Chitosan Membranes Research Articles

Enhancing antibacterial activity and air filtration performance in electrospun hybrid air filters of chitosan (CS)/AgNPs/PVA/cellulose acetate: Effect of CS/AgNPs ratio

The increase in particulate matter (PM), especially PM2.5, has become a global threat to human health. To get rid of this severe pollutant, air filtration is forecasted as a promising, cost-effective, and effective method. This study utilized dual-spinneret electrospinning to fabricate the electrospun hybrid nanofibrous membranes (EHMs) of chitosan (CS)/silver nanoparticles (AgNPs)/polyvinyl alcohol (PVA)/cellulose acetate (CA). The effect of CS/AgNPs ratios was also investigated to obtain high-efficient air filtration membranes with outstanding antibacterial activity. Results disclosed that EHMs containing high AgNPs content improved the filtration performance and antibacterial properties while decreasing the wettability and tensile strength of EHM membranes. In addition, the EHM1 was found to be the most effective air filter membrane due to its high filtration efficiency of 99.78 % (PM2.5), low-pressure drop of 61.15 Pa, high-quality factor of 0.09 Pa−1, and enhanced inhibition zone of 100–141 %. Thus, this study suggests that the EHMs of CS/AgNPs/PVA/CA with a high AgNPs/CS ratio fabricated via a dual-electrospinning technique are expected to be a promising material choice for an air filter with efficient filtration performance and excellent antibacterial activity, resulting in a more sustainable and healthier future.

Fabrication and properties evaluation of chitosan/BaTiO3 composite membranes for the periodontitis treatment

Periodontitis gradually damages the hard and soft tissues surrounding the tooth, leading to tooth loss. In recent years, the use of biomaterials in periodontitis treatment has expanded, including gels, nanoparticles, microparticles, fibers, and membranes. Among these, membranes have more clinical applications. Due to the ability of the piezoelectric material to regenerate damaged tissues, the aim of this study was to create piezoelectric composite membranes. To achieve this, Barium titanate powder (BaTiO3 powder)—a piezoelectric substance—was synthesized using the hydrothermal method and analyzed with X-ray diffraction (XRD) and Field emission scanning electron microscopy (FESEM). Four types of membranes were fabricated using solvent casting method: three composite membranes with chitosan matrix and BaTiO3 fillers (at 3%, 6%, and 9% weight), and one chitosan membrane without BaTiO3. The microstructure of the membrane surfaces, agglomeration of BaTiO3 in membranes, and hydrophilicity, antibacterial, and electrical properties of the membrane were also investigated. The results indicated that membranes containing 3 and 6% BaTiO3 had suitable surface structure for the periodontitis treatment. Agglomeration of BaTiO3 particles was higher in the membrane containing 9% BaTiO3. The large amount of BaTiO3 improved the antibacterial properties of the membranes. Additionally, the membranes containing BaTiO3 had high electrical properties, especially those with 3% and 6% BaTiO3. Therefore, composite membranes containing BaTiO3, especially membranes containing 6% BaTiO3, are more favorable options than those without BaTiO3 for periodontitis treatment.

Effect of glycerol on properties of chitosan/chlorhexidine membranes and antibacterial activity against Streptococcus mutans.

Chitosan membranes with glycerol can function as an effective dispersing agent for different antibiotics or active ingredients that can be used in the treatment of diseases present in the oral cavity. The effects of the addition of glycerol on the mechanical, water absorption, swelling, pH, thickness, disintegration, rugosity, and antibacterial properties of chitosan-chlorhexidine- glycerol membranes were investigated in this study. Mechanical results indicated that chitosan membranes' rugosity, strength, flexion, and thickness differed at loading 1, 3, 5, 10, 15, and 20% of glycerol (p < 0.05). The chitosan membranes' rugosity, dissolution, strength, and pH results were significantly enhanced by the presence of glycerol at 3, 5, and 10% concentrations. In this investigation, the antimicrobial activity model used was the inhibition of Streptococcus mutans CDBB-B-1455 by chitosan-chlorhexidine membranes. It was observed that there was no change in inhibition with different concentrations of glycerol. The results suggest that chitosan-glycerol-chlorhexidine membranes may be a potential candidate for topical antiseptic application in buccal-dental disorders caused by S. mutans, such as caries, periodontal diseases, and oral squamous cell carcinoma, helping to prevent the development of serious conditions that can compromise human health.

Functional and antibacterial characterization of electrospun nanofiber membranes made of chitosan and polyvinyl alcohol

The development of nanomaterials with improved functional characteristics is a priority because of their applicability in medicine. Therefore, in this study, chitosan nanofiber membranes were electrospun with polyvinyl alcohol supplemented with carboxymethyl cellulose and pectin. The membrane characterization included identifying the functional groups of each polymer, the surface appearance, and the absorption capacity of aqueous media, simulating the exudates of skin diseases. Membrane weight loss was close to 50 % during the first day, and they preserved their integrity throughout the study. The mechanical characteristics demonstrated that the membranes with adjuvants are flexible and tough. The rigidity of the membranes was between 10.49 MPa and 22.65 MPa, and this rigidity decreased with the addition of chitosan and pectin. With chitosan, the elongation at break (8.25 %) was higher but the elastic modulus (450.78 MPa) was lower than those recorded with the other polymers. The effect against Staphylococcus aureus occurs due to chitosan and only by contact. In particular, an inhibition zone increased with the addition of chitosan (178.21 mm2). However, carboxymethyl cellulose showed the least shrinkage (4.4 %). Therefore, it is possible to produce nanofibers to make chitosan and polyvinyl alcohol membranes with improved functional characteristics by the addition of adjuvant agents as an alternative to other skin healing materials.

