Biocompatible microcrystalline cellulose particles from cotton wool and magnetization via a simple in situ co-precipitation method

Physico-chemical and antifungal studies of spun cotton thread reinforced cellulose film

This study examines cellulose films reinforced with spun cotton thread and their antifungal properties. The morphology and structure of the cellulose film are analyzed using various techniques, including X-ray Diffraction (XRD), Fourier Transform Infrared (FT-IR) Spectroscopy, Field Emission Scanning Electron Microscope (FE-SEM), Atomic Force Microscope (AFM), UV-Visible Spectroscopy (UV-Vis), Thermogravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC). The XRD pattern confirms the crystalline nature of the spun cotton-reinforced cellulose film. UV absorption analysis shows activity in the UV region of the optical spectrum. The reinforced cellulose film shows a band gap of 4.7 eV by employing the Wood and Tauc equation. FTIR spectroscopy confirms the film's structural formation. Morphological analysis reveals a random distribution of numerous pore structures on the material's surface. Thermalgravimetric Analysis indicates the material's stability at elevated temperatures, suggesting versatile applications. The film also exhibits antifungal activity against Candida albicans. This research highlights the potential of reinforced cellulose film in various applications, such as food and non-food packaging, offering enhanced UV protection and strength for heavy goods transport. The study emphasizes the multifunctional properties of the material, showcasing its promising role as a polymer in various practical applications.

Microwave-assisted quick synthesis of microcrystalline cellulose from black tea waste (Camellia sinensis) and characterization

Tea wastes generated in the industries during tea production processes show excellent potential to be used as a renewable, abundant, and cheap source for the extraction of microcrystalline cellulose. In the current work, MCC was isolated from black tea waste through microwave heating instead of using conventional heating and avoiding the traditional acid hydrolysis method. Microwave increased the reaction speed significantly and resulted in very quick delignification and bleaching of black tea waste to isolate MCC in white powdered form. FTIR, XRD, FESEM, and TGA analysis were then carried out to investigate the chemical functionality, crystallinity, morphology, and thermal properties, respectively, of the synthesized tea waste MCC. The characterization results demonstrated that cellulose with a short rough fibrous structure having an average particle size of around 23 μm was extracted. The results of FTIR and XRD demonstrated unequivocally that all amorphous non-cellulosic compounds had been eliminated. The microwave-extracted black tea waste MCC showed 89.77 % crystallinity and good thermal properties, indicating that it could be a promising filler material for preparing polymer composites. Therefore, microwave-assisted delignification and bleaching can be used as a suitable, energy-efficient, time-saving and low-cost method for extracting MCC from the black tea waste produced in tea factories.

Synthesis of Magnetic Iron Oxide-Incorporated Cellulose Composite Particles: An Investigation on Antioxidant Properties and Drug Delivery Applications

In recent years, polymer-supported magnetic iron oxide nanoparticles (MIO-NPs) have gained a lot of attention in biomedical and healthcare applications due to their unique magnetic properties, low toxicity, cost-effectiveness, biocompatibility, and biodegradability. In this study, waste tissue papers (WTP) and sugarcane bagasse (SCB) were utilized to prepare magnetic iron oxide (MIO)-incorporated WTP/MIO and SCB/MIO nanocomposite particles (NCPs) based on in situ co-precipitation methods, and they were characterized using advanced spectroscopic techniques. In addition, their anti-oxidant and drug-delivery properties were investigated. Field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) analyses revealed that the shapes of the MIO-NPs, SCB/MIO-NCPs, and WTP/MIO-NCPs were agglomerated and irregularly spherical with a crystallite size of 12.38 nm, 10.85 nm, and 11.47 nm, respectively. Vibrational sample magnetometry (VSM) analysis showed that both the NPs and the NCPs were paramagnetic. The free radical scavenging assay ascertained that the WTP/MIO-NCPs, SCB/MIO-NCPs, and MIO-NPs exhibited almost negligible antioxidant activity in comparison to ascorbic acid. The swelling capacities of the SCB/MIO-NCPs and WTP/MIO-NCPs were 155.0% and 159.5%, respectively, which were much higher than the swelling efficiencies of cellulose-SCB (58.3%) and cellulose-WTP (61.6%). The order of metronidazole drug loading after 3 days was: cellulose-SCB < cellulose-WTP < MIO-NPs < SCB/MIO-NCPs < WTP/MIO-NCPs, whereas the sequence of the drug-releasing rate after 240 min was: WTP/MIO-NCPs < SCB/MIO-NCPs < MIO-NPs < cellulose-WTP < cellulose-SCB. Overall, the results of this study showed that the incorporation of MIO-NPs in the cellulose matrix increased the swelling capacity, drug-loading capacity, and drug-releasing time. Therefore, cellulose/MIO-NCPs obtained from waste materials such as SCB and WTP can be used as a potential vehicle for medical applications, especially in a metronidazole drug delivery system.

