Fingerprint fluorescence imaging has become one of the most prominent technologies in the field of forensic medicine, but it seldom considers the security protection of detection information, which ...is of great importance in modern society. Herein we demonstrate that luminescent TbIII–carboxymethyl cellulose (CMC) complex binding aptamer hydrogels that are reversibly responsive to ClO−/SCN− can be used for the selective detection, protection, and storage of fingerprint information. The imaging information of the fingerprint can be quenched and recovered by ClO−/SCN− regulation, respectively, resulting in reversible on/off conversion of the luminescence signals for the encryption and decryption of multiple levels of information. The present study opens new avenues for multilevel imaging, data recording, and security protection of fingerprint information with tunable fluorescent hydrogels.
Safe and secure: A hydrogel based on a luminescent TbIII–carboxymethyl cellulose complex was developed for the selective detection, protection, and storage of fingerprint information. The imaging information could be quenched with ClO− ions and recovered by the addition of SCN−, thus leading to reversible on/off switching of the luminescence signal for fingerprint information encryption and decryption.
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Biogenic, sustainable two-dimensional architectures, such as films and nanopapers, have garnered considerable interest because of their low carbon footprint, biodegradability, ...advanced optical/mechanical characteristics, and diverse potential applications. Here, bio-based nanopapers with tailored characteristics were engineered by the electrostatic complexation of oppositely charged colloidal phosphorylated cellulose nanofibers (P-CNFs) and deacetylated chitin nanocrystals (ChNCs). The electrostatic interaction between anionic P-CNFs and cationic ChNCs enhanced the stretchability and water stability of the nanopapers. Correspondingly, they exhibited a wet tensile strength of 17.7 MPa after 24 h of water immersion. Furthermore, the nanopapers exhibited good thermal stability and excellent self-extinguishing behavior, triggered by both phosphorous and nitrogen. These features make the nanopapers sustainable and promising structures for application in advanced fields, such as optoelectronics.
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•Platinum(Pt) was recovered from spent automobile catalyst leachate by bio-sorption.•Nanocellulose from various sources and types are modified with polyethyleneimine(PEI).•Cellulose ...nano fibril from tunicate(T-CNF) exhibits the highest PEI grafting density.•Pure cellulose form and open porous structure of T-CNF enhances the PEI density.•Pt adsorption capacity is proportionally increased by PEI density on nanocellulose.
Nanocellulose is a promising biosorbent for the recovery of precious metals from waste streams. A variety of nanocelluloses exhibit significant different properties that depend on the natural source and type. In this study, cellulose nanofibrils(P-CNF) and cellulose nanocrystals(P-CNC) obtained from hard wood pulp and CNF from tunicates(T-CNF) were evaluated for their ability to recover platinum(Pt) after modification with polyethyleneimine(PEI). The PEI grafting density on each nanocellulose was distinct, resulting in significant variations in the Pt adsorption performance. The Pt adsorption capacity of the PEI-modified nanocelluloses followed the order T-CNF>>P-CNC > P-CNF. The inherent characteristics of T-CNF, that is, the negative charge and high surface area caused by open porous structure, were found attributed to the grafting of ≈40% PEI and the excellent Pt adsorption capacity(≈600 mg/g). Also PEI-modified T-CNF exhibited high selectivity towards Pt in the presence of other metals. Finally, PEI modified T-CNF was applied for Pt recovery from simulated spent automobile catalyst leachate to prove feasibility in a real application.
