Oxygen Permeability Research Articles

Impact of Citric Acid on the Structure, Barrier, and Tensile Properties of Esterified/Cross-Linked Potato Peel-Based Films and Coatings

The valorization of potato peel side streams for food packaging applications, especially for the substitution of current petrochemical-based oxygen barrier solutions such as EVOH, is becoming increasingly important. Therefore, potato peel-based films and coatings (on PLA) were developed containing 10–50% (w/w potato peel) citric acid (CA). To determine the impact of CA concentration on the structure and physicochemical properties of cast films and coatings, ATR-FTIR spectroscopy, moisture adsorption isotherms, tensile properties, light transmittance, oxygen permeability, carbon dioxide transmission rate, and water vapor transmission rate measurements were performed. The results indicate that an increase in CA concentration from 10% to 30% increased esterification/cross-linking and resulted in minimal values for the oxygen permeability (0.08 cm3 m−2 d−1 bar−1) at 50% RH and water vapor transmission rate (1.6 g m−2 d−1) at 50% → 0% RH, whereas an increase from 30% to 50% increased free CA concentration and resulted in increased flexibility, indicating that CA functioned as a plasticizer within the film/coating at higher concentrations. Overall, potato peel-based coatings containing CA showed comparable barrier properties to EVOH. We assume that an extensive industrial purification or fractionation of potato peel, which was not carried out in this study, could lead to even lower transmission rates.

Preparation and Characterization of Chitosan‐Tremella fuciformis Polysaccharide Edible Films for Meat Preservation

ABSTRACTThe objective of this research was to develop and analyse a chitosan‐Tremella fuciformis polysaccharide (CS‐TFP) edible film using chitosan (CS) and Tremella fuciformis polysaccharide (TFP) as the primary raw materials. The findings revealed significant improvements in the thickness, solubility, opacity, mechanical properties and barrier properties (water vapour and oxygen permeability) of the chitosan film upon the addition of TFP, but water content and hydrophobicity were reduced. Moreover, TFP addition markedly enhanced the antibacterial and antioxidant activities of the chitosan films. Structural analysis of the CS films and CS‐TFP edible films indicated that the formation of hydrogen bonds and high compatibility between CS and TFP. Specifically, TFP increased crystallinity, reduced roughness and improved the compactness of the edible film. This increase in compactness was directly linked to enhanced physical properties, whereas increased crystallinity contributed to better thermal stability. Furthermore, the application of CS‐TFP‐3 edible films in chicken preservation proved that they could significantly delay the deterioration of chicken. Findings in this study suggested that CS‐TFP edible film as a bioactive packaging material showed great potential to preserve chicken meat and extend the shelf life.

Analysis of trapping effects on DC and RF performance in double Π-gate Al0.3Ga0.7N/GaN MOSHEMTs

Abstract This study investigates trap analysis of the DC and RF performance of Al0.3Ga0.7N/GaN Metal-Oxide-Semiconductor high electron mobility transistor (MOSHEMT) with double π-gate technology. The motivation behind double π-gate technology is to evenly distribute the peak electric field and reduce hot electron generation. This gate design helps to lower hot-electron generation across various operating conditions while maintaining device performance, particularly in the lower millimeter-wave frequency range. High dielectric constant HfO2 is used as gate oxide, which helps to lower the gate leakage current. Near the conduction band (CB), the electron quasi-fermi level of 30 meV is achieved. The practical application of HfO2 in AlGaN/GaN HEMTs is limited by its high oxygen permeability, brittleness, and reactivity with moisture and CO2, which can cause mechanical stress and form hafnium carbonate, adversely affecting device performance. Future designs of the double-π gate structure could enhance electrostatic control, reduce short-channel effects, and improve high-frequency performance by scaling down gate dimensions and using high-k or novel dielectric materials. Additionally, optimization for mm-wave and THz applications would help to maintain electron mobility and minimize parasitic capacitance and resistance.

Anion-Doped Perovskite Oxygen-Permeable Membranes Fabricated via an Improved One-Step Thermal Processing Approach.

Anion-doped perovskite membranes with a hollow fiber geometry have excellent oxygen separation performance. However, during the fabrication process of hollow fiber membranes, soaking the precursor in deionized water leads to elemental dissolution, especially anion dissolution. To prevent metal and anion element dissolution, an improved one-step thermal processing approach was proposed in which saturated solutions were used as internal and external coagulation baths, effectively controlling the stoichiometric ratio. Compared with using deionized water as internal and external coagulation baths, using a fluorine-containing saturated solution increased the oxygen flux of the membrane by 21% at 900 °C. The oxygen permeability of the fluorine-doped oxide membrane reached 6 mL cm-2 min-1 at 900 °C, with an oxygen flux exceeding 1 mL cm-2 min-1 at 700 °C, meeting commercial oxygen separation membrane standards. Anion doping and stability enhancement strategies could further advance the development and practical use of oxygen separation membranes.

