BİOMATBIOMATERIALS AND TISSUE ENGINEERING RESEARCH LABORATORY


Dr. Eda Ayşe Aksoy

 

 

Title: Research Associate
Education: Ph-D. Polymer Science and Techology, METU, 2008
M.Sc. Chem. Dept . METU, 2001 
B.Sc. Chem. Dept. Hacettepe University, 1998
Contact:

Telephone: +90 312 210 6440      
e-mail: edaayse@hacettepe.edu.tr

          edaayseaksoy@gmail.com

 

 

Research Field:

 

Ph.D Thesis: Synthesis and Surface Modification Studies of Biomedical Polyurethanes to Improve Long Term Biocompatibility


In this study, polyurethane (PU) films were synthesized in medical purity from diisocyanate and polyol without using any other ingredients and the chemical, thermal and mechanical properties were characterized by solid state NMR, FTIR, GPC, mechanical tests, DMA and TGA. The surfaces of PU films were modified by covalent immobilization of different molecular weight heparins; low molecular weight heparin (LMWH) and unfractionated heparin (UFH) and these surfaces were examined by ESCA, ATR-FTIR, AFM and contact angle goniometer. Cell adhesion studies were conducted with whole human blood and examined by SEM. The effects of different types of heparins on blood protein adsorption and on platelet adhesion were analyzed by electrophoresis and SEM. The surfaces of the UFH immobilized polyurethane films (PU-UFH) resulted in lesser red blood cell adhesion in comparison to LMWH immobilized polyurethane film surfaces (PU-LMWH). When the PU films were treated with blood plasma, the surfaces modified with two different heparin types showed a clearly different protein adsorption behavior especially in the early stage of blood plasma interaction. PU-LMWH samples showed about three times less protein adsorption compared to PU-UFH samples. The morphologies of platelets adhered on material surfaces demonstrated differences; such as PU-UFH hadclusters with some pseudopodia extensions, while PU-LMWH had round shaped platelets with little clustering. PU surfaces modified by immobilization of LMWH and UFH, demonstrated promising results for the improvement of non-thrombogenic devices and surfaces. This research was granted by METU-BAP2005-07-02-00-92 project and FP6 European Network of Excellence project EXPERTISSUES.


Other Research Activities:


 

  • Preparation and characterization of nano sized antibacterial zeolite - polyurethane composite materials.
  • Self assembly of antibacterial zeolites on polyurethane surfaces.
  • Development of new non-thrombogenic surfaces.

 

 

 

Selected Publications:


  • Aksoy, E.A., Akata, B., Bac, N., Hasirci, N. 'Preparation and Characterization of Zeolite Beta-Polyurethane Composite Membranes', Journal of Applied Polymer Science, 104: 3378-3387, 2007.
  • Hasirci, N., Aksoy, E.A. 'Synthesis and Modifications of Polyurethanes for Biomedical Purposes',High Performance Polymers, 19; 621-637, 2007.
  • Kamışoğlu, K., Aksoy, E.A., Akata, B., Hasirci, N., Bac, N. 'Preparation and Characterization of Antibacterial Zeolite - Polyurethane Composites', Journal of Applied Polymer Science, 110; 2854-2861, 2008.
  • Aksoy, E.A., Hasirci, V., Hasirci, N. 'Surface Modification of Polyurethanes with Covalent Immobilization of Heparin', Macromolecular Symposia, 269; 145-153, 2008.
  • Aksoy, E.A., Kamışoğlu, K., Akata, B., Baç, N., Hasırcı, N. 'Biocompatible Polyurethane Films Incorporation with Antibacterial Silver Loaded Zeolites', Tissue Enginnering-Part A, 14, 5, 813, May 2008.
  • Aksoy, E.A., Motta, A., Fedel, M., Migliaresi, C., Hasirci,V., Hasirci, N. 'Plasma Protein Adsorption and Platelet Adhesion on Heparin-Immobilized Polyurethane Films', Journal of Bioactive and Compatible Polymers, 23, 505-519, 2008.
  • Aksoy, E.A., Hasirci, V., Hasirci, N. 'Synthesis and Structure-Property Behavior of Biomedical Polyurethanes', (under preparation).
 

Patent Application: 

 

  • Processes for Preparation of Medical Grade Polyurethane Composites Containing Antibacterial Zeolite' Turkish Patent Institute .

 

Awards

 

  • Ph-D Thesis Award : 


METU Prof. Dr. Mustafa Parlar Foundation Thesis Award, 19 December 2008, METU, Ankara.


  • Best Poster Award: 


1st National Polymer Science and Tecnology Congress and Exhibition, 21 - 23 June 2006, METU, Ankara.