The bending of the cantilever due to ad- sorption and molecular interactions between the SAM and complementary molecules (fig. 2A) in solution is in the range of only a few nanometres. This was shown for the first time in DNA hybridisation experiments [9, 10], where the binding of a 12 base long oligonucleotide at a concentration of 80 nM to its complement immobilised on the cantilever surface was studied with single base-pair specificity