Synthesis and characterization of antimicrobial colloidal polyanilines

The potential application of colloidal polyaniline (PANI) as an antimicrobial is limited by challenges related to solubility in common organic solvents, scalability, and antimicrobial potency. To address these limitations, we introduced a functionalized PANI (fPANI) with carboxyl groups through the polymerisation of aniline and 3-aminobenzoic acid in a 1:1 molar ratio. fPANI is more soluble than PANI which was determined using a qualitative study. We further enhanced the solubility and antimicrobial activity of fPANI by incorporating Ag nanoparticles onto the synthesized fPANI colloid via direct addition of 10 mM AgNO3. The improved solubility can be attributed to an approximately 3-fold reduction in size of particles. Mean particle sizes are measured at 1322 nm for fPANI colloid and 473 nm for fPANI-Ag colloid, showing a high dispersion and deagglomeration effect from Ag nanoparticles. Antimicrobial tests demonstrated that fPANI-Ag colloids exhibited superior potency against Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli, and Bacteriophage PhiX 174 when compared to fPANI alone. The minimum bactericidal concentration (MBC) and minimum virucidal concentration (MVC) values were halved for fPANI-Ag compared to fPANI colloid and attributed to the combination of Ag nanoparticles with the fPANI polymer. The antimicrobial fPANI-Ag colloid presented in this study shows promising results, and further exploration into scale-up can be pursued for potential biomedical applications

Antimicrobial photocatalytic PANI based-composites for biomedical applications

Surface contamination and transmission can lead to Hospital Acquired Infections (HAI) in a healthcare environment. To tackle this problem, a sustainable antimicrobial coating is desirable. Photocatalytic coatings with titanium dioxide (TiO2) as the main component activated by UV light are one option. In order to implement the coating in a real-world hospital setting the photocatalytic component must show activity under visible light. In this article the TiO2 photocatalyst was synthesised as both 2- and 3- component composites with polyaniline (PANI) or poly(aniline-co-3-aminobenzoic acid) (fPANI) and Ag nanoparticles to achieve photocatalytic performance activated by visible light. The UV-DRS results supported the visible light photocatalytic capability of both 2- and 3-component composite systems, and the ESR spectra exhibited the presence of charge carriers (unpaired electrons), which was confirmed by conductivity studies. The intensity of the ESR peak increases around 3-fold for PANI/fPANI-TiO2-Ag composites compared to pure PANI/fPANI. The conductivity of pure PANI and fPANI was only mildly enhanced in 3-component systems, which could be due to presence of TiO2, whereas the value increased by around three times for PANI/fPANI-Ag 2-component system due to conductive Ag nanoparticles. The composites with fPANI showed improved antimicrobial activity than PANI composites against three representative microorganisms Escherichia coli, Staphylococcus aureus and a model viral strain bacteriophage Phi X 174. Finally, we proposed a mechanism for photocatalytic activity for both 2- and 3- component systems

Enhanced microwave synthesis of polyaniline nanomaterials

Energy- and time-efficient enhanced microwave syntheses (EMS) of polyaniline (PANI) have been carried out. The GPC results showed that the molecular weight of the microwave-generated materials depends on the applied microwave power. FTIR spectroscopies confirmed the formation of PANI. The presence of a mixed morphology with the prevalence of nanofibers with different aspect ratios is confirmed through SEM. The conductivity of the samples (ca. 3-3.5 S cm-1) is found to be relatively independent on the microwave power levels. The fact that the molecular weight depends on the power means that this approach can be fine-tuned to optimize conditions for a specific material using different power levels

Pseudocapacitance behavior of polyaniline in aerated HC1 and H2SO4 solutions

High conducting polyaniline (PANI) nanofibres deposited onto glassy carbon support were studied in sulphuric (1mol dm-3 H2SO4) and hydrochloric (1mol dm-3 HCl) acid by both potentiodynamic and complex impedance methods. A large charge storage capacity was obtained in each of investigated acid solutions, particularly in HCl one. For instance, specific capacity amounting to 340 Fg-1 was observed potentiodynamically in 1mol dm-3 HCl at a scan rate of 10 mVs-1

Microwave assisted synthesis of polyaniline/pullulan (pani/pull) composite

Microwave assisted synthesis of polyaniline modified by pullulan (PANI/Pull) composite was performed by aniline oxidation with potassium iodate. The PANI/Pull composite was characterized using ATR-FTIR technique. FTIR spectra confirm presence of both components in PANI/Pull composite. Antimicrobial evaluation of PANI/Pull material performed by using a qualitative disk diffusion method on Candida albicans (C. albicans) culture showed very high sensitivity to PANI/Pull composite. Observed FTIR and antifungal activity represent a promising results especially for potential biomedical applications of PANI/Pull composite.Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/4956

Microwave assisted synthesis of polyaniline/pullulan (pani/pull) composite

Poster presented at Physical Chemistry 2021, 15th International Conference on Fundamental and Applied Aspects of Physical ChemistryAbstract: [https://cer.ihtm.bg.ac.rs/handle/123456789/4955

Microwave assisted synthesis of polyaniline/pullulan (pani/pull) composite

Microwave assisted synthesis of polyaniline modified by pullulan (PANI/Pull) composite wasperformed by aniline oxidation with potassium iodate. The PANI/Pull composite was characterizedusing ATR-FTIR technique. FTIR spectra confirm presence of both components in PANI/Pullcomposite. Antimicrobial evaluation of PANI/Pull material performed by using a qualitative diskdiffusion method on Candida albicans (C. albicans) culture showed very high sensitivity toPANI/Pull composite. Observed FTIR and antifungal activity represent a promising results especiallyfor potential biomedical applications of PANI/Pull composite.Poster: [https://cherry.chem.bg.ac.rs/handle/123456789/5431

Microwave assisted synthesis of polyaniline/pullulan (pani/pull) composite

Poster presented at Physical Chemistry 2021, 15th International Conference on Fundamental and Applied Aspects of Physical ChemistryAbstract: [https://cherry.chem.bg.ac.rs/handle/123456789/5430