SURFACE STRESS IN THE SELF-ASSEMBLY OF ALKANETHIOLS ON GOLD

Surface stress changes and kinetics were measured in situ during the s elf-assembly of alkanethiols on gold by means of a micromechanical sen sor. Self-assembly caused compressive surface stress that closely foll owed Langmuir-type adsorption kinetics up to monolayer coverage. The s urface stress at monolayer coverage increased linearly with the length of the alkyl chain of the molecule. These observations were interpret ed in terms of differences in surface potential. This highly sensitive sensor technique has a broad range of applicability to specific chemi cal and biological interactions.