Insights into vertically aligned carbon nanofiber (VACNF) (bio)electrodes and their application potential – An overview

Vertically aligned carbon nanofibers (VACNFs) hold great promise for biosensing and energy storage applications. Building upon a decade of our groups research and incorporating new experimental insights, this work presents a synthesis of VACNF performance as bioelectrodes, revealing a key unifying factor: the length of the VACNFs. Our analysis spans multiple dimensions—physicochemical properties, electrochemical behavior, and biological interactions—demonstrating how this single parameter plays a fundamental role across all aspects critical to the successful implementation of VACNF-based biosensors. We explore the impact of adhesion layers and catalyst metals on VACNF growth, influencing their macro- and nanoscale morphology. We further examine how macroscopic features such as density and alignment affect electroanalytical performance, particularly in terms of sensitivity and selectivity. Additionally, we investigate the nanoscale characteristics of VACNFs and their role in detecting key biomolecules, including dopamine, ascorbic acid, and uric acid. Beyond electrochemistry, we discuss how VACNFs facilitate neural cell guidance, underscoring their significance in neural interfacing and biomedical applications. Through this comprehensive synthesis, we identify VACNF length as a decisive factor that transcends chemistry, electrochemistry, and biocompatibility—serving as a fundamental variable for optimizing VACNF-based biosensors. This new perspective provides a straightforward and powerful approach to enhancing biosensor performance, offering a unifying principle that streamlines future research and application development.