Layouni Rabeb, Choudhury Moinul H, Laibinis Paul E, Weiss Sharon M
Department of Chemical & Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235 United States.
Department of Electrical Engineering & Computer Science, Vanderbilt University, Nashville, Tennessee 37235 United States.
ACS Appl Bio Mater. 2020 Jan 21;3(1):622-627. doi: 10.1021/acsabm.9b01002. Epub 2019 Dec 20.
In this work, thermal carbonization is shown to provide the necessary surface passivation to enable highly robust DNA detection on a porous silicon (PSi) platform, overcoming previous corrosion challenges with detection of negatively charged biomolecules. The stability of thermally carbonized PSi (TCPSi), oxidized PSi (OPSi), and undecylenic acid-modified PSi (UAPSi) is compared in phosphate-buffered saline and during DNA sensing experiments. Reflectance measurements reveal an improvement in stability and DNA sensor response for TCPSi compared to OPSi and UAPSi. TCPSi exhibits a large positive sensor response with >90% DNA hybridization efficiency. In comparison, UAPSi shows a smaller positive DNA sensor response, likely lessened by a small corrosion effect, while OPSi exhibits a large negative sensor response, indicating significant induced PSi corrosion that confounds the ability of OPSi to yield meaningful readouts of DNA hybridization events. This work expands the application of TCPSi for its more widespread usage in sensing applications where competing substrate corrosion may influence device stability.
在本工作中，热碳化被证明能提供必要的表面钝化，从而在多孔硅（PSi）平台上实现高度稳健的DNA检测，克服了此前在检测带负电荷生物分子时的腐蚀挑战。在磷酸盐缓冲盐溶液中以及DNA传感实验期间，对热碳化PSi（TCPSi）、氧化PSi（OPSi）和十一烯酸修饰PSi（UAPSi）的稳定性进行了比较。反射率测量结果表明，与OPSi和UAPSi相比，TCPSi的稳定性和DNA传感器响应有所改善。TCPSi表现出较大的正向传感器响应，DNA杂交效率>90%。相比之下，UAPSi显示出较小的正向DNA传感器响应，可能是由于轻微的腐蚀效应而减弱，而OPSi则表现出较大的负向传感器响应，表明PSi发生了显著的诱导腐蚀，这混淆了OPSi对DNA杂交事件产生有意义读数的能力。这项工作扩展了TCPSi的应用，使其在传感应用中得到更广泛的使用，在这些应用中，竞争性的基底腐蚀可能会影响器件稳定性。
