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In the present work, reusable magnetic molecularly imprinted polymers have been used for the first time as an adsorbent for the determination of chlorferon. Magnetic molecularly imprinted polymers have been used for the selective separation of chlorferon from the solution and sensitive fluorimetric determination has been performed using the native fluorescence of chlorferon. The developed method is rapid and determination of chlorferon was completed in an hour. Limit of detection (LOD) of the method was found to be 0.0027 mu M and the linearity of the calibration graph was observed within the range of 0.01-0.36 mu M (2.5 - 75 mu g L-1). Adsorption isotherms point out the multilayer adsorption and the heterogeneous distribution of binding sites for imprinted polymer and homogeneous binding site for non-imprinted polymer. The adsorption capacities of imprinted polymer and non-imprinted polymer were calculated as 2.03 mu mol g(-1) and 0.96 mu mol g(-1), respectively and the imprinting factor was found to be 2.11. The interference effects of some organic compounds and characterization studies were also evaluated. The method has been applied to honey and tap water samples and the recoveries were found to be in the range of 91.3 and 101.1 %., 18-EGEMATAL-003, 18-EGEMATAL-003.

In this paper, magnetic-molecularly imprinted polymer was used for the preconcentration of trace levels of imidacloprid in water and apple samples prior to liquid chromatography-quadrupole-time-of-flight mass spectrometric determination. The selectivity of the magnetic polymer was united with the sensitivity and the high resolving power of the chromatographic system. The developed method showed a linear range from 10.0 to 500.0 mu g/L. The quantitative recoveries were obtained for water and apple samples in the range of 92.0%-99.0 %. The relative standard deviations of intra-day and inter-day tests were found to be in the range of 0.8%-1.2% and 1.2%-1.6 %, respectively. In addition, the same magnetic-molecularly imprinted polymer (MMIP) can be used at least ten cycles for the determination of imidacloprid. The preconcentration factor of the method was found to be 2.5, and the total preconcentration procedure can be completed in 1 h. Characterization of synthesised particles were executed with various techniques. Due to its suitable limit of detection, dynamic linear range, sensitivity and selectivity, the developed method seemed to be ideal for the determination and preconcentration of imidacloprid in water and fruit samples., Research Fund of Ege University [18 -EGE-MATAL -003], This work was supported by Research Fund of Ege University for financial support (Grant no: 18 -EGE-MATAL -003).

Optical sensors based on UV-visible absorption, fluorescence, phosphorescence, chemiluminescence, surface plasmon resonance, and surface-enhanced Raman scattering techniques are widely used to detect trace levels of pesticides. Generally, molecularly imprinted polymers have been used as selective adsorbent and the recognition unit of the optical sensors in pesticide analysis. Due to the combination of the selectivity of the molecularly imprinted polymers with the sensitivity of the detection techniques, molecularly imprinted polymer-based optical sensors take an important place in pesticide analysis. This chapter aims to highlight the usage of different types of molecularly imprinted polymer-based optical sensors designed for the determination of pesticides. © 2021 Elsevier Inc.

Stabilization of biomolecules on matrices is critically important. Here we constructed composite nanofibers with magnetic features by electro-spinning of magnetic nanoparticles (MNP) in an appropriate polymer matrix on a collector surface for multiple uses. 'Poly(vinylalcohol)-polyethyleneimine/Fe3O4 magnetic nanoparticles' (PVA-PEI/MNP) composite nanofiber was used on the screen printed electrodes (SPE) to serve as a platform for the glucose oxidase (GOx) biofilm as the model biomolecule. To show the potential application of this material as a biosensor component, the resulted biofilm, called 'PVA-PEI/MNP/GOx', was fixed on SPE via a neodymium magnet for the electrochemical detection of glucose at -0.7 V where oxygen consumption due to enzymatic reaction was measured. The main advantage of the obtained magnetic biomembrane is that it allows analysis with a single drop. After step-by-step surface modifications, analytical characterization was performed using various techniques, such as voltammetry, electrochemical impedance spectroscopy, Fourier-transform infrared spectroscopy and X-Ray photoelectron spectroscopy as well as microscopic techniques. The linear range of the PVA-PEI/MNP/GOx surface was found as 0.0125 to 0.5 mM with a limit of detection of 11.5 mu M for glucose as analyte. The application of PVA-PEI/MNP/GOx for glucose detection in synthetic samples was carried out. Data proved the potential use of the 'PVA-PEI/MNP' surface as a biomolecule immobilization platform for disposable biosensor applications.

In this study, magnetite-molecularly imprinted polymer has been used for the first time as selective adsorbent before the fluorimetric determination of carbendazim. Adsorption capacity of the magnetite-molecularly imprinted polymer was found to be 2.31±0.63mgg-1 (n=3). Limit of detection (LOD) and limit of quantification (LOQ) of the method were found to be 2.3 and 7.8μgL-1, respectively. Calibration graph was linear in the range of 10-1000μgL-1. Rapidity is an important advantage of the method where re-binding and recovery processes of carbendazim can be completed within an hour. The same imprinted polymer can be used for the determination of carbendazim without any capacity loss repeatedly for at least ten times. Proposed method has been successfully applied to determine carbendazim residues in apple and orange, where the recoveries of the spiked samples were found to be in the range of 95.7-103%. Characterization of the adsorbent and the effects of some potential interferences were also evaluated. With the reasonably high capacity and reusability of the adsorbent, dynamic calibration range, rapidity, simplicity, cost-effectiveness and with suitable LOD and LOQ, the proposed method is an ideal method for the determination of carbendazim.

