Cellulose-based Hydrogel Research Articles

Flame Retardant Cellulose-Based Hybrid Hydrogels for Firefighting and Fire Prevention

Flame Retardant Cellulose-Based Hybrid Hydrogels for Firefighting and Fire Prevention

Sugarcane cellulose-based composite hydrogel enhanced by g-C3N4 nanosheet for selective removal of organic dyes from water.

The effective removal of toxic dyes from aqueous solution is of great significance for environmental protection. Herein, an eco-friendly sugarcane cellulose (SBC)/sodium carboxymethylcellulose (CMC-Na) adsorbent reinforced with carbon nitride (g-C3N4) was successfully prepared via a facile sol-gel method. The resulting gel-like adsorbent or composite hydrogel was comprehensively characterized with FTIR, SEM, EDS, TGA analysis. The adsorption behaviors of the adsorbent in the removal of methylene blue (MB) were systematically investigated. Results showed the pseudo-second-order kinetic model and Langmuir model described adsorption process accurately with the maximum adsorption capacity of 362.3mgg-1, indicating that adsorption behavior is a monolayer chemical adsorption. Moreover, the composited hydrogel displayed excellent adsorption selectivity on MB/MO or MB/RhB mixed dyes. In addition, adsorbent showed great stability and reusability with almost no loss in adsorption capacity after 7cycles. Due to the facile preparation process and outstanding mechanical properties, as well as high recyclability, g-C3N4@SBC/CMC has great potential in wastewater treatment.

Bacterial cellulose-based hydrogel thermocells for low-grade heat harvesting

• A BC-based hydrogel TEC via a simple impregnation process was prepared. • The feasibility of BC hydrogel as a thermoelectric matrix was confirmed. • TEC generated 0.82 V voltage and 4.5 μW power with 3 pairs of units, at ΔT = 50 K. The hydrogel thermoelectrochemical cells (thermocells, TECs) are a simple, efficient, and inexpensive technology for harvesting low-grade heat from the environment. For the current development, higher mechanical properties and relatively simple and mature production processes are highly desirable and challenging. Herein, readily available bacterial cellulose (BC)-based TECs with Fe(CN) 6 3−/4− redox couple and Fe 2+/3+ redox couple as n, p-type cellulose hydrogel electrolyte via a simple impregnation process are prepared. The Seebeck coefficient can reach 4.5 mV∙K −1 for n-type TEC and 0.72 mV∙K −1 for p-type TEC. The proof-of-concept thermoelectric device, connecting in series with 3 pairs of units, can generate 0.82 V voltage and 4.5 μW peak power. The bacterial cellulose matrix is commercially available and can be produced in a large area, demonstrating the hope of being an energy carrier of thermoelectric ions for thermoelectric energy conversion. The bacterial cellulose-based TECs have potential applications in wearable electronic devices, energy storage devices, temperature sensing devices and so on.

Hydrochar-embedded carboxymethyl cellulose-g-poly(acrylic acid) hydrogel as stable soil water retention and nutrient release agent for plant growth

The cellulose-based hydrogel has been widely applied for soil water retention and nutrient release agents for several decades. Embedding the inorganic materials into hydrogels is an excellent strategy to improve the inherent limits of the cellulose-based hydrogel. Notably, municipal sludge-derived hydrochar (HC) has reduced the environmental burden and offered a potential hydrogel carrier to control water-retention and nutrient-release. However, the above function for plant growth of hydrochar-embedded carboxymethyl cellulose-g-poly(acrylic acid) (CMC-g-PAA/HC) is unknown, and relevant reports are lacking. This study investigated the water retention, nutrient release behavior, and effect of germination and plant growth of CMC-g-PAA/HC hydrogel. Characterization results showed that HC was successfully incorporated into CMC-g-PAA/HC with 6.0% higher thermostability, 7.2–21.0% lower swelling ratio (SR) in water, and substantial SR in phosphate solution (P-solution). The water loss rate of CMC-g-PAA/HC in P-solution or water owned a more significant temperature response (7.9–15.0 folds) than CMC-g-PAA (8.2–10.0 folds). Moreover, 4.0% higher n value and more 18.5% released P for CMC-g-PAA/HC were also observed. These phenomena were due to restricting the polymer chains movement and the water molecules diffusion inside the hydrogels with HC. Phytotoxicity assessments showed that HC in CMC-g-PAA/HC could effectively alleviate the inhibition effects on rape germination retained with 78.3% germination vigor and 80.0% germination ratio, even dramatically improved plant growth to 28 d. The results of this study demonstrated a new route for developing eco-friendly CMC-g-PAA/HC hydrogel, advantageous as a water retention agent and nutrient carrier in arid and semiarid regions.

