Electroactive polyamide/cotton fabrics for biomedical applications

The latest advances on the development of wearables electrochemical sensors and biosensors has been revolutionizing healthcare, allowing a faster and specific diagnosis of pathological condition. The purpose of this work was to develop the first stage of wearable conductive based-textiles using natural (cotton) and synthetic (polyamide) fabrics composed of the conductive polypyrrole and polyaniline polymers. Conductive polymers were polymerized in situ within fabrics using the correspondent monomers (pyrrole, Py and aniline, ANi) and an oxidizing agent (ammonium persulfate, APS). The obtained fabrics were characterized in terms of microstructure, hydrophobicity, chemical composition, color fastness of domestic and industrial washing, color fastness to rubbing and cytotoxicity. Optimal conductivity vales (10−6<σ < 10−4) were attained in PPy and PANi fabrics using 2:1 ratio (0.5 M Py and 0.25 M APS) and 1:1 ratio (0.5 M ANi and 0.5 M APS), respectively. Textiles maintained their morphological integrity upon the polymerization process and, in some conditions, presented hydrophobicity (θ > 90°for PA/CO fabrics containing PPy and CO fabrics containing PANi; θ < 90° for Bleached PA and PA fabrics containing PANi). The surface and volumetric conductivities of fabrics containing PPy or PANi were not affected after the color fastness to domestic and industrial washing and to rubbing testing's, except CO fabrics containing PANi. Cell viability was higher than ≈70% in both synthetic and natural fabrics containing PPy or PANi, with the exception of natural fabrics containing PANi that revealed a cell viability less than ≈50%. In conclusion, this study demonstrates the development and characterization of conductive based-textiles using synthetic and natural fabrics containing PPy and PANi with great potential to be used in future biomedical applications.

The authors thank the funds provided by FEDER funds throughOperationalProgramme for Competitiveness Factors–COMPETE and National Funds through FCT–Foundation for Science and Technologywithin the scope of the projects POCI-01-0145-FEDER-007136 and UID/CTM/00264 and the grant POCI-01-0145-FEDER-007038-UMINHO/BPD/44/2016 (LPS), and by the project FROnTHERA(NORTE-01-0145-FEDER-000023), supported by Norte PortugalRegional Operational Programme (NORTE 2020), under thePORTUGAL 2020 Partnership Agreement, through the EuropeanRegional Development Fund (ERDF).