基于碳量子点内滤作用测定水样中对硝基苯酚

Determination of P-Nitrophenol in Water Samples Based on Carbon Dots by Inner Filter Effect

以蚂蚱粉末为碳源,利用硝酸与乙二胺酸碱反应的反应热实现快速、简便制备碳量子点(CDs)。所制备的CDs的最佳激发波长为390 nm,发射峰为470 nm。由于对硝基苯酚(p-NP)在400 nm处具有特征吸收,与CDs的荧光激发峰具有良好的光谱重叠,使p-NP对CDs具有明显的内滤作用,且其它硝基苯化合物的吸收峰几乎不与CDs荧光发射峰重叠,因此不产生荧光内滤作用。基于该荧光内滤作用,建立了p-NP的高灵敏度,高选择性荧光分析新方法。该分析方法检出限(3σ)为0.13 μM,相对标准偏差(RSD)为4.09% (c = 10 μM, n = 11),线性范围是0.5~80 μM。该方法已成功应用于环境水样中痕量p-NP的检测。

Carbon Dots (CDs) were prepared using locust powder as carbon source through the exothermic reaction between nitric acid and ethylenediamine. The optimal excitation wavelength and emission peak of CDs prepared were 390 nm and 470 nm respectively. Due to the characteristic absorption of p-Nitrophenol (p-NP) at 400 nm, which has a good spectral overlap with the fluorescence excitation peak of CDs, then P-NP has an obvious Inner Filter Effect (IFE) on the fluorescence emission of CDs. Moreover, the absorption peak of other nitrobenzene compounds hardly overlaps with the fluorescence excitation and emission peak of CDs, so no IFE is generated. A new analytical method for p-NP was established based on IFE with high sensitivity and selectivity. The detection limit (3σ) of the method for p-NP was 0.13 μM, and Relative Standard Deviation (RSD) was 4.09% (c = 10 μM, n = 11), and the linear range was 0.5~80 μM. The method has been successfully applied to the determina-tion of trace p-NP in environmental water samples.