非荧光硫化锌纳米簇的信号放大效应用于生物分子的检测

摘要

利用非荧光硫化锌纳米簇(NCCs)阳离子交换(CX)反应检测痕量生物分子。水热法合成的纳米簇是多孔的,可以通过快速阳离子交换反应从纳米簇中释放大量的 Zn2+,在锌响应试剂的作用下产生荧光信号,进行荧光检测。当纳米簇的平均直径分别为44,86和144 nm 时,研究了 Zn2+的释放效率和目标结合力与平均直径之间的关系。结果表明,最小的纳米簇表现出最高的阳离子交换效率,71%被封闭的 Zn2+可以在2 min 内通过微波辐射释放出来。当使用44 nm 纳米簇夹心法测定免疫球蛋白 E(IgE)时,检出限为5 ng/ L,比 ELISA 法低1000倍。结果表明,利用硫化锌纳米簇的阳离子交换作用,所得结果在高扩增效率、稳定性和生物相容性方面优于传统的信号方法。%Cation exchange (CX) reaction for the non-fluorescent ZnS nanocrystal clusters (NCCs) can be used to detect trace biomolecules . Nano clusters synthetized by hydrothermal synthesis are porous. So they can quickly release large amounts of Zn2+ from through cation exchange ( CX) reaction and nano cluster, generate fluorescent signal under the action of zinc reagent to detect fluorescence. The relationship between the release efficiency, target binding force of Zn2+ and its average diamete was investigated when the average diameter was 44 nm, 86 nm and 144 nm in this experiment. Results showed that the smallest nano cluster exhibited the highest cation exchange efficiency, and 71 percent of Zn2+ closed could be released by microwave radiation within 2 min. When the sandwich method of NCCs of 44-nm was used to detect immunoglobulin E (IgE) in a sandwich assay, the limit of detection (LOD) was 5 ng / L, which was 1000 times lower than that of ELISA. It turns out that CX for the ZnS NCCs is superior to the conventional signaling strategies in its high amplification efficiency, robustness, and biocompatibility.