Fe3O4@ionic liquid-β-cyclodextrin polymer magnetic solid phase extraction coupled with HPLC for the separation/analysis of congo red

Fe 3 O 4 @ionic liquids β-cyclodextrin polymer(Fe 3 O 4 @mono-6-deoxy-6-(1-ethyl-imidazolium)-β-cyclodextrin iodide polymer, Fe 3 O 4 @ILs-β-CDCP) was prepared. Magnetic solid phase extraction coupled with high-performance liquid chromatography for the separation/analysis of congo red (CR) in water and drysaltery was established. Fe 3 O 4 @ILs-β-CDCP showed a higher adsorption capacity toward CR. CR was adsorbed rapidly by Fe 3 O 4 @ILs-β-CDCP (adsorption efficiency: 95%) and eluted by ethanol (elution efficiency: 96%) at room temperature. Under the optimal conditions, preconcentration factor of the proposed method was 20-fold. The linear range, correlation coefficient ( R 2 ), detection limit (DL) and relative standard deviation were found to be 0.005–100.00 µg mL −1 , 0.9910, 1.8 g L −1 and 0.61% ( n  = 3, c  = 5.00 µg mL −1 ), respectively. The adsorption mechanism of CR on Fe 3 O 4 @ILs-β-CDCP was studied through the FTIR analysis. The accuracy of the developed method was confirmed by spiking city water, lake water, pond water and drysaltery. Fe 3 O 4 @ILs-β-CDCP can be used repeatedly for 10 times. This proposed method had been successfully applied to the determination of CR in real samples.