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Macroporous polymeric gels has received great attention in many fields focused on biotechnological applications. In this study, two new HEMA-based cryogel columns were synthesized. To this end, poly(HEMA-VF) and poly(HEMA-NVP) cryogels were prepared by copolymerization of 2-Hydroxyethyl methacrylate (HEMA) with N-vinylformamide (VF) and N-vinylpyrrolidone (VP) in the presence of N,N-methylenebisacrylamide (as cross-linker), then polymerization initiated by ammonium persulfate (APS) and N,N,N ',N '-tetramethylenediamine (TEMED) with free-radical polymerizations method in cryogelation conditions, respectively. p(HEMA-VF) and p(HEMA-VP) cryogels contain a continuous polymeric matrix with interconnected pores of size 2-100 mu m. Swelling behavior for these cryogels in various solvents was investigated, wherein the characterization of the cryogels is conducted via by surface area measurement (BET), Fourier transforms infrared spectroscopy (FT-IR), elemental analysis, scanning electron microscopy (SEM), Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). As drug model compounds, Methyl Red (MR), methylene blue (MB) and methylene green (MG) were loaded into prepared cryogels and the controlled release properties of cryogel columns were examined comparatively each other. It has been shown that approximately 90% of its release from the cryogels occurred within about 2 h. In addition, MB release from p(HEMA-VF) and p(HEMA-VP) cryogels was found to be around 80% over a similar period. The proposed cryogels can be regarded as controlled release system on future biomedical applications. Duzce University Research FundDuzce University [2019.05.03.1024] This work was supported financially by the Duzce University Research Fund (Grant Number 2019.05.03.1024). WOS:000614319600001 2-s2.0-85100293367

In the present study, the enantiomeric forms of hydrophobic amino acids ( l -tryptophan, l -tyrosine, and l -phenylalanine) were separated by molecularly imprinted capillary columns (MICC) via Capillary Electrochromatography (CEC) for the first time. The monomer ratio, crosslinker ratio, template molecule ratio, the porogen ratio and type, polymerization time, and also the effect of temperature were examined to increase the permeability properties of MICC. FTIR, SEM and BET analyses were realized for the characterization of MICC. The effect of the electric field, organic solvent ratio, and pressure were carried out experimentally to determine the optimum conditions. The separation performances of MICC and the non-imprinted capillary columns (NICC) were compared electrochromatographically.

Sarkaya, Koray/0000-0003-0177-5134 WOS: 000487100600013 In the present study, a novel ion-imprinting and non-imprinting cryogel samples have been prepared using ion-imprinting technique and the dielectric properties have been investigated using an impedance spectroscopy method. In the preparation of ion-imprinted cryogel, at the first attempt, N-methacryloly-(l)-cysteine methyl ester was used as the metal complexing monomer. Ag+-imprinted poly(hydroxyethyl methacrylate-N-methacryloly-(l)-cysteine methyl ester) cryogel was produced by bulk polymerization. Poly(2-hydroxyethyl methacrylate) was selected as the basic matrix by considering properties, high chemical and mechanical stability. After removal of template (silver ions), the ion-imprinted cryogel was used for the removal of photo-film-containing materials. The dielectric properties of cryogel samples have also been investigated by impedance spectroscopy within the frequency range of 1 Hz-10 MHz. The real part of the permittivity increases at low frequencies as electrode effects become dominant. It shows a constant value at high frequencies due to dipole polarization. On the other hand, the imaginary part does not show a relaxation peak as the relaxation time of samples is very short. The frequency dependence of electrical modulus has also been investigated. The real part of electrical modulus (M ' (f)) is an indicative of negligible electrode polarization phenomenon in the test material. The behavior of the imaginary part of frequency dependent electrical modulus (M '' (f)) exhibit that the dielectric relaxation process is usually not frequency-activated state. Dielectric relaxation process occurs spontaneously due to the hopping mechanism of charge carriers.

Cryogels are an outstanding class of materials with special and functionalized physical properties in various fields and privileges for different industrial applications. Due to unique properties of quantum dots, properties of cryogels can be engineered by adding quantum dots in. In this study, both p(HEMA)-based cryogel and CdSe QDs synthesized and characterized, separately. Then, CdSe QDs were loaded into p(HEMA) cryogels by immersing cryogel into QDs solutions. FTIR-ATR, SEM and TGA characterizations were performed to ensure that CdSe QDs penetrate p(HEMA) cryogels effectively. Dielectric properties of CdSe QDs-loaded cryogel were investigated using Electrical Impedance Spectroscopy (EIS). Real and imaginary parts of dielectric constants were decreased significantly at low frequencies in QD-loaded cryogels. While real part of impedance was increased in CdSe QDs-loaded cryogel at low frequencies. In addition, at high frequencies, those parameters were observed to be same in both cases. Duzce University Scientific Research Project (DUBAP)Duzce University [2017.06.03.592] Authors kindly would like to thank Duzce University Scientific Research Project (DUBAP) Coordination for the support with the project number of 2017.06.03.592. WOS:000562679400007 2-s2.0-85087508329

A dopamine-imprinted monolithic column was prepared and used in capillary electrochromatography as stationary phase for the first time. Dopamine was selectively separated from aqueous solution containing the competitor molecule norepinephrine, which is similar in size and shape to the template molecule. Morphology of the dopamine-imprinted column was observed by scanning electron microscopy. The influence of the organic solvent content of mobile phase, applied pressure and pH of the mobile phase on the recognition of dopamine by the imprinted monolithic column has been evaluated, and the imprinting effect in the dopamine-imprinted monolithic polymer was verified. Developed dopamine-imprinted monolithic column resulted in excellent separation of dopamine from structurally related competitor molecule, norepinephrine. Separation was achieved in a short period of 10 min, with the electrophoretic mobility of 5.81x10(-5)m(2)V(-1)s(-1) at pH 5.0 and 500mbar pressure.