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A highly performant patterning of antibodies using poly(pyrrole) nanowires (PPy-NWs) was devised on thermoplastic surfaces based on silane derivatives. The PPy-NWs were fabricated employing nanocontact printing and controlled chemical polymerization (nCP-CCP) on poly(ethylene terephthalate), cyclic olefin copolymer, poly(ethylene 2,6-naphthalate), and polyimide. The technique used a commercial compact disk as a template (mold) to produce nanopatterned polydimethylsiloxane stamps. The nanopatterned stamp was then employed to print PPy-NWs. The printing technique permits to control PPy-NW size and shape. The dimensions of the printed PPy-NWs were: 785 ± 1.5 nm (width), 174 ± 2.1 nm (height), and a separation between wires of 540 ± 1.2 nm. The printing process and the surface properties of the PPy-NWs pattern were successfully characterized by scanning electron microscopy and atomic force microscopy. Biopatterning was completed by the chemical immobilization of the specific anti-human interleukin-10 monoclonal antibody on PPy-NW using gluteraldehyde. The biocomposite was tested using qualitative immunocytokine bioassay, which is of great importance for early stage cancer detection. For that purpose, fluorescent imaging was used to certify the immunodetection of the recombinant human interleukin-10. The biopatterning technology provides a simple, low cost and one step procedure. Undoubtedly, this new technology will impact and provide an alternative to the current techniques applied for bioengineering and nanopatterning. [ABSTRACT FROM AUTHOR]

In this research, an efficient fabrication process of conducting polypyrrole (PPy)/silicon nitride (Si3N4) hybrid materials were developed in order to be employed as transducers in electrochemical sensors used in various environmental and biomedical applications. The fabrication process was assisted by oxidative polymerization of pyrrole (Py) monomer on the surface of Si/SiO2/Si3N4 substrate in presence of FeCl3 as oxidant. To improve the adhesion of PPy layer to Si3N4 surface, a pyrrole-silane (SPy) was chemically bonded through silanization process onto the Si3N4 surface before deposition of PPy layer. After Py polymerization, Si/SiO2/Si3N4-(SPy-PPy) substrate was formed. The influence of SPy concentration and temperature of silanization process on chemical composition and surface morphology of the prepared Si/SiO2/Si3N4-(SPy-PPy) substrates was studied by FTIR and SEM. In addition, the electrical properties of the prepared substrates were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It was found that the best silanization reaction conditions to get Si/SiO2/Si3N4-(SPy-PPy) substrate with high PPy adhesion and good electrical conductivity were obtained by using SPy at low concentration (4.3 mM) at 90°C. These promising findings open the way for fabrication of new hybrid materials which can be used as transducers in miniaturized sensing devices for various environmental and biomedical applications. [ABSTRACT FROM AUTHOR]

We present a new low-cost technology to fabricate poly(pyrrole) microwires (PPy-μWs) by micro contact printing (μCP) and controlled chemical polymerization (μCP-CCP) using three different techniques (“ grafting printing ”, “ addressed printing ”, and “ direct printing ”. These developed techniques provide a platform to regulate PPy wire size and shape using N-(3-trimethoxysilyl-propyl) pyrrole (Py-silane) for the “ addressed printing ” and “ direct printing ” techniques, respectively. The technique uses a silicon mold to produce micropatterned polydimethylsiloxane (PDMS) stamps. The micropatterned PDMS stamp was employed to print PPy-μWs with an improvement observed from “ direct printing ” > “ addressed printing ” > “ grafting printing ”. Therefore, for “ direct printing ”, PPy-μWs were printed on: poly(ethylene terephthalate) (PETE), cyclic olefin copolymer (COC), poly(ethylene 2,6-naphthalate (PEN), and polyimide (PI) surfaces. Here, we have studied the printing of wires and the surface morphology to understand the characteristics of PPy patterns by optical microscopy, scanning electrode microscopy (SEM), and atomic force microscopy (AFM). The functionality of the PPy-μW matrix was also analyzed for immune detection. Here, fluorescent imaging was used to certify the detection of recombinant human interleukin-10 (rh IL-10). PPy-μWs were functionalized using gluteraldehyde (GA) for the specific immobilization of anti-human interleukin-10 monoclonal antibodies (anti-IL-10 mAb's). The immunosensor present a sensitivity of 0.026 (pg/mL −1 ) to the respective rh IL-10 in a linear range of 1–50 pg/mL and a limit of detection at 0.36 pg/L. Finally the PPy-μW matrix was successfully tested for cytokine bioassays using electrochemical impedance spectroscopy (EIS) and presents outstanding properties as a matrix for biosensing. [ABSTRACT FROM AUTHOR]