Instituto de Telecomunicações and Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, P-1049-001 Lisboa, Portugal.
Instituto de Telecomunicaçõ es, i4HB-Institute for Health and Bioeconomy and iBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, P-1049-001 Lisboa, Portugal.
Bioelectrochemistry. 2022 Jun;145:108099. doi: 10.1016/j.bioelechem.2022.108099. Epub 2022 Mar 17.
The potential of the electrical double layer (EDL) formed at the interface between cross-linked poly (3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate) (PEDOT:PSS) and phosphate-buffered saline (PBS) was measured with respect to a reference Ag/AgCl electrode, yielding a value of ca. 300 mV, which corresponds to a work function of 4.9 eV. More importantly, we report that the application of a voltage along the PEDOT:PSS substrate induces a modification of the EDL, which mirrors the potential applied to the PEDOT:PSS underneath. This is translated into an ionic electric field, tangential to the interface that images the electric field applied to the PEDOT:PSS. We propose that this modification of the EDL, via application of the electrical field away from the cell culture medium, is at origin of the neural stem cell response to that field, when cultured on top of PEDOT:PSS. Despite the comparatively low value of the Debye length (estimated around 1 nm) with respect to the much larger cell to PEDOT:PSS surface distance, we believe that the perturbation of the EDL is the likely source of the increase of neuronal differentiation of the neural stem cells. We discuss other possible implications of that EDL modulation.
在交联聚（3,4-亚乙基二氧噻吩）掺杂聚（苯乙烯磺酸盐）（PEDOT:PSS）与磷酸盐缓冲盐水（PBS）之间的界面处形成的双电层（EDL）的电位相对于参比 Ag/AgCl 电极进行了测量，得到约 300 mV 的值，这对应于 4.9 eV 的功函数。更重要的是，我们报告说，沿 PEDOT:PSS 衬底施加电压会引起 EDL 的修饰，这反映了施加到 PEDOT:PSS 下面的电位。这转化为与界面相切的离子电场，该电场反映了施加到 PEDOT:PSS 的电场。我们提出，通过在远离细胞培养基的地方施加电场来修饰 EDL，是培养在 PEDOT:PSS 上的神经干细胞对该电场产生反应的原因。尽管相对于更大的细胞与 PEDOT:PSS 表面的距离，德拜长度（估计约为 1 nm）的相对值较低，但我们认为 EDL 的扰动可能是神经干细胞神经元分化增加的原因。我们讨论了 EDL 调制的其他可能影响。
