Surface chemistry modification of PDMS elastomers with boiling water improves cellular adhesion

Polydimethylsiloxane (PDMS) lacks cell binding sites and requires additional treatments such as a routine extracellular matrix coating process to culture cells on it. Here we propose a simple method to improve the cytophilicity of hydrosilylation cured PDMS elastomers by using boiling water; placing the crosslinked PDMS substrate in boiling deionized water for about 1 h generates hydroxyl groups on the surface derived from residual SiH functional groups present in the cured elastomers that act as good binding sites for cell attachment. Modified chemistry of the PDMS surface was confirmed by using attenuated total reflection infrared (ATR-IR) analysis. The beneficial biological effects were demonstrated through enhanced attachment/spreading of human mesenchymal stem cells on the boiling-treated surface of PDMS. The results show that boiling water treatment offers a mild, convenient, and cost-effective method to improve the surface cytophilicity of PDMS.