Bacterial Cellulose Nanocomposites Research Articles

Enhancing Current Density and Specific Capacitance through Tensile TEMPO, Bacterial Cellulose and Polypirrole Nanocomposites

The researchers developed a bio-composite film material that serves as a substitute for metal. The materials used are TEMPO ((2,2,6,6-tetramethylpiperidine-1-oxyl)), Bacterial Cellulose, and Polypyrrole (Ppy). This research aimed to increase the material's current density and specific capacitance values using the drawing method. Composite nanomaterials are made by oxidizing BC (Bacterial Cellulose) with TEMPO. The resulting TOBC (TEMPO Bacterial Cellulose) material was mixed with Ppy using the in situ method. The mixture is then drawn wet—measurement of current density and capacitance using Cyclic Voltammetry (CV) Testing. The current density and specific capacitance results increased by 542.74% and 754.79% after drawing the nanocomposite material. It is directly proportional to the effects of characteristic testing, which includes SEM, XRD, and FTIR. As a result of the withdrawal of the polypyrrole, it will be more evenly distributed in the composite material, absorbing and coating the nata de coco. The researchers concluded that when the TOBC/Ppy fibers are straighter and denser, they achieve higher current density and capacitance values.

Addition of Graphene on the Bacterial Cellulose Nanocomposite Membrane with Copper Oxide Reinforcement

Addition of Graphene on the Bacterial Cellulose Nanocomposite Membrane with Copper Oxide Reinforcement

Synthesis and Characterization of Bacterial Cellulose‐Curcumin‐Ag‐Se Nanocomposites having Antioxidant and Antibacterial properties for Skin Healing Applications

AbstractBacterial Cellulose is a polymer synthesised by some strains of bacteria thus perceived as environmentally friendly. Bacterial Cellulose (BC) was subjected to three different drying procedures; Freeze Drying, Blot drying and Oven drying. Studies on its water holding capacity, thermogravimetric analysis and mechanical strength revealed that Freeze drying was the best method for retaining its pore size and water holding capacity. Silver selenium nanoparticles complexed with Curcumin (Cur‐AgSeNPs) were loaded on BC and characterised by FESEM, EDX, FTIR and XRD. The ultrastructure of the BC nanocomposite revealed a three‐dimensional network of interwoven cellulose microfibrils with the nanoparticle complex adsorbed onto the surface as well as embedded within the porous structure of the membrane. Antimicrobial analysis of the BCnanocomposite showed bactericidal activity against P. aeruginosa (MTCC 741), E. coli (MTCC 2574) and S. aureus (MTCC 737) cultures. 0.5 mM Cur‐AgSeNPs loaded BC film showed a Radical Scavenging Activity of 63.92±0.76 % by ABTS assay and a cell viability of 75 % after 4 days for L929 fibroblast cells. Haemocompatibility test of the films showed <10 % haemolysis of RBCs indicating their haemocompatible nature. These results suggest that the BCnanocomposite film would open up the possibility for use as an ideal skin healing material.

Investigation of physicochemical and biological properties of bacterial cellulose & zein-reinforced edible nanocomposites based on flaxseed mucilage containing Origanum vulgare L. essential oil

In the present study, the effect of zein and different amounts of bacterial cellulose (BC; 1, 2 and 3 wt%) on the physical, mechanical and barrier properties of flaxseed mucilage/carboxymethyl cellulose (FM/CMC) composite was investigated. The appearance of the absorption band at 1320cm−1 in the ATR-FTIR spectra of nanocomposites indicated the successful introduction of zein into their structure. The characteristic peak at 2θ of 9° belonging to zein disappeared in XRD patterns of the prepared composites suggesting the successful coating of zein via hydrogen bonding interactions. SEM images proved the formation of semi-spherical zein microparticles in the FM/CMC matrix. TGA plots ascertained the addition of zein and nanocellulose caused a significant increase in the thermal stability of FM/CMC film, although zein showed a greater effect. The presence of zein and nanocellulose increased the mechanical strength of nanocomposites. The WVP of FM/CMC decreased after the incorporation of zein and nanocellulose, which created a tortuous path for the diffusion of water molecules. The zein particles exhibited a greater influence on improving the mechanical and barrier properties compared to nanocellulose. FM/CMC-Z film exhibited the highest mechanical strength (49.07 ± 5.89 MPa) and the lowest WVP (1.179 ± 0.076). The composites containing oregano essential oil (EO) showed higher than 60 % antibacterial properties. The bactericidal efficiency of FM/CMC/Z-EO and FM/CMC/Z-EO/BC1 nanocomposites decreased about 10% compared to FM/CMC/EO and FM/CMC-Z/BC1. This evidenced the successful encapsulation of EO molecules in zein particles. According to the in vitro release study, entrapment of EO into zein particles could delay the release and provide the extended antimicrobial effect.

