Tramonti Vania, Lofrumento Cristiana, Martina Maria Raffaella, Lucchesi Giacomo, Caminati Gabriella
Department of Chemistry and CSGI, University of Florence, Via della Lastruccia 3-13, 50019 Sesto Fiorentino, Italy.
Nanomaterials (Basel). 2022 Feb 10;12(4):600. doi: 10.3390/nano12040600.
We propose a sensing platform based on graphene oxide/silver nanoparticles arrays (GO/AgNPs) for the detection and discrimination of the native and toxic fibrillar forms of an amyloid-prone protein, lysozyme, by means of a combination of Quartz Crystal Microbalance (QCM) and Surface Enhanced Raman Scattering (SERS) measurements. The GO/AgNPs layer system was obtained by Langmuir-Blodgett assembly of the silver nanoparticles followed by controlled adsorption of GO sheets on the AgNPs array. The adsorption of native and fibrillar lysozyme was followed by means of QCM, the measurements provided the kinetics and the mechanism of adsorption as a function of protein concentration as well as the mass and thickness of the adsorbed protein on both nanoplatforms. The morphology of the protein layer was characterized by Confocal Laser Scanning Microscopy experiments on Thioflavine T-stained samples. SERS experiments performed on arrays of bare AgNPs and of GO coated AgNP after native, or fibrillar, lysozyme adsorption allowed for the discrimination of the native form and toxic fibrillar structure of lysozyme. Results from combined QCM/SERS studies indicate a general construction paradigm for an efficient sensing platform with high selectivity and low detection limit for native and amyloid lysozyme.
我们提出了一种基于氧化石墨烯/银纳米颗粒阵列（GO/AgNPs）的传感平台，通过石英晶体微天平（QCM）和表面增强拉曼散射（SERS）测量相结合的方法，用于检测和区分易形成淀粉样蛋白的溶菌酶的天然和有毒纤维状形式。GO/AgNPs层系统是通过银纳米颗粒的朗缪尔-布洛杰特组装，然后在AgNPs阵列上控制吸附GO片层获得的。通过QCM跟踪天然和纤维状溶菌酶的吸附情况，测量提供了吸附动力学、吸附机制与蛋白质浓度的函数关系，以及两种纳米平台上吸附蛋白质的质量和厚度。通过对硫黄素T染色样品进行共聚焦激光扫描显微镜实验，对蛋白质层的形态进行了表征。在天然或纤维状溶菌酶吸附后，对裸AgNPs阵列和GO包覆的AgNP阵列进行SERS实验，能够区分溶菌酶的天然形式和有毒纤维状结构。QCM/SERS联合研究的结果表明了一种高效传感平台的通用构建范式，该平台对天然和淀粉样溶菌酶具有高选择性和低检测限。