Carboxymethyl cellulose-based nanocomposite hydrogel grafted with vinylic comonomers: synthesis, swelling behavior and drug delivery investigation

Carboxymethyl cellulose-based nanocomposite hydrogel was produced through in-situ free-radical copolymerization for use in drug delivery study. The pure hydrogel and their nanocomposite structure were systematically identified by XRD, FTIR, SEM, TEM, TGA-DTA techniques. The swelling and deswelling properties, which are affected by several factors such as pH (due to the carboxylate groups) and time were studied. The swelling rate improved with the SiO2 nanoparticles. Also, the swelling ratio in NaCl, CaCl2 and AlCl3 salt solutions were investigated and it was found that swelling capacity was 41 and 37 g/g for pure and nanocomposite hydrogel in NaCl solution, respectively. Diclofenac sodium was utilized as a model of drug and the drug release after loaded in the nanocomposite hydrogels was studied. The results revealed essential performances on the subject of physiological-simulated pH media. The maximum cumulative drug releases attained were 90.13% and 79.26% at pH values of 7.4 for nanocomposite and pure hydrogel, respectively. The applicability of drug release kinetic models such as Ritger–Peppas, zero and first-order kinetic models was proved. According to the information obtained from Ritger–Peppas model, the drug release mechanism follows non-Fickian diffusion and indicates an anomalous transport.

Cellulose-based hydrogel on quantum dots with molecularly imprinted polymers for the detection of CA19-9 protein cancer biomarker.

Molecularly imprinted polymers MIPs were successfully assembled around quantum dots (QDs), for the detection of the protein biomarker CA19-9 associated to pancreatic cancer (PC). These imprinted materials MIP@QDs were incorporated within the cellulose hydrogel with retention of its conformational structure inside the binding cavities. The concept is to use MIPs which function as the biorecognition elements, conjugated to cadmium telluride QDs as the sensing system. The excitation wavelength was set to 477nm and the fluorescence signal was measured at its maximum intensity, with an emission range between 530 and 780nm. The fluorescence quenching of the imprinted cellulose hydrogels occurred with increasing concentrations of CA19-9, showing linearity in the range 2.76 × 10 -2 - 5.23 × 10 2 U/ml, in a 1000-fold diluted human serum. Replicates of the imprinted hydrogel show a linear response below the cut-off values for pancreatic cancer diagnosis (< 23 U/ml), a limit of detection of 1.58 × 10 -3 U/ml and an imprinting factor (IF) of 1.76. In addition to the fact that the imprinted cellulose hydrogel displays good stability and selectivity towards CA19-9 when compared with the non-imprinted controls, the conjugation of MIPs to QDs increases the sensitivity of the system for an optical detection method towards ranges within clinical significance. This fact shows potential for the imprinted hydrogel to be applied as a sensitive, low-cost format for point-of-care tests (PoCTs).

