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In the food packaging industry, the developments of environmental friendly materials are still one of the challenging areas and many studies have been conducted on the improvement of mechanical and barrier properties of polyvinyl alcohol (PVA) by the incorporation of other polymer. The present study deals with the extraction of cellulose and conversion into nanocellulose (NC) from wood waste of Azadirachta indica and incorporation with polyvinyl alchol (PVA) for food packaging application. The prepared NC was characterized by FT-IR, X-ray diffraction (XRD), scanning electron microscopy (SEM), and particle size analyzer. FT-IR spectrum confirmed the removal of lignin and hemicellulose in the sample. The SEM reveals the morphology of NC which is nanometer in size, and from the particle size analyzer, the diameter of the particle was found to be 121 nm by the DLS method. The X-ray diffraction pattern showed the intensity at 2θ = 22.71 with sharp peak, which confirms the NCs are in crystalline form. The characterized NC was impregnated with polyvinyl alcohol (PVA) and the prepared NC-PVA bionanocomposite film was characterized by FT-IR that confirmed the presence of both functional groups in the film. Then, the improved mechanical properties of tensile strength (N/mm2) and elongation at break (%) were found to be 42.18 and 47.48 at 40 mg of NC concentration. The biodegradability of the films was tested in the outer environmental condition and 97% was degraded within 21 days. Hence, CNF-PVA bionanocomposite packaging material can be used for food packaging purpose in near future. [ABSTRACT FROM AUTHOR]

Active biodegradable films prepared from polylactic acid (PLA)/roselle calyx extract (RCE)/Zinc Oxide Nanorod (ZnO-N) were fabricated as natural packaging materials for hazelnuts protection against microbial contamination and lipid oxidation. The PLA active films with ZnO-N (1, 3, and 5% w/w), and roselle calyx extract (0.5 g) were made by the casting solution technique. The fungal, microbial, chemical, and sensory properties of hazelnuts were measured during 9 months of conservation at 4°C. On the 6 and 9th months, moisture content was evaluated as %2.6 and 2.2% in the control sample whereas the moisture content of hazelnuts was measured as 3.6% and 2.9% packaged with PLA/RCE/%5 ZnO-N. At the last of experiments, the peroxide value (PV) was measured as 0.91 meq O2 kg-1 packaged with neat biocompatible films, whereas PV value was detected as 0.65 meq O2 kg-1 in packaged hazelnuts with %5 ZnO-N. Total microbial count ranged between 4.9 cfu g-1 for hazelnuts packaged with neat PLA and 3.7 cfu g-1 for hazelnuts specimens packaged with %5 ZnO-N after 9 months of storage. At 9 months, by increasing the level of ZnO-N from 1% to 5%, the mold count was reduced from 3.64 to 3.01 CFU g-1. The fungal contamination in the neat specimens was 3.95 CFU g-1. Sensory quality indicated that hazelnuts with ZnO-N had a significant impact on flavor and aroma, and the highest quality of sensory evaluation was related to hazelnuts packaged with PLA/5% ZnO-N/RCE. Flavor and aroma indices of hazelnuts packaged with %5 ZnO-N reached 3.5 and 4.5 respectively after 9 months of storage. The obtained findings indicate that biopackaging could be utilized to enhance microbial quality and inhibit oxidation reactions of hazelnuts during cold storage. Our results could be beneficial for introducing attractive characteristics to the biodegradable film packaging for example active film containing anthocyanin/nanofiller and can be applied when selecting a smart packaging for detection of food spoilage.

Egg waste is a major contributor to global food waste, accounting for 15% of discarded food in the United States. Typically, eggs have a shorter shelf life at room temperature and are preserved in refrigeration from production to consumption. However, maintaining constant refrigeration is energy‐intensive and expensive. Here, a bionanocomposite coating has been developed that incorporates each element of eggs – egg white, yolk, and eggshell – to increase the shelf life of fresh eggs without requiring further refrigeration. The quality of eggs has been successfully preserved for up to three weeks at room temperature. The coated eggs maintain the highest grade (AA) and exhibit improved Haugh Unit (HU), Yolk Index (YI), and pH compared to uncoated eggs. The coating reduces weight loss by ≈37% with an increase in HU (≈12.5%) and YI (≈13.9%). Morphological analysis reveals strong adhesion of the coating to the eggshell surface, showcasing promising barrier properties. The coating demonstrates an optimal combination of oxygen permeability (≈12.2 cm3 µm m−2 d−1 kPa−1) and water vapor transmission (≈31.5 g mm m−2 per day) with excellent antimicrobial properties. Overall, this approach of repurposing eggs into a high‐performance coating shows a promising viable alternative to refrigeration and a solution to combat egg waste. [ABSTRACT FROM AUTHOR]

Ni-doped Copper oxide (Ni-CuO) nanoparticles have been synthesized from Arabic Gum. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) polyester was biosynthesized by the microorganism Haloferax mediterranei utilizing date waste as carbon source. The produced Ni-doped copper oxide (Ni-CuO) nanoparticles have been incorporated with different percentages into the PHBV matrix. The produced bionanocomposites were achieved with different percentages of the nanoparticles: 1%, 3%, 5% and 10%, and were referred to as PHBV/Ni-CuO(1,3,5,10%). FTIR, TGA, XRD, SEM and EDX techniques have been used to study and characterize the synthesized bionanocoposites. In addition, the prepared nanocomposites were studied for their efficiency as solid phase adsorbents for Brilliant Green (B.G.) dye from water resources under different conditions. The prepared nanocomposites were found to be very efficient and promising solid phase adsorbent materials to treat water samples for the purpose of dye removal. The percentage of the removed dye increased from 45.6% to 97.7% as the PHBV/Ni-CuO(10%) nanocomposite amount increased from 10 mg to 70 mg per 25 mL of water sample. The dye removal percentage reached an equilibrium in 90 min. Natural water samples from three different sources have been tested against the Ni-CuO/PHBV(3%) nanocomposite as solid adsorbent for the B.G. removal, and the results showed >90% dye removal in all cases under the optimum experimental conditions. [ABSTRACT FROM AUTHOR]

In this study, we delved into cutting-edge strategies for the effective management of wastewater, a critical issue exacerbated by industrial pollution and urban expansion. We introduce the use of carbon-based nanomaterials (CBNs), either alone or functionalized with bacteria, as a novel nanobiotechnological solution for urgent nanobioremediation needs. This technique is notable for its exceptional ability to remove various industrial pollutants, including heavy metals, pesticides, textiles, and dyes, emphasizing the pivotal role of CBNs. The development of bionanocomposites through the integration of CBNs with bacteria represents a significant advancement in enhancing bioremediation efforts. In this study, we assessed the potential health and environmental risks associated with CBN usage while offering an in-depth evaluation of the adsorption mechanisms and factors influencing bioremediation effectiveness. Furthermore, the improved efficiency in treating industrial effluents facilitated by bionanocomposites was investigated, and their alignment with circular economy principles through recyclability is discussed. We aimed to provide, a detailed overview of recent advancements, challenges, and prospects for CBNs and bacterial application in sophisticated wastewater treatment, underscoring their vital importance in promoting the environment. [ABSTRACT FROM AUTHOR]