Sustainable Gelatin‐Based Nanocomposite Packaging Films with Enhanced Physical Properties and Inherent Recyclability

AbstractGelatin‐based composite films with enhanced physical and barrier performance are attractive for food packaging applications due to their potential to address critical challenges in the food packaging industry. This study presents gelatin‐based nanocomposite films reinforced with Ti3C2Tx MXene, developed through solution casting and optimized for food packaging applications. Fourier transform infrared (FTIR) spectroscopy and X‐ray diffraction (XRD) confirm that MXene nanoplatelets interacted with gelatin through the formation of hydrogen bonds. A homogeneous distribution of MXene in the gelatin matrix is observed using scanning electron microscopy (SEM). The in‐plane alignment of MXene is observed by SEM and is quantitatively demonstrated by polarized Raman spectroscopy. The Young's modulus and tensile strength of the films increased from 1.17 to 1.6 GPa and from 39.2 to 48.4 MPa, respectively, with 0.75 wt.% MXene, while the inclusion of MXene nanoplatelets proves highly effective at blocking UV light transmission. The water and oxygen permeability of the films are considerably reduced while composites display a hydrophobic behavior. Quite importantly, the produced films exhibit outstanding recyclability making them a compelling alternative to traditional packaging materials and addressing environmental concerns in the packaging industry.

Antibacterial activity of polyethylene film by hyperthermal hydrogen induced cross-linking with chitosan quaternary ammonium salt

In this study, hyperthermal hydrogen-induced cross-linking (HHIC) technology was applied to construct a dense cross-linking layer of antibacterial chitosan quaternary ammonium salt (HTCC) to PE surface through the selective cleavage of CH bonds and subsequent cross-linking of the resulting carbon radicals. Before HHIC treatment, UV-Ozone was used to activate PE surface to facilitate HTCC adsorption. FT-IR and XPS analyses proved the successful cross-linking between PE and HTCC. From AFM analysis, the prepared PE cross-linked HTCC film (PE-c-HTCC) showed the rougher surface with average roughness (Ra) of 9.16 nm. The water vapor permeability (WVP) and oxygen permeability (OP) values of the film were decreased by about 83 % and 97 %, respectively. Additionally, the film exhibited strong antibacterial properties against E. coli and S. aureus. In terms of these properties, the shelf life of fresh beef could be extended for 2 days after packing with the PE-c-HTCC film.

Thermal Shock Damage and Failure Mechanism of 2D Laminated SiC/SiC with Barium‐Strontium Aluminosilicate‐Based Environmental Barrier Coating

Thermal shock damage is a key issue for the stable service of SiC/SiC with environmental barrier coating (EBC) in aero‐engines. The thermal shock damage behavior of SiC/SiC with barium‐strontium aluminosilicate (BSAS)‐based EBC in an air atmosphere quenched by air and water media between RT and 1200 °C is systematically investigated. After 600 thermal shock cycles, cracks form in the EBC due to a sharp increase in the internal thermal stresses, and a SiO2 TGO layer is formed on the Si bonding coat. Based on the TGO thickness, damage within BSAS/mullite coatings is quantified by the oxygen permeability (2.541 × 10−11 mol·(atm cm s)−1), which is increased by 2.5 times compared to static oxidation. Despite cracking damage occurring in the SiC matrix of SiC/SiC substrates, the load‐bearing capability of SiC fibers is improved due to the modulus matching of the fiber/matrix. Oxidation damage is dominated the degradation of the performance of SiC/SiC substrates, whose flexural strength is decreased by 15% after 600 cycles. In the thermal shock test quenched by water media, the strength retention of SiC/SiC‐EBC is below 60%, and an increase in internal defects and even delamination of the SiC/SiC substrate are the main reasons for the thermal shock failure of SiC/SiC‐EBC.

