Poly(2-vinylpyridine) is known to be hydrophobic, and a membrane prepared from it would not permeate water-soluble substances in aqueous media. By introducing hydrophilic poly(2-vinyl-N-methylpyridinium iodide) particles into the membrane, it would be possible to control permeation. This type of membrane was prepared and an increase in permeability was observed on increasing the amount of hydrophilic component in the membrane and decreasing the crosslink density of the hydrogel part. The size of the hydrogel particles did not have a significant effect on permeability. Scanning electron microscopy and microscopic examinations showed a homogeneous distribution of hydrogel particles in the membrane matrix.


ARICA, MY; Hasırcı, Vasıf Nejat (1993-01-01)
Poly(2-hydroxyethyl methacrylate) membranes were prepared in aqueous media with different ions and ionic strengths. The enzyme glucose oxidase was incorporated into some of these membranes. It was found that membrane water contents and ionic strengths have a linear relationship as long as the salt is not changed. When the salt was varied, only a relationship between salt concentration and water content could be observed. The membrane permeabilities were all found to be of the same order (10(-8) cm2 s-1) but...
Temperature dependence of the phospholipids bilayers stability, studied by FTIR spectroscopy
Severcan, Feride; Agheorghiesei, Catalin; Dorohoi, Dana-Ortansa (2008-03-01)
The temperature induced modifications in the lipid bilayers in water were studied by using 2D-FTIR Correlation Spectroscopy. The spectral range analysed in this paper corresponds to symmetric and asymmetric stretching vibrations of the -CH2 groups from the acyl chains of DPPC. Autocorrelation peaks at 2916 cm(-1) and 2848.5 cm(-1) and asynchrone modifications in the spectral ranges 2916-3000 cm(-1) and 2848-3000 cm(-1) were evidenced. The revealed modifications indicate changes in the conformers of the hydr...
Peroxidation of membrane lipids in minimally processed cucumbers packaged under modified atmospheres
Karakaş, Barçın; Yıldız, Fatih; Department of Food Engineering (2002)
Peroxidation of membrane lipids is an inherent feature of ripening and senescence of plant tissues. Increased lipid peroxidation has also been observed in the development of chilling injury in susceptible tissues. In this study, the effect of storage conditions and physical tissue damage on membrane peroxidation of minimally processed cucumber (Cucumis sativus, L.) was investigated. Model modified atmospheres were achieved passively by storage of the minimally processed cucumbers at 4°C and 20°C in hermetic...
Viscosity measurement and modeling of lipid supercritical carbon dioxide mixtures
Yener, Meryem Esra; Rizvi, SSH; Harriott, P (1998-01-31)
The viscosities of supercritical carbon dioxide (SC-CO2) containing different levels of methyl oleate and oleic acid were measured with a high pressure capillary viscometer. The SC-CO2-methyl oleate system was evaluated at 313.15, 323.15 and 333.15 K and 11.5, 13.7 and 15.5 MPa, respectively. The SC-CO2-oleic acid system was evaluated at 313.15 K and 20.5 and 30.0 MPa and 333.15 K and 30.0 MPa. The increase in SC-CO2 viscosity was as high as 15-20% at the maximum methyl oleate concentrations (4-5 wt%) and 6...
Covalent immobilization of invertase on chemically activated poly (styrene-2-hydroxyethyl methacrylate) microbeads
A carrier for invertase enzyme was synthesized from styrene (S) and 2- hydroxyethyl methacrylate (HEMA) in the form of microbeads. These poly (styrene-2-hydroxyethyl methacrylate), P(S-HEMA) microbeads were activated by epichlorohydrin (ECH) treatment for covalent immobilization. The free and immobilized invertase were assayed in the hydrolysis of sucrose to glucose, and the obtained results were compared. The optimum pH was 4.5 for free and 5.5 for immobilized invertase. The optimum temperature of invertas...
Citation Formats
H. AKIN, V. N. Hasırcı, and N. Hasırcı, “PERMEABILITY PROPERTIES OF CHARGED HYDROGEL-CARRYING MEMBRANES,” POLYMER, pp. 270–275, 1990, Accessed: 00, 2020. [Online]. Available: