Photonic porous silicon as a pH sensor

Stephanie Pace; Roshan B Vasani; Wei Zhao; Sébastien Perrier; Nicolas H Voelcker

doi:10.1186/1556-276X-9-420

Photonic porous silicon as a pH sensor

Nanoscale Res Lett. 2014 Aug 21;9(1):420. doi: 10.1186/1556-276X-9-420. eCollection 2014.

Authors

Stephanie Pace¹, Roshan B Vasani¹, Wei Zhao², Sébastien Perrier³, Nicolas H Voelcker¹

Affiliations

¹ Mawson Institute, University of South Australia, GPO Box 247, Adelaide, South Australia 5001, Australia.
² Key Centre for Polymer Colloids Room 351, School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia.
³ Key Centre for Polymer Colloids Room 351, School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia ; Department of Chemistry, The University of Warwick, Coventry CV4 7AL, UK.

Abstract

Chronic wounds do not heal within 3 months, and during the lengthy healing process, the wound is invariably exposed to bacteria, which can colonize the wound bed and form biofilms. This alters the wound metabolism and brings about a change of pH. In this work, porous silicon photonic films were coated with the pH-responsive polymer poly(2-diethylaminoethyl acrylate). We demonstrated that the pH-responsive polymer deposited on the surface of the photonic film acts as a barrier to prevent water from penetrating inside the porous matrix at neutral pH. Moreover, the device demonstrated optical pH sensing capability visible by the unaided eye.

Keywords: Color change sensor; Porous silicon; RAFT polymerization; pH-responsive polymer.