Preparation and characteristics of sodium caseinate/zein composite coating and its application effect on inhibiting the rancidity of peanut chunks

Sodium caseinate (CN) and zein were used as raw materials to prepare a composite coating applied in air system with mechanical properties, and water vapor and oxygen permeability as evaluation index. Results showed the most suitable conditions were the mass ratio of CN to zein at 0.25: 1, 60% (v/v) aqueous ethanol, polyethylene glycol (0.3 g/g) as the plasticizer, and citric acid (2.5%, w/v) as the crosslinker, and curing temperature at 50 ˚C. Under these conditions, the tensile strength of composite coating was 6.671 MPa, and the elongation at break was 97.596%. The water vapor permeability was 14.236 g·mm/(m2·d·kPa), and the growth rate of peroxide value of tung oils sealed by the composite coating was 71.300%. Results from Fourier transform infrared spectroscopy, atomic force microscopy, scanning electron microscopy, and differential scanning calorimetry revealed that CN and zein were effectively crosslinked by citric acid with improved compatibility and smoother surface of the resulting coating. Results from the accelerated oxidation experiment showed that coating reduced the peroxide value and p-anisidine value of peanut chunks from 1.02 g/100 g and 6.59 to 0.62 g/100 g and 2.24, respectively, indicating that the composite coating prepared effectively inhibited the oxidative rancidity of peanut chunks.

Active polyvinyl alcohol films with enhanced strength, antioxidant and antibacterial properties by incorporating nanocellulose and tannin

There is an increasing demand of food packaging materials from sustainable bio- polymers. In this study, tannin-cellulose nanocrystal (TCNCs) fillers were first prepared using dialdehyde cellulose nanocrystal (DACNCs) and tannin through the nucleophilic addition reaction, and then added to PVA matrix as reinforcement fillers to fabricate active food packaging films. FT-IR analysis confirmed the successful reaction between PVA and TCNCs. The incorporation of TCNCs imparted high antibacterial, UV blocking and antioxidant capabilities to the composite films, maximumly achieving a 75 % DPPH free radical scavenging rate while blocking all UV rays. The addition of TCNCs resulted in an increase in water contact angle, alongside decreases in swelling ratio and solubility, indicating the enhanced water resistance. The composite films exhibited a 66.7 % decrease in oxygen permeability (OP) compared to the PVA film, with a slight increase observed in water vapor permeability (WVP). The tensile strength increased from 49.65 MPa to 74.17 MPa by adding 15 % of TCNCs due to the chemical crosslinking between PVA and TCNCs. Wrapping cherry tomatoes with these films prolonged the postharvest life compared to using polyethylene (PE) and pure PVA films. Films derived from sustainable biopolymers show great potential for use in fresh produce packaging.

The amyloid fibril-stabilized Pickering emulsion significantly enhances the mechanical and barrier properties of Konjac Glucomannan active films for cherry preservation.

Konjac glucomannan (KGM), a natural polymer, is an excellent candidate for use in food packaging due to its desirable film-forming characteristics. However, the limited barrier, antioxidant, and antimicrobial properties of pure KGM films restrict their practical applications. To reinforce the barrier and functional properties of KGM-based films, tea tree oil (TTO) Pickering emulsions stabilized by chitosan-modified soy protein derivative-amyloid fibril (AFS) were prepared and incorporated into KGM matrices. The effects of these Pickering emulsions on the structural and functional properties of KGM films were systematically investigated. The results indicated a favorable compatibility between Pickering emulsions and KGM. The strong interactions among KGM, AFS, and TTO lead to a denser and more compact film structure, improving barrier properties. Specifically, the water vapor and oxygen permeability values of the Pickering emulsion films (group E4C1) were reduced to 0.326 g·mm/(m2·day·KPa) and 4.63 g/m·s·Kpa, respectively. The tensile strength and elongation at the break of the film were increased respectively to 35.02 MPa and 71.8 %. The incorporation of TTO markedly enhanced water resistance, with the total antioxidant capacity of group E5C1 being 9.92 times greater than that of pure KGM films, as well as improving the antimicrobial activity of the KGM-based films. Furthermore, the emulsion film demonstrated effective preservation of cherries, extending their shelf life by approximately 10 days. In conclusion, this study successfully developed a film with enhanced barrier properties and antimicrobial activity, presenting promising applications in food preservation and packaging.

Low friction hydrogel with diclofenac eluting ability for dry eye therapeutic contact lenses.

