Chitosan coatings onto polyethylene terephthalate for the development of potential active packaging material

Effect of caraway essential oil on the antioxidant and antimicrobial activity of chitosan film

“…A peak at 1646 cm -1 is assigned to the presence of carbonyl group (C=O) in chitosan film (Martins et al, 2012;Zemljič et al, 2013). Since the grade of chitosan used in the present study was around 80% deacetylated, the C=O stretching (amide I) peak at 1650 cm -1 and N-H bending (amide II) peak at 1580 cm -1 were observed.…”

“…Interval at 3500-3000 cm -1 corresponds to stretching vibration of free hydroxyl group that overlaps the asymmetric and symmetric stretching of the N-H bonds in amino group in the same region in chitosan spectra (Altiok et Zemljič et al, 2013). No significant differences were observed in chitosan spectrum after incorporating 1% of CEO.…”

“…Chitosan film without incorporated CEO was used as a control. The degree of reduction of cell number of tested bacteria was investigated and only films that showed AA higher than 75%, were considered to have significant inhibitory activity (Zemljič et al, 2012;Zemljič et al, 2013).…”

Relevant insight of surface characterization techniques to study covalent grafting of a biopolymer to titanium implant and its acidic resistance

“…6a). The weak band at 2876 cm −1 corresponds to (-CH 2 -) stretching while bands at 1634, 1558, 1375 and 1315 cm −1 are attributed to C=O of amide, -NH 2 stretching vibration, -NHCO of amide and -C-N, respectively [51,56]. The bands at 1150, 1070, 1019 and 893 cm −1 are characteristics of chitosan structure [51,56,57].…”

“…Absence of titanium suggests a chitosan thickness superior to 10 nm (XPS detection limit). The deconvoluted peaks of C 1s and O 1s of CSAPiTi sample gave four and two peaks, respectively (see Table S1 in supplementary data): peaks at 284.6 eV (30.4 ± 4.0%), at 286.1 eV (51.5 ± 2.4%), at 287.8 eV (15.7 ± 1.5%), and at 289 eV (1.9 ± 0.1%) were assigned to C-C/C-H, C-N/C-O, O-C-O/C=O and N-C=O, respectively, for C 1s signal [29,51] and peaks at 531.5 eV (99.2 ± 0.1%) and at 532.5-533 eV (0.8 ± 0.1%) which were assigned to O=C-N and O-C, respectively [52,53]. The deconvoluted N 1s signal gave two peaks at 399.3 and at 401.5 eV corresponding to -NH 2 and -NH 3 + , respectively.…”