This paper reports on the biosynthesis, characterization, as well as the bactericide and cytotoxic properties of silver nanoparticles supported on bovine bone powder (Ag-NPs/BBP). The silver nanoparticles were obtained through the bioreduction of AgNO3, using an infusion of Heterotheca inuloides leaves and flowers as a reducing agent and bovine bone powder as a support. The ratio of Ag-NPs/bovine bone powder was set as 1:10. The characterization was performed with SEM–EDS, XRD, UV–Vis, and TEM, which showed the formation of nanoparticles with an average size of 22.6 ± 10.8 nm and a quasi-spherical Ag-NPs morphology supported on the BBP surface. The nanocomposite exhibited a band gap of 2.19 eV. The minimal inhibitory concentration and the minimal bactericidal concentration against S. aureus, E. coli, and S. epidermidis were determined for each strain. In addition, the cytotoxic evaluation of the Ag-NPs/BBP on J774.2 mouse macrophage cells was performed. The Ag-NPs/BBP exhibited a bactericide effect on the strains studied, and the cytotoxicity had a dose-dependent behavior on the cells studied. Therefore, it was found that the ecofriendly synthesized Ag-NPs supported on bovine bone powder resulted in an effective bactericidal system against the strains studied, without significant cytotoxicity. [ABSTRACT FROM AUTHOR]

Cellulose is one of the most widely used and widely available materials on the planet, and it has been used for centuries in a wide range of applications. In this paper, a new source of cellulose delonix regia fruits has been explored for the extraction of cellulose at the micro and nanoscale. Cellulose is isolated from the raw delonix regia fruits by sub-sequential chemical methods such as pulping, bleaching, delignification, and acid hydrolysis. PVA/CMF and PVA/CNF composites are prepared by the solvent casting process with 1, 3, 5, 7, and 9 percentages of filler concentration. Mechanical, thermal, morphological, moisture absorption, and biodegradability properties of pure PVA, PVA/CMF, and PVA/CNF composite at different filler concentrations were evaluated using mechanical testing (tensile, flexural, and impact), TGA-DTG, SEM, moisture absorption test and soil burial test respectively. The SEM results showed that at increased filler content concentrations, signs of agglomeration began to occur, and the overall performance of the resulting composite material degraded due to which filler addition should be limited to less than 7wt%. Tensile, flexural, and impact test results revealed that nano-fillers performed better than micro-fillers, and the best performance is obtained with filler content below 7%. The degradation temperature of composites with filler content improved dramatically, according to TGA and DTG curves, and composites with nano-fillers had greater thermal stability than composites with micro- fillers. The inclusion of filler content reduced the tendency of composite materials to absorb moisture and the resulting composite materials had enough biodegradation rate together with higher lifetime and performance, according to the findings of the biodegradability test and moisture absorption test. [ABSTRACT FROM AUTHOR]

This study evaluated the ability of tea tree essential oil (TT) incorporated into polymer-clay bionanocomposites to in vitro eliminate resistant microorganisms towards applications in antibacterial wound healing. Antimicrobial bionanocomposites were prepared in two steps, namely sonication and melt intercalation, and montmorillonite clay and poly(acid lactic) (PLA) were chosen because they constitute a polymer-clay bionanocomposite to be applied in wound dressing. X-ray diffraction (XRD) results indicated good incorporation of the organic compounds, TT oil, and glycerol (G) (the latter used as a plasticizer) into the clay galleries. Dynamic-mechanical analysis (DMA) results showed a 2–30 % increase in storage modulus and up to 10 °C decrease in glass transition temperature, proving the influence of both TT oil and G on the stress transfer of the reinforcement clay phase. Thermogravitmetric analyses (TGA) revealed TT oil and G addition worsened the thermal stability of the bionanocomposites, which show a mass loss onset decrease up to 90 °C and a clay content between 1.5 and 3 wt%. In vitro antimicrobial activity tests revealed only the combinations of TT oil and G reduced Escherichia coli and Staphylococcus aureus satisfactorily and showed the antimicrobial activity of the bionanocomposites.

Advance nanocomposites, also known as bionanocomposites/biopolymer composites or bionanomaterials, have gained desirable attention in the area of scientific and technological advancement, premised on the need for eco-friendly and sustainable biopolymer-based nanocomposites, unlike the non-biodegradable petroleum-based nanocomposites. Analytical instrumental techniques such as FTIR, SEM-EDX, XRD, DLS, DMA, and TGA have been recounted to be effective in characterizing bionanocomposites in order to determine their properties and envisage their practical applications. Advance nanocomposite has found practical applications in food packaging for preserving and extending the shelf life of food products, in addition to biomedical operation as well as water treatment, sensors, and electronic devices. The contribution impact of bionanocomposite in the field of material science has springed up a desirable outcome in reducing the overdependence of petroleum-based nanocomposites. [ABSTRACT FROM AUTHOR]

This study investigated the characterization, antifungal activity, and biocompatibility of green agar/silver and collagen/silver bionanocomposite films for wound healing and cell growth scaffolds. Silver nanoparticles (AgNPs) are known for their antimicrobial properties, but their toxicity and harsh synthesis limit their applications. To address this, green‐synthesized AgNPs G‐AgNPs were incorporated into agar/collagen suspensions at specific concentrations and three different G‐AgNP‐agar and two different G‐AgNP‐col bionanocomposite films were produced. Nanoparticle homogeneity and film quality were characterized through SEM analysis. Mechanical properties were tested using a uniaxial tensile tester, revealing that the bioplastic control samples exhibited UTS of 3.86 MPa compared to 0.60 MPa for collagen, a 6‐fold improvement. Viable cell metabolic activity derived from MTT assay showed that Col‐4%AgNPs and Bio‐30%AgNPs had a 42.9% and 51.6% increase in net metabolic activity respectively compared to control on day 4. Fluorescence microscopy confirmed enhanced cell adhesion and proliferation in G‐AgNP‐incorporated samples. Antifungal properties were evaluated against Cladosporium spores, able to cause severe diseases when in contact with human skins, following ISO 16869:2008 standards. The demonstrated unique properties and tunability of G‐AgNPs bionanocomposites can be employed in a variety of specialties for wound‐healing applications, to improve rate and quality of healing while reducing the risk of infection. [ABSTRACT FROM AUTHOR]

Studies on bionanocomposite drug carriers are a key area in the field of active substance delivery, introducing innovative approaches to improve drug therapy. Such drug carriers play a crucial role in enhancing the bioavailability of active substances, affecting therapy efficiency and precision. The targeted delivery of drugs to the targeted sites of action and minimization of toxicity to the body is becoming possible through the use of these advanced carriers. Recent research has focused on bionanocomposite structures based on biopolymers, including lipids, polysaccharides, and proteins. This review paper is focused on the description of lipid-containing nanocomposite carriers (including liposomes, lipid emulsions, lipid nanoparticles, solid lipid nanoparticles, and nanostructured lipid carriers), polysaccharide-containing nanocomposite carriers (including alginate and cellulose), and protein-containing nanocomposite carriers (e.g., gelatin and albumin). It was demonstrated in many investigations that such carriers show the ability to load therapeutic substances efficiently and precisely control drug release. They also demonstrated desirable biocompatibility, which is a promising sign for their potential application in drug therapy. The development of bionanocomposite drug carriers indicates a novel approach to improving drug delivery processes, which has the potential to contribute to significant advances in the field of pharmacology, improving therapeutic efficacy while minimizing side effects. [ABSTRACT FROM AUTHOR]