When placed in the eye, contact lenses (CLs) disturb the tear fluid and affect the natural tribological behaviour of the eye. The disruption in the contact mechanics between the ocular tissues can increase frictional shear stress and ocular dryness, causing discomfort. Ultimately, continuous CLs wear can trigger inflammation which is particularly critical for people suffering from dry eye. In this work, a double strategy was followed to obtain therapeutic daily disposable CLs for dry eye: a hydroxyethyl methacrylate (HEMA) based hydrogel was coated with two natural polysaccharides, chitosan (CHI) and hyaluronic acid (HA) and posteriorly loaded with an anti-inflammatory drug (diclofenac, DCF). Material sterilisation was carried out by high hydrostatic pressure (HHP) combined with moderate temperature. The friction coefficient (μ) was determined in the presence of different tear biomolecules (cholesterol, lysozyme and albumin) using a nanotribometer. Drug release experiments were performed in static and in hydrodynamic conditions. The material was extensively characterised, regarding surface morphology/topography, optical properties, water content and swelling behaviour, wettability, ionic and oxygen permeability and mechanical properties. It was found that the coating did not impair the physico-chemical properties relevant for the material's application in CLs. Besides, it also ensured a sustained release of DCF for 24 h in tests performed in hydrodynamic conditions that simulate those found in the eye, increasing significantly the amount of drug released. It reduced friction, improving the lubrication ability of the hydrogel, and presented antibacterial properties against S. aureus, P. aeruginosa and B. Cereus. The coated samples did not reveal any signs of cytotoxicity or potential eye irritation. Overall, the coating of the hydrogel may be useful to produce daily CLs able to alleviate dry eye symptoms and the discomfort of CLs wearers.

Experimental Characterization of Biodegradable Films Based on Modified Starch and Chitosan

Gas transport and physico-mechanical properties of synthesized films based on modified starch and chitosan have been studied. The values of the permeability coefficients of pure gases included in the air for films based on modified chitosan and a copolymer based on modified starch and chitosan at a temperature of 23°C were determined. The oxygen permeability coefficient of the synthesized copolymer was compared with other polymers. A copolymer based on modified starch and chitosan was found to have medium oxygen barrier properties. The biodegradability of the samples under the action of the micromycete Aspergillus niger was studied by analyzing the degradation products by chromatography-mass spectrometry. The total biodegradation time of the samples was 4 weeks. These films are promising for use as packaging material.

Immobilization of Erythrosine Dye in Polysiloxane to Fabricate a Cost-effective Renewable Antibiotic Film through Visible Light-induced Singlet Oxygen Generation

The advanced oxidation process (AOP) is the most effective strategy to remove volatile organic compounds that are considered to be one of the main pollutants adversely affecting the environment and human health. While metal-based semiconductors are widely considered as promising photocatalysts to remove pollutants through AOP systems, their low light absorption efficiency and poor processibility remain major issues to be utilized for a sustainable AOP system with low energy consumption. However, the organic dye, erythrosine, which can generate singlet oxygens by absorbing visible light, is considered an excellent substitute for metal-based photocatalysts for cheap renewable AOP systems. Accordingly, we here demonstrate a new hybrid membrane, wherein erythrosine molecules are embedded into films of polydimethylsiloxane. The polymeric networks therefore play an important role in enhancing the thermal stability and light absorption efficiency of dye molecules upon hybridization. In addition, the foamed structures of films to enhance their porosity and oxygen permeability are introduced via the fast evaporation of ethanol. As a result, the photocatalytic performance of dyes is significantly reinforced as the porosity of the membrane increases, which is proven by analyzing the degradation efficiency of 1,3–diphenylisobenzofuran with the presence of foamed and hybridized films. The photocatalytic ability of the formed hybrid films was well regenerated in three repeated recycles. Moreover, an optical parametric oscillator (OPO) laser system was used to successfully demonstrate that the singlet oxygen generated from the optimized hybrid film was well diffused into the surface of polymer matrix. Accordingly, the film could effectively sterilize S. aureus and E. coli in an aqueous solution. Therefore, this study suggests that the hybridization of polymer and dye without chemical modification can be an effective strategy to fabricate cheap and reusable porous membranes for a practical environment purification system.

