Search Results (47)

Nanocellulose, including cellulose nanofibers (CNFs), cellulose nanocrystals (CNCs), and bacterial nanocellulose (BNC), represents a promising class of bio-based nanomaterials derived from natural sources. These materials, derived from plant-based cellulose, are characterized by exceptional mechanical strength, high surface area, biodegradability, and the ability to form stable nanoparticle networks, making them suitable for use in composites, biomedicine, electronics, and many other fields. In this review, we present the latest advancements in the production of nanocellulose, including preparation technologies and methods for chemical and physical modifications to enhance the performance of these materials. We also discuss various applications, such as its use in nanocomposites, sustainable packaging materials, flexible electronic devices, and as a support for biological media. Additionally, the challenges and opportunities related to the scalability of production and their integration into industries with growing economic and ecological demands are explored. The review provides a comprehensive overview of the potential of nanocellulose, highlighting its importance in the context of emerging technologies and sustainability. Full article

Eggs are perishable mainly due to moisture loss and bacterial contamination. Herein, we developed an efficient and sustainable coating emulsion for egg preservation, which is primarily composed of cellulose nanofibrils (CNFs), coconut oil (CO), cinnamaldehyde, and sophorolipids. The effects of weight ratios of CO to CNFs on emulsion stability and the crucial properties of the resulting coatings were systematically investigated. Under the optimal weight ratio of 1:1, the emulsion demonstrated excellent stability, with a zeta potential of −50.86 mV, and the coating exhibited a low water vapor transmission rate of 18.19 g mm m⁻² day⁻¹. Moreover, the addition of cinnamaldehyde and sophorolipids enhanced the antibacterial properties of the coating and the wettability of the emulsion on eggshells. After 4 weeks of storage at 25 °C, the eggs coated with the developed emulsion deteriorated from AA to A grade, while those coated with mineral oil and the uncoated eggs deteriorated to B grade. Overall, this work presents a promising, sustainable, easily scalable, and highly efficient technique for fresh egg preservation, which holds great potential for practical applications in the egg storage industry. Full article

Functionalized plasmonic nanostructure platforms are widely used for developing optical biosensors and SERS assays. In this work, we present a low-cost and scalable surface-enhanced Raman scattering (SERS) system based on an innovative optical transducer comprising gold nanoparticles (AuNPs) embedded in nano-fibrillated bacterial cellulose (BC). The AuNPs@BC composite leverages the unique nanofibrillar architecture of bacterial cellulose, which provides a high surface area, flexibility, and uniform nanoparticle distribution, enabling the formation of numerous electromagnetic “hot spots”. This structure excites localized surface plasmon resonance (LSPR), as demonstrated by a bulk sensitivity of 72 nm/RIU, and supports enhanced Raman signal amplification. The eco-friendly and disposable AuNPs@BC platform was tested for agrifood applications, focusing on the detection of thiram pesticide. The system achieved a detection limit of 0.24 ppm (1 µM), meeting the sensitivity requirements for regulatory compliance in food safety. A strong linear correlation (R² ≈ 0.99) was observed between the SERS peak intensity at 1370 cm⁻¹ and thiram concentrations, underscoring its potential for quantitative analysis. The combination of high sensitivity, reproducibility, and environmental sustainability makes the AuNPs@BC platform a promising solution for developing cost-effective, flexible, and portable sensors for pesticide monitoring and other biosensing applications. Full article

Paper-based cultural relics experience aging and deterioration during their long-term preservation, which poses a serious threat to their lifetime. The development of conservation materials with high compatibility and low intervention has been expected to extend the lifetime of paper artifacts. As a new type of biological macromolecule, nanocellulose has been extensively utilized in paper conservation, attributed to its excellent paper compatibility, high optical transparency, outstanding mechanical strength, and large specific surface area with abundant hydroxyl groups. This review systematically summarizes the latest development of three kinds of nanocellulose (cellulose nanofibril, cellulose nanocrystal, and bacterial nanocellulose) and their composites used for the multifunctional conservation of paper relics. Owing to the strong hydrogen bond interactions between hydroxyls of nanocellulose and paper fibers, nanocellulose can effectively consolidate paper without adding adhesives. The composite of nanocellulose with other functional materials greatly expands its application scope, and the superior performance has been emphasized in paper deacidification, consolidation, antimicrobial effect, antioxidation, UV resistance, self-cleaning, promotion of printing property, reduction in air permeability, and flame retardancy. The application characteristics and future prospects of nanocellulose composites are highlighted in the conservation of paper-based cultural relics. Full article

