Determination of nitrofurans in feeds based on silver nanoparticle-catalyzed chemiluminescence

Abstract

A highly sensitive chemiluminescence (CL) method for the determination of nitrofurans (NFs) was developed based on the enhancement of CL intensity of luminol–H 2O 2–NFs system by silver nanoparticles (AgNPs). It was supposed that the oxygen-related radicals of OH and superoxide radical (O 2 − ) could be produced when NFs reacted with H 2O 2. Furthermore, the enhancement mechanism was originated from the reinforcer of AgNPs, which could catalyze the generation of the OH radical. Then OH radicals reacted with luminol anion and HO 2 − to form luminol radical (L − ) and O 2 − . The excited state 3-aminophthalate anion was obtained in the reaction of L − and O 2 − , which was the emitter (luminophor) in the luminol–H 2O 2 CL reaction system and the maximal emission of the CL spectrum was at 425 nm. The experiments of scavenging oxygen-related radicals were done to confirm these reactive oxygen species participated in the CL reaction. The limits of detection (LOD) ( S/ N=3) were 8×10 −7 g mL −1 for furacilin, 8×10 −8 g mL −1 for furantoin, 4×10 −8 g mL −1 for furazolidone and 2×10 −7 g mL −1 for furaltadone. The proposed method was successfully applied to the determination of NFs in feeds and pharmaceutical samples.