ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Future Industries Institute, University of South Australia, South Australia, Australia.
Centre for Environmental Risk Assessment and Remediation, University of South Australia, South Australia, Australia; Faculty of Environmental Agricultural Sciences, Suez Canal University, North Sinai, Egypt.
Biomaterials. 2016 Jan;74:217-30. doi: 10.1016/j.biomaterials.2015.09.045.
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.
未来医学中的先进生物传感器依赖于生物材料的发展。多孔硅（pSi）是一种普遍可生物降解和生物相容的材料，可以被制造为具有环境响应光学特性的材料，是体内生物传感器的优秀候选材料。然而，将这种材料用作皮下植入式光学生物传感器的可行性尚未得到证实。在这里，我们研究了热解烃（THC）pSi 光学波纹滤光片的稳定性和生物相容性，并在体外和体内证明了其光学功能。我们首先比较了具有不同表面化学性质的 pSi 薄膜，并观察到尽管 THC pSi 薄膜具有出色的稳定性，但该材料仍具有细胞毒性。然后我们表明，细胞毒性与活性氧水平相关，而 THC pSi 的预孵育（PITHC pSi）可以减轻这种毒性。PITHC pSi 促进正常细胞表型，在体内具有生物相容性。重要的是，该材料还具有光学特性，能够响应微环境变化，并且在细胞培养和皮下环境中可以进行非侵入性的可读检测。总之，我们首次证明，PITHC pSi 波纹滤光片既具有生物相容性，又具有用于芯片实验室和皮下生物传感场景的光学功能。我们相信，这项研究将加深我们对细胞-pSi 相互作用的理解，并促进植入式生物传感器的发展。
