Rapeseed oil residue-based fluorescent probes for bifunctional detection of Hg2+ and aureomycin hydrochloride

Rapeseed oil residue (ROR) is the waste product of rapeseed oil extraction, mainly including protein and lignocellulose. In this study, we utilized waste ROR as the raw material to successfully prepare blue fluorescent carbon dots (ROR-CDs) by self-propagating synthesis. It demonstrated rapid preparation (20 min) with low energy consumption (400 °C) and without complicated purification processes. We analyzed the structural and optical properties of ROR-CDs. ROR-CDs exhibited exceptional fluorescence performance and stabilized, responding specifically to divalent mercury ions (Hg 2+ ) and aureomycin hydrochloride (CTC). Thus, we developed a high-sensitivity detection technique with a detection range and limit of detection (LOD) for Hg 2+ of 0–250 μg/L and 191.69 ng/L, respectively. For CTC, the detection range and LOD were 0–50 μM and 12.7 nM (S/N = 3), respectively. It is easy to operate and low-cost, ensuring efficient assistance for testing efforts in associated domains. Additionally, ROR-CDs-based detection technique can analyze Hg 2+ and CTC in the actual samples, demonstrating significant potential for application in environmental monitoring and food safety assessment.