Biosilica, synthesized annually only by diatoms, is almost 1000 times more abundant than industrial silica. Biosilicification occurs at a high rate, although the concentration of silicic acid in natural waters is ~100 μM. It occurs in neutral aqueous solutions, at ambient temperature, and under the control of proteins that determine the formation of hierarchically organized structures. Using diatoms as an example, the fundamental differences between biosilicification and traditional sol–gel technology, which is performed with the addition of acid/alkali, organic solvents and heating, have been identified. The conditions are harsh for the biomaterial, as they cause protein denaturation and cell death. Numerous attempts are being made to bring sol–gel technology closer to biomineralization processes. Biomimetic synthesis must be conducted at physiological pH, room temperature, and without the addition of organic solvents. To date, significant progress has been made in approaching these requirements. The review presents a critical analysis of the approaches proposed to date for the silicification of biomacromolecules and cells, the formation of bionanocomposites with controlled structure, porosity, and functionality determined by the biomaterial. They demonstrated the broad capabilities and prospects of biomimetic methods for creating optical and photonic materials, adsorbents, catalysts and biocatalysts, sensors and biosensors, and biomaterials for biomedicine. [ABSTRACT FROM AUTHOR]

Bionanocomposite is considered an advanced way to bridge the gap between the structural and functional material and achieve the desired properties in the nanocomposite. This present study highlighted the synthesis of fish gelatin-based magnetic nanocomposite (GMNC) using three different concentrations of gelatin (6% w/v, G12% w/v, and 18% w/v) individually, through the in situ coprecipitation method. The effect of gelatin concentration on the structural, functional, magnetic properties, and biocompatibility of the GMNC was studied successfully. This variation reduces the crystallite size from 20.8 to 12.2 nm. GMNC obtained at minimum gelatin concentration (6% w/v) produced well-dispersed sphere-shaped magnetite nanoparticles with an average particle size of 33 nm without aggregation. All three reported superparamagnetic behavior at 293 K. It also noted the highly biocompatible and biodegradable nature of GMNC with a high magnetic response at a low magnetic field. This study reported the perspective of this functionalization method for biomedical applications, as GMNC is a potential carrier material that is easily attached to drug molecules through the free functional residues of gelatin molecules. The present study also performed the in vitro drug release behavior of 5′Fluorouracil-loaded GMNC (GF) at physiological conditions (pH 7.4 and 37 °C). It indicates the prepared GF exhibits a sustained drug-release profile for up to 48 h. Hence, these results strongly supported that the functionalized GMNC would be a potential carrier material for advanced drug delivery applications. [ABSTRACT FROM AUTHOR]

Sodium alginate (SA)/hydroxyapatite (HA)/graphene nanoplatelets (GP) bionanocomposite films that possess good biocompatibility for bone tissue engineering are prepared by a simple solution casting process. The prepared nanocomposite films are analyzed by XRD, SEM, EDAX, and FTIR analyses. XRD confirms the presence of hydroxyapatite and graphene nanoplatelets in the nanocomposite. FTIR spectrum confirms the interaction between the matrix and the fillers. The morphology of the fillers and nanocomposite films are observed through SEM images. The inclusion of GP with different concentrations into the biopolymer film improves the tensile strength. As a result, the loading of 0.5 wt% of graphene and 10 wt% of HA in the SA polymer shows high tensile strength when compared to the pure SA and SA filled with HA. Tensile strength gradually decreases when the loading of graphene is increased to 2.5% and 5% in the bionanocomposite film. The tensile strength of the bionanocomposite film with 10% of hydroxyapatite is increased by 17%, whereas the tensile strength of the bionanocomposite film loaded with 10% of hydroxyapatite and 0.5% graphene is increased by 99%. Biological tests, such as swelling, biodegradation tests, and biomineralization tests, confirm the biocompatibility of the nanocomposite films. [ABSTRACT FROM AUTHOR]

In this study, we delved into cutting-edge strategies for the effective management of wastewater, a critical issue exacerbated by industrial pollution and urban expansion. We introduce the use of carbon-based nanomaterials (CBNs), either alone or functionalized with bacteria, as a novel nanobiotechnological solution for urgent nanobioremediation needs. This technique is notable for its exceptional ability to remove various industrial pollutants, including heavy metals, pesticides, textiles, and dyes, emphasizing the pivotal role of CBNs. The development of bionanocomposites through the integration of CBNs with bacteria represents a significant advancement in enhancing bioremediation efforts. In this study, we assessed the potential health and environmental risks associated with CBN usage while offering an in-depth evaluation of the adsorption mechanisms and factors influencing bioremediation effectiveness. Furthermore, the improved efficiency in treating industrial effluents facilitated by bionanocomposites was investigated, and their alignment with circular economy principles through recyclability is discussed. We aimed to provide, a detailed overview of recent advancements, challenges, and prospects for CBNs and bacterial application in sophisticated wastewater treatment, underscoring their vital importance in promoting the environment.

Innovative bionanocomposite foams based on precipitated Kraft lignin (Lig) and Kraft black liquor (BL) loaded with sepiolite (Sep) were prepared. BL/Sep bionanocomposites were synthesized by emulsion templating and Lig/Sep bionanocomposites were prepared by freeze-drying, resulting in stable and rigid foams. BL/Sep bionanocomposites displayed a closed cell structure, a specific area between 19 and 35 m2/g and macropores of varying sizes. The porosity in this technique is achieved by the mechanical agitation of the emulsion. On the other hand, freeze-dried Lig/Sep bionanocomposites showed open cell morphology with surface areas ranging from 1 to 4 m2/g and uniform macropores due to the ice-templating process. The presence of sepiolite in both types of bionanocomposite foams improved their stiffness, with Young's moduli ranging from 0.21 to 9.6 MPa. The capacity of the foams to adsorb metals, drugs and dyes was evaluated and it was found that the synthesized bionanocomposite foams exhibiting similar adsorption capacities as that reported for lignin. Sepiolite significantly improved the adsorption of Cu(II), Cd(II), acetaminophen (ACT), and methylene blue (MB) in BL/Sep bionanocomposites. Meanwhile, the Lig/Sep bionanocomposites demonstrated superior adsorption capacities for the Cr(VI) anion and aromatic ring compounds, including ACT and MB. In this respect, these lignin-sepiolite foams can be considered as promising materials for the removal of pollutants in aqueous solution.

