Amino acid conjugated self assembly molecules modified SI wafers

Abstract

In this thesis, Si wafer surface was modi ed with newly synthesized selfassembled monolayers to mimic a biocompatible micro-environment for the cells and to observe their behavior. Begin with; Si wafer is chosen as its availability is easy and well-established structures can be obtained in the surface modi cation without any interference. In the rst step, Si wafers were cleaned and modi cation of surfaces was carried out with amino acid conjugated self-assembled molecules [Histidine-Self Assembled Molecule (His-SAM), and Leucine-Self Assembled Molecule (Leu-SAM)], (3-aminopropyl)triethoxysilane (APTES) and also poly-L-ornithine (PLO). The characterization of these samples were analyzed with contact angle measurements, X-Ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM), and ellipsometry. After characterization results were acquired, the cell culture studies were performed with L929 cells. In order to obtain information about cell proliferation, MTT assay (a colorimetric assay) was performed. According to these results, enhanced cell proliferation was achieved by the contribution of surface functional groups. Consequently, it has been observed that these controlled molecular structures on the surfaces of materials have a great potential for biomedical applications.|Keywords : Silicon Wafer, Surface Modi cation, Self-assembled Molecules (SAMs), Amino Acids.