Rapid detection method for nitrofuran antibiotic residues by surface-enhanced Raman Spectroscopy

Abstract

Nitrofurans are a group of widely used veterinary antibiotics which have been forbidden in many countries. Surface-enhanced Raman spectroscopy (SERS) coupled with gold nanoparticles was used in this study for the rapid detection and characterization of nitrofuran antibiotics (including furadantin, furaltadone, and their mixture). Density functional theory calculations were conducted with Gaussian 03 at the B3LYP level using the 6-31G(d) basis set to analyze the assignment of vibrations. The SERS measurement of nitrofuran antibiotics has been investigated by active SERS substrate of gold nanoparticles with average size around 50 nm. The SERS qualitative analysis has been studied for furadantin and furaltadone by their characteristic SERS peaks. The peaks at 1,420 and 1,456 cm−1 could be used to discriminate between the two compounds in a mixture. The SERS peaks at 1,008 and 1,162 cm−1 were used as the index of quantitative analysis for furadantin and furaltadone, respectively. Under optimal conditions, the limit of detection could reach the level of 5 ppm. The results showed that the SERS method with gold nanoparticles is capable of identifying and characterizing furaltadone and furadantin, which is valuable to be further applied on the detection of antibiotic residues in food samples.