Hypothesis: In recent years, scientists and researchers have been looking for new and advanced materials for use in various fields, including drug delivery and biotechnology. One of the attractive materials that has been considered in this field is chitosan-based bionanocomposite hydrogel beads. Chitosan-based bionanocomposite hydrogel beads have attracted attention as carriers in drug delivery systems due to their inherent properties such as excellent biocompatibility, high swelling, and high storage capacities.Methods: First graphene quantum dots (GQDs) were prepared by the pyrolysis method, and then their magnetic properties were obtained using iron nanoparticles (MGQD). Next they were coated with chitosan hydrogel (CS-MGQD) and finally loaded with methotrexate (MTX/CS-MGQD). This unique combination of the properties of chitosan hydrogel, the magnetic properties of graphene quantum dots, and the ability to adjust drug release has been able to create an important milestone in the field of drug delivery research and the compatibility of drugs with the biological environment. Through various analyses, including FTIR to analyze the spectra of the functional groups, XRD to identify the crystal structure, and SEM to examine the morphology of the samples, the success of the synthesis and formation of the desired compound was confirmed.Findings: The fabricated CS and CS-MGQD hydrogel beads were loaded with about 84% and 64% MTX, respectively. The results of the swelling behavior and drug release behavior showed that the hydrogel beads experience pH-dependent swelling and release of MTX. In addition, investigating the effect of MGQD concentration on swelling behavior and drug release showed that CS-MGQD has favorable stability and controllable drug release in an acid environment. Also, the Weibull kinetic model was found to be the best-fitting model for the release of MTX from CS-MGQD at pH 5. These findings suggest that the prepared magnetic bionanocomposite hydrogel beads have a good potential for pH-sensitive implantable drug delivery in the treatment of cancerous tissue.

Abstract This study investigated the characterization, antifungal activity, and biocompatibility of green agar/silver and collagen/silver bionanocomposite films for wound healing and cell growth scaffolds. Silver nanoparticles (AgNPs) are known for their antimicrobial properties, but their toxicity and harsh synthesis limit their applications. To address this, green‐synthesized AgNPs G‐AgNPs were incorporated into agar/collagen suspensions at specific concentrations and three different G‐AgNP‐agar and two different G‐AgNP‐col bionanocomposite films were produced. Nanoparticle homogeneity and film quality were characterized through SEM analysis. Mechanical properties were tested using a uniaxial tensile tester, revealing that the bioplastic control samples exhibited UTS of 3.86 MPa compared to 0.60 MPa for collagen, a 6‐fold improvement. Viable cell metabolic activity derived from MTT assay showed that Col‐4%AgNPs and Bio‐30%AgNPs had a 42.9% and 51.6% increase in net metabolic activity respectively compared to control on day 4. Fluorescence microscopy confirmed enhanced cell adhesion and proliferation in G‐AgNP‐incorporated samples. Antifungal properties were evaluated against Cladosporium spores, able to cause severe diseases when in contact with human skins, following ISO 16869:2008 standards. The demonstrated unique properties and tunability of G‐AgNPs bionanocomposites can be employed in a variety of specialties for wound‐healing applications, to improve rate and quality of healing while reducing the risk of infection.

A novel and efficient bionanocomposite was synthesized by incorporating SnO into chitosan (Ch) and a room-temperature ionic liquid (RTIL). The bionanocomposite was synthesized in benzoyl pyridinium chloride [BzPy]Cl to maintain the unique properties of SnO, chitosan, and the ionic liquid. Adsorption and photodegradation processes were applied to evaluate the bionanocomposite for removing azo and anthraquinone dyes and textile wastewater. SnO/[BzPy]Cl and SnO/[BzPy]Cl/Ch samples were prepared and characterized using various techniques, including FT-IR, SEM, XRD, EDAX, XPS, DSC, TGA, nitrogen adsorption/desorption isotherm, and DRS analysis. SEM analysis revealed a hierarchical roughened rose flower-like morphology for the biocomposite. The band gap energies of SnO/[BzPy]Cl and SnO/[BzPy]Cl/chitosan were found to be 3.9 and 3.3 eV, respectively, indicating a reduction in the band gap energy with the introduction of [BzPy]Cl and chitosan. SnO/[BzPy]Cl/Ch showed high removal rates (92–95 %) for Fast Red, Blue 15, Red 120, Blue 94, Yellow 160, and Acid Orange 7 dyes. The adsorption kinetics followed a pseudo-second-order model.In addition, the effect of different photodegradation parameters such as solution pH, dye concentrations, contact time, and amount of photocatalyst, was studied. Given the optimal results obtained in removing azo and anthraquinone dyes, the SnO/[BzPy]Cl/Ch nanocomposite was used as an efficient nanocomposite for removing dyes from textile wastewater. The highest removal efficiency was found to be 95.8 %, obtained under ultraviolet and visible light. Furthermore, BOD and COD reduction analysis showed significant reductions, indicating the excellent performance of the photocatalyst.

New hybrid metal organic framework based polymer nanocomposite (ZIF-8/NC-PU) and interpenetrating polymer gel nanocomposites (NC-PU) were prepared for the adsorption of cationic (Rh-B) and anionic (IC) dyes from aqueous solution. The characterisation of the ZIF-8 based composites and gel composites is carried out using FT-IR and SEM analysis to investigate the chemical composition and morphology of the sample. Moringa oleifera seed pod based nanocellulose (5 wt%) is used as the filler in NC-PU gel composites and ZIF-8/NC-PU MOF composites. The optimal level of the most significant identified variables affecting the adsorption process were determined by the response surface methodology (RSM) using Plackett–Burman and Box–Behnken design. Adsorption capacity increased with the increase in dosage of the adsorbent, pH and initial dye concentration. Plackett–Burman was performed for the experiments involving the dyes Rh-B and Indigo carmine dyes. It gave 12 experiments in each trials and resulted in 3 significant parameters. Box–Behnken was further used to determine the optimum parameters for the adsorption keeping PU weight percentage as 3. The percentage uptake predicted by the model is in good agreement with the experimental values. The findings assume that the adsorbents could be used effectively as highly efficient adsorbents for the removal of multiple dyes from wastewater. [ABSTRACT FROM AUTHOR]

The main objective of this work was to prepare biodegradable packaging film based on the organic base polymer for the replacement of petroleum based plastic films. Therefore, the present investigation is conducted to characterize gluten-polyvinyl alcohol (PVA) based bionanocomposite films containing two concentrations of montmorillonite (MMT) as 2% and 4% and chitosan as 1.5% and 2.5% for their functional properties, barrier properties, morphological, biodegradable, and microbial properties. Results indicated that films prepared with 2% MMT and 2.5% chitosan has represented high transparency with low opacity value (2.47 AUmm−1). Further, tensile strength (TS) and water vapour transmission rate (WVTR) of the films were found higher in the same film as 58.94 MPa and 0.06 g/h cm2, respectively. However, uniform and smooth surface morphology was obtained due to the interaction between MMT (2%) and matrix. While, increasing the concentration of MMT cause cavities on the surface of films and reduced TS of the films. The composite films degraded under soil within 55 days as noticeable achievement in research area. Moreover, intercalation between gluten-PVA matrix and MMT resulted in appreciable modifications of their structures, which were supported by X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. The nanoclay exfoliates for better interaction with other components and large surface area make their functionality more intense in comparison to macromolecules. Therefore, the synergistic effect of MMT and chitosan has enhanced functional, mechanical and barrier characteristics, can be an alternative approach for the replacement of hazardous non-biodegradable plastic packaging material being used for industrial applications. [ABSTRACT FROM AUTHOR]

