Construction of nitrogen-doped carbon dots-europium ion coordination fluorescence sensing system for detection of pyridine-2,3-dicarboxylic acid

Abstract

This study synthesized nitrogen-doped carbon dots (CDs) via microwave heating method and constructed a fluorescence sensing system based on europium ion (Eu3+) coordination for efficient detection of pyridine-2,3-dicarboxylic acid (DPA). The experiment systematically investigated the effects of Eu3+ concentration and solution pH on the fluorescence behavior of CDs: as the Eu3+ concentration increased from 25 μL to 200 μL, the blue light emission intensity of CDs exhibited concentration-dependent quenching, with optimal quenching efficiency at 200 μL Eu3+ solution pH significantly affected the system’s fluorescence intensity, with pH = 8 determined as the optimal working pH for DPA detection, where CDs and Eu3+ coordinate most effectively. The CDs-Eu3+ fluorescence sensing system constructed in this study combines advantages of simple operation, environmental friendliness, and high sensitivity, providing a new strategy for rapid quantitative detection of DPA.