Chemical oxidative polymerization of conductive polyaniline-iron oxide composite as an electro-transducer for electrochemical sensing applications

Abstract

This study explored the preparation of conductive polyaniline-iron oxide (PANI-Fe2O3) that served as the electrical signal transducer, to convert the electrochemical interactions between the biotinylated-goat-anti-mouse IgG (b-IgG) and bovine serum albumin (BSA) into a measurable resistance signal. In this study, PANI was synthesized through the oxidative polymerization of aniline monomer (AM) in the presence of ammonium persulfate (APS) as the oxidizing agent. Concentration effects of AM and volume ratios of AM:APS were evaluated so as to obtain higher conductivity performance in an electrochemical sensing application. The synthesized PANI composites were analyzed through conductivity measurement. The conductive PANI-Fe2O3-GA-b-IgG bio-conjugates was then interacted with BSA, relays the antigen-antibody binding as a measured electrical detection in an assembled pulse-mode electrochemical biosensor. In present work, 0.2 m of AM with 1:3 volume ratio of AM:APS has contributed to the optimal ionic conductivity property of PANI, with excellent electrochemical sensing performance recorded at 3.538±0.067 mΩ.

Morphological characteristics of polymeric nylon‐6 film as biological recognition interface for electrochemical immunosensor application

“…Fe 2 O 3 was used as a separation agent to collect the successful conjugated PANI‐Fe 2 O 3 nanocomposite from the unconjugated polyaniline (PANI) solution. The reaction was conducted in an incubated shaker at 27 °C for 4 h, until the solution changed its color from rust brown (the Fe 2 O 3 suspension color) to dark green, indicating the production of conductive polyaniline emeraldine salt . Methanol was then added to quench the polymerization.…”

Fe3O4-Polyaniline Nanocomposite for Non-enzymatic Electrochemical Detection of 2,4-Dichlorophenoxyacetic Acid

“…2,12−14 Polyaniline (PANI) with its versatile properties has emerged as a potential conducting polymer in the field of electrochemistry and sensing. 2,12,15,16 because of their high surface area, π-conjugated structure, excellent redox properties, and presence of amine groups. 17 However, they have certain limitations due to their poor solubility in common organic solvents, instability at higher temperature, poor electrochemical stability, reproducibility, and selectivity.…”

“…23 To overcome these limitations, development of organic−inorganic hybrid nanocomposites of metal oxides and conducting polymers may be promising for commercial development of cost-effective electrochemical sensors. 16 Currently, the detection of 2,4-D is based on an enzyme immobilization technique. 4,27−29 Despite its popularity, an enzyme-based sensing technique comes with certain operational limitations such as high cost, thermal and chemical instability, loss of enzyme bioactivity, short lifetime, and low reproducibility.…”

“…Conducting polymers have potential sensing applications owing to their flexibility, high sensitivity, excellent redox properties, low cost, and ability to perform at room temperature. ,− Polyaniline (PANI) with its versatile properties has emerged as a potential conducting polymer in the field of electrochemistry and sensing. ,,, PANI-based composites have a great deal to offer as sensing materials because of their high surface area, π-conjugated structure, excellent redox properties, and presence of amine groups . However, they have certain limitations due to their poor solubility in common organic solvents, instability at higher temperature, poor electrochemical stability, reproducibility, and selectivity. ,− On the other hand, transition metal oxide nanoparticles owing to their electrocatalytic activities and strong adsorption abilities have received tremendous attention in electrochemical and bio-sensing applications. − Among various metal oxides, iron oxide (Fe 3 O 4 ) nanoparticles are gaining more attention in bio-sensing applications due to their favorable band gap, biocompatibility, nontoxicity, thermal stability, interesting optical and magnetic properties, and high natural abundance. ,, Fe 3 O 4 nanoparticles have novel prospects in the field of electrochemical sensing because of their high electrical conductivity even at room temperature due to electron exchange between Fe 2+ and Fe 3+ ions. , However, metal oxides require high temperature for sensing performance .…”

Thermal Mechanical Stretching to Imprint Pores Morphology of Nitrocellulose Membrane for Immuno-sensing Application

“…The principal analysis of an immunoassay is based on the specific interactions between a substance of interest (target analyte) and the biological recognition elements (capture analyte such as enzymes, antibodies, nucleic acids, etc.) that are immobilized on the lateral flow membrane [4].…”