RHEOLOGICAL PROPERTIES OF HYDROGELS PRODUCED BY CELLULOSE DERIVATIVES CROSSLINKED WITH CITRIC ACID, SUCCINIC ACID AND SEBACIC ACID

"Cellulose is the most abundant biopolymer in our world, and a natural, biodegradable and inexpensive resource for biomaterials. This work prepared cellulose-based hydrogels by cross-linking cellulose derivatives using citric acid, succinic acid, and sebacic acid, and explored the rheological properties of the three cellulose-based hydrogels. We found that the viscoelastic properties of this kind of cellulose-based biodegradable hydrogels can be manipulated by hydrogel concentration and using the three different cross-linkers. The cellulose-based hydrogels cross-linked with citric acid (CHCCA) and the cellulose-based hydrogels cross-linked with succinic acid (CHCSUA) exhibited nearly identical rheological behaviors (both linear and non-linear), due to the similar structure of the citric acid and succinic acid. Both CHCCA and CHCSUA showed similar viscoelastic solid gel-like behaviors, and the viscoelastic properties were stronger when hydrogel concentrations were increased. The CHCCA and CHCSUA also displayed nearly identical shear thinning behaviors, among all measured shearing rates. The cellulose-based hydrogels cross-linked with sebacic acid (CHCSEA) exhibited viscoelastic liquid or fluid-like behaviors, which are clearly different from those for the CHCCA and CHCSUA. The CHCSEA showed shear thinning characteristics during high shearing rates, but a Newtonian region at low shearing rates. This work paves the way for developing various inexpensive biodegradable cellulose-based hydrogels with desired rheological properties specific to applications such as cosmetic gels and woundhealing materials."

Self-assembling fluorescent hydrogel for highly efficient water purification and photothermal conversion

• The sulfydryl-based CDs (CDs-SH) displayed a selective, sensitive detection towards Hg(II). • Cellulose hydrogel with CDs-SH was self-assembled for simultaneously detecting and removing Hg(II). • CDs-SH hydrogel showed over 98% uptake efficiency and good detection ability for Hg(II). • The exhausted absorbents were upcycled via in-situ sulfurization for solar steam generation. • High evaporation rate of 1.30 kg m −2 h −1 and efficiency of 88.3% was achieved under one sun irradiation. Employing fluorescent hydrogels for hazardous Hg(II) detection and removal is an efficient method for water purification. However, it remains challenging to establish a fluorescent system with low detection limit and high adsorption capacity that can readily be upcycled into a valuable material resource. Herein, we report on a fluorescent hydrogel with 0D sulfydryl-based carbon dots that are self-assembled with a 3D hydrogel network. The cellulose-based hydrogel exhibited good sensitivity for the detection of Hg(II) over a range from 0 to 40 µM with a limit detection of 3.0 × 10 -6 M. The adsorption experiments confirmed that the cellulose-based hydrogel exhibits good Hg(II) extraction capacity of over 662.25 mg g −1 at room temperature, and can effectively reduce the Hg concentration to attain acceptable levels that comply with industrial water standards (0.05 mg L -1 ). Subsequently, we used a facile strategy to convert the exhausted waste adsorbent by in-situ sulfurization into a suitable material for solar steam generation. The as-prepared upcycled aerogel evaporators exhibited excellent evaporation rates of ∼ 1.30 kg m −2 h −1 under one sun irradiation. These results not only provide a strategy for heavy metal ion recognition and adsorption, but also provide a route to recycle hazardous waste for seawater desalination.

Cellulosic-Based Conductive Hydrogels for Electro-Active Tissues: A Review Summary.

The use of hydrogel in tissue engineering is not entirely new. In the last six decades, researchers have used hydrogel to develop artificial organs and tissue for the diagnosis of real-life problems and research purposes. Trial and error dominated the first forty years of tissue generation. Nowadays, biomaterials research is constantly progressing in the direction of new materials with expanded capabilities to better meet the current needs. Knowing the biological phenomenon at the interaction among materials and the human body has promoted the development of smart bio-inert and bio-active polymeric materials or devices as a result of vigorous and consistent research. Hydrogels can be tailored to contain properties such as softness, porosity, adequate strength, biodegradability, and a suitable surface for adhesion; they are ideal for use as a scaffold to provide support for cellular attachment and control tissue shapes. Perhaps electrical conductivity in hydrogel polymers promotes the interaction of electrical signals among artificial neurons and simulates the physiological microenvironment of electro-active tissues. This paper presents a review of the current state-of-the-art related to the complete process of conductive hydrogel manufacturing for tissue engineering from cellulosic materials. The essential properties required by hydrogel for electro-active-tissue regeneration are explored after a short overview of hydrogel classification and manufacturing methods. To prepare hydrogel from cellulose, the base material, cellulose, is first synthesized from plant fibers or generated from bacteria, fungi, or animals. The natural chemistry of cellulose and its derivatives in the fabrication of hydrogels is briefly discussed. Thereafter, the current scenario and latest developments of cellulose-based conductive hydrogels for tissue engineering are reviewed with an illustration from the literature. Finally, the pro and cons of conductive hydrogels for tissue engineering are indicated.

