表面增强拉曼光谱检测腺嘌呤共平面的G四链体

The G-Quadruplexes Containing of Adenine Coplanar G-Quartet Revealed by Surface-Enhanced Raman Spectroscopy

G-四链体是由富含鸟嘌呤的寡核苷酸构成的DNA二级结构。前期利用含有碘和铝离子的银纳米材料(Ag IANPs)测定G四链体时发现,当腺嘌呤(A)与鸟嘌呤(G)形成的G4平面共平面时,A碱基的环呼吸共振峰强度显著增强。而当A位于G四链体结构中其他位置时,A碱基峰强度随着A碱基的数量增加而稳步增强,与A和G共平面时的情况相比,没有特殊的上升趋势。基于此,进一步分析了另外三种含有A共平面的G四链体,获得了特殊地增强的A碱基信号峰。提出了利用SERS峰强度来分析含有A共平面的G四链体,为检测DNA分子空间结构提供了新途径。

G-quadruplexes are secondary structures of DNA that are formed by guanine-rich oligonucleotides.In a previous work,we found that when adenine(A)and four guanines(G4)located in the same plane,the characteristic peak intensity of A base is greatly enhanced.However,when A is located at other locations of the G-quadruplex,even if the number of bases of A is large,the characteristic peak intensity of A is low.Based on this,we further analyzed the other three G-quadruplexes containing coplanar A and G-quartet,the results confirmed our assumption.Thus,the verification of this rule provides a new way for the characterization of G-quadruplex containing A which is coplanar with G-quartet.