Scanning probe microscopic and optical detection of DNA integration within multicomponent structures on Si surfaces

Abstract

Self-arrangement of DNA based structures on clean mica and modified Si surfaces is investigated by means of scanning probe microscope (SPM) and spectroscopic ellipsometry (SE) method. DNA strands are deposited from a colloidal solution on solid surfaces at room temperature. Surfaces of solid substrates and biomolecular structures are additionally modified by Ag nanoparticles. The self-arranged surface structures are visualized by SPM. The effect of the multicomponent structures on the optical response of complex hybrid structures is studied. Changes in the optical response of the hybrid samples are related to the contributions of self-assembled DNA-based structures and Ag nanoparticles on the Si surfaces. Binding of Ag nanoparticles to the DNA strands and formation of well-ordered structures on the surfaces with DNA are discussed.
Keywords: biomolecular structures, surface, self-assemblage, optical properties, scanning probe microscopy
PACS: 68.37.Ps, 78.68.+m, 81.07.Pr, 81.16.Dn