链状磁光纳米核壳等离激元Fano共振增强光电化学生物传感

In order to further increase the sensitivity of localized surface plasmon in noble metal nanoparticles based photoelectrochemical (PEC) sensors and its selectivity in complex real samples, the novel Fano resonances in plasmonic magneto-optic nano core-shell, such as Fe3O4@TiO2@Au, for enhanced PEC biosensing will be developed in this project. Herein, magneto-optic nano core-shell has two noteable features of magnetism induced plasmonic Fano resonances and enrichment of magnetic separation. Firstly, new approaches will be developed for controllable synthesis and directional monolayer assembly of magneto-optic nano core-shell beacons. Secondly, the coupling of localized surface plasmon and surface plasmon polariton for noble metal shells will be mediated. Thirdly, the crucial influence factors of plasmonic Fano resonances will be further investigated, such as the size, interparticle spacing, refractive index of surrounding medium, resonance energy and electric field component. Fourthly, the effects of magnetic properties of magneto-optic nano core-shell on target molecule separation will be explored systematically based on the biological affinity. Finally, a novel theory and system for magneto-optic nano core-shell based PEC biosensing will also be further investigated. Then, the novel magnetism induced PEC biosensors with high performances in good sensitivity, selectivity, stability and fast detection will be constructed. It will provide a new platform for efficient detection of pesticide residues and food safety warning, and will also promote the development of PEC sensing.

为进一步提高纳米贵金属局域表面等离激元基光电化学传感灵敏度及其在复杂体系中的特异性，基于磁光纳米核壳等离激元Fano共振和磁分离富集的特性，本项目拟开展磁光纳米核壳（如Fe3O4@TiO2@Au）等离激元Fano共振增强光电化学传感新体系研究。发展可控制备和单层定向组装磁光纳米核壳信标新方法；调控壳层贵金属局域表面等离激元和表面等离极化激元耦合并实现等离激元Fano共振；探究影响等离激元Fano共振的关键参数如颗粒尺寸、粒子间距、周围介质折射率、共振能量及电场分量等；再结合生物特异性作用，考察磁光纳米核壳磁性特征对靶标分离的影响；探讨磁光纳米核壳基等离激元Fano共振增强光电化学生物传感新理论和新机制。本项目拟创造性地构建灵敏度高、选择性好、稳定性佳及检测速度快的新型磁光电化学生物传感器，为复杂体系中农残的高效、可靠检测及食品安全预警机制的建立提供新平台，并促进光电化学分析领域进一步发展。

传统的光电化学传感器的构建往往需要通过冗长的电极材料层层组装以及多次电极润洗步骤才可以实现，这样的设计很耗时，同时不能保证光电极的稳定性和制作重现性。面向复杂的实际样品，其选择性也有限。另外，其灵敏度也有待于进一步提高。在本项目研究中，基于磁光纳米核壳等离激元Fano共振和磁分离富集的特性，本项目开展了磁光纳米核壳等离激元Fano共振增强光电化学传感新体系研究。发展了可控制备和单层定向组装磁光纳米核壳信标新方法；调控壳层贵金属局域表面等离激元和表面等离极化激元耦合并实现了等离激元Fano共振；探究了影响等离激元Fano共振的关键参数如颗粒尺寸、粒子间距、周围介质折射率、共振能量及电场分量等；并结合生物特异性作用，考察了磁光纳米核壳磁性特征对靶标分离的影响；阐述了不同的生物信号放大策略对光电化学传感器灵敏度提高及稳定性的影响；探讨了磁光纳米核壳基等离激元Fano共振增强光电化学生物传感新理论和新机制。本项目创造性地构建了灵敏度高、选择性好、稳定性佳及检测速度快的新型磁光电化学生物传感器，为复杂体系中农残、有害气体、疾病标志物的高效、可靠检测及人类健康安全预警机制的建立提供了新平台，并促进了光电化学分析领域进一步发展。