基于七元瓜环可使中性红的荧光增强从而设计荧光探针, 当在荧光探针中加入百草枯后荧光强度又逐渐降低, 利用此种超分子配合物的荧光“开-关”效应, 从而建立了一种新颖的检测百草枯的荧光方法。 当百草枯浓度在(1~8)×10-6 mol·L-1范围内, 百草枯浓度与探针的荧光强度具有良好的线性关系, 且检出限为1.4×10-8 mol·L-1, 加标回收率为104%~108%, 可在河水样品中检测百草枯的含量。

We have now shown that a host-guest complex between cucurbit[7]uril (Q[7]) and neutral red (NR) can be used as a fluorescent probe for detecting the herbicide paraquat. The Q[7]/NR complex can be used to detect paraquat with high selectivity using fluorescence spectrometry. A linear correlation (ΔF=4.98+0.32c, ｒ=0.999 1) was observed between the fluorescence intensity and the concentration of PQ over the concentration range (1~8)×10-6 mol·L-1. The detection limit for PQ was 1.40×10-8 mol·L-1. Recoveries obtained with the proposed method in river water examples were 104%~108%. Such method provides a rapid, selective and sensitive strategy for herbicide detection in real samples.