Silver phosphate–bacterial cellulose nanocomposites as visible light photocatalyst for wastewater purification

Silver phosphate (Ag3PO4) nanoparticles were deposited on bacterial cellulose (BC) nanofibrils as an eco-friendly, efficient, and reusable visible light active photocatalyst. BC–Ag3PO4 nanocomposites (BCAgP) with different BC/Ag3PO4 weight ratios were prepared by solution-precipitation method. The nanocomposites were characterized by UV-Visible diffuse reflection spectroscopy, XRD, FTIR, BET, and FESEM. Highly crystalline Ag3PO4 nanoparticles were well entrapped inside nano fibrillated BC matrix and eventually deposited along the fibers. Photocatalytic activity of the BCAgP nanocomposites were investigated by dye degradation experiments under solar light. The composite with BC: Ag3PO4 weight ratio of 1:4 (BCAgP14) showed the highest photocatalytic efficiency compared to other weight ratios and pure Ag3PO4. The sample also shows good photocatalytic activity even after 4 runs indicating its photostability. Higher photocatalytic efficiency of BCAgP14 nanocomposite was explained due to optimum Ag3PO4 loading and higher visible light absorption capacity. Bacterial cellulose is supposed to improve the photocatalytic activity of silver phosphate by promoting the adsorption of dyes and extending the charge recombination time under visible light of Ag3PO4 photocatalyst.

An advanced oxidized bacterial cellulose platform for improving the photocatalysis performance of BiOCl

Herein, we present a high-performance flower-like BiOCl-oxidized bacterial cellulose (BiOCl-OBC) nanocomposites were designed and developed employing sustainable bacterial cellulose (BC) as regulator through a simple hydrothermal synthesis method. OBC has abundant hydroxide ions, and Bi3+ is entangled and dispersed in OBC solution, which promotes the in-situ growth of BiOCl nanosheets on OBC fiber network, forming BiOCL-OBC composite materials similar to flowers and changing their surface properties. Due to the negatively charged of BiOCl-OBC composites, the Rhodamine B (RhB) cationic dye was easily to adsorbed to its surface, which facilitates the occurrence of photosensitization and photocatalysis in the reaction. BiOCl-OBC composites exhibited high photocatalytic degradation performance for RhB under multi-mode illumination conditions; the cycle test results show that the BiOCl-OBC composite has good stability and recyclability. Finally, the photocatalytic degradation mechanism of BiOCl-OBC composites was discussed. Therefore, the OBC is expected to be used as a modifier for the surface modification to improve the photocatalytic performance of BiOCl and the BiOCl-OBC nanocomposite is a novel promising candidate as adsorbent photocatalysts with visible illumination reaction.

Polydopamine-Functionalized Bacterial Cellulose as Hydrogel Scaffolds for Skin Tissue Engineering.

