ABSTRACT

A magnetic separation-based immunosensor for deoxynivalenol assay, coupled with a nano-affinity cleaning up for instrumental confirmation, was developed. Maltose-binding protein with mimic epitope of DON was coupled to CdSe/ZnS quantum dot nanobeads for fluorescent reporter. Graphene oxide was linked with magnetic nanoparticles and protein G for immunomagnetic adsorbent. The magnetic separation of reporter could be inhibited by DON so the fluorescent remained in the solution indicates a good quantitative correlation to DON concentration. The DON separated by immune adsorbent can be cleaned up for instrumental confirmation. The optimized immunosensor showed results as follows: the linear range was in 0.3–3000 ng mL⁻¹. The limits of detection (S/N = 3) were 0.50, 1.0, and 3.0 ng mL⁻¹ in different backgrounds. The recoveries for DON-spiked samples range from 78.7% to 88.5%. Both results of UPLC-MS/MS based on affinity column purification and coupled with nano-affinity cleaning up showed a good agreement with the current immunosensor.

摘要

开发了一种用于脱氧雪腐酚测定的基于磁分离的免疫传感器，以及用于仪器确认的纳米亲和力净化技术。具有DON模拟表位的麦芽糖结合蛋白与CdSe / ZnS量子点纳米珠偶联，用于荧光报告基因。氧化石墨烯与磁性纳米颗粒和蛋白质G相连，形成免疫磁性吸附剂。DON可以抑制报告基因的磁分离，因此溶液中残留的荧光表明与DON浓度具有良好的定量相关性。可以清除被免疫吸附剂隔开的DON，以进行仪器确认。优化的免疫传感器显示以下结果：线性范围为0.3–3000 ng mL ^-1。检测限（S / N = 3）为0.50、1.0和3.0 ng mL ^-1在不同的背景。DON加标样品的回收率在78.7％至88.5％之间。基于亲和柱纯化的UPLC-MS / MS结果与纳米亲和纯化相结合，均表明与当前的免疫传感器具有良好的一致性。