基于一步水热合成荧光碳点的水样中亚硝酸根离子的检测研究

Detection of Nitrite in Water Samples Based on One-Step Hydrothermal Preparation of Fluorescent Carbon Dots

碳基荧光纳米点是一类新型的碳纳米材料,由于具有低毒性、生物兼容性优异、成本低、原料丰富等特点,而被广泛的应用于生物标记、荧光分析、防伪等多方面并具有巨大的应用前景。亚硝酸盐可导致人类高铁血红蛋白血症,有潜在的致癌性。通过盐酸多巴胺、邻苯二胺为原料一步水热法制备,提纯分离后得到目标产物——荧光发射波长为535 nm的黄绿色碳点。实验结果表明,该碳点溶液对亚硝酸根离子具有特异性响应,碳点的荧光被turn-off,检测范围为0~12μg·mL^(-1),检出限为0.1166μg·mL^(-1)(S/N=3,n=3)。此外,通过三种水样加标实验,回收率在93.9%~97.2%之间(RSD范围为0.03%~0.29%,n=3)。该荧光碳点合成方法快速简便,在污染物检测尤其是有毒亚硝酸盐污染物检测中有着较大的应用潜力,可作为水源地监测的重要补充手段。

In this paper,dopamine hydrochloride and o-phenylenediamine were used as raw materials,a one-step hydrothermal method was applied to design and prepare fluorescent carbon dots with emission wavelength of 535nm.The carbon dots are good water solubility and excellent fluorescent stability.The results of selective experiments showed that a specific response to nitrite by fluorescence turn-off of the carbon dots.In addition,the fluorescence carbon dots were applied to the detection of nitrite in three different spiked water samples and with recoveries from 93.9%to 97.2%and relative standard deviations of 0.03%to 0.29%.The synthesis method of the fluorescent carbon dots is simple,and the detection limit of nitrite is 0.1166μg·mL^(-1)which meet the national standard guidelines of domestic water.The carbon dots can be used as a target contaminant marker material for nitrite detection and have potential for water source monitoring system application.