Dynamic force microscopy in liquids

Abstract

We applied dynamic force microscopy in a liquid environment to silanized and derivatized glass surfaces, InGaAs, as well as to biological materials such as hexagonally packed intermediate layers of deinococcus radiodurans. The vertical and lateral resolution were estimated to be <1 Å and 7–10 nm, respectively. Upon immersing the cantilever into water, the resonance frequency was found to be reduced by a factor of two and the Q factor was lowered to 20–30. The experimental working distance between sensor and sample was determined with approach curves indicating that the range of interaction in water is much shorter compared to air.