N-Allyl-4-(N-2′-hydroxyethyl)amino-1,8-naphthalimide as a fluorophore for optical chemosensing of nitrofurantoin

Abstract

N-Allyl-4-(N-2′-hydroxyethyl)amino-1,8-naphthalimide (AHEAN), a naphthalimide derivative, was synthesized as a new fluorophore for optical chemical sensor preparation. To prevent leakage of the fluorophore, AHEAN was photo-copolymerized with 2-hydroxypropyl methacrylate on a glass surface treated with a silanizing agent. An optical chemical sensor based on AHEAN can be utilized for nitrofurantoin assay based on fluorescence quenching. The sensor shows sufficient repeatability, selectivity and a fast response of less than 30 s. Nitrofurantoin can be determined in the range between 1.00 × 10⁻⁶ and 1.00 × 10⁻³ mol l⁻¹ with a detection limit of 4.8 × 10⁻⁷ mol l⁻¹. Most commonly co-existing drug substances and ions do not interfere with the nitrofurantoin assay. The sensor was applied to the analysis of pharmaceutical and urine samples.