The recent decade has witnessed a growing demand to substitute synthetic materials with naturally-derived platforms for minimizing their undesirable footprints in biomedicine, environment, and ...ecosystems. Among the natural materials, cellulose, the most abundant biopolymer in the world with key properties, such as biocompatibility, biorenewability, and sustainability has drawn significant attention. The hierarchical structure of cellulose fibers, one of the main constituents of plant cell walls, has been nanoengineered and broken down to nanoscale building blocks, providing an infrastructure for nanomedicine. Microorganisms, such as certain types of bacteria, are another source of nanocelluloses known as bacterial nanocellulose (BNC), which benefit from high purity and crystallinity. Chemical and mechanical treatments of cellulose fibrils made up of alternating crystalline and amorphous regions have yielded cellulose nanocrystals (CNC), hairy CNC (HCNC), and cellulose nanofibrils (CNF) with dimensions spanning from a few nanometers up to several microns. Cellulose nanocrystals and nanofibrils may readily bind drugs, proteins, and nanoparticles through physical interactions or be chemically modified to covalently accommodate cargos. Engineering surface properties, such as chemical functionality, charge, area, crystallinity, and hydrophilicity, plays a pivotal role in controlling the cargo loading/releasing capacity and rate, stability, toxicity, immunogenicity, and biodegradation of nanocellulose-based delivery platforms. This review provides insights into the recent advances in nanoengineering cellulose crystals and fibrils to develop vehicles, encompassing colloidal nanoparticles, hydrogels, aerogels, films, coatings, capsules, and membranes, for the delivery of a broad range of bioactive cargos, such as chemotherapeutic drugs, anti-inflammatory agents, antibacterial compounds, and probiotics.
Engineering certain types of microorganisms as well as the hierarchical structure of cellulose fibers, one of the main building blocks of plant cell walls, has yielded unique families of cellulose-based nanomaterials, which have leveraged the effective delivery of bioactive molecules.
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In this research, bamboo-based nanocellulose was prepared and characterized using high-speed ball milling to reduce initial bamboo powder particle size for potential use in nanocomposites. FTIR ...analysis revealed structural modifications, including increased cellulose content and decreased lignin content post-treatment. XRD analysis indicated a shift from cellulose I to cellulose II, suggesting altered crystallinity and hydrogen-bonding networks. SEM analysis revealed distinct morphological changes between untreated and NaOH-treated bamboo fibers, with the latter exhibiting surface modifications indicative of effective treatment. Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM) images demonstrated a reduction in particle size to approximately 80 nm, with reduced aggregation and individualized nanofibrils. Tensile tests of bamboo nanoparticle-epoxy biocomposites with varying weight percentages (0.5 %, 1 %, 1.5 %, and 2 %) of nanoparticles showed enhanced tensile strength up to 1.5 % loading (83.92 ± 1.74 MPa), but a decrease at 2 % loading (70.24 ± 1.80 MPa), indicating increased strain-to-failure. SEM and TEM images illustrated a homogeneous distribution at 1.5 wt%, but increased agglomeration at higher contents, impacting microstructure. This study underscores bamboo-derived nanocellulose's potential for tailored applications and improved mechanical properties in nanocomposites, highlighting the critical role of filler content in material performance and microstructure.
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•Bamboo-based nanocellulose synthesized via high-speed ball milling.•FTIR analysis showed an increase in cellulose content and a decrease in lignin content post-treatment.•XRD analysis revealed a shift towards cellulose II with increased crystallinity.•SEM analysis showed smooth and uniform surfaces in untreated bamboo fibers.•NaOH-treated bamboo fibers exhibited white spots indicating NaOH residues and altered surface chemistry.
Behavior of nanocelluloses at interfaces Capron, Isabelle; Rojas, Orlando J.; Bordes, Romain
Current opinion in colloid & interface science,
05/2017, Letnik:
29
Journal Article
Recenzirano
Despite being non-surface active, nanocelluloses position efficiently at interfaces, already at very low concentration. This behavior has lately triggered a strong interest in the cellulose and ...colloids communities. This review reports the recent developments on the use of nanocelluloses at interfaces and highlights the fundamental principles governing the high efficiency observed in reinforcing the boundary between two phases. The use of nanocelluloses as emulsifier and emulsion stabilizer is first discussed, and the structural properties of nanocelluloses such as aspect ratio and surface properties are correlated with the high efficiency in forming colloidally-stable multiphase systems. Then, the behavior at the air/water interface is presented and the most recent advances are reviewed with focus on the surface free energy of nanocelluloses and their role in the interfacial self-assembly process.