Bacterial cellulose (BC) is a natural polysaccharide polymer hydrogel produced sustainably by the strain Gluconacetobacter hansenii under static conditions. Due to their biocompatibility, easy functionalization, and necessary physicochemical and mechanical properties, BC nanocomposites are attracting interest in therapeutic applications. In this study, we functionalized BC hydrogel with polydopamine (PDA) without toxic crosslinkers and used it in skin tissue engineering. The BC nanofibers in the hydrogel had a thickness of 77.8 ± 20.3 nm, and they could be used to produce hydrophilic, adhesive, and cytocompatible composite biomaterials for skin tissue engineering applications using PDA. Characterization techniques, namely Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and Raman spectroscopy, were performed to investigate the formation of polydopamine on the BC nanofibers. The XRD peaks for BC occur at 2θ = 14.65°, 16.69°, and 22.39°, which correspond to the planes of (100), (010), and (110) of cellulose type Iα. Raman spectroscopy confirmed the formation of PDA, as indicated by the presence of bands corresponding to the vibration of aromatic rings and aliphatic C-C and C-O stretching at 1336 and 1567 cm-1, respectively. FTIR confirmed the presence of peaks corresponding to PDA and BC in the BC/PDA hydrogel scaffolds at 3673, 3348, 2900, and 1052 cm-1, indicating the successful interaction of PDA with BC nanofibers, which was further corroborated by the SEM images. The tensile strength, swelling ratio, degradation, and surface wettability characteristics of the composite BC biomaterials were also investigated. The BC/PDA hydrogels with PDA-functionalized BC nanofibers demonstrated excellent tensile strength and water-wetting ability while maintaining the stability of the BC fibers. The enhanced cytocompatibility of the BC/PDA hydrogels was studied using the PrestoBlue assay. Culturing murine NIH/3T3 fibroblasts on BC/PDA hydrogels showed higher metabolic activity and enhanced proliferation. Additionally, it improved cell viability when using BC/PDA hydrogels. Thus, these BC/PDA composite biomaterials can be used as biocompatible natural alternatives to synthetic substitutes for skin tissue engineering and wound-dressing applications.

Bacterial cellulose: A highly versatile nanomaterial.

Bacterial cellulose: A highly versatile nanomaterial.

Preparation and performance of bacterial cellulose-based enzyme-carrying composite hydrogels as wound healing material

As a biosynthetic polymer, Bacterial cellulose (BC) has been largely used in biomedical and technological fields for the excellent biocompatibility and water holding capability. In this study, BC hydrogel were mass-produced from G. xylinus. A novel gel, BC nanocomposite (BC/NC) hydrogel, was prepared via in situ free radical aqueous polymerization from NIPAM in the presence of Clay was added as physical crosslinker. The physical and chemical properties were evaluated, and the results showed that the properties of the composite hydrogel were improved, for example, the Young’s modulus rose by nearly 30%, from 4.7 to 6.0 Mpa with the increasing of NIPAM. BC/NC-lys hydrogel were prepared by treating BC/NC hydrogel with Lysostaphin solution, and the cytocompatibility and antibacterial activities were assessed in vitro. The effects of composite hydrogel on wound healing were examined in rat skin models, the cure rate was up to 92.35% in the test group and only 78.83% in the control group after 14 days. The composite BC/NC3-lys hydrogel were developed in the hope of accelerating the wound healing process as well as decreasing the infection rate.

Pyrolyzed Bacterial Cellulose as the Backbone of the Cathode Catalyst-CoFe2O4 for the Li-O2 Battery

In this paper, CoFe2O4@pyrolyzed bacterial cellulose (CFO@PBC) nanocomposites were synthesized by a hydrothermal process and an in situ composite technique as the cathode for rechargeable Li-O2 batteries (LOB). CoFe2O4@Ketjenblack (CFO@KB) were prepared in the same way as the comparison. The as-prepared materials were characterized by SEM, XRD, and BET. The LOB with CFO@PBC-3 showed a maximum initial discharge capacity of 2660 mAh g−1 (electrode) at the current density of 100 mAg−1, while the mass ratio of CoFe2O4 and pyrolyzed bacterial cellulose was 3. The cyclic voltammetry of the CFO@PBC nanocomposite electrodes was investigated at 0.1 mVs−1 in the voltage window of 2.0–4.5 V. With the limited capacity of 640 mAh g−1 (electrode), the CFO@PBC-3 electrode showed the best cycle stability and higher cutoff voltage of discharging. The pyrolyzed bacterial cellulose, as the fibrous 3D backbone in CFO@PBC nanocomposite electrodes, produced better results than the CFO@KB.

