中文摘要：本文报道了一种用罗明丹123(Rho123)标记的磁性二氧化硅纳米粒子（NPS）荧光为信号增强剂的高灵敏度竞争免疫测定赭曲霉素A（OTA）的方法。该方法以测量NPs表面从抗OTA的抗体包被的CdTe量子点，到Rho123染料之间发生的荧光共振能量转移(FRET)为基础。抗OTA抗体与OTA发生免疫反应，使荧光团（受体）靠近QDs（供体），引发FRET，从而激发QDs。这种高度灵敏的均相竞争性检测方法具有简单、快速和高效的特点，不需要多重分离步骤及过度洗涤。固定化量子点(QDs)光激发后的图像显示，FRET发生在QDs与Rho123之间。Rho123与磁性二氧化硅核/壳粒子的极小距离使得反应极强，从而使OTA的检测限低至0.8pg/mL。
外文摘要：We report on a highly sensitive competitive immunoassay for the mycotoxin Ochratoxin (OTA) using magnetic silica nanoparticles (NPs) fluorescently labeled with rhodamine 123 (Rho123) as signal intensifier. The method is based on the measurement of fluorescence resonance energy transfer (FRET) that occurs from CdTe quantum dots covered with anti-OTA antibody to the dye Rho123 on the surface of the NPs. The immunoreaction between anti-OTA antibody and OTA brings the fluorophore (acting as the acceptor) in close proximity of the QDs (acting as the donor), and this causes FRET to occur upon photo-excitation of the QDs. The size and polydispersity of the silica coated magnetic NPs was studied via TEM. The method has a detection limit of 0.8 pg of OTA per mL. It was applied to the determination of OTA in spiked human serum. A linear relationship is found between the increase in the fluorescence intensity of Rho 123 at 580 nm and the concentration of OTA in spiked samples over the 8 to 48 pg⋅mL−1 concentration range. This highly sensitive homogeneous competitive detection scheme is simple, rapid and efficient. It does not require multiple separation steps and excessive washing. Graphical abstract Following photoexcitation of immobilized quantum dots (QDs), FRET occurs between the QDs and Rhodamine 123. The close proximity of Rho 123 and the magnetic silica core/shell particles leads to strongly intensified emission to result in an assay for Ochratoxin A that has a detection limit as low as 0.8 pg⋅mL-1
外文关键词：Nanobiosensor；Mycotoxin；Core-shell nanoparticles；Capping；Magnetic nanoparticles；CdTe；Transmission electron microscopy；Dynamic light scattering；Food contamination
作者：Mahdi, M；Mansour, B；Afshin, M
作者单位： Islamic Azad Univ
期刊名称：MICROCHIMICA ACTA
期刊影响因子：4.831
出版年份：2016
出版刊次：12
点击下载：用基于从量子点标记抗体到罗丹明包覆的磁性纳米二氧化硅的FRET竞争性免疫法检测赭曲霉素A