Carbon dots-functionalized aerogel sensor for fluorescent and portable monitoring of organic peroxides

Organic peroxides in foodstuffs like lipid hydroperoxides and benzoyl peroxide (BPO) have risks to human health, which need rapid and on-site determination. This study prepared hydrophobic and reductive fluorescent iodine-doping carbon dots (I-CDs) via a solvothermal strategy using oleylammonium iodide as the precursor. The I-CDs can be used as nanoprobes to rapidly and sensitively determine organic peroxides. Organic peroxides can oxidize the I-CDs to produce I₂, which can efficiently quench their fluorescence through the inner filter effect. Furthermore, hydrophobic aerogels were prepared to incorporate the I-CDs, constructing a fluorescent sensor. When combined with a smartphone and portable detection equipment, the developed sensor enables rapid on-site testing of peroxide values (PVs) in edible oils, as well as BPO in flour. The fluorescent sensor has a detection limit of 1.2 mmol/kg for PVs and 0.10 mmol/kg for BPO. Our study provides an efficient tool for monitoring organic peroxides in foodstuffs.