Effects of pullulan additive and co-culture of Aureobasidium pullulans on bacterial cellulose produced by Komagataeibacter hansenii.

Bacterial cellulose (BC) exhibits a unique combination of porosity, tensile strength, reticulated crystal structure and biocompatibility useful for many applications in the food, biomedical and other industries. Polysaccharide addition has been shown to improve the production and the mechanical properties of BC nanocomposites. This study examined the effect of pullulan on BC fermentation as well as the co-culturing of the BC producer with Aureobasidium pullulans, a fungal strain that produces pullulan as an exopolysaccharide. Results showed that a 1% pullulan addition improved Young's modulus of BC pellicles for sixfold. Addition of pullulan at 1.5% and 2% levels could increase the BC production from 0.447 to 0.814 and 1.997g/L, respectively. The co-culture fermentation demonstrated a mixed effect on the aggregation and bundling of BC while resulting in a significant improvement in mechanical properties. The study provided a polysaccharide additive and a novel fermentation method to produce BC with improved properties.

Efficient Catalytic Degradation of Phenol with Phthalocyanine-Immobilized Reduced Graphene-Bacterial Cellulose Nanocomposite.

In this report, phthalocyanine (Pc)/reduced graphene (rG)/bacterial cellulose (BC) ternary nanocomposite, Pc-rGBC, was developed through the immobilization of Pc onto a reduced graphene–bacterial cellulose (rGBC) nanohybrid after the reduction of biosynthesized graphene oxide-bacterial cellulose (GOBC) with N2H4. Field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FT-IR) were employed to monitor all of the functionalization processes. The Pc-rGBC nanocomposite was applied for the treatment of phenol wastewater. Thanks to the synergistic effect of BC and rG, Pc-rGBC had good adsorption capacity to phenol molecules, and the equilibrium adsorption data fitted well with the Freundlich model. When H2O2 was presented as an oxidant, phenol could rapidly be catalytically decomposed by the Pc-rGBC nanocomposite; the phenol degradation ratio was more than 90% within 90 min of catalytic oxidation, and the recycling experiment showed that the Pc-rGBC nanocomposite had excellent recycling performance in the consecutive treatment of phenol wastewater. The HPLC result showed that several organic acids, such as oxalic acid, maleic acid, fumaric acid, glutaric acid, and adipic acid, were formed during the reaction. The chemical oxygen demand (COD) result indicated that the formed organic acids could be further mineralized to CO2 and H2O, and the mineralization ratio was more than 80% when the catalytic reaction time was prolonged to 4 h. This work is of vital importance, in terms of both academic research and industrial practice, to the design of Pc-based functional materials and their application in environmental purification.

Hard magnetic membrane based on bacterial cellulose – Barium ferrite nanocomposites

Magnetic membranes based on bacterial cellulose (BC) nanocomposites have been extensively researched. However, most magnetic nanoparticles (NPs) incorporated in the BC matrix were focused on soft magnetic phases, which limited the extensive use of magnetic BC membranes. Therefore, this work proposes a method to fabricate hard magnetic membrane based on the BC matrix and magnetically hard phase barium ferrite (BFO) NPs. The nanocomposites showed the peaked tensile strength and modulus at the low concentration of BFO whereas the magnetization increased drastically with the BFO content. They also demonstrate the high flexibility up on bending and the sensitivity to external magnetic fields. Furthermore, unlike other magnetic BC membranes, the BC/BFO nanocomposites exhibited the hard magnetic properties, i.e. they could retain their magnetic attraction after being magnetized by a permanent magnet. These properties open the possibility to employ these materials in various fields, such as information storage, anti-couterfeit or electromagnetic shieldings.

