Optimizing magnetic, dielectric, and antimicrobial performance in chitosan-PEG-Fe2O3@NiO nanomagnetic composites.

There is a growing interest in eco-friendly and cost-effective organic-inorganic nanocomposites due to their alignment with the principles of "green" chemistry, as well as their biocompatibility and non-toxicity. This study focused on producing Chitosan-PEG-Fe 2 O 3 @NiO nanomagnetic composites to improve the stability, dielectric properties, and antimicrobial effectiveness of these nanocomposite materials. The process involved synthesizing Fe 2 O 3 @NiO via sol-gel and polymerizing chitosan-PEG. The nanocomposites were characterized by XRD, TEM, FTIR, optical, dielectric, and VSM. Incorporating Fe 2 O 3 @NiO significantly improved stability, and the interaction with Fe2O3 during the sol-gel process facilitated the formation of NiFe 2 O 4 with an increase in the crystallinity within the chitosan-PEG matrix. The study examined optical and dielectric properties, highlighting that the 3 NiO-doped chitosan-PEG-Fe 2 O 3 composites had high electrical conductivity (1.8 ∗ 10−3 S/cm) and a significant dielectric constant (106 at low frequencies). As the ratio of NiO NPs within the chitosan-PEG-Fe 2 O 3 increases, the energy band gap of chitosan-PEG-Fe 2 O 3 films decreases up to 3.7 eV. This decrease is owing to the quantum confinement effect. These composites also demonstrated improved antimicrobial activity against E. coli and S. aureus and higher activity in the presence of nanomagnetic particles. The minimum inhibitory concentrations of CS-PEG-Fe 2 O 3 /NiO NPs against (Bacillus cereus , M. luteus , S. aureus and (S. enterica , H. pylori , E. coli) were (22–35 mm) and (21–34 mm), respectively. [ABSTRACT FROM AUTHOR]