基于MOF@TiN-Ag/银溶胶复合基底的茶碱表面增强拉曼检测

Surface-enhanced Raman Detection of Theophylline Based on MOF@TiN-Ag/Ag Sol Composite Substrate

以制备的MOF@TiN-Ag/银溶胶复合基底为表面增强拉曼光谱(SERS)活性基底,对茶碱进行SERS检测,探讨了基于该复合基底的表面增强拉曼技术在药物检测方面的应用。首先,利用电化学阳极氧化结合氨气还原氮化法制备了氮化钛纳米管阵列,随后通过电化学沉积法制备TiN-Ag复合基底,并在其表面原位生长金属有机框架(MOF)包覆层得到MOF@TiN-Ag复合基底,将茶碱与银溶胶混合后滴加在该复合基底上进行表面增强拉曼光谱检测。结果表明,MOF@TiN-Ag/银溶胶复合基底中存在面心立方晶型TiN、金属单质Ag和MOF钴基3种物相;扫描电镜结果显示,TiN纳米管排列整齐,Ag纳米结构呈树枝状均匀分散在其表面;作为隔绝层的MOF粒子形状规整,覆盖在TiN-Ag表面;银溶胶纳米粒子呈圆球状分布在MOF@TiN-Ag复合基底表面。由于银纳米粒子与TiN-Ag复合基底可发生协同增强作用,加之MOF的富集特性,使得该复合基底具有优异的SERS性能,其对茶碱溶液的SERS检出限为1×10^(-5) mol/L,检测性能良好。所制备的MOF@TiNAg/银溶胶复合基底拓宽了SERS在药物检测领域的应用。

The MOF@TiN-Ag/silver sol composite substrate was utilized as an active substrate for the surface-enhanced Raman spectroscopy(SERS)of theophylline.This study discusses the application of this composite substrate for surface-enhanced Raman technology in drug detection.Initially,titanium nitride nanotube arrays were fabricated using electrochemical anodic oxidation combined with ammonia reduction nitration method.Subsequently,TiN-Ag composite substrates were prepared through electrochemical deposition,and a metal-organic framework(MOF)coating layer was grown in situ to obtain MOF@TiN-Ag composite substrates.Theophylline was then added dropwise onto the composite substrates for SERS detection after being mixed with the silver sol.The results revealed that the MOF@TiN-Ag/silver sol composite substrate comprises three phases:face-centered cubic TiN,metal monolithic Ag,and cobalt-based MOF.Scanning electron microscopy results demonstrated that the TiN nanotubes have a regular structure,and Ag nanostructures are uniformly dispersed on the surface in a dendritic form.MOF particles serve as an isolation layer with a regular shape and cover the surface of TiN-Ag.The spherical silver sol nanoparticles are distributed on the MOF@TiN-Ag composite substrate.Due to the synergistic enhancement of silver nanoparticles and TiN-Ag composite substrate,coupled with the enrichment property of MOF,the composite substrate exhibits excellent SERS performance.It has a SERS detection limit for theophylline solution of 1×10^(-5) mol/L,demonstrating good detection performance.The prepared MOF@TiN-Ag/silver sol composite substrate expands the application of SERS in drug detection.