Sustainable N-CQDs from Phyllanthus emblica: A dual-function fluorescent probe for chloramphenicol detection and latent fingerprint enhancement

Selective and sensitive detection of chloramphenicol (CAP) in food and environmental samples was achieved through green-synthesis of nitrogen-doped carbon-quantum-dots (N-CQDs) from Phyllanthus emblica. Green-technique employs a microwave-assisted-approach that is founded on green chemistry principles to produce N-CQDs with enhanced photoluminescence through N-doping. Structural characterization of samples confirmed their effective nitrogen incorporation, spherical-characterization (average-diameter: 6.49 nm), and graphitic-structure. N-CQDs exhibit robust quenching response to CAP and remarkable fluorescence-stability, with a linear-detection-range of 0.5–25 μM and detection limit of 13.1 nM. Probe's specificity is demonstrated by its resistance to interference from other antibiotics, including tetracycline and amoxicillin. Process demonstrated practical utility by achieving recovery rates of 98.13 %–105.33 % in real-world matrices such as milk, yogurt, effluent, and agricultural runoff on application. Additionally, silica nanocomposite phosphors were combined with N-CQDs for the purpose of conducting a forensic investigation. Unique luminous qualities of N-CQDs enabled the visualization of latent fingerprints in a more detailed manner, which in turn revealed distinct ridge patterns under UV illumination. This combined action demonstrates the relevance of N-CQDs in overcoming the primary obstacles in environmental monitoring, forensic science, and food safety. Additionally, this approach is reasonably priced and scalable, which suggests that it has potential for widespread application.