基于室温磷光量子点/硼酸基联吡啶盐纳米复合材料检测果糖

以Mn掺杂的ZnS(Mn-ZnS)室温磷光(RTP)量子点的磷光为信号,以2-溴甲基苯硼酸与4,4ˊ-联吡啶为原料合成的硼酸基联吡啶盐(BBV)为受体,带负电的量子点与带正电BBV通过静电作用形成Mn-ZnS/BBV纳米复合材料,Mn-ZnS量子点磷光猝灭,加入果糖,BBV与果糖形成阴离子硼酸酯,降低了对量子点猝灭效率,RTP恢复.考察了时间、pH值对Mn掺杂的ZnS QDs/BBV纳米复合材料磷光强度的影响,在最优条件下,此传感器检测果糖的线性范围为0.05~1.00 mmol/L,检出限为0.01 mmol/L,相关系数r为0.99.本磷光分析法简便快速、灵敏度高,有望应用于食品、医药行业中果糖含量的检测分析.

Synthesis of Quantum Dot / Boronic Acid-substituted Bipyridinium Salt Nanohybrids as Room-temperature Phosphorescence Probe for Fructose Detection

Trace level of fructose was successfully detected by a sensor, in which the phosphorescence of Mn-doped ZnS (Mn-ZnS) room-temperature phosphorescence (RTP) quantum dots (QDs) was used as signals, and boronic acid-substituted bipyridinium salt (BBV) synthesized from 2-(bromomethyl) phenylboronic acid and 4,4ˊ-bipyridyl was used as the receptor. The negatively-charged Mn-ZnS QDs and the positively-charged BBV electrostatically attracted each other to form Mn-ZnS QDs/ BBV nanohybrids, which quenched the RTP of Mn-ZnS QDs. After addition into these nanohybrids, the fructose bonded with BBV to form an anionic borate, which largely restricted the quenching of BBV on Mn-ZnS QDs, thus the RTP was restored. In this work, we investigated the effects of pH and reaction time on the RTP of the Mn-ZnS QDs/ BBV nanohybrids. Under the optimal conditions, the novel probe had a fructose detection limit of 0. 01 mmol/ L and a linear range of 0. 05-1. 0 mmol/ L was achieved with correlation coefficient of 0. 99. This phosphorescence sensor was superior with convenience and high speed, and can be potentially applied to the detection and analysis of fructose in foods and medicine fields.