A nanocomposite optosensor of hydroxyapatite and graphene quantum dots embedded within highly specific polymer for norfloxacin detection

A nanocomposite fluorescent probe was developed for the detection of norfloxacin. The fluorescent nanoprobe was fabricated by incorporating hydroxyapatite and graphene quantum dots into a highly selective polymer. The fabrication procedure, detection system and analytical performance of the nanoprobe were optimized for norfloxacin detection. Quenching of the emission intensity of the fluorescent nanoprobe was linear from 1.0 to 100.0 mu g L-1 of norfloxacin. The limit of detection was 0.35 mu g L-1. The fluorescent nanoprobe exhibited an excellent specificity for norfloxacin with a high imprinting factor of 68.7. Applied to detect norfloxacin in chicken meat and milk, the optosensor achieved recoveries between 93.8 and 99.3%. Precision was good with RSD below 6%. Hydroxyapatite enhanced the adsorption of norfloxacin on the probe, graphene quantum dots improved the sensitivity of the sensing response and the molecularly imprinted polymer increased the specificity of the probe. The fabricated optosensor was simple to prepare and detection was rapid with excellent sensitivity and selectivity.