Functionalization and Antibacterial Applications of Cellulose-Based Composite Hydrogels.

Pathogens, especially drug-resistant pathogens caused by the abuse of antibiotics, have become a major threat to human health and public health safety. The exploitation and application of new antibacterial agents is extremely urgent. As a natural biopolymer, cellulose has recently attracted much attention due to its excellent hydrophilicity, economy, biocompatibility, and biodegradability. In particular, the preparation of cellulose-based hydrogels with excellent structure and properties from cellulose and its derivatives has received increasing attention thanks to the existence of abundant hydrophilic functional groups (such as hydroxyl, carboxy, and aldehyde groups) within cellulose and its derivatives. The cellulose-based hydrogels have broad application prospects in antibacterial-related biomedical fields. The latest advances of preparation and antibacterial application of cellulose-based hydrogels has been reviewed, with a focus on the antibacterial applications of composite hydrogels formed from cellulose and metal nanoparticles; metal oxide nanoparticles; antibiotics; polymers; and plant extracts. In addition, the antibacterial mechanism and antibacterial characteristics of different cellulose-based antibacterial hydrogels were also summarized. Furthermore, the prospects and challenges of cellulose-based antibacterial hydrogels in biomedical applications were also discussed.

Carboxymethyl cellulose-based hydrogel film combined with berberine as an innovative tool for chronic wound management

Polysaccharide-based hydrogels are achieving remarkable performances in chronic wounds treatment. In this work, a carboxymethyl cellulose-based hydrogel film was developed to support skin repair. The hydrogel was loaded with berberine, a polyphenolic molecule endowing antioxidant and cytoprotective features. The film was physico-chemically characterized and in vitro tested on keratinocytes and fibroblasts subjected to oxidative stress. The biocomposite showed high thermal stability (onset decomposition temperature 245 °C) and significant fluid uptake performances, both in free conditions (up to 6510%) and under external pressure (up to 3400%). Moreover, it was able to control oxidative stress and inflammation markers involved in wound chronicity. Keratinocytes hyperproliferation, features that normally hamper injury restoration, was reduced of 25%. Our results showed that the combination of berberine and hydrogel provides a synergic improvement of the material properties. The biocomposite represents a promising candidate for dermatological applications against oxidative stress at the chronic wound site, promoting the healing process.

Insights into the Gelation Mechanism of Metal-Coordinated Hydrogels by Paramagnetic NMR Spectroscopy and Molecular Dynamics

Metal-coordination complexes are attracting increasing attention as supramolecular cross-linkers to develop polymeric hydrogel networks with tunable and dynamic mechanical properties. Nonetheless, the rational design of these materials is still hindered by the limited mechanistic understanding of how metal–ligand interactions influence the structure and properties of the hydrogel. Here, we report a detailed mechanistic investigation using nuclear magnetic resonance (NMR) spectroscopy combined with molecular dynamics (MD) simulations to explore the formation of cellulose-based hydrogels induced by coordination with paramagnetic Fe3+ ions. We demonstrate how NMR paramagnetic relaxation enhancement can be used to probe the distances between the metal center and NMR active nuclei on the polymer chain, informing on the metal–ligand coordination network. Experimental results, together with supporting MD simulations, allow us to uncover a structuration of water around the cross-linked metals within the hydrogel, in addition to the establishment of different orientations of the chains governed by hydrogen bonds networks. Progress in understanding the gelation mechanism of metal-coordinated hydrogels will fuel their exploitation for a wide variety of biomedical applications.