Recent development in bacterial cellulose production and synthesis of cellulose based conductive polymer nanocomposites

AbstractCompared to plant‐based cellulosic biopolymers, bacterial cellulose (BC) produced from microbial sources demonstrates several unique properties. BC nanocomposites synthesized with the addition of nanofillers with distinct properties have further tailored the BC structure with improved physical and chemical properties. BC nanocomposites with the addition of electrically conductive filler materials, namely, conductive polymers, metallic or carbonaceous nanofillers have advanced the nanocomposites applications and their utilization in the fabrication of various modern electrical and electronic appliances such as biosensors, flexible electronics, electromagnetic interference (EMI) shielding and energy storage. The present review is focused to provide a complete overview of BC production and electrically conductive‐based‐BC nanocomposites at a single platform. Various methodologies used in BC production with varying microbial strains and substrate types used in the fermentation, surface functionalization of BC, and its purification are discussed in detail. Subsequently, the review explains the bacterial cellulose‐based electrical conductive nanocomposites combined with different types of nanofillers such as conductive polymers, metal oxides, and carbon‐based nanofillers for their application in modern electronic devices. The challenges faced during nanocomposites synthesis and methods to improve its electrical conductivity with possible futuristic solutions are also briefly discussed.

Silver Decorated Bacterial Cellulose Nanocomposites as Antimicrobial Food Packaging Materials

Silver Decorated Bacterial Cellulose Nanocomposites as Antimicrobial Food Packaging Materials

Co-culture fermentation on the production of bacterial cellulose nanocomposite produced by Komagataeibacter hansenii

Bacterial cellulose (BC11Uncommon abbreviation used: BC – Bacterial Cellulose) is a biomaterial produced by various strains of microorganisms. BC has improved strength and unique structural properties as compared to plant cellulose, thus has many usages in the food and pharmaceutical industries. In our previous study, a novel co-culture agitated fermentation of Komagataeibacter hansenii, a BC producer, with Aureobasidium pullulans, a producer of pullulan polysaccharide, had been demonstrated where the BC produced exhibited improved mechanical properties. Therefore, this study is undertaken to analyze BC production under different medium composition using response surface methodology (RSM) in shake-flasks and benchtop bioreactors. A verified local high point provided 22.4% higher BC production and 4.5- to 6- folds higher elastic moduli in shake-flasks and bioreactors compared to the baseline media. Overall, the study had revealed the potential of the co-culturing method to enhance BC production while maintaining the desired mechanical properties of BC produced in shake-flasks and larger scale bioreactors.

Development of bacterial cellulose nanocomposites: An overview of the synthesis of bacterial cellulose nanocomposites with metallic and metallic-oxide nanoparticles by different methods and techniques for biomedical applications

Bacterial cellulose is the three-dimensional network structure of nanofibers. The bacterial cellulose materials have outstanding characteristics of high surface area and high crystallinity (84%–89%). It has greater compatibility with the degree of polymerization and has excellent mechanical properties. The water-holding capacity of bacterial cellulose (over 100 ti) makes it stand out from other cellulose materials. This is because bacterial cellulose has high purity due to a lack of lignin and hemicellulose. Bacterial cellulose is considered as a non-cytotoxic, non-genotoxic, and highly biocompatible material, which has broad appeal in the medical field and has attracted widespread attention. The proposed review summarizes the microbial effects of enlisting bacterial strains with carbon sources, and culture media on bacterial cellulose production. In addition, it provides a variety of physical and chemical methods that can be used to modify bacterial cellulose with metal and metal oxide nanoparticles; like the common structure of zinc oxide/bacterial cellulose represent antibacterial characteristics against C.freundii, S.aureus, E.coli, and P.aeruginosa with 90.9%, 94.3%, 90.0%, and 87.4% strength respectively. The wound healing properties of such metallic oxide structure with bacterial cellulose presents the characteristics, which confirms its application in 66% of strength, especially for bionic designs for medical applications, including wound healing and artificial skin, vascular and neurosurgical covering materials, dural prosthesis, arterial stent coating, cartilage, bone repair grafts, and biomedicines. Because of the further exposure of value-added medical material application, our review ends with challenges and perspectives in the production of bacterial cellulose nanocomposite.