Fabrication of corn starch-based composite films functionalized by Rosa roxburghii Tratt fruit pomace via extrusion compression molding for active food packaging

In this study, various levels (0 %–30 % w/w, based on corn starch) of Rosa roxburghii Tratt fruit pomace (RRTP) were used as antioxidant fillers to develop corn starch (CS)-based bioactive films via the extrusion compression molding technique. The results showed that incorporating RRTP into CS could remarkably improve the barrier, mechanical and antioxidant properties of the films compared to pure CS film. In particular, the composite film containing 30 % RRTP had the lowest water vapor permeability and oxygen permeability of 2.94 × 10−10 g·m·m−2·s−1·Pa−1 and 0.87 × 10−14 kg·m·m−2·s−1·Pa−1, respectively, together with the highest tensile strength of 3.41 MPa and the strongest DPPH scavenging activity of 88.59 %. LCMS analysis confirmed that RRTP contained many phenolic compounds, which conferred high antioxidant activity to the composite films. Additionally, FTIR analyses demonstrated the formation of hydrogen bonds between CS and RRTP, along with good compatibility as confirmed by XRD and SEM. More importantly, the mushrooms packaged in the CS/30%RRTP film maintained optimal appearance and freshness after 12 days at 4 °C, demonstrating the promising role as antioxidant active packaging for food, following new trends for functional packaging.

Enhancing oxygen‐blocking properties of HfB2‐MoSi2‐SiC coating by CeO2 modification

AbstractTo alleviate the destructive alteration of the glass layer surface caused by gas evolution during the oxygen‐blocking process of the HfB2‐MoSi2‐SiC coating, CeO2 was incorporated to modify HfB2‐MoSi2‐SiC coating, and the anti‐oxidation mechanism at 1700°C in air was investigated. Compared with the unmodified HfB2‐MoSi2‐SiC coating, the addition of the refractory CeO2 to the Hf‐B‐Si‐O system leads to the formation of a stable Hf‐Ce‐B‐Si‐O complex phase glass, which substantially enhances the viscosity, stability, and self‐healing sealing properties of the glass layer. The introduction of 0.75 vol.% CeO2 significantly lowers the oxidative activity of the HfB2‐MoSi2‐SiC coating, boosting its average protective efficiency to 99.96% and reducing the maximal oxygen permeability by 43.48%, thus exhibiting superior oxygen‐blocking performance. However, excessive addition of CeO2 leads to an overabundance of oxygen release through its distinctive oxygen vacancy mechanism, which accelerates the formation of Hf‐oxides, resulting in excessive viscosity on the coating surface and leaving oxidation defects unrepaired.

Exploration of modified Polymers of Intrinsic Microporosity (PIM) for extracorporeal membrane oxygenator (ECMO)

Extracorporeal Membrane Oxygenation (ECMO) is the most important supporting therapy to rescue patients with respiratory distress syndrome (ARDS), for which the membrane oxygenator offers a place for CO2 and O2 exchange. Although Poly (4-methyl-1-pentene) (PMP) has been extensively used as ECMO material, the problems of protein adsorption fouling and the need for anticoagulation remain challenging for clinical applications. Additionally, the challenges associated with the functional modification of PMP material underscore the importance of finding a new material with excellent gas permeability and blood compatibility. On the other hand, Polymers of Intrinsic Microporosity (PIM) has been extensively studied in the field of gas separation due to their unique twisted helical structure and high free volume. However, its hydrophobic nature also raises concerns about its anti-fouling ability and hemocompatibility, which restricts the exploration of PIM in ECMO applications. Herein, we modify the PIM-1 membrane and study the hemocompatibility of PIM-1, carboxylated-PIM-1, and amidoxime-functionalized-PIM-1, and explore their gas permeability by molecular dynamics simulation and experimental verification. The modified PIM membranes exhibit remarkable comprehensive performance, including effective anti-protein adhesion and hemocompatibility, high oxygen permeability, and CO2 removal rate. Blood oxygenation tests also reveal that the modified membranes prepared in this work fully meet practical requirements, exhibiting great application potential.

Characterization of biodegradable films based on carboxymethyl cellulose and citrus pectin films enriched with bee bread oil and thyme oil

Films based on polysaccharides (e.g., cellulose esters, pectin) are often utilized as bio-packaging for food products. In this study, films were developed by casting method using carboxymethyl cellulose (CMC), pectin (P), and glycerol incorporated with two essential oils (EOs), bee bread oil (BBO) and thyme oil (TO) in different concentrations (1, 2, and 3%). The formulated films were described in terms of physicochemical properties, as well as through FT-IR spectroscopy, morphological, and thermogravimetric analysis, and with a focus on biodegradation degree. The addition of BBO to CMC films enhanced mechanical properties (77.22–81.96 MPa for tensile strength and 380.5–629.5 MPa for Young's modulus) and reduced barrier characteristics (0.46–0.74 g × mm/kPa × h × m2 and 0.69–0.84 cc × mm/m2 × atm × day for water vapor and oxygen permeabilities, respectively). The EOs decreased the films' opacity and increased their transparency. Considerably, films incorporating 2% and 3% of BBO and TO were completely degraded after 20 days of burial. Furthermore, principal functional groups and interaction between polymers and EOs were observed by FT-IR spectroscopy and morphological analysis of films.

