Scanning tunneling microscopy for studying the biomaterial–biological tissue interface

Abstract

A scanning tunneling microscope (STM) coupled with a high resolution reflective optical microscope has been developed to investigate some aspects of the interface between metallic biomedical implants and living tissue. Initial biological measurements show that fibronectin (Fn), a glycoprotein which plays an important role in the promotion of cell and bacterial attachment, is well adsorbed on Ti and V substrates, but is not biologically active on V. STM images of the Ti oxide layer and of single and multiple Fn molecules deposited on mica and shadowed with a conductive layer are presented. These images demonstrate the capability of the STM for studying clinical implant surfaces with roughness larger than 1 μm as well as interface biochemical processes at the molecular level.