Water-soluble luminescent nitrogen-doped CDs (N-CDs) having a high QY of 29.83% were prepared by a one-step microwave-assisted pyrolysis method using ammonium citrate and triethylenetetramine as the precursors. The microstructure, optical properties and biocompatibility of the N-CDs were investigated. Results indicate that they exhibit a strong fluorescence, favorable biocompatibility and excellent optical stability. Their photoluminescence is quenched by Cu²⁺ ions through the formation of a complex between the N-CDs and Cu²⁺, which can be used for Cu²⁺ detection. Compared with other CD-based nanomaterials, the N-CDs show outstanding optical properties, and excellent selectivity and sensitivity for Cu²⁺ detection with a linear range of 0.01-11 μM and a detection limit of 4.5 nM. The selectivity for Cu²⁺ detection is so good that the N-CDs have been successfully used in Cu²⁺ detection for real water samples. They have also been used to draw fluorescent patterns and image living cells.

使用柠檬酸铵和三亚乙基四胺作为前体，通过一步微波辅助热解法制备了具有29.83％高QY的水溶性发光氮掺杂CD（N-CD）。研究了N-CD的微观结构，光学性质和生物相容性。结果表明它们显示出强荧光，良好的生物相容性和优异的光学稳定性。它们的光致发光通过在N-CD和Cu ²⁺之间形成络合物而被Cu ²⁺离子淬灭，该络合物可用于Cu ²⁺检测。与其他基于CD的纳米材料相比，N-CD具有出色的光学性能，并且对Cu ²⁺具有出色的选择性和敏感性。线性范围为0.01-11μM的检测限和4.5 nM的检测限。Cu ²⁺检测的选择性非常好，以至于N-CDs已成功用于实际水样品的Cu ²⁺检测中。它们也已用于绘制荧光图案和图像活细胞。