Injectable self-healing cellulose hydrogel based on host-guest interactions and acylhydrazone bonds for sustained cancer therapy

Tumor local chemotherapy employing injectable hydrogel reservoirs is a promising platform to achieve precise drug administration. However, balanced injectability, pH-responsiveness and long-term hydrolysis resistance of self-healing hydrogels remain appealing challenges. Herein, a modular preassembly strategy combining host-guest interactions with dynamic acylhydrazone bonds, was exploited to fabricate injectable cellulose-based hydrogels (CAAs) dressed with self-healing properties, pH-responsiveness and hydrolytic degradation resistance. Attributed to the host-guest interaction between β-cyclodextrin (CD) and 1-adamantane (AD), the hydrogels exhibited injectability, self-healing properties (healing efficiency of 97.5%) and rapid recovery (< 10 min) without external stimuli in physiological environment. Moreover, the hydrogels equipped with dynamic acylhydrazone linkages underwent slow hydrolytic degradation (> 30 days) and pH-responsive behavior, endowing the hydrogels with precise spatiotemporal drug release administration. The in vivo application of CAA as a carrier was studied using doxorubicin (DOX) model drug, and the results shows that using CAA as DOX carrier not only greatly enhances the anti-tumor efficacy of DOX, but also reduced the side effects of DOX. Statement of significanceWith the preassemble approach combining host-guest interactions with dynamic acylhydrazone bonds, this work demonstrated a multi-functional self-healing hydrogel as drug carrier developed by using natural polysaccharides, which offers a new avenue for the high-value utilization of biomass. The strategy demonstrated in the present work may also supply a pathway for the preparation and regulation of hydrogels as intelligent biomedicine materials.

A flexible, robust cellulose/phytic acid/polyaniline hydrogel for all-in-one supercapacitors and strain sensors

An easy handing method was designed to prepare a cellulose-based conductive hydrogel for high performance all-in-one supercapacitors and highly sensitive strain sensors.

Analysis of Bagasse Cellulose-Based Hydrogel for Methylene Blue Removal from Textile Industry Wastewater

Analysis of Bagasse Cellulose-Based Hydrogel for Methylene Blue Removal from Textile Industry Wastewater

Merkezi Bir Kompozit Tasarım Kullanılarak Karboksimetil Selüloz Temelli Hidrojelin Şişme Oranının Belirlenmesi

Bu çalışmada, çapraz bağlayıcı olarak sitrik asit kullanılarak karboksimetil selüloz temelli hidrojel sentezlenmesi ve su tutma kabiliyetinin değerlendirilmesi amaçlanmıştır. Maksimum su emme kapasitesine sahip hidrojelin sentezi için en uygun miktarları belirlemek ve hidrojelin sentezinde yer alan faktörlerin ana etkisini ve etkileşim etkisini incelemek için merkezi kompozit tasarım metodu kullanılmıştır. Polimer bileşimi, sodyum karboksimetil selüloz, sitrik asit ve polietilen glikol 6000/10000 konsantrasyonu (%w/v) gibi ana faktörlerin şişme hızı üzerindeki etkisi değerlendirilmiştir. Ürün bileşeninin optimizasyonu ve tüm verilerin istatistiksel olarak değerlendirilmesi Minitab 17 İstatistik Yazılımı programı ile yapılmıştır. Elde edilen sonuçlar değerlendirildiğinde süper emici hidrojelin optimum koşullar altında üretildiğini göstermiştir.

Synthesis of a Cellulose-Co-AMPS Hydrogel for Personal Hygiene Applications Using Cellulose Extracted from Corncobs.

