New magnetic solid phase extractor based on ionic liquid modified beta-cyclodextrin polymer/Fe3O4 nanocomposites for selective separation and determination of linuron

Background: Direct determination of trace analyte, in particular at ultra-trace concentration, cannot be easily achieved in complex systems by UV-visible spectrometry because of the lack of sensitivity and selectivity of the method. Therefore, an efficient separation step is often required prior to the determination. In accordance, a new magnetic solid phase extractor based on ionic liquid modified carboxymethyl-hydroxypropyl-beta-cyclodextrin polymer magnetic particles Fe3O4 functionalized with ionic liquid (IL-CM-HP-beta-CDCP magnetic nanoparticles (MNPs)) was developed for a selective separation of linuron prior to its determination by UV-visible spectrometry. Methods: Ionic liquid modified carboxymethyl-hydroxypropyl-beta-cyclodextrin polymer magnetic particles Fe3O4 (Fe3O4@IL-CM-HP-beta-CDCP) were confirmed by Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray powder diffraction (XRD). The uptake behavior of the new Fe3O4@IL-CM-HP-beta-CDCP MNPs adsorbent toward linuron was studied. The concentrations of linuron were directly determined after reading absorbance by UV-visible spectrometry. Results: Fourier transform infrared spectroscopy, scanning electron microscopy, and XRD results strongly confirmed the formation of Fe3O4@IL-CM-HP-beta-CDCP MNPs phase. Adsorption study revealed the Fe3O4@IL-CM-HP-beta-CDCP MNPs for a selective separation of linuron prior to its determination by UV-visible spectrometry. The results showed that linuron was adsorbed rapidly on Fe3O4@IL-CM-HP-beta-CDCP MNPs and eluted by 4.0 mL ethanol in 15 min. Under the optimized conditions, the linear calibration curves for linuron were obtained over the concentration range of 0.07-19.00 mu g mL(-1) with a relative standard deviation of 1.97 % (n = 3, c= 4.00 mu g mL(-1)). The detection limits, the limit of quantification, correlation coefficient (R), and preconcentration factor were 7.0 mu g L-1, 70.0 mu g L-1, 0.9987, and 15, respectively. Conclusions: Ultimately, the developed method can be applied and effectively utilized for the determination of linuron in real samples.