Skorupska, K.; Lewerenz, H.J.; Vo-Dinh, T.: Scanning probe characterization of enzymes deposited onto step-bunched silicon nanostructures. Physica Scripta 79 (2009), p. 065801/1-4
10.1088/0031-8949/79/06/065801
Abstract:
Step-bunched Si surfaces with step heights of ~ 3 nm have been prepared as substrates for immobilization of the enzyme reverse transcriptase of the avian myeloblastosis virus. Tapping mode atomic force microscopy has been used for imaging. Calibration experiments using the carrier solution without the enzyme show the preservation of the surface without organic contamination. Upon enzyme deposition, two specific shapes of the enzymes are observed to be adsorbed on the surface after rinsing with ultrapure water. Data analysis reveals that adsorption takes place at kink and reentrant sites on the surface and along step edges but not on the planar parts of the base (111) surface. The adsorption is interpreted by a combination of electrostatic and van der Waals interaction in accordance with the framework of the DLVO4 theory.