Selective Fluorescence Detection of Glyphosate Pesticide Residue Based on Fe³⁺ Modulated SiQDs Nanosensors

In this paper, SiQDs were synthesized using 3-aminopropyltrimethoxysilane, an organosilicon source, via the room temperature stirring method under atmospheric pressure. Based on the "Turn-off" and "Turn-on" fluorescence response mechanisms, the SiQDs/Fe³⁺ fluorescent probe was constructed to quantitatively detect glyphosate according to the interaction between Fe³⁺ and glyphosate. Subsequently, the impacts of pH, incubation temperature, and reaction time on the detection of glyphosate were systematically investigated. Under the optimized detection parameters, the fluorescent probe exhibited a linear range of 2-10 μg/mL and a detection limit of 394.74 ng/mL. The constructed fluorescent probe demonstrated outstanding anti-interference performance. It was applied to actual samples of potato and yam, yielding satisfactory detection results with recovery values between 91.69% and 104.53%. These findings provide novel ideas and theoretical support for glyphosate residue detection.