Pesticides are harmful compounds even in trace levels for human health, so the importance of determination of these compounds is increasing day by day. Magnetite-molecularly imprinted polymer and high resolution liquid chromatography has been combined for the preconcentration and sensitive and selective determination of trace levels of pirimicarb. the developed method appeared to be rapid since the total procedure for detection of pirimicarb can be completed within one hour. the magnetic polymer is reusable and the same polymer can be used at least ten cycles for detection of pirimicarb. Limit of detection (LOD) of the method was found to be 1.60 mu g L-1 within the linear range of 7.5-250 mu g L-1. Proposed method has been applied to water and apple samples and quantitative recovery values were obtained. the proposed method appeared to be suitable for both preconcentration and determination of trace levels of pirimicarb by combining the selectivity of the reusable imprinted polymer with the high sensitivity of liquid chromatography-quadrupole-time-of-flight mass spectrometry. Magnetite-molecularly imprinted polymer combined with high resolution chromatography has been used for the first time for the determination of pirimicarb., Research Fund of Ege UniversityEge University [18-EGEMATAL-003], This work was supported by Research Fund of Ege University for financial support [Grant no: 18-EGEMATAL-003].

A new nickel/nickel boride-based nanosorbent which provides high sorption efficiency for tin(IV) was developed in this study. The sorbent capacity was found to be 26.33 ± 2.18 mg tin(IV)/g sorbent (n = 3). Tin(IV) can be determined by measuring the fluorescence signal of the tin(IV)–flavonol complex. Recovery of tin(IV) with 1 mol/L hydrochloric acid was found to be 98.70 ± 1.29 (n = 5). The limit of detection and the limit of quantification of the method were found to be 0.5 and 1.7 µg/L, respectively. The calibration graph was linear in the range of 4–80 µg/L. The adsorption type was determined by using the adsorption isotherms. Interference effects of several metal ions on tin(IV) determination were investigated and the tolerable concentration limits of these metal ions were determined. The nickel/nickel boride nanosorbent reduces the interference effects and improves the sensitivity and the selectivity of the method. With the aid of the novel nanosorbent, higher tolerable concentration limits ...

A sensitive and selective method based on the determination of haloperidol with the usage of magnetite-molecularly imprinted polymer and high-resolution liquid chromatography has been developed. This novel method is rapid as the detection procedure for haloperidol can be completed within a total time of 1 h. The same imprinted polymer can be used for the determination of haloperidol at least 20 times. The proposed method has been succesfully applied to synthetic urine and serum samples and the recoveries of the spiked samples were in the range of 94.7-100.7%. The limit of detection and limit of quantification of the method were 2.25 and 7.50 μg/L, respectively. Linearity of the calibration graph was observed within the range of 10-250 μg/L. By combining the high capacity, high selectivity, and reusability of the magnetic adsorbent with the dynamic calibration range, high sensitivity and high resolution of liquid chromatography with quadrupole time-of-flight mass spectrometry, the proposed method is an ideal method for the determination and preconcentration of trace levels of haloperidol. A magnetite-molecularly imprinted polymer has been used for the first time as a selective adsorbent for the determination of haloperidol.

WOS: 000471333300009, PubMed: 30954798, In this study, a novel method based on the determination of 1-naphthalene acetic acid with the usage of magnetite-molecularly imprinted polymer prior to fluorimetric detection has been developed. Magnetite-molecularly imprinted polymer has been used for the first time as selective adsorbent for the determination of 1-naphthalene acetic acid. the adsorption capacity of the synthesized polymer was found to be 2.18 +/- 0.36 mg g(-1) (n = 3). Limit of detection (LOD) and limit of quantification (LOQ) of the method were found to be 0.75 and 2.50 mu g L-1, respectively. Linearity of the calibration graph for the proposed method was observed within the range of 20-700 mu g L-1. the proposed method seems to be rapid where the detection procedure for 1-naphthalene acetic acid can be completed within a total time of 1 h. the same imprinted polymer can be used for the determination of 1-naphthalene acetic acid with quantitative sorption and recovery values repeatedly for at least ten times. the effects of some potential organic interferences were investigated. Proposed method has been successfully applied to determine 1-naphthalene acetic acid in cucumber, where the recoveries of the spiked samples were found to be in the range of 93.7-104.5%. Characterization of the synthesized polymer was also evaluated. By combining the high capacity, cheapness, reusability and selectivity of the magnetic adsorbent with the dynamic calibration range, rapidity, simplicity, and sensitivity of fluorimetry, the proposed method seems to be an ideal method for the determination of trace levels of 1-naphthalene acetic acid. (c) 2019 Elsevier B.V. All rights reserved., Ege UniversityEge University [2018EGEMATAL002], We gratefully thank to Research Fund of Ege University for financial support (Grant no: 2018EGEMATAL002).

Studies have been carried out to clarify the mechanism of nickel interferences in the hydride generation atomic absorption spectrometric determination of arsenic and antimony. The most serious nickel interferences are observed when nickel/nickel boride nanoparticles are produced during NaBH 4 reduction. In this study these particles have been observed to have diameters of less than 40 nm and sorb As(III), As(V) and Sb(III) species rather than arsine and stibine generated as so far assumed. Bulk chemical composition and surface structure of these nanoparticles were studied and it was found that if the NaBH 4 reduction is carried out while passing nitrogen through the solution the black nanoparticles were composed of Ni 2 B and, if the reduction is carried out under air the black nanoparticles were found to consist of Ni 3 B or possibly a mixture of Ni(0) and Ni 2 B. Surface analysis studies with scanning electron microscopy, energy dispersive X-ray spectrometry, X-ray photoelectron spectrometry and X-ray diffraction analysis have shown that the particles have amorphous structure consisting of Ni(0), Ni 2 B, Ni 3 B and Ni(OH) 2 . However, sorption studies have shown that Ni(0) and Ni(OH) 2 do not sorb the analyte ions and arsine and stibine significantly.