Cellulose-based hydrogels were prepared by the extraction of cellulose from corncobs after the removal of lignin and hemicellulose with the use of alkali–acid treatment. Acrylate-based hydrogels presently available for personal hygiene uses are not biodegradable. In this study, a biodegradable cellulose-co-AMPS personal hygiene hydrogel was synthesized. The hydrogel was synthesized by graft co-polymerization of 2-acrylamido2-methyl propane sulfonic acid onto corncob cellulose by using potassium persulfate (KPS) as an initiator and borax decahydrate (Na2B4O7·10H2O) as a cross-linking agent. Structural and functional characteristics of the hydrogel such as swelling measurements, antimicrobial tests, FTIR spectra and thermogravimetric analysis were done. The hydrogel showed an average swelling ratio of 279.6 g/g to water and 83.3 g/g to a urine solution with a 97% gel fraction. The hydrogel displayed no clear inhibition zone and did not support the growth of bacteria, Gram-positive or -negative. The FT-IR spectra of the hydrogel confirmed the grafting of an AMPS co-polymer onto cellulose chains. The thermal properties of the hydrogel showed three-step degradation, with a complete degradation temperature of 575 °C.

Optimization of Cellulose-Based Hydrogel Synthesis Using Response Surface Methodology

Synthesis parameters have a significant effect on the properties of cellulose hydrogel. This study aimed to investigate the effects of synthesis parameters, e.g., the cellulose and crosslinkers concentration, on the hydrogels' swelling ratio under both heating and freezing gelation conditions, respectively. Cellulose hydrogels were prepared from wastepaper by the chemical crosslinking method by using epichlorohydrin ECH as a crosslinker. The effects of the synthesis parameters were compared and optimized by response surface methodology (RSM). Synthesized cellulose-based hydrogels under optimized conditions demonstrated an excellent swelling ratio of around 2800%. The optimum swelling ratio of 2467.72% was achieved from the experiment under the heating gelation condition. Thus the synthesized cellulose hydrogels are promising water-saving materials or controlled-release fertilizer carriers for sustainable horticultural and agricultural applications.

The Application Status of Nanoscale Cellulose-Based Hydrogels in Tissue Engineering and Regenerative Biomedicine.

As a renewable, biodegradable, and non-toxic material with moderate mechanical and thermal properties, nanocellulose-based hydrogels are receiving immense consideration for various biomedical applications. With the unique properties of excellent skeletal structure (hydrophilic functional groups) and micro-nano size (small size effect), nanocellulose can maintain the three-dimensional structure of the hydrogel to a large extent, providing mechanical strength while ensuring the moisture content. Owing to its unique features, nanocellulose-based hydrogels have made excellent progress in research and development on tissue engineering, drug carriers, wound dressings, development of synthetic organs, 3D printing, and biosensing. This review provides an overview of the synthesis of different types of nanocellulose, including cellulose nanocrystals, cellulose nanofibers, and bacterial nanocellulose, and describes their unique features. It further provides an updated knowledge of the development of nanocellulose-based functional biomaterials for various biomedical applications. Finally, it discusses the future perspective of nanocellulose-based research for its advanced biomedical applications.

Biomimetic cellulose-based superabsorbent hydrogels for treating obesity

In the treatment of obesity, nutritional and behavioral modifications are difficult to implement and maintain. Since vegetable consumption is a fundamental part of many dietary interventions and daily nutrient requirements, we developed a novel cellulose-based superabsorbent hydrogel (CB-SAH) platform, inspired by the composition and mechanical properties of raw vegetables, as a mechanobiological therapy. The CB-SAHs properties were studied in a simulated gastrointestinal environment, while their impact on gut tissue was investigated by an ex vivo organ culture (EVOC) model. Functional fibers and raw vegetables were used as reference. CB-SAHs demonstrated orders of magnitude higher elasticity in comparison to the tested functional fibers, however performed similar to the tested raw vegetables. Notably, the biomimetic CB-SAHs with elasticity levels similar to raw vegetables showed benefits in preserving and regulating the gut tissue in the EVOC model. Non-systemic oral mechanotherapeutics based on this technology were advanced through clinical studies, with a first product cleared as an aid for weight management in the US and Europe.