Chemical Engineering / Kimya Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/14

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Author: search.filters.author.Alsoy Altınkaya, SacidePublisher: search.filters.publisher.Springer Verlag

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Now showing 1 - 5 of 5
  • Article
    Citation - WoS: 44
    Citation - Scopus: 44
    Chitosan-Polyoxometalate Nanocomposites: Synthesis, Characterization and Application as Antimicrobial Agents
    (Springer Verlag, 2014) Fiorani, Giulia; Saoncella, Omar; Alsoy Altınkaya, Sacide; Alsoy Altınkaya, Sacide; Figoli, Alberto; Bonchio, Marcella; Carraro, Mauro; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Polyoxometalates (POMs) were used, together with chitosan (CS), to obtain hybrid nanoaggregates. Three representative POMs were efficiently assembled into nanoparticles of few hundred nm diameter, featuring entangled ribbons substructure. In order to establish suitable preparation and stability conditions, the assemblies were characterized in solution by UV-Vis spectroscopy, dynamic light scattering and ζ-potential. The nanoparticles were tested against E. coli (106 CFU/ml) in aqueous solution, showing a synergic activity of the heteropolyacid H5PMo10V2O40 and CS. For such components, a highly porous and antibacterial film was obtained upon lyophilisation of the colloidal mixture.
  • Article
    Citation - WoS: 29
    Citation - Scopus: 33
    Surface Modification of Polysulfone Based Hemodialysis Membranes With Layer by Layer Self Assembly of Polyethyleneimine/Alginate-heparin: a Simple Polyelectrolyte Blend Approach for Heparin Immobilization
    (Springer Verlag, 2013) Yaşar Mahlıçlı, Filiz; Alsoy Altınkaya, Sacide; Alsoy Altınkaya, Sacide; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    This study intends to improve blood compatibility of polysulfone (PSF) membranes by generating a nonthrombogenic surface through heparin immobilization. To achieve this task, the support membrane prepared from a blend of PSF and sulfonated polysulfone (SPSF) was modified with layer by layer (LBL) deposition of polyethyleneimine (PEI) and alginate (ALG) and heparin blended with ALG was immobilized only on the outermost surface of the LBL assembly. The results have shown that the adsorption of human plasma proteins and platelet activation on the LBL modified membranes decreased significantly compared with the unmodified PSF and PSF-SPSF blend membranes. Furthermore, blending ALG with a small amount of heparin remarkably prolonged the APTT values of heparin free PEI/ALG coated membranes. It is envisaged that the use of a blend of HEP and ALG only in the terminating layer of the LBL assembly can be an economical and alternative modification technique to create nonthrombogenic surfaces.
  • Article
    Citation - WoS: 9
    Citation - Scopus: 11
    Modeling of Hemodialysis Operation
    (Springer Verlag, 2010) Abacı, Hasan Erbil; Alsoy Altınkaya, Sacide; Alsoy Altınkaya, Sacide; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    In this study, a theoretical model was developed to predict the solute concentrations in patients' blood and optimize the efficiency of the hemodialysis operation. The model takes into account simultaneous mass and momentum transfer on the blood side both in radial and axial directions. A key component of the model is the incorporation of the protein adsorption on the inner surface of the membrane. The validity of the model was confirmed with the experimental data available in the literature for two different types of hemodiafilter. To illustrate the importance of including the radial concentration gradients and protein adsorption kinetics in the model, the experimental data were predicted with and without consideration of these effects. The results have shown that assuming uniform concentration in the radial direction or neglecting protein adsorption on the inner surface of the membrane leads to higher error in predicting the experimental data. In addition, significant error can be introduced in the calculation of the dialysis time if protein adsorption is not considered. © 2010 Biomedical Engineering Society.
  • Article
    Citation - WoS: 11
    Citation - Scopus: 13
    Sorption and Diffusion of Water Vapour on Edible Films
    (Springer Verlag, 2008) Berkün, Didem; Balköse, Devrim; Berkün, Didem; Alsoy Altınkaya, Sacide; Tıhmınlıoğlu, Funda; Balköse, Devrim; Alsoy Altınkaya, Sacide; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Two types of films consisting of sodium salt of carboxymethyl cellulose (NaCMC) and hydroxypropyl cellulose (HPC) as film forming materials and glycerin as plasticizer were prepared, characterized and their water vapour sorption properties were determined. The water sorption isotherms of the films were measured using a magnetic suspension balance. Results show that diffusion of water vapour in NaCMC based film is faster than that in HPC based films, due to the heterogeneous structure and larger pore dimensions of the NaCMC films.
  • Article
    Citation - WoS: 8
    Citation - Scopus: 8
    The Effects of Urease Immobilization on the Transport Characteristics and Protein Adsorption Capacity of Cellulose Acetate Based Hemodialysis Membranes
    (Springer Verlag, 2009) Yaşar Mahlıçlı, Filiz; Alsoy Altınkaya, Sacide; Alsoy Altınkaya, Sacide; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    In this study, cellulose acetate (CA) based hemodialysis membranes were prepared by a dry phase inversion method and the influences of urease immobilization on the clearing performance and protein adsorption capacity of the membranes were investigated. Permeation experiments have shown that modification of CA membranes with urease immobilization not only enhanced the transport rate of urea but also increased the permeation coefficients of uric acid and creatinine by changing the structure of the membrane. Furthermore, the protein adsorption capacity of the CA membranes decreased. On the other hand, the mechanical strength of the modified CA membrane did not change significantly compared with that of the unmodified one. A mathematical model was derived to determine the rate of mass transfer of urea through modified CA membranes. Model predictions along with the experimental data suggest that urease immobilization can be used as an alternative method in preparing CA based hemodialysis membranes with improved transport characteristics and biocompatibility through reduced protein adsorption capacities.