Nitrogen-doped carbon quantum dots from biomass as a FRET-based sensing platform for the selective detection of H2O2 and aspartic acid

Abstract

Hydrogen peroxide (H₂O₂) with strong oxidizing properties and a volatile nature has a potential role in biological systems and industrial applications. Developing an optical “on–off–on” probe for the efficient detection of H₂O₂ is crucial for health, environmental safety, and diagnostic applications. Herein, sustainable N-doped carbon quantum dots (N-CQDs) were explored as optical probes for the selective discrimination of H₂O₂ and aspartic acid in aqueous media based on simple photoluminescence “turn on” and “turn off” mechanisms. N-CQDs were synthesized from Moringa oleifera (drumstick leaves) used as both a carbon and nitrogen source. The synergistic effect of N-doping, oxygenous surface functional groups and structural advantages lead to high selectivity and good sensing performance with a LOD value of 26.4 mM and 134.2 nM for H₂O₂ and aspartic acid, respectively. The simple synthesis process and structural advantage of N-CQDs showed the potential for the detection of reactive oxygen species and biomolecules with high sensitivity and selectivity in an aqueous medium for diagnostic applications and human health monitoring.