Preparation of Spherical Cellulose Nanocrystals from Microcrystalline Cellulose by Mixed Acid Hydrolysis with Different Pretreatment Routes

Spherical cellulose nanocrystal (CNC), as a high value cellulose derivative, shows an excellent application potential in biomedicine, food packaging, energy storage, and many other fields due to its special structure. CNC is usually prepared by the mixed acid hydrolysis method from numerous cellulose raw materials. However, the pretreatment route in preparing spherical CNC from cellulose fiber is still used when choosing microcrystalline cellulose (MCC) as the raw material, which is not rigorous and economical. In this work, pretreatment effects on the properties of spherical CNC produced from MCC by mixed acid hydrolysis were systematically studied. Firstly, the necessity of the swelling process in pretreatment was examined. Secondly, the form effects of pretreated MCC (slurry or powder form) before acid hydrolysis in the preparation of spherical CNC were carefully investigated. The results show that the swelling process is not indispensable. Furthermore, the form of pretreated MCC also has a certain influence on the morphology, crystallinity, and thermal stability of spherical CNC. Thus, spherical CNC with different properties can be economically prepared from MCC by selecting different pretreatment routes through mixed acid hydrolysis.

Cellulose Structures as a Support or Template for Inorganic Nanostructures and Their Assemblies

Cellulose is the most abundant natural polymer and deserves the special attention of the scientific community because it represents a sustainable source of carbon and plays an important role as a sustainable energent for replacing crude oil, coal, and natural gas in the future. Intense research and studies over the past few decades on cellulose structures have mainly focused on cellulose as a biomass for exploitation as an alternative energent or as a reinforcing material in polymer matrices. However, studies on cellulose structures have revealed more diverse potential applications by exploiting the functionalities of cellulose such as biomedical materials, biomimetic optical materials, bio-inspired mechanically adaptive materials, selective nanostructured membranes, and as a growth template for inorganic nanostructures. This article comprehensively reviews the potential of cellulose structures as a support, biotemplate, and growing vector in the formation of various complex hybrid hierarchical inorganic nanostructures with a wide scope of applications. We focus on the preparation of inorganic nanostructures by exploiting the unique properties and performances of cellulose structures. The advantages, physicochemical properties, and chemical modifications of the cellulose structures are comparatively discussed from the aspect of materials development and processing. Finally, the perspective and potential applications of cellulose-based bioinspired hierarchical functional nanomaterials in the future are outlined.

