Probing local water contents of in vitro protein films by ultrasonic force microscopy -: art. no. 123901

By means of ultrasonic force microscopy and lateral force microscopy we measure adhesion hysteresis and friction on protein films of bovine serum albumin and concanavalin A at local scales. Our investigations at different relative humidities (less than 5% and at 50% relative humidity) correspond to dehydrated and hydrated states of proteins. We demonstrate that a substantial increase of adhesion hysteresis with relative humidity is sensitive measure of protein-water binding capacity at local scales. (C) 2005 American Institute of Physics.