Towards a subcutaneous optical biosensor based on thermally hydrocarbonised porous silicon

Wing Yin Tong, Martin J. Sweetman, Ezzat R. Marzouk, Cara Fraser, Tim Kuchel, Nicolas H. Voelcker

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Advanced biosensors in future medicine hinge on the evolvement of biomaterials. Porous silicon (pSi), a generally biodegradable and biocompatible material that can be fabricated to include environment-responsive optical characteristics, is an excellent candidate for in vivo biosensors. However, the feasibility of using this material as a subcutaneously implanted optical biosensor has never been demonstrated. Here, we investigated the stability and biocompatibility of a thermally-hydrocarbonised (THC) pSi optical rugate filter, and demonstrated its optical functionality in vitro and in vivo. We first compared pSi films with different surface chemistries and observed that the material was cytotoxic despite the outstanding stability of the THC pSi films. We then showed that the cytotoxicity correlates with reactive oxygen species levels, which could be mitigated by pre-incubation of THC pSi (PITHC pSi). PITHC pSi facilitates normal cellular phenotypes and is biocompatible in vivo. Importantly, the material also possesses optical properties capable of responding to microenvironmental changes that are readable non-invasively in cell culture and subcutaneous settings. Collectively, we demonstrate, for the first time, that PITHC pSi rugate filters are both biocompatible and optically functional for lab-on-a-chip and subcutaneous biosensing scenarios. We believe that this study will deepen our understanding of cell-pSi interactions and foster the development of implantable biosensors.

Original languageEnglish
Pages (from-to)217-230
Number of pages14
JournalBiomaterials
Volume74
DOIs
Publication statusPublished - 1 Jan 2016

Keywords

  • Biocompatibility
  • Biodegradation
  • Biosensor
  • Cytotoxicity
  • Silicon
  • Subcutaneous implant

ASJC Scopus subject areas

  • Bioengineering
  • Ceramics and Composites
  • Biophysics
  • Biomaterials
  • Mechanics of Materials

Cite this

Tong, W. Y., Sweetman, M. J., Marzouk, E. R., Fraser, C., Kuchel, T., & Voelcker, N. H. (2016). Towards a subcutaneous optical biosensor based on thermally hydrocarbonised porous silicon. Biomaterials, 74, 217-230. https://doi.org/10.1016/j.biomaterials.2015.09.045