【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。更多还原

【Abstract】 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.更多还原