Kerr Emily, Alexander Richard, Francis Paul S, Guijt Rosanne M, Barbante Gregory J, Doeven Egan H
Institute for Frontier Materials, Deakin University, Geelong, VIC, Australia.
Centre for Regional and Rural Futures, Deakin University, Geelong, VIC, Australia.
Front Chem. 2021 Jan 28;8:628483. doi: 10.3389/fchem.2020.628483. eCollection 2020.
We examined a series of commercially available screen-printed electrodes (SPEs) for their suitability for electrochemical and electrogenerated chemiluminescence (ECL) detection systems. Using cyclic voltammetry with both a homogeneous solution-based and a heterogeneous bead-based ECL assay format, the most intense ECL signals were observed from unmodified carbon-based SPEs. Three commercially available varieties were tested, with Zensor outperforming DropSens and Kanichi in terms of sensitivity. The incorporation of nanomaterials in the electrode did not significantly enhance the ECL intensity under the conditions used in this evaluation (such as gold nanoparticles 19%, carbon nanotubes 45%, carbon nanofibers 21%, graphene 48%, and ordered mesoporous carbon 21% compared to the ECL intensity of unmodified Zensor carbon electrode). Platinum and gold SPEs exhibited poor relative ECL intensities (16% and 10%) when compared to carbonaceous materials, due to their high rates of surface oxide formation and inefficient oxidation of tri--propylamine (TPrA). However, the ECL signal at platinum electrodes can be increased ∼3-fold with the addition of a surfactant, which enhanced TPrA oxidation due to increasing the hydrophobicity of the electrode surface. Our results also demonstrate that each SPE should only be used once, as we observed a significant change in ECL intensity over repeated CV scans and SPEs cannot be mechanically polished to refresh the electrode surface.
我们研究了一系列市售的丝网印刷电极（SPE），以评估它们在电化学和电化学发光（ECL）检测系统中的适用性。使用循环伏安法，在基于均相溶液和基于异质珠的ECL检测形式下，未修饰的碳基SPE观察到最强的ECL信号。测试了三种市售品种，其中Zensor在灵敏度方面优于DropSens和Kanichi。在本评估所使用的条件下，将纳米材料掺入电极中并未显著提高ECL强度（例如，与未修饰的Zensor碳电极的ECL强度相比，金纳米颗粒为19%、碳纳米管为45%、碳纳米纤维为21%、石墨烯为48%、有序介孔碳为21%）。与含碳材料相比，铂和金SPE的相对ECL强度较差（分别为16%和10%），这是由于它们的表面氧化物形成速率高以及三丙胺（TPrA）氧化效率低。然而，添加表面活性剂可使铂电极处的ECL信号增加约3倍，这是因为增加了电极表面的疏水性从而增强了TPrA的氧化。我们的结果还表明，每个SPE只能使用一次，因为我们观察到在重复的循环伏安扫描过程中ECL强度发生了显著变化，并且SPE不能通过机械抛光来更新电极表面。
