Selective nanopatterning of protein via ion-induced focusing and its application to metal-enhanced fluorescence.

Selective immobilization onto the designated sites is particularly important as well as maintaining high spatial resolution down to the nanoscale to prevent unwanted nonspecifi c protein interactions. [ 6 , 7 ] Most previous attempts to form protein nanoarrays were done based on dip-pen nanolithography, which has been demonstrated as able to ensure nanoscale resolution with high selectivity. [ 8–13 ] However, dip-pen lithography is inherently a serial process, even though a parallel approach was recently reported. [ 12 ] Previously developed parallel methods for patterning proteins include microcontact printing, [ 14 , 15 ] ink jet printing, [ 16 , 17 ] optical printing, [ 18 ]