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Cellulose is the main structural component of plant cell walls. Cellulose is a fibrous, water-insoluble substance and is considered to be the most abundant bio-derived polymer on earth. From an ...industrial perspective, plant cellulose has been the mainstay of the wood industries for the past 100 years. The hierarchical organization and semicrystalline nature of cellulose found in plant fibers allows the extraction of nanofibers and nanocrystals using mechanical and chemical top-down de-structuring strategies. Bacterial cellulose has also been increasingly investigated. Bacterial cellulose is composed of cellulose nanofibers secreted extracellularly by some bacteria; bacterial cellulose is therefore obtained using bottom-up synthesis. The unique nanofibrillar structure of bacterial cellulose confers excellent physical and mechanical properties such as high porosity, high elastic modulus and high crystallinity. Research on nanocellulose is accelerating due actual fossil fuel issues such as CO
2
emissions, plastic pollution and lack of renewable energy. Nanocellulose materials are non-toxic, biodegradable and recyclable, with no adverse effects on health and the environment. Here, we review cellulose production methods, properties and applications, focusing on the food industry, biomedical materials and electronic devices. We compare vegetal nanocellulose and bacterial cellulose. The increase in the number of publications on nanocellulose is also discussed.
Different adsorbents have been applied to remove various anionic pollutants in water treatment processes. However, the development of economic, sustainable, and high-performance adsorbents is still a ...challenge. Herein, we introduce a new strategy to produce highly porous (98.96%), very low density (0.015 g/cm3), and cost-effective spherical and nanostructured hybrid aerogels, termed aerobeads, from cellulose nanofibers (CNF) and metal-organic frameworks (MOFs). The zwitterionic MOFs@CNF aerobeads (with 10–50 wt% MOF loading) were synthesized via simple dropping of a cross-linked hydrogel containing CNF and a binary mixture of anionic and cationic MOFs in liquid nitrogen, followed by freeze-drying. The flexible aerobeads (diameter of 2–3 mm) with hierarchical porous structure demonstrated an outstanding adsorption capacity toward both diclofenac (121.20 mg/g) and methyl orange (49.21 mg/g). Moreover, the aerobeads were easily collected after use from the solution without any complicated separation methods or the formation of secondary pollutants.
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•A novel freeze-drying approach for fabrication of functional, highly porous nanocellulose aerobeads was introduced.•Zwitterionic aerobeads were obtained by mixing of anionic (HKUST-1) and cationic (ZIF-67) MOFs in nanocellulose framework.•The aerobeads showed an outstanding adsorption toward both diclofenac (121.20 mg/g) and methyl orange (49.21 mg/g).
This review outlines the present state and recent progress in the area of lignin-containing cellulose nanofibrils (LCNFs), an emerging family of green cellulose nanomaterials. Different types of LCNF ...raw materials are described, with main focus on wood-based raw materials, and the properties of the resulting LCNFs are compared. Common problems faced in industrial utilization of CNFs are discussed in the light of potential improvements from LCNFs, covering areas such as chemical and energy consumption, dewatering and redispersibility. Out of the potential applications, barrier films, emulsions and nanocomposites are considered.
•BNC films were modified by immersion in bio-extracts.•Bio-extracts are natural cost-effective means of imparting antibacterial property.•Antibacterial BNC films can be useful as wound dressings, ...biomasks, textile designing, etc.•Low cost antibacterial nanocellulose opens up new avenues to obtain cheaper and “all-natural” BNC-based products.
This study explores the modification of bacterial nanocellulose (BNC), produced in fermented tea medium with bio-extracts from herbal plants, to produce entirely natural antibacterial nanocellulose films. The antibacterial property was imparted by impregnating the synthesized BNC into bio-extracts of Terminalia arjuna (arjuna), Azadirachta indica (neem), Withania somnifera (ashwagandha), Tinospora cordifolia (giloy), and Murraya koenigii (curry leaves). FE-SEM analysis of modified BNC films revealed the presence of cloudy layer of bio-extracts over the BNC nanofibrous network. The modified BNC production was confirmed by ATR-FTIR. The modified BNC showed tremendous antibacterial activity against Escherichia coli (E. coli) and Aerococcus viridians (A. viridans). T. arjuna modified BNC showed the highest antibacterial activity against E. coli and A. viridans with inhibition zone of 27.08 mm and 26.34 mm, respectively, while M. koeniggi modified BNC showed the lowest antibacterial activity for both E. coli and A. viridans with inhibition zone of 14 mm and 14.2 mm, respectively. The water retention, moisture content and porosity values reflect highly hydrophilic nature of BNC films and their well suitability for varied biomedical applications like antibacterial wound dressings, herbal biomasks, scaffoldings, etc. The modification of BNC films with the bio-extracts used in this study has not been reported previously.
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