Efficient fabrication of poly(pyrrole)-nanowires through innovative nanocontact printing, using commercial CD as mold, on flexible thermoplastics substrates: Application for cytokines immunodetection

Poly(pyrrole)-nanowires (PPy-NWs) were efficiently printed by using nano printing on flexible thermoplastics, and then used to device an impedimetric immunosensor. The present pioneering technology allow to create high sensitive and disponsable immunosensor devised using a low cost and simple fabrication. The innovative nanocontact printing uses a PDMS stamp replicated from a CD mold. The PPyNW printing uses controlled chemical polymerization to print PPy-NWs on poly (ethylene terephthalate) and polyether ether ketone surfaces. Atomic force microscopy analysis of PPyNW revealed a width, height and a separation length of 125 ± 8 nm, 377 ± 5 nm and 172 ± 4 nm, respectively. The PPy-NWs were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS). The XPS results evidenced the covalent bonding between the thermoplastic surface and the PPyNWs. As a final point, the immunosensor was tested for the quantification of Interleukin 6 recombinant human (IL6, Ag) using EIS. The PPy-NWs were functionalized via diazonium coupling reaction and carbodiimide crosslinker chemistry for the immobilization of Anti-human IL-6 monoclonal antibodies (IL6 mAb's). The developed immunosensor exhibited a sensitivity of 0.013 (pg/mL)⁻¹ (linear fitting at R² = 0.99) and limit of detection (LOD) of 0.36 pg/mL in a linear range of 1–50 pg/mL for Ag IL-6, with a relative standard deviation percentage (RSD%) at 7.6%.