Conformation of microcontact-printed proteins by atomic force microscopy molecular sizing.

We investigated the structural changes occurring in proteins patterned via microcontact printing. This was done by molecular sizing using atomic force microscopy to observe the structure of printed individual metalloprotein molecules in the unlabeled and untreated states. We observed that the size of the printed proteins were more than 2-fold smaller than the native shape, which indicates that some deformations take place upon the contact-assisted adsorption on silanized silicon dioxide. This can be attributed to simultaneously occurring effects, and particularly to the sandwiching between surfaces of very different hydrophilic/hydrophobic properties during contact lithography.