A method for in situ controlling the detachment and deposition of organic
molecules such as sugars and biocompatible polymers in aqueous solutions by
electron-beam (EB) scan is proposed and evaluated. It was demonstrated that EB
irradiation could detach 2-methacryloyloxyethyl phosphorylcholine (MPC) polymers
from a silicon nitride membrane. Moreover, organic molecules such as cationic
polymers and sugars could be deposited on the membrane by EB irradiation.
Spatial distributions of scattered electrons were numerically simulated, and
acceleration voltage dependences of the detachment and deposition phenomena were
experimentally measured. The simulations and experimental results suggest that
the detachment of MPC polymers is mainly due to electrical effects of primary
electrons, and that the deposition of organic molecules is mainly due to
chemical reactions induced by primary electrons. In view of these findings, the
proposed method can be applied to in situ and nanoscale patterning such as the
fabrication of cell scaffolds.