Electrospun nanosystems based on PHBV and ZnO for ecological food packaging

The electrospun nanosystems containing poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and 1 wt% Fe doped ZnO nanoparticles (NPs) (with the content of dopant in the range of 0–1 wt% Fe) deposited onto polylactic acid (PLA) film were prepared for food packaging application. They were investigated by scanning electron microscopy (SEM), energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), antimicrobial analysis, and X-ray photoelectron spectrometry (XPS) techniques. Migration studies conducted in acetic acid 3% (wt/wt) and ethanol 10% (v/v) food simulants as well as by the use of treated ashes with 3% HNO3 solution reveal that the migration of Zn and Fe falls into the specific limits imposed by the legislation in force. Results indicated that the PLA/PHBV/ZnO:Fex electrospun nanosystems exhibit excellent antibacterial activity against the Pseudomonas aeruginosa (ATCC-27853) due to the generation of a larger amount of perhydroxyl (¿OOH) radicals as assessed using electron para-magnetic resonance (EPR) spectroscopy coupled with a spin trapping method. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

INFRARED SPECTRA OF CALCIUM PHOSPHATE GLASSES

Infrared absorption spectra of calcium phosphate glasses, x CaO ·(100-x) P 2 O 5 have been investigated by FT-IR spectroscopy. By increasing CaO content, the characteristic bands due to the stretching and bending vibrations were identified and analyzed. The deconvolution of each experimental spectrum was made using a Gaussian-type function. Based on this, the specific structural units of these glasses were identified. </jats:p