Corrigendum to "Polythiophene-Chitosan Magnetic Nanocomposite as a Highly Efficient Medium for Isolation of Fluoxetine from Aqueous and Biological Samples".

[This corrects the article DOI: 10.1155/2016/2921706.].

Modified Magnetic Nanoparticles as a Novel Sorbent for Dispersive Magnetic Solid-Phase Extraction of Triazine Herbicides in Aqueous Media.

In this study, a polythiophene/chitosan polymer and electrospinning polymer nanofibers as modifier compounds were used, and magnetic nanocomposites as a novel adsorbent were proposed, for the preconcentration of some triazines, including atrazine, ametryn, and terbutryn, in aqueous samples before GC. The synthesized magnetic nanoparticles, magnetic polymer nanofibers, and polythiophene magnetic nanocomposite were characterized by scanning electron microscopy. The separation of the target analytes from the aqueous solution containing the triazines and different magnetic nanocomposites were simply achieved by applying an external magnetic field. The extraction efficiency of magnetic polyamide nanofibers was enhanced as compared with other modified magnetic nanoparticles. The main factors affecting the extraction efficiency, including desorption conditions, nanocomposite component ratio, electrospinning time, sorbent amount, extraction time, ionic strength, and sample pH, were optimized. The developed method proved to be convenient and offers sufficient sensitivity and good reproducibility. Under optimized conditions, the method's LOD (S/N = 3) and LOQ (S/N = 10) were 1-5 and 15 ng L-1, respectively; good linearity was obtained within the range of 15-2000 ng L-1 for triazines, with correlation coefficients >0.9997. The RSD at the concentration level of 100 ng L-1 was 9-14% (n = 3). Furthermore, the method was successfully applied to the determination of triazines in real samples, in which relative recoveries of 98-103% were obtained. Compared with other methods, the current method is characterized by its ease, fast separation, and low detection limits.

Electrospun decyl-3-methylimidazolium mono bromate/polyamide nanofibers as solid-phase microextraction coating.

In the current study, electrospun-based ionic liquid (IL) doped polyamide (PA) nanofibers were prepared and used as the coating material of solid phase microextration device in the fiber geometry. Addition of IL, decyl-3-methylimidazolium mono bromate, increased the conductivity of the PA solution facilitating the electrospining process. The scanning electron microscopy images of decyl-3-methylimidazolium mono bromated/polyamide nanofibers showed the decreased diameter of the nanofibers in the range of 35-160nm compared to the PA nanofiber. The factors affecting the structure of nanofibers (e.g. ratio of decyl-3-methylimidazolium mono bromate to PA, coating time and applied voltage) were studied. In addition, influential parameters of extraction/desorption performance such as ionic strength, extraction time, and desorption time and temperature were studied. The limit of detections and limit of quantifications were obtained in the range of 0.75-0.9 and 2-5ngL-1, respectively, demonstrating high efficiency of the prepared nanofiber. The developed method also showed good repeatability, RSD 4-9% (n=3), for the spiked aqueous solution at concentration level 150ngL-1 of chlorobenzenes, and linearity,R=0.996, in the range of 5-5000ngL-1.

Composite Magnetic Nanoparticles (CuFe2O4) as a New Microsorbent for Extraction of Rhodamine B from Water Samples.

In this work, novel composite magnetic nanoparticles (CuFe2O4) were synthesized based on sol-gel combustion in the laboratory. Next, a simple production method was optimized for the preparation of the copper nanoferrites (CuFe2O4), which are stable in water, magnetically active, and have a high specific area used as sorbent material for organic dye extraction in water solution. CuFe2O4 nanopowders were characterized by field-emission scanning electron microscopy (SEM), FTIR spectroscopy, and energy dispersive X-ray spectroscopy. The size range of the nanoparticles obtained in such conditions was estimated by SEM images to be 35-45 nm. The parameters influencing the extraction of CuFe2O4 nanoparticles, such as desorption solvent, amount of sorbent, desorption time, sample pH, ionic strength, and extraction time, were investigated and optimized. Under the optimum conditions, a linear calibration curve in the range of 0.75-5.00 µg/L with R2 = 0.9996 was obtained. The LOQ (10Sb) and LOD (3Sb) of the method were 0.75 and 0.25 µg/L (n = 3), respectively. The RSD for a water sample spiked with 1 µg/L rhodamine B was 3% (n = 5). The method was applied for the determination of rhodamine B in tap water, dishwashing foam, dishwashing liquid, and shampoo samples. The relative recovery percentages for these samples were in the range of 95-99%.

Polythiophene-Chitosan Magnetic Nanocomposite as a Highly Efficient Medium for Isolation of Fluoxetine from Aqueous and Biological Samples.

Polythiophene/chitosan magnetic nanocomposite as an adsorbent of magnetic solid phase extraction was proposed for the isolation of fluoxetine in aqueous and biological samples prior to fluorescence detection at 246 nm. The synthesized nanoparticles, chitosan and polythiophene magnetic nanocomposite, were characterized by scanning electron microscopy, FT-IR, TGA, and EDAX. The separation of the target analyte from the aqueous solution containing the fluoxetine and polythiophene/chitosan magnetic nanocomposite was simply achieved by applying external magnetic field. The main factors affecting the extraction efficiency including desorption conditions, extraction time, ionic strength, and sample solution pH were optimized. The optimum extraction conditions were obtained as 10 min for extraction time, 25 mg for sorbent amount, 50 mL for initial sample volume, methanol as desorption solvent, 1.5 mL for desorption solvent volume, 3 min for desorption time, and being without salt addition. Under the optimum conditions, good linearity was obtained within the range of 15-1000 µg L(-1) for fluoxetine, with correlation coefficients 0.9994. Furthermore, the method was successfully applied to the determination of fluoxetine in urine and human blood plasma samples. Compared with other methods, the current method is characterized with highly easy, fast separation and low detection limits.