Abstract
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-β-cyclodextrin polymer magnetic particles Fe3O4 functionalized with ionic liquid (IL-CM-HP-β-CDCP magnetic nanoparticles (MNPs)) was developed for a selective separation of linuron prior to its determination by UV-visible spectrometry. Ionic liquid modified carboxymethyl-hydroxypropyl-β-cyclodextrin polymer magnetic particles Fe3O4 (Fe3O4@IL-CM-HP-β-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-β-CDCP MNPs adsorbent toward linuron was studied. The concentrations of linuron were directly determined after reading absorbance by UV-visible spectrometry. Fourier transform infrared spectroscopy, scanning electron microscopy, and XRD results strongly confirmed the formation of Fe3O4@IL-CM-HP-β-CDCP MNPs phase. Adsorption study revealed the Fe3O4@IL-CM-HP-β-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-β-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 μg mL−1 with a relative standard deviation of 1.97 % (n = 3, c = 4.00 μg mL−1). The detection limits, the limit of quantification, correlation coefficient (R), and preconcentration factor were 7.0 μg L−1, 70.0 μg L−1, 0.9987, and 15, respectively. Ultimately, the developed method can be applied and effectively utilized for the determination of linuron in real samples.
Highlights
Direct determination of trace analyte, in particular at ultra-trace concentration, cannot be achieved in complex systems by UV-visible spectrometry because of the lack of sensitivity and selectivity of the method
The direct determination with spectrophotometry for linuron is difficult owing to matrix effects and its lower concentration in natural samples
The results are as follows: (1) the peak of 580 cm−1 showed was assigned to Fe-O-Fe stretching vibration, the peak of 2400 and 2850 cm−1 on curve b corresponded to the C-H stretching vibration in CM-HP-β-CDCP, and the peaks at 1628 cm−1 on curve b was stronger than on curve a, which illustrated that CM-HP-β-CD was coated Fe3O4 surface; (2) in the curve c, the peaks at 3171 and 3125 cm−1 embody the spectrum of the C-H stretching vibration, the peaks at 1573 and 1462 cm−1 corresponded to the characteristic absorption of imidazole groups, and 739 cm−1 corresponded to long chain CH2; the peak of 840 cm−1 was attributed to the P-F stretching vibration
Summary
Direct determination of trace analyte, in particular at ultra-trace concentration, cannot be achieved in complex systems by UV-visible spectrometry because of the lack of sensitivity and selectivity of the method. A new magnetic solid phase extractor based on ionic liquid modified carboxymethyl-hydroxypropyl-β-cyclodextrin polymer magnetic particles Fe3O4 functionalized with ionic liquid (IL-CM-HP-β-CDCP magnetic nanoparticles (MNPs)) was developed for a selective separation of linuron prior to its determination by UV-visible spectrometry. Linuron (Fig. 1) is one of the urea herbicides; it was developed by the DuPont as urea herbicides in 1960 and was widely used in agricultural production (Lima et al 2011). It could exist in environment stably for a long time and pollute the soil and surface water, seriously damaging the groundwater and organisms (Ornostay et al 2013). UV spectrometry is often combined with separation/enrichment technique to improve the selectivity and sensitivity of detection (Chen and Zhu 2015)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