Nano-fibrillated bacterial cellulose (NFBC) has very long fibers (>17 μm) with diameters of approximately 20 nm. Hence, they have a very high aspect ratio and surface area. The high specific surface area of NFBC can potentially be utilized as an adsorbent. However, NFBC has no functional groups that can bind metal ions, limiting its potential applications. In this study, the hydroxyl groups on the surface of NFBC were chemically modified with EDTA monoanhydride to convert NFBC into a metal adsorbent. The fiber morphology and crystal structures of the modified NFBC were almost identical to those of the unmodified NFBC, suggesting that the surface hydroxyl groups of NFBC were well-conjugated with the EDTA groups. Surface-modified NFBC preferentially adsorbed transition metals in aqueous solutions, such as Cu(II), Hg(II), Pb(II), and Cd(II), but hardly adsorbed Mg(II) and Cr(VI). The adsorption of heavy metal ions can be explained by the pseudo-second-order kinetics of the chemisorption process and the Langmuir isotherm model. Furthermore, the EDTA-modified NFBC is a renewable and recyclable adsorbent. The results of this study indicate that surface-modified NFBC can be utilized as a biosorbent for heavy metal removal in chemical, food, pharmaceutical, and other industrial fields. Full article

This study aimed to address issues related to hydrophilicity, barrier properties, and mechanical performance in starch-based films by incorporating Pickering emulsions stabilized with nano-fibrillated bacterial cellulose (BC). Emulsions were added to the film-forming suspension at varying concentrations (1.0%, 2.5%, 5.0%, and 7.5% v/v) for comparison. The films were evaluated using water vapor permeability (WVP), contact angle, Fourier Transform Infrared Spectroscopy (FTIR), and tensile tests. The results showed a significant reduction in film hydrophilicity, with the contact angle increasing from 49.7° ± 1.5 to 71.0° ± 1.4, and improved water vapor barrier properties, with WVP decreasing from 0.085 ± 0.04 to 0.016 ± 0.01 g·mm/h·m²·kPa. FTIR analysis confirmed the successful incorporation of the emulsion into the starch matrix. Among the tested concentrations, 2.5% provided an optimal balance, increasing hydrophobicity while maintaining mechanical strength. These findings demonstrate that Pickering emulsions are an effective strategy for enhancing the functional properties of starch films. Full article

This study aimed to use waste figs as an alternative substrate for bacterial cellulose (BC) production by Komagataeibacter xylinus and optimize the identified process parameters to maximize the concentration of BC. Among the nutrients screened by Plackett–Burman (PB) design, yeast extract was found to be significant in BC production. Response surface methodology was used to investigate the effect of fermentation parameters on BC production. A maximum BC concentration of (8.45 g/L), which is among the highest BC concentrations reported so far, was achieved at the optimum levels of fermentation variables (initial pH 6.05, initial sugar concentration 62.75 g/L, temperature 30 °C). The utilization of response surface methodology (RSM) proved valuable in both optimizing and finding the interactions between process variables during BC production. Scanning electron microscope (SEM) analysis showed a dense structure of BC, characterized by ribbon-like nanofibrils with diameters ranging from 23 to 90 nm while the attenuated total reflection–Fourier transform infrared (ATR-FTIR) spectrum of BC confirmed that the material obtained was cellulose. The X-ray diffraction (XRD) analysis showed that the crystallinity of the BC samples was 70% for BC produced on waste fig medium and 61% for BC produced on Hestrin–Schramm (HS) medium. This is the first detailed study on the production of BC from waste figs, and the findings of this study demonstrated that waste figs can be used as an effective substrate for the production of BC. Full article

Nanocelluloses have gained significant attention in recent years due to their singular properties (good biocompatibility, high optical transparency and mechanical strength, large specific surface area, and good film-forming ability) and wide-ranging applications (paper, food packaging, textiles, electronics, and biomedical). This article is a comprehensive review of the applications of nanocelluloses (cellulose nanocrystals, cellulose nanofibrils, and bacterial nanocellulose) in the conservation and restoration of historical paper documents, including their preparation methods and main properties. The novelty lies in the information collected about nanocelluloses as renewable, environmentally friendly, and sustainable materials in the field of cultural heritage preservation as an alternative to conventional methods. Several studies have demonstrated that nanocelluloses, with or without other particles, may impart to the paper documents excellent optical and mechanical properties, very good stability against temperature and humidity aging, higher antibacterial and antifungal activity, high protection from UV light, and may be applied without requiring additional adhesive. Full article

