Enhancing optical properties and antimicrobial efficacy of PEO/CS‑doped TiO2 nanoparticles for food packaging applications

including polyethylene oxide and chitosan (PEO/CS) doped with titanium dioxide
nanoparticles (
TiO2 NPs) as nanoceramic were successfully synthesized. The study
investigated how varying TiO2
nanoparticle concentrations influenced the structural,
optical properties, and antibacterial activity of the polymeric matrix. XRD patterns
revealed an increase in the amorphous nature of the polymer blend as the content of
TiO2
NPs inside the PEO/CS blend grew. The FT-IR analysis confirmed the interaction
between TiO2
NPs and the PEO/CS blend. This confirmation is attributed
to the observed vibrational changes upon the incorporation of TiO2
dopant into the
polymer matrix. The UV–visible spectrum aided in the determination of optical
energy band gaps (both direct and indirect), showing reductions in both Egd and Egin
with higher TiO2
concentrations. SEM highlighted the partial compatibility between
PEO/CS and TiO2,
while transmission electron microscopy depicted spherical TiO2
NPs with diameters ranging from approximately 9 to 25 nm. Antimicrobial assessments
indicated heightened efficacy in all nanocomposite samples compared to the
pure PEO/CS composite, with a linear correlation to the quantity of TiO2
nanoparticles
present. These findings strongly suggest the potential of these nanocomposites
for food packaging applications.