Positively-charged microcrystalline cellulose microparticles: Rapid killing effect on bacteria, trapping behavior and excellent elimination efficiency of biofilm matrix from water environment

Pathogen and biofilm contamination in aqueous systems leave millions of people at risk of waterborne diseases. Herein, to address this issue, a green and highly efficient strategy is developed to concurrently trap and kill bacteria, eliminate the debris and the existing biofilm matrix in water environment via magnetic microparticles. The particles (TPFPs) were prepared from the in-situ deposition of Fe₃O₄ nanoparticles onto the surface of antibacterial functionalized microcrystalline cellulose (MCC). Noticeably, TPFPs can completely inactivate both S. aureus and E. coli once contacting for 30 min by disrupting the bacterial membrane. Meanwhile, the MCC-based magnetic particles retained 100% biocidal efficiency against E. coli (5 * 10⁴E. coli/mg particles) during ten recycling procedures without any treatment. More importantly, according to the results of trapping behavior and antibiofilm assays, not only bacteria could be captured by the particles (trapping rate was over 85%), but also the residual debris from dead bacteria and fragmented biofilm was together removed based on the special structure and functions of the antibacterial particles (~ 80%), including extremely rough surfaces, surficial positive charge and magneto-responsive property. This study presents an efficient approach for microorganism management in water system which can be expectantly applied to improve the water safety.

A critical review on the techniques used for the synthesis and applications of crystalline cellulose derived from agricultural wastes and forest residues

In order to meet the growing energy crisis of the 21st century, the utilization of bio-based materials has become a field of high research endeavour. In view of that, the present review paper is focused on different techniques that are frequently explored for the synthesis of value-added crystalline derivatives of cellulose like MCC and NCC from agricultural wastes and forest residues. Moreover, a comparative analysis between thermochemical and biochemical methods is carried out for such valorization of biomass considering the mechanism involved with various reactions. Further, a critical analysis is performed on various individual techniques specifically used for the applications of MCC and NCC in different fields including environmental, polymer industry, pharmaceutical and other emerging sectors. This article will assist the readers not only to explore new biomass sources but also provides an in-depth insight on various green and cost-effective methods for sustainable production of crystalline cellulose.

Structural characterization of microcrystalline and nanocrystalline cellulose from Ananas comosus L. leaves: Cytocompatibility and molecular docking studies

The present study focused on the preparation of microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC) from pineapple (Ananas comosus L.) leaves using chemical treatments followed by acid hydrolysis. Pineapple leaves could be used in medical applications such as drug delivery carriers. Advanced spectroscopy techniques such as Fourier-transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to analyze the physical, chemical, and morphological features of the isolated MCC and NCC; the results indicated the needle-shaped form of nanostructures with good purity and high crystallinity index of 75.00 and 76.38%, respectively. In addition, inhibition of the treated MRC-5 cells with all the samples revealed that the percentage of cell viability was less than 30%, which is an interesting finding given their role in the cytotoxicity effect of MCC and NCC. It appears that MCC and NCC derived from pineapple leaves have lower toxicity. As a result, the developed MCC and NCC can be used in pharmaceutical applications as a novel drug delivery system. Molecular docking was performed to understand the non-bonding interaction of cellulose with human acid-beta-glucosidase (β-Glc) (PDB: 1OGS). The docking result shows that cellulose unit docked within the active pocket of the enzyme by forming hydrogen bonds against ASN19, THR21, and VAL17 with distances of 2.18, 1.93, and 2.92 Å, respectively, with binding energy (−5.0 kcal/mol) resulting in close interaction of cellulose unit with the receptor.

Preparation, characterization and its potential applications in Isoniazid drug delivery of porous microcrystalline cellulose from banana pseudostem fibers

Banana pseudostem, a cellulose-rich by-product, is regarded as an important agricultural waste during the process of banana production. Microcrystalline cellulose was successfully prepared from banana pseudostem using acid hydrolysis method. Microcrystalline cellulose was characterized through various techniques such as XRD, TGA, SEM, FTIR and antioxidant activity to explore the possible applications in the pharmaceutical industries especially as a drug delivery vehicle. The investigation revealed that the derived microcrystalline cellulose is non-aggregated, short rods with high crystallinity index 67% and stable up to 347 °C. FTIR spectroscopy showed that hydrolysis treatments are efficient for the removal of lignin and hemicellulose content. Microcrystalline cellulose exhibited good antioxidant activity 90.29% at 100 μg/ml. In vitro studies for the drug release were carried out in simulated intestinal fluid (SIF) using Isoniazid drug. The study proves that microcrystalline cellulose can be directly obtained from banana pseudostem which is not only beneficial to reduce the cost of traditional microcrystalline cellulose but is also conducive to the value-added utilization of the pseudostem.

