The nitrite ion (NO2-) is a vital inorganic species that occurs both in natural ecological systems and human bodies. The high concentration of NO2- can be harmful for animal and human health. It is important to develop a simple, sensitive, reliable, and economic methodology to precisely monitor NO2- in various environmental and biological fields. Thus, a novel nitrite biosensor based on carbon quantum dots (PA-CDs) has been constructed and prepared via a high-efficiency, one-pot hydrothermal route using primary arylamines (PA) such as m-phenylenediamine. The device exhibits bright green fluorescence and a high quantum yield of 20.1% in water. In addition, the PA-CDs also possess two broad linear ranges: 0.05-1.0 μM and 1.0-50 μM with a low detection limit of 7.1 nM. The classical diazo reaction is firstly integrated into the PA-CD system by primary arylamines, which endows the system with high sensitivity and specific selectivity towards nitrite. Importantly, the nanosensor can detect NO2- in environmental water and serum samples with high fluorescence recoveries, demonstrating its feasibility in practical applications. This work broadens a new method to fabricate novel nanosensors and provides a prospective application for fluorescent carbon quantum dots (CDs). Graphical abstract.

中文翻译：

---

具有碳量子点的亚硝酸根离子的荧光识别和选择性检测。

亚硝酸根离子（NO2-）是在自然生态系统和人体中都存在的重要无机物。高浓度的NO2-可能对动物和人类健康有害。重要的是开发一种简单，灵敏，可靠和经济的方法，以精确监控各种环境和生物领域中的NO2-。因此，使用伯芳基胺（PA），例如间苯二胺，通过高效的一锅水热法，构建并制备了基于碳量子点（PA-CD）的新型亚硝酸盐生物传感器。该器件在水中显示出鲜绿色的荧光，并具有20.1％的高量子产率。此外，PA-CD还具有两个较宽的线性范围：0.05-1.0μM和1.0-50μM，检出限低至7.1 nM。经典的重氮反应首先通过伯芳基胺整合到PA-CD系统中，这赋予了该系统高灵敏度和对亚硝酸盐的比选择性。重要的是，纳米传感器可以检测具有高荧光回收率的环境水和血清样品中的NO2-，证明了其在实际应用中的可行性。这项工作拓宽了一种新的方法来制造新型的纳米传感器，并为荧光碳量子点（CD）提供了前瞻性的应用。图形概要。这项工作拓宽了一种新的方法来制造新型的纳米传感器，并为荧光碳量子点（CD）提供了前瞻性的应用。图形概要。这项工作拓宽了一种新的方法来制造新型的纳米传感器，并为荧光碳量子点（CD）提供了前瞻性的应用。图形概要。