Fluorescent and visual detection of norfloxacin in aqueous solutions with a molecularly imprinted polymer coated paper sensor

A dual functional molecularly imprinted polymer (MIP) coated paper (MIP-CP) sensor was firstly proposed for rapid fluorescent (FL) and visual analysis of norfloxacin (NOR) in aqueous solutions. The sensor was fabricated via a sol-gel technique, and characterized by FTIR and SEM. The extraction capacity, selectivity, detection limit, and linear range of the MIP-CP sensor were studied by an FL spectrophotometer. The modified paper sensor showed good selectivity and high extraction capacity for NOR and its structural analogues. For FL analysis of NOR, the linear range and detection limit were found to be 10-100 ng/ml and 2.59 ng/ml, respectively. The visual determination of NOR (under UV light) based on the MIP-CP sensor was also explored, and the determination limit was found to be 0.1 μg/ml. Finally, the proposed methods were successfully applied to the direct determination of NOR in pharmaceutical preparations and cross-validated by UPLC. The MIP-CP sensor might be a potential platform for antibiotic determination due to its multifunction and good analytical performance.