High-performance competence of polyaniline-based nanomaterials

Conjugated Polymer/Graphene Oxide Nanocomposites—State-of-the-Art

Graphene oxide is an imperative modified form of graphene. Similar to graphene, graphene oxide has gained vast interest for the myriad of industrial applications. Conjugated polymers or conducting polymers are well known organic materials having conducting backbone. These polymers have semiconducting nature due to π-conjugation along the main chain. Doping and modification have been used to enhance the electrical conductivity of the conjugated polymers. The nanocomposites of the conjugated polymers have been reported with the nanocarbon nanofillers including graphene oxide. This review essentially presents the structure, properties, and advancements in the field of conducting polymer/graphene oxide nanocomposites. The facile synthesis, processability, and physical properties of the polymer/graphene oxide nanocomposites have been discussed. The conjugated polymer/graphene oxide nanocomposites have essential significance for the supercapacitors, solar cells, and anti-corrosion materials. Nevertheless, the further advanced properties and technical applications of the conjugated polymer/graphene oxide nanocomposites need to be explored to overcome the challenges related to the high performance.

Experimental and Computational Studies of Azo Dye-Modified Luminol Oligomers: Potential Application in Lithium Ion Sensing

With a view to design novel conjugated oligomers via a facile technique for its possible application in sensors, the present work reports oligomerization of Bismarck Brown (BB) dye with luminol. The structure was confirmed via IR studies, while the electronic transitions were confirmed by UV-visible studies. Morphological studies were carried out via SEM. Computational studies were carried out using the DFT method with a B3LYP 6-311G(d) basis set to investigate the optimized geometry, band gap, and vibrational and electronic transitions data. The HOMO-LUMO energies showed significant reduction in the band gap upon increasing the content of BB dye. The computational IR and UV spectra were noticed to be in close agreement with the experimental results. Spectrophotometric determination of Li ion was attempted using lithium chloride and a lithium carbonate drug commonly used in the treatment of bipolar disorder. The detection limit was noticed to be as low as 5.1 × 10-6 M, which could be used to design a Li ion sensor.

One-step modification of nano-polyaniline/glucose oxidase on double-side printed flexible electrode for continuous glucose monitoring: Characterization, cytotoxicity evaluation and in vivo experiment

The single-step modification of the nanostructured polyaniline (PANI)/glucose oxidase (GOD) enzyme on double-sided, screen-printed, flexible electrodes doped with Prussian blue (PB), has been achieved and successfully applied in continuous glucose monitoring in vivo, and its biocompatibility has been evaluated systematically. The proposed fabrication procedure is simple, low cost, and suitable for large-scale production. PB doped with carbon ink catalyzes the reduction of hydrogen peroxide (H₂O₂) in low-voltage conditions, which could help eliminate interferences. And the PANI/GOD nanostructure makes the GOD enzyme more stable for long-term, in vivo monitoring. More importantly, a polyurethane (PU) layer is deposited on the electrode's surface as a diffusion limiting membrane that enhanced the linear range and biocompatibility. In tests in vitro, the proposed biosensor achieved a linear range of 0-12 mM and a good sensitivity of 16.66 μA·mM^-1·cm^-2(correlation coefficient R² = 0.9962) with an excellent specificity to glucose. The biosensor exhibits long-term stability, with a maximum lifespan of 14 days when stored in phosphate buffer solution at 4 °C, and achieves a sensitivity of 120%. The biocompatibilities of the electrode materials have also been systematically evaluated in cytotoxicity and cell adhesion tests to ensure the safety of implantation. In experiments in vivo, the biosensor can successfully monitor the glucose level fluctuation of rats after 24 h following implantation. Overall, the biosensor fabricated with the double-side, screen-printing process, satisfies the glucose monitoring range in vivo and eliminates various types of interference, thus establishing a new, large-scale production procedure for flexible in vivo biosensors.