Morphological, Physiochemical and Thermal Properties of Microcrystalline Cellulose (MCC) Extracted from Bamboo Fiber

Bamboo fibers are utilized for the production of various structures, building materials, etc. and is of great significance all over the world especially in southeast Asia. In this study, the extraction of microcrystalline cellulose (MCC) was performed using bamboo fibers through acid hydrolysis and subsequently different characterizations were carried out using various advanced techniques. Fourier transform infrared (FTIR) spectroscopy analysis has indicated the removal of lignin from MCC extracted from bamboo pulp. Scanning Electron Microscopy (SEM) revealed rough surface and minor agglomeration of the MCC. Pure MCC, albeit with small quantities of impurities and residues, was obtained, as revealed by Energy Dispersive X-ray (EDX) analysis. X-ray diffraction (XRD) indicates the increase in crystallinity from 62.5% to 82.6%. Furthermore, the isolated MCC has slightly higher crystallinity compared to commercial available MCC (74%). The results of thermal gravimetric analysis (TGA) demonstrate better thermal stability of isolated MCC compared to its starting material (Bamboo fibers). Thus, the isolated MCC might be used as a reinforcing element for the production of green composites and it can also be utilized as a starting material for the production of crystalline nanocellulose in future.

Synthesis and SERS application of gold and iron oxide functionalized bacterial cellulose nanocrystals (Au@Fe3O4@BCNCs)

Bacterial cellulose nanocrystals (BCNCs) are biocompatible cellulose nanomaterials that can host guest nanoparticles to form hybrid nanocomposites with a wide range of applications. Herein, we report the synthesis of a hybrid nanocomposite that consists of plasmonic gold nanoparticles (AuNPs) and superparamagnetic iron oxide (Fe3O4) nanoparticles supported on BCNCs. As a proof of concept, the hybrid nanocomposites were employed to isolate and detect malachite green isothiocyanate (MGITC) via magnetic separation and surface-enhanced Raman scattering (SERS). Different initial gold precursor (Au3+) concentrations altered the size and morphology of the AuNPs formed on the nanocomposites. The use of 5 and 10 mM Au3+ led to a heterogenous mix of spherical and nanoplate AuNPs with increased SERS enhancements, as compared to the more uniform AuNPs formed using 1 mM Au3+. Rapid and sensitive detection of MGITC at concentrations as low as 10-10 M was achieved. The SERS intensity of the normalized Raman peak at 1175 cm-1 exhibited a log-linear relationship for MGITC concentrations between 2 × 10-10 and 2 × 10-5 M for Au@Fe3O4@BCNCs. These results suggest the potential of these hybrid nanocomposites for application in a broad range of analyte detection strategies.

Microcrystalline cellulose (MCC) based materials as emerging adsorbents for the removal of dyes and heavy metals - A review

In an attempt to overcome such threats posed by water pollution, various processes ranging from physical, chemical as well as biological were applied to get rid of wastewater pollutants. The simplicity, high efficiency and cheapness of an adsorption process make it the most widely used among various other processes. Adsorbents with different properties were used in the adsorption process but this paper was focused on reviewing various articles published by numerous researchers on the isolation of microcrystalline cellulose (MCC), a popular carbohydrate polymer from lignocellulosic biomass and utilization of MCC based materials as effective adsorbents for the successful removal of dyes and heavy metals from synthetic wastewater. The sudden interest on MCC and MCC-based materials as adsorbents cannot be separated from their excellent properties such as renewability, biodegradability, biocompatibility, economic value, non-toxicity, high mechanical properties and surface area. Upon comparison with established adsorbents reported from literature, MCC-based materials performed excellently well in the adsorption of dyes and heavy metals with Langmuir isotherm and pseudo-second order reported mostly as the best fit models for the generated equilibrium and kinetic data, respectively pointing at the distribution of adsorption sites to be homogeneous as well as the formation of monolayer adsorbate on their surfaces. The various thermodynamic studies reported further revealed the adsorption processes of both dyes and heavy metals onto MCC-based materials to be entropy driven processes, spontaneous, and endothermic. Finally, future research was suggested to focus on optimization to enhance the performance of the MCC-based adsorbents, carrying out the adsorption on real wastewater instead of synthetic ones as well as expanding the range of adsorbates to include other contaminants such as chlorophenols, herbicides, pesticides and others in addition to dyes and heavy metals.

