Development of fluorescence nanosensor based on “off-on” effect of graphitic carbon nitride - gold nanoparticles system for amikacin quantification

A graphitic carbon nitride functionalized gold nanoparticles (g-C3N4/AuNPs) based fluorometric assay was developed for simple and rapid on-site amikacin determination. g-C3N4 fluorescence is reduced (turn-off) when they bind to AuNPs but recovers (turn-on) when amikacin binds to AuNPs and releases the g-C3N4. The assay is based on the effective property of AuNPs as absorbers in inner filter effect (IFE) systems. Under optimized conditions of 25 mM Na2SO4, pH 6.0, 3.0 mg mL−1 g-C3N4, and incubation time of 12 min, the proposed method achieved a low detection limit of 5 × 10−9 M (2.9 ppb), wide linear range from 10−8 to 10−6 M, high precision (RSD