Improved conductive carbon nanotube tape using natural cellulose fibrils for array tomography

Array tomography using scanning electron microscopy (SEM) enables large-volume, nanometer-scale reconstruction of neural circuits and allows nanometer resolution of synaptic vesicles and other ultrastructural features. For stable serial imaging, Kapton tape, carbon nanotube (CNT) tape mounted on silicon wafers, and indium tin oxide (ITO) glass have commonly been used. However, each tape shows practical limitations: CNT tape is not consistently available, whereas Kapton tape often requires additional glow discharge or carbon coating steps to reduce charging artifacts and improve imaging stability.Here, we report the development of a lab-made tape using a cellulose/CNT/AgNW composite tape designed for SEM-based array tomography. By integrating intrinsically hydrophilic natural cellulose fibrils with conductive carbon or silver nanotubes, the newly developed tape provides sufficient surface hydrophilicity and conductivity without additional glow discharge or carbon coating treatment. This simplifies workflow while maintaining stable imaging conditions. Notably, the cellulose fibrils containing tape demonstrated reduced charging artifacts, improved section adhesion, and stable high-resolution imaging suitable for nanometer level analysis. Our results establish cellulose-based conductive tape as a practical advancement for array tomography, enhancing reliability and reproducibility in large-scale SEM imaging.