CNT aerogel film based novel approach for development of ultra-sensitive electrochemical sensor platforms with glassy carbon, screen-printed, and interdigitated electrodes

In sensor applications, the introduction of CNTs onto sensing substrates currently entails intricate processes with concerns over stability. This study introduces a novel approach employing a cast and pull-back technique along with drop-casting for successful binder less deposition of CNTs onto sensing substrates, utilizing a CNT aerogel film to augment the sensitivity of conventional glassy carbon electrodes (GCEs), screen-printed electrodes (SPEs), and interdigitated electrodes (IDEs). Scanning electron microscopy validates the deposition of CNT forests on GCE, entangled CNT networks on SPE, and IDE. Comparative electrochemical analyses reveal impressive performance improvement of SPE and GCE sensors after CNT incorporation. Notably, CNT-incorporated SPE and GCE sensors demonstrate a respective approximately 12- and twofold increase in electrochemical active surface area. For IDE, a significant 1700-fold change in resistance of IDE-CNT in the presence of a redox solution surpasses the 200-fold change observed in bare IDE, underscoring a substantial sensitivity enhancement facilitated by CNT incorporation. The mechanical integrity of CNT aerogel film post-exposure to liquids and sonication attests to its robust nature. The preservation of the deposited CNT forest on the SPE and GCE sensor platforms after multiple measurements further underscores its stability. This study showed that the CNT aerogel film is well-suited for the transfer of CNT networks in a simple way onto diverse sensing substrates, thereby showcasing its potential to advance biomedical sensor technology.