Background:
As a broad-spectrum antibiotic of the sulfonamide family, Sulfadimethoxine
(SDM) has been widely utilized for therapeutic and growth-promoting purposes in animals. However,
the use of SDM can cause residual problems. Even a low concentration of SDM in the aquatic
system can exert toxic effects on target organisms and green algae. Therefore, the quantitation of
SDM residues has become an important task.
Methods:
The present work describes the development of a sensitive and selective electrochemical
sensor for sulfadimethoxine based on molecularly imprinted poly(o-aminophenol) film. The
molecular imprinted polymer film was fabricated by electropolymerizing o-aminophenol in the presence
of SDM after depositing carboxylfunctionalized multi-walled carbon nanotubes onto a glassy
carbon electrode surface. SDM can be quickly removed by electrochemical methods. The imprinted
polymer film was characterized by cyclic voltammetry, differential pulse voltammetry and scanning
electron microscopy.
Results:
Under the selected optimal conditions, the molecularly imprinted sensor shows a linear
range from 1.0 × 10-7 to 2.0 × 10-5 mol L-1 for SDM, with a detection limit of 4.0 × 10-8 mol L-1. The
sensor was applied to the determination of SDM in aquaculture water samples successfully, with the
recoveries ranging from 95% to 106%.
Conclusion:
The proposed sensor exhibited a high degree of selectivity for SDM in comparison to
other structurally similar molecules, along with long-term stability, good reproducibility and excellent
regeneration capacity. The sensor may offer a feasible strategy for the analysis of SDM in aquaculture
water samples.