One of the activities most representative of the agricultural sector in Colombia is the production of biodegradable fique fiber. The efficiency of the defiberization process of the fique leaves is very low since a mere 4% of the total weight of the leaf (cabuya) is used and marketed. The remaining 96%, composed of fique juice and bagasse, is considered to be waste and discarded, impacting the environment. The aim of this work was to study fique bagasse as a source of cellulose nanoparticles (CNCs). CNCs were obtained by acid hydrolysis and added at 10% to films made from cassava thermoplastic starch (TPS) by the casting method. Structural changes in the CNCs, TPS, and their mixtures were characterized by FTIR-ATR and their morphology and particle size by SEM and TEM microscopy, respectively. Thermal properties were analyzed using DSC and TGA, along with their effect on mechanical properties. Changes in the FTIR spectra indicated that the chemical method adequately removed hemicellulose and lignin from the fiber surface of fique bagasse. The CNCs showed a diameter and length of 7.5 ± 3.9 and 52.7 ± 18.1 nm, respectively, and TPS 10% CNC obtained an increase in mechanical strength of 116%. The obtainment of CNCs from lignocellulosic materials can thus be viewed as a favorable option for the subsequent reinforcement of a polymeric matrix. [ABSTRACT FROM AUTHOR]

The current assignment describes on the integration of chitosan nanoparticles in the polymeric matrix of polyaniline (PANI)—polyvinyl alcohol (PVA) resulted in the successful fabrication of a novel bionanocomposite. The cost-effective and easy ionic gelation procedure was used to synthesize chitosan nanoparticles (CNPs) and transmission electron microscopy analysis presented the spherical shape with a nano-regimen below 47 nm of CNPs. The Fourier transform infrared spectroscopy results highlighted the distinctive functional groups and chemical interactions associated with chitosan nanoparticles and the polyaniline–polyvinyl alcohol matrix. The integration of chitosan nanoparticles had an effect on the amorphous character of the synthesized bionanocomposite, according to X-ray diffraction studies. The surface morphology was revealed by field emissions scanning electron microscopy pictures, and thermo-gravimetric analysis revealed that the inclusion of chitosan nanoparticles improved thermal stability. Cyclic voltammetry is used to determine the electroactivity of a synthesized material. The antibacterial activity of bionanocomposite was tested against Gram-positive bacteria Enterococcus faecalis and Staphylococcus aureus, as well as Gram-negative bacteria salmonella typhi and Escherichia coli. The highest antibacterial activity of all the bacterial strains was at 13 mm, 10.9 mm, 15 mm, and 17 mm, respectively. The synergistic effect of PANI-PVA-CNPs, as evidenced by its mechanical properties, swelling ratio, and percentage of porosity results, supported that the addition of CNPs to PANI-PVA enhanced the values suitable for the regeneration of skin tissues. The in vitro hemolytic study demonstrated the hemocompatibility value was less than 2%, implying that the bionanocomposite has the potential to be used as an efficient material in skin tissue engineering applications. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA) has shown very promising results in hard tissue engineering because of its similarity to bone and hence the capability to promote osteogenic differentiation. While the bioactivity of HA is uncontested, there are still uncertainties about the most suitable hydroxyapatite particle shapes and sizes for textile scaffolds. This study investigates the influence of the shape and size of HA particles on as spun fibers of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and HA, their mechanical and thermal properties as well as their influence on the fiber degradation in simulated blood matrix and their capability to mineralize in simulated body fluid. The key findings were that the different HA particles’ size does not affect the melting temperature and still maintains a thermal stability suitable for fiber production. Tensile testing revealed decreased mechanical properties for PHBV/HA as spun fibers, independently of the particle morphology. However, HA particles with 30 nm in width and 100 nm in length at 1 wt% HA loading achieved the highest tenacity and elongation at break amongst all composite fibers with HA. Besides, the Ca/P ratio of their mineralization in simulated body fluid is the closest to the one of mineralized human bone, indicating the most promising bioactivity results of all HA particles studied.

Haloferax mediterranei archaea has been utilized to biosynthesize Poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) polyester from date waste as carbon source. The produced biopolymer has been composited with different percentages (1 %, 3 %, 5 % and 10 %) of a hybrid filler based on 1 : 1 carboxylated multi‐walled carbon nanotubes (CMWCNTs) and graphene nanoplates (GNPts). The synthesized bionanocomposites PHBV/(CMWCNTs‐GNPts)(1,3,5,10%) have been characterized by FTIR, TGA, XRD, SEM and EDX. In addition, they were studied for their antibacterial properties against gram negative and gram positive strains of M. Luteus, S. Aureus, P. Aerugensa and E. Coli, and the results showed excellent antibacterial effect especially against gram negative strains of P. Aerugensa and E. Coli, showing inhibition zones of 52 % and 81 %, respectively, compared to chloramphenicol control that is used. Also, antifungal activities were investigated against G. Candidum and C. Albicans and showed that the produced bionanocomposites had inhibition zones of 32 % and 73 %, respectively, compared to the antifungal drug clotrimazole which was used as control. [ABSTRACT FROM AUTHOR]

In the present research, we aimed to develop a simple and green approach to producing a very versatile Ag@AgCl/Fe3O4@kaolinite bionanocomposite with the aid of the aqueous extract of Melissa officinalis. In fact, the Ag@AgCl sample, biosynthesized using the extract, was upgraded with imprinting on kaolinite to produce the Ag@AgCl/kaolinite bionanocomposite. Likewise, we synthesized the four-component Ag@AgCl/Fe3O4@kaolinite for promoting the properties and applications of the as-made nanocomposites. The products were characterized using various techniques such as UV–Vis, FT-IR, XRD, FE-SEM, EDX and XPS. Moreover, they were utilized not only as the efficient heterogeneous catalysts for the reduction of para-nitrophenol to para-aminophenol, but also as the useful biosensors for the detection of Hg2+ in the aqueous media. The resulting heterogeneous catalysts, thus, featured valuable advantages like easier work-up, better stability, and greater separation ability using an external magnet. [ABSTRACT FROM AUTHOR]

This work identifies Pepper (Capsicum annuum L) stems residue as a new potential source for producing high-quality cellulose nanocrystals (CNCs), making a significant contribution to the field of natural waste material utilization and sustainability. It also compares the properties of CNCs produced using two different acids, phosphoric acid and sulfuric acid (CNCPs and CNCSs), providing new insights into their properties and polymer reinforcing ability. Hence, the as-isolated CNCPs (D = 43 ± 15.11 nm, CrI = 84.78%) and CNCSs (D = 31 ± 8.80 nm, CrI = 85.41%) were separately dispersed in starch at different weight loadings, and their reinforcing effects on the chemical, morphological, thermal, transparency and mechanical properties of the resulting starch-based biocomposite films were discussed. Globally, the incorporation of CNCs into starch biopolymer improved all these properties due to their rather similar polysaccharide structure and thus good interfacial interaction. However, the capacity of phosphoric acid to produce char made CNCPs effective flame retardants, thus providing bionanocomposite films with better thermal stability than CNCSs ones. In counterpart, the negative charge provided by the residual sulfate group (SO42−) in CNCSs, coupled with their high aspect ratio, high surface areas and crystallinity, significantly improves the dispersibility of CNCSs in the ST matrix compared to the phosphoric acid-derived CNCs. Hence, adding up to 5 wt% CNCSs improved the film's transparency by 25%, stiffness by 196%, and ductility by 169%, compared to 11%, 164% and 114%, respectively, for CNCPs. Here, this work offers valuable insights into the utilization of pepper stems residue and the type of acid for CNCs production with outstanding characteristics. [ABSTRACT FROM AUTHOR]

