Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China.
Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China.
Talanta. 2020 May 1;211:120705. doi: 10.1016/j.talanta.2019.120705. Epub 2019 Dec 31.
Barium sulfate-coated CsPbBr perovskite nanocrystals (CsPbBr NCs@BaSO) was successfully synthesized that exhibited stable and intense fluorescence property in aqueous buffer. With the CsPbBr NCs@BaSO as signal readout, an ultrasensitive fluorescence nanosensor was developed for turn-on determination of melamine by the manipulation of inner filter effect of citrate-protected gold nanoparticles (AuNPs). The fluorescence of the CsPbBr NCs@BaSO was remarkably quenched by the AuNPs due to inner filter effect. This inner filter effect could be weakened by the addition of melamine as a result of melamine-triggering aggregation of the AuNPs and subsequently led to a recovery in the fluorescence of the CsPbBr NCs@BaSO. The recovery ratio was proportional to the concentration of melamine in the range of 5.0-500.0 nmol/L. The limit of detection was 0.42 nmol/L and the relative standard deviation was 4.0% for the repetitive determination of 500.0 nmol/L melamine solution (n = 11). The nanosensor was successfully applied to analysis of melamine in dairy product samples.
成功合成了硫酸钡包覆的 CsPbBr 钙钛矿纳米晶（CsPbBr NCs@BaSO），其在水性缓冲液中表现出稳定且强烈的荧光性质。利用 CsPbBr NCs@BaSO 作为信号读出，通过操纵柠檬酸保护的金纳米粒子（AuNPs）的内滤效应，开发了一种用于三聚氰胺的超灵敏荧光纳米传感器。由于内滤效应，AuNPs 显著猝灭了 CsPbBr NCs@BaSO 的荧光。由于三聚氰胺引发 AuNPs 的聚集，这种内滤效应可以被削弱，从而导致 CsPbBr NCs@BaSO 的荧光恢复。荧光恢复率与三聚氰胺的浓度成正比，在 5.0-500.0 nmol/L 范围内。该传感器对 500.0 nmol/L 三聚氰胺溶液进行重复测定的检出限为 0.42 nmol/L，相对标准偏差为 4.0%（n = 11）。该纳米传感器成功应用于乳制品样品中三聚氰胺的分析。
