连续识别Zn2+和草甘膦荧光探针的合成与应用

Synthesis and application of novel fluorescent probe for the sequential recognition of Zn2+ and glyphosate

摘要:

以2-巯基苯并噻唑为原料，设计合成了一种结构简单的苯并噻唑类荧光探针NSS，并通过IR、HRMS、1HNMR、13CNMR等对其结构进行表征。荧光发射光谱表明，在DMSO溶液中，探针NSS实现了Zn2+的“Turn-ON”型检测，具有响应时间短、特异性强、抗干扰性强等优点。探针NSS荧光强度与Zn2+浓度（0～11 μmol/L）呈现良好的线性关系，检出限达19.1 nmol/L，并与Zn2+形成1:1络合物。同时，络合物NSS-Zn2+对草甘膦呈现特异性的荧光猝灭响应，猝灭率达99.4%，检出限16.0 nmol/L（2.68 ng/mL），且不受其它有机磷农药的干扰。此外，探针NSS成功应用于实际水样中Zn2+和草甘膦的检测，具有良好的应用前景。

Abstract:

A fluorescent probe NSS of benzothiazole derivatives was synthesized using 2-mercaptobenzothiazole as raw material and the structure was characterized by IR, MS, 1H NMR, 13C NMR. The fluorescence spectroscopy studies demonstrated that the probe NSS showed fast-response, high selectivity and good anti-interference ability towards Zn2+ ion through the significant fluorescence enhancement effect in the DMSO solution. The fluorescence intensity of probe NSS had a good linear relationship with the concentration of Zn2+ (0～11 μmol/L), and the detection limit could reach 19.1 nmol/L. The bingding stoichiometry of probe NSS with Zn2+ was 1:1, which was confirmed by Job's plot analysis and MS. Meanwhile, complex NSS-Zn2+ had obviously fluorescence intensity quenched response to glyphosate while suffering from a slight interference in the presence of other organophosphorus pesticides. The quenching efficiency reached a maximum of 99.4%, and the detection limit of complex NSS-Zn2+ to glyphosate was 16.0 nmol/L (2.68 ng/mL). In addition, probe NSS was succesfully used in the detection of Zn2+ and glyphosate in the actual water samples, the method had potential application in the field of environmental detection.