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Plasma polymerized polyacrylic acid (PPAA) was deposited on a polymer substrate, namely polyethylene terephthalate (PET) mesh, for entrapment of silver nanoparticle (Ag-NP) in order to achieve antibacterial property to the material. Carboxylic groups of PPAA act as anchor as well as capping and stabilizing agents for Ag-NPs synthesized by chemical reduction method using NaBH(4) as a reducing agent. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS), and water contact angle analysis were used to characterize the PPAA coatings. The Ag-NPs loaded polymer samples were characterized by UV-visible spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray, and XPS techniques. XPS analysis showed ~1.0 at.% loading of Ag-NPs on to the PPAA-PET-mesh, which was composed of 79% zero-valent (Ag°) and 21% oxidized nano-Ag (Ag(+) ). The plasma processed PET meshes samples were tested for antibacterial activity against two bacterial strains, namely Staphylococcus aureus (Gram positive) and Escherichia coli (Gram negative). Qualitative and quantitative tests showed that silver containing PPAA-PET meshes exhibit excellent antibacterial property against the tested bacteria with percent reduction of bacterial concentration >99%, compared to the untreated PET mesh., (Copyright © 2012 Wiley Periodicals, Inc.)

In this study, sulphated polysaccharides were investigated in respect to their blood compatibility properties (hemocompatibility). Pure chitosan was treated with sulphating agents such as SO(3)/pyridine complex and chlorosulfonic acid (HClSO(3)) to obtain 3,6-O-sulfochitosan with low and high concentration of sulfur. These synthetically derived materials and the commercially available sulphated polysaccharides heparin and dextran sulfate, both with high concentrations of sulfur, were coated onto PET foils to act as surfaces with strong antithrombotic activity. This treatment should lead to better blood compatibility properties of PET materials for medical applications. To examine this, the optimized free hemoglobin method was applied to determine the antithrombotic activity of these surfaces. Glass as the standard thrombotic surface and a heparin-coated PET surface as a surface well-known for its strong antithrombotic activity were used as internal references. The experiments showed that dextran sulfate and sulphated chitosan with high concentrations of sulfur demonstrated the same antithrombotic activity as heparin over the whole period of measurement time. In addition, a relationship between the sulfur concentration in these sulphated polysaccharides and their blood compatibility properties can be demonstrated in this article.