Simultaneous detection of Cu2+ and amoxicillin based on the copper and nitrogen-regulated fluorescent probe

A novel fluorescence-based probe represented as Cu, N-CDs, was developed for the dual sensing detection of Cu2+ and amoxicillin (AMO), which had a high quantum yield up to 60.08 %, along with excellent photoluminescent properties and remarkable stability. When detecting Cu2+, the fluorescence signal from Cu, N-CDs probe experienced quenching due to photoinduced electron transfer (PET). Subsequently, the introduction of AMO led to the recovery of the probe's fluorescence. This recovery was likely attributed to the superior affinity between Cu2+ and AMO, resulting in the displacement of Cu2+ from the Cu, N-CDs and blocked the PET process. Notably, the detection limits of Cu2+ and AMO were determined 18 nM and 9 nM, respectively. We further demonstrated the practical utility of the Cu, N-CDs probe through its successful application in the analysis of Cu2+ and AMO in Chinese herbal medicine and milk samples. Overall, our findings highlighted the potency of Cu, N-CDs as versatile and effective tools for the detection of Cu2+ and AMO, paving the way for their broad applications in the safety analysis of food and pharmaceutical.