Lv Wenjuan, Liu Chunyan, Ma Yao, Wang Xiang, Luo Juanjuan, Ye Weichun
Department of Chemistry, Lanzhou University, Lanzhou, 730000, China.
Department of Chemistry, Lanzhou University, Lanzhou, 730000, China; Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, Lanzhou University, Lanzhou 730000, China.
Talanta. 2019 Nov 1;204:372-378. doi: 10.1016/j.talanta.2019.06.012. Epub 2019 Jun 8.
Nanocomposites of graphene oxide/poly (diallyldimethyl ammonium chloride)/Ag nanoparticles (GO/PDDA/Ag NPs) were constructed via a self-assembly process as a surface-enhanced Raman scattering (SERS) substrate, in which functional macromolecules PDDA were utilized to load GO and support Ag NPs. Fundamental SERS performance of this SERS substrate was evaluated using rhodamine 6G (R6G), which displayed excellent enhancement effect, transferable nature and high stability of the synthesized GO/PDDA/Ag NPs substrate. Furthermore, the synthesized SERS substrate was employed in the sensitive detection of adenine with a linear range of 0.05-1000 μM and low detection limit of 1 nM. Other than the large surface area of GO, multiple-hydrogen bond interactions between adenine and the modified PDDA were another important factor in capturing adenine molecules and enhancing SERS signal. The hydrogen bond interaction was calculated using quantum mechanical calculations. Moreover, determination of adenine in aqueous solutions was achieved with good anti-interference ability against other nucleic bases with similar structures, such as guanine, cytosine and thymine. Therefore, GO/PDDA/Ag can be anticipated to be a potential substrate for label-free, fast and sensitive SERS detection of adenine in the field of bioanalysis.
通过自组装过程构建了氧化石墨烯/聚二烯丙基二甲基氯化铵/银纳米颗粒（GO/PDDA/Ag NPs）纳米复合材料作为表面增强拉曼散射（SERS）基底，其中利用功能大分子PDDA负载GO并支撑Ag NPs。使用罗丹明6G（R6G）评估了该SERS基底的基本SERS性能，其显示出合成的GO/PDDA/Ag NPs基底具有优异的增强效果、可转移性质和高稳定性。此外，合成的SERS基底用于腺嘌呤的灵敏检测，线性范围为0.05 - 1000 μM，检测限低至1 nM。除了GO的大表面积外，腺嘌呤与修饰的PDDA之间的多重氢键相互作用是捕获腺嘌呤分子和增强SERS信号的另一个重要因素。氢键相互作用通过量子力学计算得出。此外，在水溶液中测定腺嘌呤时，对鸟嘌呤、胞嘧啶和胸腺嘧啶等具有相似结构的其他核酸碱基具有良好的抗干扰能力。因此，GO/PDDA/Ag有望成为生物分析领域中用于腺嘌呤无标记、快速且灵敏的SERS检测的潜在基底。