Bacterial cellulose, as an important renewable bioresource, exhibits excellent mechanical properties along with intrinsic biodegradability. It is expected to replace non-degradable plastics and reduce severe environmental pollution. In this study, using dry jet-wet spinning and stretching methods, we fabricate cellulose composite macrofibers using nanofibrillated bacterial cellulose (BCNFs) which were obtained by agitated fermentation. Ionic liquid (IL) was used as a solvent to perform wet spinning. In this process, force-induced alignment of BCNFs was applied to enhance the mechanical properties of the macrofibers. The results of scanning electron microscopy revealed the well-aligned structure of BCNF along the fiber axis. The fiber prepared with an extrusion rate of 30 m min⁻¹ and a stretching ratio of 46% exhibited a strength of 174 MPa and a Young’s modulus of 13.7 GPa. In addition, we investigated the co-spinning of carboxymethyl cellulose-containing BCNF with chitosan using IL as a “container”, which indicated the compatibility of BCNFs with other polysaccharides. Recycling of the ionic liquid was also verified to validate the sustainability of our strategy. This study provides a scalable method to fabricate bacterial cellulose composite fibers, which can be applied in the textile or biomaterial industries with further functionalization. Full article

Bacterial cellulose (BC) is a highly crystalline nanosized material with a high number of active groups. This study focuses on the synthesis of BC membranes through fermentation, their characterization and application to remove Ni(II) and Pb(II) from wastewater by adsorption under different conditions. Four-day-grown BC membranes form three-dimensional nanofibril networks with a pH of 6.3 and a high cationic demand (52.5 μeq·g⁻¹). The pseudo-second-order kinetic model and the Sips isotherm model best describe the adsorption of both metals. The intraparticle diffusion model of Ni(II) revealed a three-step mechanism of adsorption-plateau-adsorption, while Pb(II) adsorption followed a typical reducing-slope trend up to saturation. The highest removal of Ni(II) and Pb(II) was obtained at pH 4 with a BC dosage of 400 mg·L⁻¹. The maximum adsorption capacities were 28.18 mg·g⁻¹ and 8.49 mg·g⁻¹ for Ni(II) and Pb(II), respectively, involving the total coverage of the material active sites. Thermodynamically, Ni(II) adsorption was exothermic, and Pb(II) was endothermic. The obtained values of sorption heat, activation and Gibbs’ energy depicted a physisorption process. Ni(II) removal mechanism was ruled by crystallization on the metals adsorbed on the BC active groups, while Pb(II) was driven by the adsorption process, as shown by TEM images of the spent material. Full article

Nanocellulose (NC) is an emerging natural material that offers great potential for various applications due to its unique properties and renewable character. Nowadays, as NC production technologies are advancing, it is essential to evaluate their economic feasibility, technological maturity and commercialization potential using systematic techno-economic analysis (TEA). The present study considers both technical and economic aspects of NC production and analyzes them in two ways: first, by developing a new concept based on the production of different types of NC through the conversion of lignocellulosic biomass by chemical and mechanical technologies, and second, by a comparative review of existing TEA studies in the open literature. Three specific scenarios and two case studies are evaluated by comparing specific key performance indicators (KPIs), such as the production cost (PC) and minimum product selling price (MPSP) of NC. As a result, a short though comprehensive overview of the current state of NC production is provided, highlighting the main technical and economic challenges associated with it. Key areas for future research and innovation (R&I) are also identified to optimize the production processes and reduce relevant costs, in order to make NC competitive with existing materials and realize its full potential. Full article