This paper builds on the context and recent progress on the control, reproducibility, and limitations of using graphene and graphene-related materials (GRMs) in biomedical applications. The review describes the human hazard assessment of GRMs in in vitro and in vivo studies, highlights the composition–structure–activity relationships that cause toxicity for these substances, and identifies the key parameters that determine the activation of their biological effects. GRMs are designed to offer the advantage of facilitating unique biomedical applications that impact different techniques in medicine, especially in neuroscience. Due to the increasing utilization of GRMs, there is a need to comprehensively assess the potential impact of these materials on human health. Various outcomes associated with GRMs, including biocompatibility, biodegradability, beneficial effects on cell proliferation, differentiation rates, apoptosis, necrosis, autophagy, oxidative stress, physical destruction, DNA damage, and inflammatory responses, have led to an increasing interest in these regenerative nanostructured materials. Considering the existence of graphene-related nanomaterials with different physicochemical properties, the materials are expected to exhibit unique modes of interactions with biomolecules, cells, and tissues depending on their size, chemical composition, and hydrophil-to-hydrophobe ratio. Understanding such interactions is crucial from two perspectives, namely, from the perspectives of their toxicity and biological uses. The main aim of this study is to assess and tune the diverse properties that must be considered when planning biomedical applications. These properties include flexibility, transparency, surface chemistry (hydrophil–hydrophobe ratio), thermoelectrical conductibility, loading and release capacity, and biocompatibility. [ABSTRACT FROM AUTHOR]

The current study focuses on microwave‐assisted zinc oxide quantum dots synthesis (ZnO‐QDs) from zinc oxide bionanocomposite (ZnO‐BC) preparation. The novelty lies in the preparation of ZnO‐QDs, since the natural elements present in ZnO‐BC itself acted as a surface penetration enhancer without using any chemical agent. Under ultraviolet (UV) light ZnO‐QDs emitted a blue glow, confirming the fluorescence property. Using Box–Behnken design, the experimental factors of ZnO‐QDs were optimized, yielding a positive response of 350 nm absorbance and these results also matched with the UV‐visible spectroscopy characterization studies of ZnO‐QDs. Using Escherichia coli, the antibacterial activity of ZnO‐BC in comparison to ZnO‐QDs was determined using the well diffusion method and an inhibition zone ranging from 11 to 23 mm and in the broth assay the OD values were reduced by almost seven and 10 times for ZnO‐BC and ZnO‐QDs, respectively, when compared to the control (untreated). The antibacterial activity demonstrated that our newly prepared BC and its QDs have superior activity when compared to the standard antibiotics such as ampicillin. This type of nanomaterial can be used as a new bioactive natural material with light‐assisted activity for antibacterial coatings in the manufacture of personal protective equipment. [ABSTRACT FROM AUTHOR]

This present study optimized the cellulose nanofiber (CNF) loading and melt processing conditions of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) P(HB-co-11% HHx) bionanocomposite fabrication in twin screw extruder by using the response surface methodology (RSM). A face-centered central composite design (CCD) was applied to statistically specify the important parameters, namely CNF loading (1–9 wt.%), rotational speed (20–60 rpm), and temperature (135–175 °C), on the mechanical properties of the P(HB-co-11% HHx) bionanocomposites. The developed model reveals that CNF loading and temperature were the dominating parameters that enhanced the mechanical properties of the P(HB-co-11% HHx)/CNF bionanocomposites. The optimal CNF loading, rotational speed, and temperature for P(HB-co-11% HHx) bionanocomposite fabrication were 1.5 wt.%, 20 rpm, and 160 °C, respectively. The predicted tensile strength, flexural strength, and flexural modulus for these optimum conditions were 22.96 MPa, 33.91 MPa, and 1.02 GPa, respectively, with maximum desirability of 0.929. P(HB-co-11% HHx)/CNF bionanocomposites exhibited improved tensile strength, flexural strength, and modulus by 17, 6, and 20%, respectively, as compared to the neat P(HB-co-11% HHx). While the crystallinity of P(HB-co-11% HHx)/CNF bionanocomposites increased by 17% under the optimal fabrication conditions, the thermal stability of the P(HB-co-11% HHx)/CNF bionanocomposites was not significantly different from neat P(HB-co-11% HHx). [ABSTRACT FROM AUTHOR]

Cellulose is one of the most frequently used and generally available materials on Earth and has been utilized for ages in a variety of applications. Numerous researchers have investigated various lignocellulosic sources for the extraction of cellulose and the author has introduced a new source for the extraction of cellulose and cellulosic nanofibers: fruits or seedpods of Delonix Regia (CNF). The solvent casting process is used to create the PVA/CNF composite after the cellulose and CNF have been removed using a mechano-chemical method. SEM, tensile testing, soil burial testing and moisture absorption tests have all been used to examine the morphological, mechanical, biodegradable and moisture absorption capabilities of pure PVA and PVA/CNF composite with 1, 3, 5, 7 and 9 percentages of CNF. According to SEM findings, agglomeration was seen at higher concentrations but uniform and homogenous distribution of nanofillers was seen at lower percentages of CNF. It is profusely clear from the results of the tensile tests that the percentage elongation initially decreased and then began to increase at higher concentration, while the Young's modulus and tensile strength initially increased at lower percentages of CNF rapidly and gradually decreased for higher concentration. Pure PVA had the least resistance to degradation in biodegradability test, while the biodegradability test showed that the inclusion of CNF decreased the composite material's ability to degrade. With the addition of CNF, the rate of moisture absorption decreased, resulting in a PVA/CNF composite material that will last longer and perform better without material degradation. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the effects of a combination of zinc oxide nanoparticles (Nano-ZnO) and fennel essential oil (FEO) on the quality characteristics of fresh pistachio. The potato starch-based films containing different levels of Nano-ZnO (1, 3, and 5% w/w), and FEO (1, 2, and 3% w/w) were prepared by the casting method. The fresh Akbari pistachios were packed in these bio-nanocomposite films. The physicochemical and sensory properties and the growth of Aspergillus flavus and aflatoxin B1 production were investigated during 15 days of refrigerated storage (~ 4°C). Results showed that by packaging fresh pistachios in bio-nanocomposite films, the moisture, carbohydrate, and fat contents of pistachios and the sensory parameters (texture, flavor, appearance, and overall acceptability) of them were improved during refrigerated storage. The weight loss of control significantly was higher than packed samples in bio-nanocomposite films (p

