Wang Aiqing,Cui Yuezhi,Tao Furong,Gu Caihong,Wang Shijie,Li Tianduo
A functionalized glass sensor ( G-P ) was prepared for detecting nitroaromatic compounds (NACs) by chemically immobilizing a conjugated polymer P on the surface of a glass slide. The monolayer film sensor had several advantages: the signal amplification effect of conjugated polymers, no leakage of sensing materials in solution, and good permeability for the analytes. Fluorescence quenching studies demonstrated that the sensor was highly sensitive to NACs. When the DNT concentration was 1.03 × 10 –7 mol/L, the quenching efficiency (1– I / I
0 ) of G-P reached 52.8%. Moreover, the excellent properties of reversibility, selectivity and sensitivity indicated the glass G-P might be a promising sensor in the field of explosives detection.
In this study, we present a simple but effective fluorescent system for highly sensitive and versatile sensing of 2,4,6-trinitrotoluene (TNT) using few layered planar MoS2 quantum dots (QDs) as reporters. Excitation-independent emitting MoS2 QDs were first fabricated by using the proposed ultrasonic–hydrothermal-based top-down method assisted by carbon-free hydroxylamine hydrochloride. The obtained pristine MoS2 QDs were then modified with cysteine for introducing amino groups as TNT binding sites. The as-prepared MoS2 QDs possess a planar structure, which can more adequately interact with flat aromatic TNT molecules due to π–π attraction and decreased steric effects, compared with traditional spherical/quasi-spherical QDs. As a result, they exhibit extremely high sensitivity for TNT sensing (1 nM and 2 ng for solution and substrate assay, respectively). The common ions containing in environmental water samples do not interfere with the sensing. Furthermore, the QDs-decorated test paper shows an instantaneous (within 1 min) response to trace amounts of deposited TNT, and the fluorescence quenching can even be well-visualized by the naked eye. Because of favorable analytical performances, the proposed MoS2 QDs-based TNT sensing system has potential applications in both environmental water monitoring and security screening.
危险品化学品经营许可证（带存储）