氮硼共掺杂碳量子点的制备及其对六价铬的检测

Preparation of nitrogen-boron-doped carbon quantum dots and its application for hexavalent chromium detection

目的建立一种基于荧光碳量子点的快速检测方法,定量检测饮用水和食品中的六价铬[hexavalent chromium,Cr(Ⅵ)]。方法以无水柠檬酸和3-氨基苯硼酸分别作为碳、氮和硼源,通过一步水热法合成氮硼共掺杂碳量子点(nitrogen-boron-doped carbon quantum dots,N,B-CQDs),基于荧光内滤效应对Cr(Ⅵ)进行检测。结果在优化后的最佳检测条件下,N,B-CQDs对Cr(Ⅵ)在0.01~10.00 mg/L内呈现良好的线性关系,检出限低至3.81μg/L,表现出选择性好、灵敏度高等特点。将此方法应用于饮用水、白醋和虾皮中Cr(Ⅵ)含量的测定,加标回收率在85.8%~112.3%之间,相对标准偏差低于5%。结论本研究制备的N,B-CQDs在Cr(Ⅵ)检测方面具有检出限低、灵敏度高、选择性好等优点,可以为Cr(Ⅵ)快速检测提供一定的理论和技术参考。

Objective To establish a rapid detection method based on fluorescent carbon quantum dots for the quantitative determination of hexavalent chromium[Cr(Ⅵ)]in water and food stuffs.Methods Nitrogen-borondoped carbon quantum dots(N,B-CQDs)were synthesized by a one-step hydrothermal method using anhydrous citric acid and 3-aminobenzeneboronic acid as carbon,nitrogen and boron sources,respectively.Cr(Ⅵ)was quantitatively detected based on the fluorescence internal filtration effect.Results Under the optimal detection conditions,N,B-CQDs showed a good linear relationship with Cr(Ⅵ)in the range of 0.01-10.00 mg/L,and the limit of detection was as low as 3.81μg/L,showing the characteristics of good selectivity and high sensitivity.The method was applied to the determination of Cr(Ⅵ)in water,white vinegar and shrimp skin.The recoveries of Cr(Ⅵ)were 85.8%-112.3%,and the relative standard deviation was less than 5%.Conclusion The N,B-CQDs prepared in this study has the advantages of low limit of detection,high sensitivity and good selectivity in the detection of Cr(Ⅵ),which can provide a theoretical and technical reference for Cr(Ⅵ)rapid detection.