Primary material supply is the heart of engineering and sciences. The depletion of natural resources and an increase in the human population by a billion in 13 to 15 years pose a critical concern regarding the sustainability of these materials; therefore, functionalizing renewable materials, such as nanocellulose, by possibly exploiting their properties for various practical applications, has been undertaken worldwide. Nanocellulose has emerged as a dominant green natural material with attractive and tailorable physicochemical properties, is renewable and sustainable, and shows biocompatibility and tunable surface properties. Nanocellulose is derived from cellulose, the most abundant polymer in nature with the remarkable properties of nanomaterials. This article provides a comprehensive overview of the methods used for nanocellulose preparation, structure–property and structure–property correlations, and the application of nanocellulose and its nanocomposite materials. This article differentiates the classification of nanocellulose, provides a brief account of the production methods that have been developed for isolating nanocellulose, highlights a range of unique properties of nanocellulose that have been extracted from different kinds of experiments and studies, and elaborates on nanocellulose potential applications in various areas. The present review is anticipated to provide the readers with the progress and knowledge related to nanocellulose. Pushing the boundaries of nanocellulose further into cutting-edge applications will be of particular interest in the future, especially as cost-effective commercial sources of nanocellulose continue to emerge. Full article

The environmental impacts of the exploration and use of petroleum and derivatives in recent decades have led to increasing interest in novel materials and processes for the treatment of oily effluents. Oily emulsions are difficult to manage and, in some cases, require different types of treatment or combined methods for phase separation. Sustainable, versatile, innovative biomaterials, such as bacterial cellulose (BC), have considerable applicability potential in mixture separation methods. In the present study, a cellulose membrane produced by a symbiotic culture of bacteria and yeasts (SCOBY) was investigated with the aim of measuring the characteristics that would enable its use in the treatment of oily wastewater. BC was analyzed through physicochemical characterizations, which demonstrated its porosity (>75%), chemical structure with high cellulose content and a large quantity of intramolecular H bonds, good thermal stability with maximum degradation at temperatures close to 300 °C, high crystallinity (66%), nanofibrils of approximately 84 nm in diameter and mechanical properties that demonstrated tensile strength of up to 65.53 Mpa, stretching of approximately 18.91% and the capacity to support a compression load of around 5 kN with only the loss of free water in its structure. The characteristic data of the membranes were used for the production of a filtering module for oily mixture separation processes. This support was developed with computational fluid dynamics of finite volumes and finite element structural analysis using advanced computer-assisted engineering tools. Lastly, the conceptual, basic project of a low-cost nanofiltration module was obtained; this module could be expanded to the industrial scale, operating with several modules in parallel. Full article

Low-cost, readily available, or even disposable membranes in water purification or downstream biopharma processes are becoming attractive alternatives to expensive polymeric columns or filters. In this article, the potential of microfiltration membranes prepared from differently orientated viscose fibre slivers, infused with ultrafine quaternised (qCNF) and amino-hydrophobised (aCNF) cellulose nanofibrils, were investigated for capturing and deactivating the bacteria from water during vacuum filtration. The morphology and capturing mechanism of the single- and multi-layer structured membranes were evaluated using microscopic imaging and colloidal particles. They were assessed for antibacterial efficacy and the retention of selected bacterial species (Escherichia coli, Staphylococcus aureus, Micrococcus luteus), differing in the cell envelope structure, hydrodynamic biovolume (shape and size) and their clustering. The aCNF increased biocidal efficacy significantly when compared to qCNF-integrated membrane, although the latter retained bacteria equally effectively by a thicker multi-layer structured membrane. The retention of bacterial cells occurred through electrostatic and hydrophobic interactions, as well as via interfibrous pore diffusion, depending on their physicochemical properties. For all bacterial strains, the highest retention (up to 100% or log 6 reduction) at >50 L/h∗bar∗m² flow rate was achieved with a 4-layer gradient-structured membrane containing different aCNF content, thereby matching the performance of industrial polymeric filters used for removing bacteria. Full article

Drug-loaded mono- and multilayer composite membranes were prepared. The composites, based on nano-fibrillated bacterial cellulose, nano-powdered bacterial cellulose, and polyvinyl alcohol, all biocompatible and biodegradable, were characterized in terms of basic factors related to drug diffusivity and mass transfer: swelling ability, water solubility, and water vapor permeability. Tetracycline hydrochloride was used in this case as drug model. Drug release was evaluated in an aqueous environment for two concentration levels of the antibiotic, and mathematical modeling was applied to fit experimental data. Tetracycline release was influenced by a membranes’ structure, layers’ composition, and by a membranes’ thickness. Bacterial cellulose nanofibrils proved to be the key factor in achieving suitable drug release profiles. Thus, sustained antibiotic delivery was obtained for several days in the case of multilayer composites. The composites proved drug stability and antibacterial efficiency before and after TC-HCl continuous release for several days. Full article