Powder microelectrode embedded with carboxyl multi-walled carbon nanotubes for sensitive and quantitative detection of nitrofuran residues

Abstract

In this study, a sensitive electrochemical detection method for nitrofurazone (NF) and semicarbazide (SC) based on a powder microelectrode embedded with carboxyl multi-walled carbon nanotubes was developed. The carboxyl groups were introduced to the multi-walled carbon nanotubes (MWCNTs) to increase the surface holes, which improve the MWCNTs’ electrocatalytic properties. Compared with traditional electrodes, the powder microelectrode (PME) has a small diameter. Therefore, it needs less time to complete the detection process. Under optimal experimental conditions, the obtained PME presented a linear response to NF in the range of 1 × 10⁻⁶ to 5 × 10⁻³ mol L⁻¹ with a detection limit of 6.45 × 10⁻⁷ mol L⁻¹. The linear range of SC was 2 × 10⁻⁶ to 1 × 10⁻³ mol L⁻¹ with a detection limit of 1.18 × 10⁻⁷ mol L⁻¹. The recoveries of NF and SC were 91.00–105.00% and 96.00–109.00%, respectively. The sensor could feasibly and successfully be used for the detection of nitrofuran drugs and their residues.