Papers by Author: Udo Bakowsky

Abstract: The preparation and charactersiation of novel gene vehicles based on synthetic organic silicon derivatives are which are formulated as solid lipid nanoparticles (SLN) and liposomes are investigated in the presented study. Physicochemical parameters and morphology were studied by photon correlation spectroscopy, zeta potential measurements (NanoZ Malvern) and Atomic Force Microscopy (Digital Nanoscope IV Bioscope), while the biological activity was determined using a standard in vitro transfection assay and corelated with established gene transfection systems.

Abstract: Protein adhesion on biomaterial surfaces plays a major role in determining their biocompatibility and cell responses. The goal of this study was to produce chitosan-based coatings of implant material polyurethane (PUR) for reduced human serum albumin (HSA) adhesion. Succinic anhydride was employed for modifying chitosan and synthesis of N-succinyl-chitosan (NSCS) which was used as a matrix coating of PUR. NSCS showed self-assembly behaviour as nanofiber structures onto PUR surface. Atomic force microscopy (AFM) has emerged as useful tool for the molecular force measurements and therefore it has been chosen to investigate the adhesion properties of Human serum albumin (HSA) on the new matrix coatings and other three implant materials PUR, Silicon and Titanium. HSA molecules were covalently bound to the AFM tip by the use of cyanuric chloride as bivalent linker. Analyzing the force curves demonstrated the antiadhesive properties of the NSCS films in comparison with the uncoated PUR, Silicon and Titanium.

Abstract: The preparation and charactersiation of novel lipid coated PLGA nanoparticles was investigated in the presented study. The size of the pure nanoparticles could be adjusted in dependence on the stabilizer content. The supported lipid bilayer surrounding the nanoparticles was formed by the liposome spreading technique. The Lipid- coated nanoparticles were characterised using Photon Correlation Spectroscopy (PCS) and atomic force microscopy (AFM) investigations. The bioadhesive properties was proofed in a cell culture model.

Abstract: We report the surface modification of a cellulose dialysis membrane by tetraether lipids and silver colloids to improve the antiadhesive and antibacterial properties of the biopolymer. The lipid was covalently attached to the membrane via the bivalent linker cyanuric chloride. The biologically evaluation show that the adhesion of serum components as well as bacteria, was decreased by this novel coating.