[Display omitted] • A bionanocomposite (BNC) was synthesized by incorporating NiO-MgO NPs into a chitosan and agar agar biopolymer matrix. • The synthesized CTAG@NiMg BNC exhibited 99.52% photocatalytic degradation of methyl orange (MO). • The CTAG@NiMg BNC demonstrated excellent reusability across four consecutive cycles without significant loss of activity. • Integration of NiO and MgO NPs with CTS-AA matrix increased the material's surface area to better dye degradation rates. In this study, NiO-MgO nanoparticles (NiMg NPs) were synthesized and incorporated into a biopolymer blend of chitosan (CTS) and agar agar gum (AA), forming the novel CTAG@NiMg bionanocomposite (BNC). Structural analysis revealed a crystal size of 19 nm and a direct band gap of 2.75 eV, indicating strong potential as a UV-active photocatalyst. TEM images confirmed uniform nanoparticle distribution with an average size of 25 nm. The elemental composition, verified by EDX spectra, showed weight percentages of C (21.32 %), O (31.47 %), Ni (35.39 %), and Mg (11.82 %). The CTAG@NiMg BNC demonstrated outstanding photocatalytic degradation of methyl orange (MO) dye, achieving 99.52 % degradation at pH 4 with 20-ppm concentration after 60 min under UV irradiation. The degradation followed pseudo-first-order kinetics, with rate constants (k 1) ranging from 0.011 to 0.030 min−1, and a minimum half-life of 25.8 min at 15 ppm. Hydroxyl radicals (•OH) were identified as the primary reactive species driving the photocatalytic process. The material exhibited excellent reusability, retaining high degradation efficiency over four cycles. Compared to similar photocatalysts, CTAG@NiMg BNC demonstrated superior performance, faster degradation rates, and greater stability. Its enhanced surface area and porosity, as confirmed by BET analysis, contributed to better dye adsorption and faster reaction times. These properties make the CTAG@NiMg BNC a highly efficient, sustainable, and recyclable photocatalyst for environmental remediation, particularly in treating organic pollutants like methyl orange from aqueous solutions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bioflocculant polymer reduced CuO/NiO nanocomposite. • Characterized using FT-IR, XRD, SEM and TEM techniques. • CuO/NiO nanocomposite used for non-enzymatic Glucose detection. • Amperometric detection of Glucose with wide linear range tested. • High selectivity, stability and reproducibility achieved. A bimetallic copper oxide/nickel oxide nanocomposite (CuO/NiO NCs) was synthesized via direct carbonization method by using microbial polymer as reducing agent. This nanocomposite was employed as a viable non-enzymatic electrocatalyst in the glucose detection. It was completely characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopic (EDX) methods and revealed the obtained porous nanoflower morphology with particle sizes of 100–200 nm in a monoclinic face-centered cubic crystalline structure. FT-IR spectra confirmed the presence of functional groups and the purity of the nanocomposite. Electrocatalytic performance for glucose oxidation was evaluated through cyclic voltammetric (CV) and amperometric i-t techniques. The observation demonstrated that the CuO/NiO NCs exhibited a remarkable electro-oxidation activity against glucose, attributed to the synergistic effects of the bimetallic components. As an electrode surface modifier, the CuO/NiO NCs facilitated an enhanced glucose oxidation over a linear range of 1–9 mM via CV, while amperometric i-t measurements achieved a detection range from 0.04 μM to 4.86 mM in a 0.1 M NaOH (pH ∼ 13) electrolyte solution. These eco-friendly and in-expensive nanoflowers displayed excellent selectivity, stability, and reproducibility, underscoring their potential in diabetes monitoring and the subsequent scientific analysis. [ABSTRACT FROM AUTHOR]

Numerous microbial species have caused infectious diseases worldwide, which have become a social burden and a menace to the community. So, there is a need to develop antimicrobial materials and specialized materials for biomedical applications. In the present investigation, we report the simple synthesis, the physicochemical, and antibacterial activity of Silver doped zinc sulfide (ZnS: Ag) capped with Chitosan (CS) to produce ZnS: Ag/CS bionanocomposites (BNCs). The prepared BNCs was evaluated by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) mapping, and UV–Vis spectroscopy. According to the XRD results, ZnS: Ag/CS particles with semicrystalline chitosan/hexagonal ZnS phase structures and an average crystallite size in the range of 30–40 nm was formed. According to FESEM images, a spherical/hexagonal shape of ZnS: Ag particles embedded in the polymeric chitosan matrix. The colony counting method was employed to investigate the antibacterial activity on Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. The results revealed that ZnS: Ag particles and ZnS: Ag/CS BNCs have stronger antibacterial activities than pure CS and ZnS. The reduction percentage of ZnS: Ag/CS BNCs against S. aureus and E. coli after 6 h of treatment was >99.9 % and 70 % respectively. These findings suggest that ZnS: Ag/CS BCs not only offer superior antimicrobial properties compared to individual ZnS and CS but also have great potential for advancing biomedical applications due to their enhanced antibacterial performance. The simplicity of the synthesis method and the use of non-toxic materials like chitosan make this a sustainable approach for developing antimicrobial agents, which is a key advantage of this study. [Display omitted] • The ZnS: Ag/CS BNCs were successfully prepared. • Ag doped zinc sulfide was loaded into chitosan. • Antibacterial activity enhancement of ZnS: Ag/CS BNCs was observed. • ZnS: Ag/CS BNCs showed >99.9% and 70% colony reduction percentage against Staphylococcus aureus and Escherichia coli bacteria, respectively [ABSTRACT FROM AUTHOR]

Herein, bionanocomposite beads based on Carboxymethyl cellulose/Dextrant sulfate (CMC/DS) embedding silver nanoparticle-functionalized zeolite (AgZ) were developed and proposed as catalysts for catalytic hydrogenation of Direct Red 16 (DR16) azo dye under different experimental parameters. The obtained results showed that AgZ incorporation into the polymer matrix produced highly porous structures with improved thermal stability. For antibacterial application, it was shown that the engineered bionanocomposites were effective against all tested bacteria. The CMC-DS-AgZ catalysts showed good catalytic performances for the hydrogenation of DR16 in various real-life water samples and even in presence of several mineral salts, however with a high efficiency (99 %) obtained for the catalyst prepared at elevated AgZ content (with a k app rate constant of 0.239 min−1). Moreover, the hydrogenation study of various azo dyes highlighted the satisfactory application potential of the catalysts and their versatility. The catalyst beads showed good recyclability for five successive cycles without any significant loss of efficiency or stability. The proposed mechanism for DR16 catalytic hydrogenation on C3-D1-AgZ revealed that AgZ could enhance the catalytic activity of the beads by facilitating the formation of Ag H intermediates. Finally, the green synthesized materials were shown to be viable and potential candidates for the purification of environmental media. • CMC-DS-AgZ as catalysts for the removal of azo dyes were proposed. • AgNPs were synthesized by a green process in situ in zeolite. • The catalysts exhibited excellent catalytic activity towards MO, DR16, CR and DB71 dyes. • CMC-DS-AgZ demonstrated high stability and durability over repeated cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biodegradation of poly(3-hydroxybutyrate) (PHB)-based films in natural environment. • Biodegradation of PHB proceeds via cleavage of ester bonds in the molecular chains. • Efficient biodegradation of PHB-based films in soil than in river water. • Amorphous regions in PHB-based films were degraded quickly and efficiently. • Number of chain scissions per unit mass increases with degradation time. The biodegradability of poly (3-hydroxybutyrate) (PHB)-based food packaging material PHB/5GS/0.7MgO, developed by incorporating 5 wt% grapeseed oil (GS) and 0.7 wt% MgO nanoparticles using solution casting route, was investigated in soil and river water environments. For comparison, the biodegradability of neat PHB films and PHB-based films loaded only with 5 wt% GS (PHB/5GS) was also studied. Remarkably, all PHB-based films showed 100 % weight loss in soil within 25 days. In contrast, the weight loss of PHB, PHB/5GS, and PHB/5GS/MgO films in river water was 27, 24, and 20 %, respectively, in 120 days. Gradual reduction in average molecular weight and carbonyl index, alongside an increase in crystallinity, opacity, and the number of chain scissions per unit mass, was observed for various PHB-based films during their degradation in soil and river water. Overall, this study demonstrated high degradation efficiency of PHB-based food packaging material in soil than in river water. [ABSTRACT FROM AUTHOR]