Electrochemical analysis of specific catalase activity during development of Aspergillus flavus and its correlation with aflatoxin B1 production

Aflatoxin B1 (AFB1) contamination causes huge economic losses. To explore the correlation between catalase (CAT) and AFB1 production during fungal development, we fabricated an electrochemical CAT-activity sensor by measuring residual H2O2 after enzymatic degradation. The sensor made by palladium nanoparticles/carbonized bacterial cellulose nanocomposites exhibits a linear range over 0.5–3.5 U/mL and a detection limit of 0.434 U/mL. Both dry weight and CAT activity of mycelia continuously increase. But, the latter shows a greater increase than the former after three days. Specific CAT activity in crude enzyme extract of A. flavus was quantified. It maintains at ~25.00 U/mg for 3 days and enhances to 28.91 and 45.30 U/mg, respectively, on days 4 and 5. AFB1 production follows the same trend. On days 4 and 5, AFB1 concentration reaches 201.35 and 767.9 ng/mL, respectively. The positive correlation between specific CAT activity and AFB1 production suggests that CAT is involved in AFB1 biosynthesis.

Facile One-Step Fabrication of Phthalocyanine-Graphene-Bacterial-Cellulose Nanocomposite with Superior Catalytic Performance.

It is generally accepted that the convenient fabrication of a metal phthalocyanine-based heterogeneous catalyst with superior catalytic activity is crucial for its application. Herein, a novel and versatile ultrasonic-assisted biosynthesis approach (conducting ultrasonic treatment during biosynthesis process) was tactfully adopted for the direct immobilization of a sulfonated cobalt phthalocyanine (PcS) catalyst onto a graphene–bacterial cellulose (GBC) substrate without any modification. The prepared phthalocyanine–graphene–bacterial–cellulose nanocomposite, PcS@GBC, was characterized by field emission scanning electron microscope (FESEM) and X-ray photoelectron spectroscopy (XPS). The catalytic activity of the PcS@GBC was evaluated based on its catalytic oxidation performance to dye solution, with H2O2 used as an oxidant. More than a 140% increase of dye removal percentage for the PcS@GBC heterogeneous catalyst was found compared with that of PcS. The unique hierarchical architecture of the GBC substrate and the strong interaction between PcS and graphene, which were verified experimentally by ultraviolet-visible light spectroscopy (UV-vis) and Fourier transform infrared spectroscopy (FT-IR) and theoretically by density functional theory (DFT) calculation, were synergistically responsible for the substantial enhancement of catalytic activity. The accelerated formation of the highly reactive hydroxyl radical (·OH) for PcS@GBC was directly evidenced by the electron paramagnetic resonance (EPR) spin-trapping technique. A possible catalytic oxidation mechanism for the PcS@GBC–H2O2 system was illustrated. This work provides a new insight into the design and construction of a highly reactive metal phthalocyanine-based catalyst, and the practical application of this functional nanomaterial in the field of environmental purification is also promising.

Sustainable Wood-Based Hierarchical Solar Steam Generator: A Biomimetic Design with Reduced Vaporization Enthalpy of Water.

Water purification by solar distillation is considered a promising technology for producing clean water from undrinkable water resources. A solar steam generator is a central part of a solar distillation process to separate water and contaminants. Here, we report an efficient and sustainable hierarchical solar steam generator (HSSG) with reduced vaporization enthalpy based on bacterial cellulose (BC) nanocomposites. The nanomaterials are assembled with BC nanofibers produced by bacteria in situ to form nanocomposites. Using this method, we construct functional BC nanocomposites inside and on the natural porous structure of wood. Our HSSG integrates solar-to-vapor efficiency improvement and vaporization enthalpy reduction by integrating the hierarchical multifunctional BC nanocomposites with the natural porous structure of wood. Because of the biomimetic design, hierarchical structure and reduced vaporization enthalpy of HSSG, a high evaporation rate of 2.9 kg m-2 h-1 and solar-to-vapor efficiency of 80% is achieved.