Muniz-Miranda Francesco, Pedone Alfonso, Muniz-Miranda Maurizio
Department of Chemical and Geological Sciences (DSCG), University of Modena and Reggio Emilia (UniMORE), Via Campi 103, 41125 Modena, Italy.
Department of Chemistry "Ugo Schiff", University of Florence (UniFI), Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy.
ACS Omega. 2018 Oct 18;3(10):13530-13537. doi: 10.1021/acsomega.8b02174. eCollection 2018 Oct 31.
Xanthine is a nucleobase, deriving from adenine and guanine by deamination and oxidation processes, which may deposit in the human body causing diseases, similar to uric acid. Here, we have investigated the adsorption of xanthine on silver colloidal nanoparticles by means of surface-enhanced Raman scattering (SERS) with an exciting radiation in the near-infrared spectral region, where interference due to fluorescence does not occur, along with density functional theory calculations of molecule/metal model systems. By adopting a combined experimental and computational approach, we have identified the "marker" SERS bands of xanthine and the tautomer that preferentially binds the silver particles, as well as the molecular group involved in the interaction with metal. This investigation allows using the FT-SERS spectroscopy for biosensory and diagnostic purposes in body fluids, detecting abnormal levels of xanthine, and preventing metabolic diseases.
黄嘌呤是一种核碱基，通过脱氨和氧化过程由腺嘌呤和鸟嘌呤衍生而来，它可能沉积在人体中导致疾病，类似于尿酸。在这里，我们通过表面增强拉曼散射（SERS），利用近红外光谱区域的激发辐射，研究了黄嘌呤在银胶体纳米颗粒上的吸附情况，在该区域不会出现荧光干扰，同时还进行了分子/金属模型系统的密度泛函理论计算。通过采用实验和计算相结合的方法，我们确定了黄嘌呤的“标记”SERS谱带以及优先结合银颗粒的互变异构体，还有参与与金属相互作用的分子基团。这项研究使得利用傅里叶变换表面增强拉曼光谱（FT-SERS）技术用于体液中的生物传感和诊断目的成为可能，检测黄嘌呤的异常水平，并预防代谢性疾病。
