Background:
Multi-walled carbon nanotubes (MWCNT) adjunct to molecularly
imprinted polymers (MIP) have advantages of the large surface area of nanoparticles and
selectivity of MIPs for selective extraction of tetradifon as a widely used pesticide in date
palm.
Objectives:
The main aims were the use of experimental design, electrochemical synthesis
and ultra-high performance liquid chromatography (UHPLC) to develop a simple, reliable
and precise pesticide residue analysis method as an important aspect of food and drug quality
control for the determination of tetradifon in date palms.
Methods:
An MIP in the presence of MWCNT was synthesized by cyclic voltammetric
technique on a steel rod to produce a composite of MIP-MWCNTs for stir bar extraction of
tetradifon residue in date samples. The experimental design was used to optimize MIPMWCNT
composite synthesis through the screening of eight variables. The composite was
characterized by scanning electron microscopy (SEM). Tetradifon was determined in extracted
samples by UHPLC under optimum conditions.
Results:
A very thin film was made by MIP-MWCNT coated on a steel rod which was repeatable
and had good adhesion and persistence. The detection limit (LOD) and the quantification
limit (LOQ) of the method were measured as 16 and 49 ng/ml, respectively. Average
recovery of tetradifon at the two spiked levels was observed to be as low as 86.5% to
90.7% (RSD from 0.79% to 1.04%).
Conclusion:
The low cost, high selectivity, good reproducibility, acceptable intra and inter
day precision and accuracy developed method were successfully applied to determine
tetradifon residue in date samples purchased from a local market.