The present study aimed to synthesize gum katira-silver nanoparticle-based bionanocomposite. Different characterization techniques were used to analyze the synthesized bionanocomposite, such as Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), thermo-gravimetric analysis (TGA), and transmission electronic microscopy (TEM). AgNPs were formed and were 6–20 nm in size. Thermo-gravimetric analysis showed that synthesized nanocomposites are more thermally stable than gum katira. All the reaction conditions, such as time, temperature, pH, solvent, amount of nanoparticles, the concentration of the initiator, crosslinker, and monomer were optimized with respect to swelling. The results showed that the highest percentage swelling (Ps) of Gk-cl-poly(AA) was 796%, and 867% of AgNPs were imbibed by Gk-cl-poly(acrylic acid)-AgNPs. Synthesized bionanocomposite was used as an adsorbent material for the adsorption of methyl red (MR) dye. The effects of different reaction conditions were also optimized to attain maximum adsorption of MR dye. The maximum dye adsorption through Gk-cl-poly(AA)-AgNPs bionanocomposite was 95.7%. Diverse kinetic and isotherm models were used to study the adsorption data. The R2 value was established as 0.987 and k2 was .02671. The greater R2 value of second-order kinetics over first-order kinetics suggested that MR adsorption by nanocomposite is best explained by pseudo-second-order kinetics, indicating that dye adsorption occurred through chemisorption. The R2 value was determined to be .9954. The correlation coefficient values of Gk-cl-poly(AA)-AgNPs were best fitted by the Freundlich adsorption isotherm. Overall, synthesized bionanocomposite is a proficient material for removing of MR dye from wastewater.

Tannic acid in alkaline solutions in which sol-gel synthesis is usually performed with tetraethoxysilane is susceptible to various modifications, including formation of reactive radicals, oxidation under the action of atmospheric oxygen, self-association, and self-polymerization. Here, a precursor with ethylene glycol residues instead of ethanol was used, which made it possible to synthesize bionanocomposites of tannic acid and silica in one stage in neutral media under normal conditions without the addition of acid/alkali and organic solvents. Silica was fabricated in the form of optically transparent monoliths of various shapes with 2–4 nm pores, the radius of which well correlated with the size of a tannic acid macromolecule in a non-aggregated state. Polyphenol, which was remained in pores of silica matrix, served then as reducing agent to synthesize in situ gold and silver nanoparticles. As shown, these Au@SiO2 and Ag@SiO2 nanocomposites possessed localized surface plasmon resonance and high catalytic activity. [ABSTRACT FROM AUTHOR]

Exponential increase in the use and disposal of synthetic plastics has raised an alarming concern related to their adverse effect on the environment due to their recalcitrant nature and non biodegradability. Nevertheless, the depletion in the petrochemical sources made it imperative to search for other sustainable alternatives to synthetic plastics. This triggered the attention on biodegradable plastics produced from plants, animals and microbial sources that have excellent material properties like their synthetic counterparts. Polyhydroxyalkanoates (PHAs) are ineluctably promising microbial polyesters that have the competence to supersede traditional oil-based synthetic polymers which causes major disposal issues worldwide. The compostable nature, biocompatibility, thermostability, and resilience of these bio-based polymers make them an acceptable replacement in the global market. Their versatile material properties made them a propitious candidate in packaging, biomedicine, tissue engineering, biofuel production, nanocomposite formation, and other industrial applications. Despite their potential advantages, the commercialization of PHA is hindered majorly due to the high cost associated with their production and extraction. This review work majorly focuses on the production, extraction, applications and fermentation strategies for enhancing PHA production. The review also addresses the production of PHA from extremophiles, challenges associated with PHA production and sustainable substrates for PHA production using various agroindustrial wastes. [ABSTRACT FROM AUTHOR]

The influence of graphene oxide (GO) decoration with polyethylene glycol (PEG) on the thermal, mechanical, antibacterial, and also biocompatibility of chitosan (CS) biopolymer was investigated. GO-PEG nanohybrids were synthesized and characterized by FTIR, AFM, UV–Vis, and XRD. The results indicated significant changes in morphology, optical properties, interlayer distances, and aqueous stability of GO as a result of the linkage of PEG chains to the surface of GO nanoplates. Afterward, GO-PEG was added to CS as graphene-based hybrid nanosheets to reinforce CS-based environmental biofilms. Outcomes demonstrated that surface decoration of GO with PEG chains effectively improved compatibility and dispersion of GO plates in the CS matrix. Therefore bionanocomposites containing modified GO (CS/GO-PEG) exhibited superior thermal stability, mechanical and antibacterial properties as well as biocompatibility. CS/GO-PEG bionanocomposite with more desirable properties, than CS biopolymer and even CS/GO nanocomposite, can be preferred for biomedical applications (tissue engineering, wound dressing, drug delivery) and also food/drug packaging industry. [ABSTRACT FROM AUTHOR]

The surging demand for electronics is causing detrimental environmental consequences through massive electronic waste production. Urgently shifting toward renewable and eco-friendly materials is crucial for fostering a green circular economy. Herein, we develop a multifunctional bionanocomposite using an algae-derived carbohydrate biopolymer (alginate) and boron nitride nanosheet (BNNS) that can be readily employed as a multifunctional dielectric material. The adopted rational design principle includes spatial locking of superhigh loading of BNNS via hydrogel casting followed by layer-by-layer assembly via solvent evaporation, successive cross-link engineering, and hot pressing. We harness the hierarchical assembly of BNNS and the molecular interaction of alginates with BNNS to achieve synergistic material properties with excellent mechanical robustness (tensile strength ∼135 MPa, Young's modulus ∼18 GPa), flexibility, thermal conductivity (∼4.5 W m -1 K -1 ), flame retardance, and dielectric properties (dielectric constant ∼7, dielectric strength ∼400 V/μm, and maximum energy density ∼4.33 J/cm 3 ) that outperform traditional synthetic polymer dielectrics. Finally, we leverage the synergistic material properties of our engineered bionanocomposite to showcase its potential in green electronic applications, for example, supercapacitors and flexible interconnects. The supercapacitor device consisting of aerosol jet-printed single-walled carbon nanotube electrodes on our engineered bionanocomposite demonstrated a volumetric capacitance of ∼7 F/cm 3 and robust rate capability, while the printed silver interconnects maintained conductivity in various deformed states (i.e., bending or flexing).