Cellulose nanofibrils-based packaging films synergistically reinforced by lignin and tea polyphenols for strawberry preservation

Developing biomass-based food packaging materials could alleviate resource scarcity and environmental pollution. This study successfully fabricated cellulose nanofibrils-based packaging films synergistically reinforced by lignin and tea polyphenols for fruit preservation. Thanks to the abundant carboxyl and hydroxyl groups in modified lignin and tea polyphenol, the composite film delivered the highest tensile strength and Young’s modulus of 230.7 MPa and 11.9 GPa, respectively. The water vapor permeability (WVP) and oxygen permeability (OP) of composite film were as low as 2.53 × 10−11 g m−1 s−1 Pa−1 and 1.69 × 10−16 cm m−2 s−1 Pa−1, respectively, demonstrating excellent barrier performance. Furthermore, the composite film possessed remarkable antibacterial (100 % antibacterial activity against two types of bacteria), antioxidant (DPPH free radical scavenging activity of 90 %), and UV shielding properties (impressive UV shielding rate of 99.0 %). Strawberry preservation experiments showed that these composite films could significantly extend shelf life, owing to the excellent barrier and antimicrobial properties. Our research indicated that these composite films could be promising food packaging material compared with traditional plastic and showed great application potential in fruit preservation.

Improving the antibacterial properties of polyethylene food packaging films with Ajwain essential oil adsorbed on chitosan particles

The aim of this research is to develop a composite antibacterial film for food packaging using low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), polyethylene-graft-maleic anhydride (PE-g-MA), and incorporating chitosan (CS) particles onto which ajwan essential oil (AEO) is adsorbed. The films were characterized using various techniques, including Fourier-transform infrared spectroscopy (FTIR), Gas chromatography/mass spectroscopy (GC-MS), X-ray diffraction (XRD), tensile testing, oxygen transmission rate (OTR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and antibacterial assays. FTIR results confirmed the presence of CS and/or AEO in the films. Mechanical testing indicated a decrease in tensile strength and an increase in elongation at break with the addition of AEO, while CS reduced elongation. In the sample containing only 7.5% chitosan (PE-7.5-0), the oxygen permeability was reduced to 910 cm2/m2·day·bar due to the presence of CS. However, the inclusion of AEO in the sample (PE-0-10) increased the oxygen permeability to 2200 cm2/m2·day·bar, which is higher than that of the control sample (PE-0-0) with an oxygen permeability of 1680 cm2/m2·day·bar. The antibacterial activity results demonstrated a synergistic inhibitory effect of CS and AEO. Data from GC-MS and inhibition zone (IZ) tests indicated that while chitosan alone does not exhibit significant antibacterial activity due to its incorporation in the bulk of the film, its combination with AEO enhances antibacterial efficacy. This enhancement occurs as the oil is adsorbed and protected from evaporation during the film formation process. Overall, the findings from this research suggest that the composite film PE-7.5-10, which possesses suitable mechanical properties and significant antibacterial activity, could be an effective candidate for food packaging applications.

Active packaging films based on the nanoform of chitin, alginate, and layered double hydroxides: characterization, mechanical properties, permeability, and bioactive properties.

Their unique characteristics make plastic films frequently utilised for packaging products. However, this petroleum-derived material has a long history of being linked to environmental contamination and hazardous degradation. Petroleum plastic can be substituted with edible packaging. The objective of this study was to combine sodium alginate with chitin, both in their nanosized form to formulate active packaging films containing different ratios of Zn/Al-layered double hydroxides (LDHs). Subsequently, active packaging films were formulated via a green method with different percentages (0%, 1%, 3%, and 5% w/w) of LDHs. The LDH particles were shaped as rectangular rods with a length of about 60 nm and width of around 20 nm. The films were evaluated for their physicochemical, topological, thermal, mechanical, water vapour, oxygen permeability and antimicrobial properties. Results indicated that active packaging with LDHs (3%) enhanced mechanical properties (tensile strength) by two-fold. Moreover, the addition of LDHs led to decreased permeability properties. Additionally, the antimicrobial study showed that the films with LDHs possessed a broad spectrum of antibacterial and antifungal activities, and the time required for bacterial killing was recorded to be less than 16 hours for films containing 5% LDHs. Thus, the formulated films show potential for use as active packaging.