A new affinity-HPLC packing for protein separation: Cibacron blue attached uniform porous poly(HEMA-<Emphasis Type="Italic">co</Emphasis>-EDM) beads

In this study, a new affinity high-performance liquid chromatography (HPLC) stationary phase suitable for protein separation was synthesized. In the first stage of the synthesis, uniform porous poly(2-hydroxyethyl methacrylate-co-ethylene dimethacrylate), poly(HEMA-co-EDM), beads 6.2 μm in size were obtained. Homogeneous distribution of hydroxyl groups in the bead interior was confirmed by confocal laser scanning microscopy. The plain poly(HEMA-co-EDM) particles gave very low non-specific protein adsorption with albumin. The selected dye ligand Cibacron blue F3G-A (CB F3G-A) was covalently linked onto the beads via hydroxyl groups. In the batch experiments, albumin adsorption up to 60 mg BSA/g particles was obtained with the CB F3G-A carrying poly(HEMA-co-EDM) beads. The affinity-HPLC of selected proteins (albumin and lysozyme) was investigated in a 25 mm×4.0-mm inner diameter column packed with CB F3G-A carrying beads and both proteins were successfully resolved. By a single injection, 200 μg of protein was loaded and quantitatively eluted from the column. The protein recovery increased with increasing flow rate and salt concentration of the elution buffer and decreased with the increasing protein feed concentration. During the albumin elution, theoretical plate numbers up to 30,000 plates/m were achieved by increasing the salt concentration.     

Fluorescence Interaction and Determination of Sulfathiazole with Trypsin

The mechanism of interaction of trypsin with the sulfathiazole was studied through using fluorescence quenching and UV-visible absorption spectra at pH 7.4. The Stern-Volmer quenching constants, binding constants, number of binding sites and the corresponding thermodynamic parameters ΔH^o, ΔS^o and ΔG^o were calculated at different temperatures. The effect of common metal ions on the constants was also discussed. The results suggest that sulfathiazole can interact strongly trypsin and that there is the formation of trypsin-sulfathiazole complex and the interaction can be explained on the basis of hydrogen bonds and van der Waals forces. The binding distance (r) between the donor (trypsin) and acceptor (sulfathiazole) was 3.52 nm based on the Förster’s non-radiative energy transfer theory. The detection and quantification limits of sulfathiazole were calculated as 2.52 and 8.40 μM in the presence of trypsin, respectively. The relative standard deviation (RSD) was 4.086 % for determinations (n?=?7) of a sulfathiazole solution with the concentration of 7.54 μM.     

Some relations between certain inequalities concerning analytic and univalent functions

By making use of the well-known assertions in [S.S. Miller, P.T. Mocanu, Differential Subordinations, Theory and Applications, Marcel Dekker, New York-Basel, 2000] and [M. Nunokawa, On the order of strongly starlikeness of strongly convex functions, Proc. Japan Acad. Ser. A Math. Sci. 69 (7) (1993) 234–237], several useful results of certain inequalities dealing with analytic and univalent functions are obtained and then certain consequences of them are also indicated.     

Study on the stability of supercritical fluid extracted rosemary (<Emphasis Type="Italic">Rosmarinus offcinalis</Emphasis> L.) essential oil

The aim of this study was to examine the influence of storage conditions and duration on composition and antioxidant activity of supercritical fluid (SCF) extracted essential oil of rosemary (Rosmarinus officinalis L.). Supercritical extraction was carried out sequentially by using SCF carbondioxide in the first two steps and with 5% ethanol as entrainer in the third step. The compositions of the extracts were determined by gas chromatography/mass spectrometry. The total phenolics were analyzed using Folin-Ciocalteau assay. Antioxidant activities of the extracts were tested by β-carotene-linoleic acid bleaching method.     

First synthesis of a carbohydrate-derived pyridyl bis(thiazoline) ligand

The first synthesis of a carbohydrate-based pyridyl bis(thiazoline) ligand starting from d-glucosamine and its application in asymmetric cyclopropanation reactions are reported.     

Utilization of Fly Ash Nanofluids in Two-phase Closed Thermosyphon for Enhancing Heat Transfer

This study investigates how fly ash nanofluids affect the thermal performance of a two-phase closed thermosyphon at various states of operation. The utilization of nanofluids obtained from X₂O₃-type oxides, such as Al₂O₃, Fe₂O₃, or CuO, on the improvement of two-phase closed thermosyphon performance was reported in a number of studies in the literature. The present study experimentally demonstrated the effect of using a nanofluid obtained from fly ash comprised of various types of metal oxides in varying ratios on improving the performance of a two-phase closed thermosyphon. The fly ash was obtained from the flue gas that was captured in the cyclones of the Yatagan thermal power plant (Turkey). Triton X-100 (Dow Chemical Company) dispersant was used in the study to produce the 0.2% (wt) fly ash/water nanofluid via direct synthesis. A straight copper tube with an inner diameter of 13 mm, outer diameter of 15 mm, and length of 1 m was used as the two-phase closed thermosyphon. The nanofluid filled 33.3% (44.2 ml) of the volume ofthe two-phase closed thermosyphon. Three heating power levels (200, 300, and 400 W) were used in the experiments with three different flow rates of cooling water (5, 7.5, and 10 g/s) used in the condenser for cooling the system. A increase of 26.39% was achieved in the efficiency of the two-phase closed thermosyphon when 4% (wt) fly ash containing nanofluid was used to replace deionized water at a heat load of 200 W and with a cooling water flow rate of 5 g/s.     

glucoBox--a new carbohydrate-based bis(oxazoline) ligand. Synthesis and first application

The synthesis of a new bis(oxazoline) ligand from D-glucosamine and its application in enantioselective copper(I) catalysed cyclopropanations of olefins is described.     

Deposition of MgF2 thin films for antireflection coating by using thermionic vacuum arc (TVA)

In this study, optical and surface properties of MgF₂ thin films produced by thermionic vacuum arc (TVA) technique have been investigated. By means of this technique the MgF₂ thin film produced by condensing the plasma of anode material generated by using TVA under high vacuum conditions on the glass. The optical properties have been investigated by using Filmetrics F20 and UV/VIS spectrometer. For surface properties of produced thin films EDS, SEM and AFM have been used. Our analysis shows that MgF₂ thin films produced by using TVA are proper single and multi layer anti-reflective (AR) coating and TVA technique brings very important advantages for ophthalmic glass coating and industrial applications' optical purposes.