Abstract: First, multi-wall carbon nanotubes (MWCNs) were modified on the screen printed electrode (SPE), and then molecularly imprinted membrane (MIM) and non-imprinted membrane (NIM) were directly synthesized on the modified SPE by using the in-situ thermal polymerization techniques, respectively. A conductometric sensor for the detection of ractopamine was assembled by connecting the SPE modified with MWCNs-MIM and the other one coated with MWCNs-NIM to a conductometer through an electrode slot. Standard calibration curve was established and the determination of ractopamine in pig urine samples also was performed based on this sensor. Superficial characteristic of MIM and NIM was investigated using scanning electron microscope (SEM). The results showed that there were number of imprinted micro-pores on the surface of MIM. The sensor showed high selectivity and specificity towards the target ractopamine. The response of the sensor to concentration of ractopamine displayed a linear correlation over a range from 0.33 to 8.0 mg/L with a detection limit of 0.033 mg/L. The recoveries were 91%-98% based on pig urine samples for the determination of ractopamine on sites.
Template and target information: ractopamine
Author keywords: Multi-walled carbon nanotubes, Ractopamine, molecularly imprinted membrane, conductometric sensor