Development and Characterization of Novel Antibacterial, Antiadhesive Films Containing Chitosan-Silver Nanoparticle Complexes and Modified Tetraetherlipids

Eyas Dayyoub, Johannes Sitterberg, Nico Harbach, and Udo Bakowsky

Department of Pharmaceutical Technology and Biopharmaceutics, University of Marburg, Ketzerbach 63, 35037 Marburg, Germany




Biofilm formation is one of the most well-known problems of the urethral catheters, leading to serious infections.
Bacteria within the biofilm have an increased resistance to systemic administrated antibiotics when compared to their free-floating counterparts. A technique that can both reduce the attachment of bacteria onto device surfaces and increase the effectiveness of killing the bacteria on the device surfaces is of prime importance.
Catheter surface modification with films of both anti-adhesive and antibacterial substances is a potential method to avoid bacterial adhesion onto the surface and to raise the antibacterial activity.
This project focuses on the development and characterization of ultrathin antibacterial and anti-adhesive films containing silver nanoparticles, Chitosan and modified Tetraetherlipid (TEL) complexs. The Tetraetherlipids show high chemical stablility in urethral environment and are resistant to hydrolytic, oxidative and other (bio)chemical attack. The TEL were covalently attached to the catheter surface. In addition to this, the well-known antibacterial combination of Chitosan-Silver nanoparticles was used for further modification. This combination shows very high antibacterial activity due to the natural antibacterial properties of Chitosan and due to the wide antimicrobial range of silver nanoparticles.
The physicochemical and biological properties of the supported films were examined by scanning force microscopy (AFM) and confocal laser scanning microscopy(CLSM) regarding their morphology, surface energy, blood serum and bacterial adhesion.