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In this paper, 2-hydroxyethyl methacrylate (HEMA) was graft copolymerized onto chitosan (CHI) at different ratios using a radical initiator. The grafted hydrogel composites were then characterized by attenuated total reflection Fourier transform ınfrared spectroscopy (ATR-FTIR) and thermo-gravimetric analysis (TGA). Swelling behavior of the hydrogels was investigated at different pH and different times. The antimicrobial activity of the chitosan-graft-HEMA (CHI-HEMA) against gram-negative bacteria and gram-positive bacteria was studied by the standard agar well diffusion assay method. The CHI-HEMA 1:1 and CHI-HEMA 1:2 showed an obvious antimicrobial effect against six test strains. The CHI-HEMA 1:1 and CHI-HEMA 1:2 exhibited a highly significant increase (p < 0.01) in diameter of the inhibition zones compared with the standard antibiotics. Furthermore, CHI-HEMA 1:1 presented the highest antimicrobial activity against all test strains with a significant difference (p < 0.01) compared with CHI-HEMA 1:2. Meanwhile, the decreasing order of the average sensitivity to CHI-HEMA 1:1 and CHI-HEMA 1:2 was observed to be S. marcescens > E. coli > S. aureus subsp. aureus > S. enteritidis > E. faecalis > E. aerogenes. These results indicate potential application of CHI-HEMA 1:1 and CHI-HEMA 1:2 graft hydrogels as a novel and efficient antimicrobial agent in biomedical fields.

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The current study focuses on the fabrication, characterization, and cytotoxic effects of polymeric biocomposite films composed of starch, various concentrations of citric acid (3%, 6%, and 9%), and polyvinyl alcohol. The cross‐linked corn starch (S)‐polyvinyl alcohol (P) biocomposite films are prepared by casting technique using glucose (G) and fructose (F) as plasticizers. The chemical structure of obtained films is characterized by Fourier transform infrared and x‐ray diffraction. Physicochemical parameters of the films such as solubility, swelling capacity, and water vapor permeability, optical and mechanical properties are investigated. Furthermore, the cytotoxicity is evaluated to determine the biocompatibility of samples. The physicochemical properties of S‐P(Starch‐Polyvinyl alcohol) films improve with the addition of citric acid during the esterification reaction. The tensile strength for Starch‐Polyvinyl alcohol‐Glucose blend composition with 3% citric acid (SPG3) and Starch‐Polyvinyl alcohol‐Fructose blend composition with 3% citric acid (SFG3) biocomposite films is determined as 10.17 and 8.24 MPa, respectively, compared to 8.16 and 7.94 MPa for without citric acid, respectively. The cell viability values of biocomposite films towards NIH‐3T3 and L929 cells are calculated 90% compared to the control group. Thus, it demonstrates that they are also quite biocompatible materials.

In this study, PSG composite films were prepared by casting method by adding graphene (G) to glycerol plasticized potato starch (PS) films. The structure and properties of the composite films were investigated attenuated total reflectance Fourier transform infrared (ATR‐FTIR), X‐ray analysis (XRD), and swelling capacity, total soluble matter, transparency, tensile strength, and electrical conductivity. When the G content of PSG composite films increased from 0% to 1%, tensile strength increased from 1.035 MPa to 1.681 MPa, but decreased to 1.175 MPa in composite films containing 2% G. It also increased electrical conductivity when the G concentration increased. Also, the G layers are among the PS films and their swelling and solubility properties are reduced. With increased G concentration, the light transmittance decreased and the films were more opaque. These improvements can refer to the interface interaction between PS and G.

Potato starch (PS) films reinforced with microcrystalline cellulose (MCC) were prepared with casting solution, and the effect of montmorillonite (MMT) clay in different proportions (1, 3, 5 and 10 wt%) using nanofiller was established. The films were investigated by Fourier transform ınfrared (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), tensile strength, opacity, colour, water vapour permeability and solubility. Tensile strength for nanocomposite films depending on the clay content was increased significantly from 0.64 to 1.89 MPa. The water vapour permeability of nanocomposite films was improved compared to the PSMCC blend without MMT. Also, dielectric properties and electrical conductivity of films were studied. The dielectric permittivity (έ), the dielectric loss (ε˝) and the electrical conductivity (σ) increased with increasing MMT content at frequencies between 100 Hz to 10 kHz. This nanocomposite with improved functional properties could be used in potential food packaging materials and electrical applications.

In this study, chitosan (C)/gelatin(G)/starch(S) composites incorporated pineapple peel extract (PPE) and aloe vera gel (AVG) were prepared by the casting method as antioxidant agents. Mechanical, water vapor permeability (WVP), moisture content, solubility, opacity, and color properties of the effects of PPE and AVG at different concentrations (0%, 10%, and 30%) were investigated.The prepared films were characterized by Fourier transform infrared spectroscopy in attenuated total reflection (ATR-FTIR), X-ray diffraction (XRD), Thermal gravimetric analysis (TGA), Scanning electron microscope (SEM), mechanical, water barrier, opacity, and color. PPE and AVG extract incorporated edible films improved thermal stability of edible films. Tensile strength decreased with the addition of extracts; the maximum tensile strength was 8.15 MPa for CGS film. The WVP of the films increased with the increasing PPE and AVG concentration. As a biological activity, the films inhibited the growth of gram-positive (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli). With the addition of PPE and AVG to the CGS film, its antioxidant properties were enhanced. In addition, the prepared films were applied for strawberry coating both in the refrigerator and at room temperature. Consequently, these edible-coated films can be used for active food packaging/ coating to extend the shelf life of fruits.