Enhancement of antibacterial properties of polyurethanes by chitosan and heparin immobilization

Kara, Filiz
Hasırcı, Nesrin
Being antibacterial is a required property for the materials used in medical devices and instruments. Polyurethanes (PUs) are one class of polymers widely used in the production of devices that especially come in contact with blood (e.g. heart valves, blood vessels, vascular grafts and catheters). In this study, hexamethylene diisocyanate based polyurethanes (PUh) were synthesized and antibacterial and anti-adhesive properties were added by immobilizing chitosan (CH) and heparin (Hep) on the samples of PUh via a stepwise process. Chemistry and topography of the modified film samples (PUh-CH and PUh-CH-Hep) were examined by Fourier Transform Infrared Spectrophotometry-Attenuated Total Reflectance (FTIR-ATR), Electron Spectroscopy for Chemical Analysis (ESCA) and Atomic Force Microscopy (AFM), and surface free energy (SFE) values after each step were determined by goniometer. PUh-CH and PUh-CH-Hep samples were found to be antibacterial against Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis) (both Gram positive) and Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa)( both Gram negative) bacteria, and bacterial adhesion results showed a significant decrease in the number of viable bacteria on both modified samples where PUh-CH-Hep was the most effective. The findings of this study show that polymeric surfaces can be effectively modified and converted to be antibacterial by chitosan and heparin immobilization, and presence of both chemicals enhance efficacy against bacteria.


Synthesis and surface modification of polyurethanes with chitosan for antibacterial properties
Kara, Filiz; AKSOY, EDA AYŞE; YÜKSEKDAĞ, ZEHRANUR; Hasırcı, Nesrin; AKSOY, SERPİL (2014-11-04)
Surface modification and providing antibacterial properties to the materials or devices are getting great attention especially in the last decades. In this study, polyurethane (PU) films were prepared by synthesizing them in medical purity from toluene diisocyanate and polypropylene ethylene glycol without using any other ingredients and then the film surfaces were modified by covalent immobilization of chitosan (CH) which has antibacterial activity. CH immobilized PU films (PU-CH) were found to be more hyd...
Özkaragöz, Nadire Nazlı; Dericioğlu, Arcan Fehmi; Department of Metallurgical and Materials Engineering (2022-2-08)
Ferroelectric materials are used in different applications because of their superior electrical and dielectric properties. Ferroelectric materials are polarized when an electrical field is applied to the material. This spontaneous polarization continues even if an electrical field is removed. BST (Barium Strontium Titanate) is one of the attractive ferroelectric materials which has a high dielectric constant and low dielectric loss tangent (tanδ). High dielectric constant and low loss tangent are necessary ...
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Several polymers derived from natural materials are effective for tissue engineering or drug delivery applications, due to specific properties, such as biocompatibility, biodegradability, and structural activity. Their blood compatibility needs to be carefully evaluated to avoid thrombosis and other material-related adverse events in the hematic environment. We compared the surface properties and blood compatibility of protein and polysaccharide polymers, including fibroin, gelatin, and chitosan. Both fibro...
Modeling of Spherulite Microstructures in Semicrystalline Polymers
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Polymers constitute an important class of materials with a wide range of application areas in modern life. Among these, semicrystalline polymers (SCP), such as high-density polyethylene (HDPE), Nylon-6, poly(ethylene terephthalate) (PET), isotactic polypropylene (iPP) and ultra high molecular weight polyethylene (UHMWPE), form a sub-set with a significant technological interest. Owing to remarkable deformability and toughness, good impact strength, very low gas-permeability, superior wear resistance and bio...
Novel Fluorescent Azacyanine Compounds: Improved Synthesis and Optical Properties
Doğan, Kübra; Forough, M; Persil Çetinkol, Özgül (2020-09-01)
Benzothiazoles are known to possess a number of biological activities and therefore are considered to be an important scaffold in the design and synthesis of pharmacophores. In this study, an improved synthesis method for novel fluorescent benzothiazole-based cyclic azacyanine (CAC) dyes bearing different electron-donating/withdrawing groups on their scaffold is presented. The improved method enabled us to increase the synthesis yield for the previously reported CACs. More importantly, it allowed us to synt...
Citation Formats
F. Kara, E. AKSOY ALP, Z. YÜKSEKDAĞ, S. AKSOY, and N. Hasırcı, “Enhancement of antibacterial properties of polyurethanes by chitosan and heparin immobilization,” APPLIED SURFACE SCIENCE, pp. 1692–1702, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31079.