Biocompatible and flexible transparent electrodes for skin-inspired sensing

In the last years, flexible electronics have suffer a massive growth as a response to the high demand of new skin patch sensor devices targeted for personnel health monitoring. In this context, the incorporation of biological polymers in the backbone of these soft systems brings new opportunities in terms of biocompatibility and sustainability performance. However, the suitable integration of a conductive patterned material is still a challenge in order to achieve good adhesion and high transparency. Thus, silver nanowires (AgNWs) constitute promising candidates for the fabrication of flexible transparent conductive films. Herein, a chitosan membrane doped with a plasticizer element was made conductive, through a one-step process, by using an optimized ratio of chitosan-lactic acid-AgNWs dispersion. This formulation was applied by screen printing technique and the influence of polymer ratio, cure temperature and number of layers applied with the AgNW-based ink was investigated. Compared to the conventional water-based AgNW dispersions, the here proposed chitosan-doped ink enabled the fabrication of transparent electrode platforms holding good stability, homogeneity and electrical features.