Chemical modification on top of nanotopography to enhance surface properties of PDMS

In the present study we report the surface modification of polydimethylsiloxane (PDMS) via combining both physical and chemical modification routes. Well defined nanostructures were created on PDMS surface through anodized aluminum oxide (AAO) template method. On top of the nanostructures, polyvinyl alcohol (PVA) was coated after the nano patterned PDMS was exposed to air plasma. The influence of the combined modification on surface properties of PDMS was examined by ATR-FTIR and water contact angle measurement. The impact of plasma pretreatment time and storage time in ambient environment were investigated, and property of films with or without nanostructures was compared. Experimental results show that long-term stable hydrophilic surfaces of PDMS can be achieved by PVA coating and be further improved by the surface nanostructures. The modified PDMS was also used for cell culture. The results indicate that both nanostructuring and chemically modifying the PDMS surface improves cell growth. Additionally, combination of these surface modifications has an additive effect on cell proliferation.