Department of Engineering and System Science, National Tsing Hua University, No. 101, Sec. 2, Kuang-Fu Rd., Hsinchu 30013, Taiwan, ROC.
Institute of Molecular Medicine, National Tsing Hua University, No. 101, Sec. 2, Kuang-Fu Rd., Hsinchu 30013, Taiwan, ROC.
ACS Appl Mater Interfaces. 2020 Apr 22;12(16):19102-19109. doi: 10.1021/acsami.9b21135. Epub 2020 Apr 8.
Electrodynamic systems for bioanalytical applications constantly suffer from biofouling due to electrical field-induced nonspecific bioadsorption on electrode surfaces. To minimize this issue, surface modification using anti-biofouling and conductive materials is necessary to not only protect the electrode surface from nonspecific bioadsorption but also maintain desired electrodynamic properties for electrode operation. In this study, we designed and prepared a conductive, zwitterionic, and self-doped sulfonated polyaniline (SPANI) coating on Au electrode surfaces for anti-biofouling applications. The zwitterionic coating was fabricated by electrochemical polymerization of aniline on the Au electrode surface functionalized with cysteamine (HS-CHCH-NH) and then a post-polymerization treatment with fuming sulfuric acid. We found that the SPANI-coated electrodes exhibited an excellent anti-biofouling ability in dielectrophoresis (DEP) capturing-and-releasing processes, with a very low average residual mass rate of 1.44% for the SPANI-5s electrode, whereas electrodes modified with poly(ethylene glycol) (PEG) gave an average residual mass rate of 14.30%. Even under continuous operation for more than 1 h, the SPANI-5s electrode still showed stable anti-biofouling ability for an 11-cycle capturing-and-releasing DEP process, with the residual mass rate for all 11 cycles being kept at or below 2.18% to give an average residual mass rate of 1.62% with a standard deviation of 0.40%. This study demonstrates that electrodynamic systems with zwitterionic SPANI coated on open electrode surfaces can excellently function with decent conductance and anti-biofouling performance.
用于生物分析应用的电动系统由于电场诱导的非特异性电极表面吸附而不断受到生物污垢的影响。为了最小化这个问题，需要使用抗生物污垢和导电材料对表面进行修饰，不仅要保护电极表面免受非特异性吸附，还要维持电极操作所需的理想电动特性。在本研究中，我们设计并制备了一种在 Au 电极表面上的导电、两性离子和自掺杂磺化聚苯胺（SPANI）涂层，用于抗生物污垢应用。通过在巯基乙胺（HS-CHCH-NH）功能化的 Au 电极表面上电化学聚合苯胺，并随后用发烟硫酸进行聚合后处理，制备了两性离子涂层。我们发现，SPANI 涂层电极在介电泳（DEP）捕获-释放过程中表现出优异的抗生物污垢能力，SPANI-5s 电极的平均残留质量率非常低，为 1.44%，而用聚乙二醇（PEG）修饰的电极的平均残留质量率为 14.30%。即使在连续运行超过 1 小时后，SPANI-5s 电极在 11 个循环的捕获-释放 DEP 过程中仍表现出稳定的抗生物污垢能力，所有 11 个循环的残留质量率均保持在 2.18%以下，平均残留质量率为 1.62%，标准偏差为 0.40%。这项研究表明，在开放电极表面上涂有两性离子 SPANI 的电动系统可以具有出色的电导和抗生物污垢性能。
