Preparation of smooth siloxane surfaces for AFM visualization of immobilized biomolecules

Development of scanning probe microscopy (SPM) techniques during past decade has made possible to study bioprocesses at a molecular level. Common protocols for immobilization of biomolecules for SPM studies are based on their adsorption to alkylsiloxane monolayers on hydroxylated surfaces. The same procedure is also widely used for DNA chip and biosensor fabrication. For SPM studies of immobilized biomolecules smooth carrier surfaces are mandatory. Several studies refer to the lack of reproducibility in formation of smooth silanized surfaces. In this work a new method based on carrier treatment with linearly polymerized 3-aminopropyltrimethoxysilane for preparation of reproducibly smooth silanized surfaces is proposed.