Effect of Micro‐ and Nanomorphology of Carbon Nanotube Electrochemical Electrodes on Virus Sensing

Carbon nanotube (CNT) films are expected to be applied to electrochemical electrodes owing to their physical and chemical robustness and large specific surface area derived from their network structure. However, because of their complex structural factors, such as chirality, dispersion, bundling, and film density, the optimal CNT structure that can be used for electrochemical electrodes has not been determined yet. Moreover, a virus‐sensing technology that can be easily used outside of specialized locations is required. This study addresses these issues by first describing the effect of the micro‐ and nanomorphology of CNT electrochemical electrodes on virus sensing. Subsequently, a comparison of antigen–antibody reactions for CNT electrochemical electrodes fabricated using different synthesis methods, dispersants, and surface roughness is performed. Results indicate that CNTs with high conductivity and antibody modification have the optimal structure for use in electrochemical electrodes. Moreover, highly sensitive norovirus sensing with a limit of detection of 1 fg mL ⁻¹ is accomplished. A relationship between the CNT structure and electrochemical reactions is unprecedentedly elucidated. Thus, this study can serve as a guideline for developing high‐performance electrochemical electrodes.