Greener production of microcrystalline cellulose (MCC) from Saccharum spontaneum (Kans grass): Statistical optimization

In this study, microcrystalline cellulose (MCC) was isolated from Saccharum spontaneum by integrating alkaline delignification, chlorine-free bleaching, and acid hydrolysis treatments, through an environment friendly and sustainable method. To minimize acid concentrations, the acid hydrolysis conditions were optimized using Taguchi orthogonal L₉ design that evaluated the influences of reaction time, temperature, acid concentration and solution to pulp ratio on the physical and chemical characteristics of MCC. The cellulose source at its different stages of processing was submitted to various analytical techniques for morphological and physiochemical investigations. The highest MCC yield optimized was 83%. This process is favorable due to the use of very low (5% H₂SO₄) acid concentration, low corrosivity, effluent reduction, and cost-effectiveness. Detailed analyses showed that the isolated MCC has good crystallinity and thermal stability and hence expected as a high-value precursor for the production of polymer biocomposites for diverse applications.

Extraction and characterization of microcrystalline cellulose from waste cotton fabrics via hydrothermal method

A large amount of accumulated waste cotton fabrics (WCFs) have caused environmental problem and depletion of resources. The extraction of microcrystalline cellulose as value-added products is one of the effective ways to the recycling of WCFs. This study aimed to extract microcrystalline cellulose from WCFs by the hydrothermal method and compare the extracted microcrystalline cellulose (EMC) with Avicel PH101 microcrystalline cellulose (MCC). The EMC was extracted under hydrothermal conditions (solid-liquid ratio 1:30, HCl concentration 0.6 mol/L, 150 °C, 100 min), with a yield and the degree of polymerization of 85.54% and 228, respectively. The samples were characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, nuclear magnetic resonance, thermogravimetric analysis and contact angle testing. The detailed analyses showed that the properties of EMC prepared from WCFs are similar to those of commercial MCC. The results indicated that WCFs is a critical and potential low-cost raw material to prepare MCC.

Preparation of Maleic Anhydride Grafted Polybutene and Its Application in Isotactic Polybutene-1/Microcrystalline Cellulose Composites

Microcrystalline cellulose (MCC) offers great potential to improve the mechanical and crystallization properties of isotactic polybutene-1 (iPB) because of its low cost, biodegradability, renewability and excellent mechanical properties. However, the compatibility of polar MCC and non-polar iPB is poor. In this study, maleic anhydride grafted polybutene (MAPB) was prepared by the solution method and was used as a compatibilizer in the fabrication of iPB/MCC composites by using a twin screw extruder. The ultimate tensile strength, tensile modulus, flexural strength, flexural modulus of the iPB/MCC composites increased by 3.1%, 16.5%, 10.7%, 6.5%, respectively, compared with that of pure iPB. With MAPB addition, these values increased by 17.2%, 31%, 17.5% and 10%, respectively, compared with that of pure iPB. The heat-distortion temperature and thermal-decomposition temperature of all composites increased with an increased MCC content. The non-isothermal crystallization of the iPB/MCC composites shows that MCC addition can promote iPB crystallization, because the non-isothermal crystallization curve of the composites moves toward a higher temperature, especially after MAPB addition. Scanning electron micrographs indicate that the compatibility of the iPB/MCC has been enhanced significantly.