNA的荧光探针;(2)电子吸收光谱有明显的增色效应;(3)共振光散射强度也增强。三种光谱的特征显示,EGCG-Cu(Ⅱ)配合物与核酸之间主要依靠插入作用和静电引力结合。由于配合物的插入,使系统的荧光强度增强,而静电作用使其电子吸收光谱和共振光散射光谱产生增色效应。酸度和离子强度对三元系统荧光强度的影响也进行了实验和讨论。
The fluorescence spectra, absorption spectra and resonance light scattering （RLS） spectra of EGCG-Cu（Ⅱ） complex with nucleic acid were studied. Compared with the spectrum of EGCG-Cu（Ⅱ）, the spectrum of EGCG-Cu（Ⅱ）-DNA system showed the following features： （ 1 ） in the fluorescence spectra, the peak did not shift, but the fluorescence intensity was enhanced and was proportional to the concentration of DNA. Under suitable conditions, EGCG-Cu（Ⅱ） promised to be a probe for detecting DNA; （2） Absorption spectra of EGCG-Cu（Ⅱ）-DNA system showed hyperchromicity; and （3） RLS of EGCG-Cu （ Ⅱ）-DNA system was enhanced also. A mechanism was suggested that the combination of nucleic acid and EGCG-Cu（Ⅱ ） complex was caused by intercalation and electrostatic force. An intercalation interaction between EGCG-Cu（ Ⅱ ） and DNA enhanced the fluorescence intensity. Hyperchromicity of absorption spectra and RLS occurred because of electrostatic force. The effects of acid and ionic strength on fluorescence intensity were also discussed.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2007年第3期510-513,共4页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目(30270786)资助
