Aminosilane patterning on substrate surface by PDMS soft stamp for proteoglycan molecular immobilization

Abstract

This paper presents amino-terminated micro pattern transferring onto a mica substrate using polydimethylsiloxane (PDMS) soft stamp and proteoglycan (PG) molecular immobilization. PDMS bump-arrays with ultra-smooth surface were fabricated utilizing anisotropic etched silicon substrate as a mold. Coating and removal of releasing-agents were investigated to improve detachability of PDMS stamp from silicon substrate. Residual releasing-agents on the surface of the PDMS stamp were completely removed by repeated stamping on dummy mica substrates. After the PDMS stamp was immersed into aminopropyltriethoxysilane (APTES) solution, followed by drying with nitrogen gas blowing, APTES molecules on the PDMS stamp were transferred onto mica substrate. After PG solution was deposited onto the APTES transferred mica substrate, the PG molecules were immobilized both inside and outside the APTES transferred pattern. PG molecules with widely spread glycosaminoglycan (GAG) molecules were successfully immobilized inside the APTES pattern due to amino-termination effect whereas PG molecules with no GAG spreading were also adsorbed outside the pattern.