Analysis of Platinum (Pt) Ion Biosorption Performance Using Chitosan

Platinum Group Metal has a continuous increase in demand. The demand for platinum is divided into four segments: automotive, jewelry, industry, and investment. However, the availability of PGM is limited, resulting in the potential scarcity of the metal and the necessity for developing more effective and environmentally friendly methods. Biosorption serves as an alternative method for capturing metal ions using biological materials. Biosorption is chosen due to its low operational costs, environmentally friendly, and utilization of abundant natural biomaterials. This study aims to analyze the influence of chitosan concentration and adsorbent surface area on the biosorption process of Pt metal from H2PtCl6 solution. The biosorption method utilizes chitosan membranes produced by mixing chitosan with PVA and using glutaraldehyde as a crosslinker to stabilize chitosan in solution. The research involves testing using UV-VIS, SEM-EDX, and FTIR techniques to analyze the concentration of adsorbed Pt metal, morphology, and functional groups on the membrane. The results indicate that chitosan is an effective adsorbent for absorbing Pt metal ions, particularly in the CS/PVA adsorbent with a surface area of 352 mm2 and a chitosan concentration ratio of 2 gram, resulting in percentage adsorption of 47.948%.

Investigation of spectroscopic, water barrier and thermal characteristics of ameliorated chitosan membrane

Investigation of spectroscopic, water barrier and thermal characteristics of ameliorated chitosan membrane

Evaluation of the Efficiency of a Chitosan Membrane in Removing Gallic Acid from Wastewater Using Adsorption in Batch Mode and Separation by Dead-End Filtration

Abstract: This study assesses the efficacy of adsorption and separation techniques for removing gallic acid (GA) from wastewater using a chitosan membrane (Chi-1.5%). The effect of GA concentration, mass of adsorbent, contact time and pH were investigated. GA adsorption was best fitted by the Freundlich and Langmuir isotherm models, with a correlation coefficient of 0.9972 and 0.9929, respectively. The maximum adsorption capacity of GA (301.70 mg/g) was calculated at pH 8.4 and 303 K. Gibbs free energy was also calculated. The negative value showed that the GA adsorption is spontaneous. On the other hand, the value of activation energy of adsorption (&lt; 7 kJ/mol) indicates that the adsorption is physical in nature. The adsorption kinetics was best fitted by the pseudo-second-order model, and the effect of pH (8.4 and 7.1) on the adsorption is explained by theoretical calculation of the fraction of ions present in solution and their affinity for the membrane. The maximum percentage of GA removal based on a dead-end filtration system was 18.58% at a GA concentration of 300 ppm, pH 8.4 and a pressure of 1 bar. Volume exclusion was found to have a very slight effect on removing GA from the aqueous phase, while adsorption played the main role in removing GA.

Exploring the Impact of Nanoparticle Stealth Coatings in Cancer Models: From PEGylation to Cell Membrane-Coating Nanotechnology.

Nanotechnological platforms offer advantages over conventional therapeutic and diagnostic modalities. However, the efficient biointerfacing of nanomaterials for biomedical applications remains challenging. In recent years, nanoparticles (NPs) with different coatings have been developed to reduce nonspecific interactions, prolong circulation time, and improve therapeutic outcomes. This study aims to compare various NP coatings to enhance surface engineering for more effective nanomedicines. We prepared and characterized polystyrene NPs with different coatings of poly(ethylene glycol), bovine serum albumin, chitosan, and cell membranes from a human breast cancer cell line. The coating was found to affect the colloidal stability, adhesion, and elastic modulus of NPs. Protein corona formation and cellular uptake of NPs were also investigated, and a 3D tumor model was employed to provide a more realistic representation of the tumor microenvironment. The prepared NPs were found to reduce protein adsorption, and cell-membrane-coated NPs showed significantly higher cellular uptake. The secretion of proinflammatory cytokines in human monocytes after incubation with the prepared NPs was evaluated. Overall, the study demonstrates the importance of coatings in affecting the behavior and interaction of nanosystems with biological entities. The findings provide insight into bionano interactions and are important for the effective implementation of stealth surface engineering designs.

Surface-engineered TiO2 nanoparticles incorporated Chitosan polymer membrane for seawater desalination: Fabrication, characterization, and performance evaluation

The effect of surface coating over titanium dioxide nanoparticles (TiO2-NPs) incorporated with chitosan (TiO2-NPs/chitosan) was evaluated as a reverse osmosis membrane (RO) for enhanced performance on seawater desalination. The impact of surface coating on the chitosan membrane performance in seawater reverse osmosis (SWRO) was investigated by altering the mass of TiO2-NPs (0.25 g and 0.5 g) used for the surface coating RO membrane. TiO2-NPs were applied to the membranes using a surface coating technique and dried to create a sturdy polymer structure. The characteristic of fabricated membranes shows the function group reflects on organic compounds from /chitosan membranes polymer (–OH, -CH, C=O, C-O-C, -CH3, C-O, and NH2). In addition, TiO2-NPs are expressed in the wavenumber range of 850-500 cm-1, which characterizes the presence of Ti-O-Ti bonds. Morphological and crystal analyses of TiO2-NPs incorporated in chitosan membrane show significantly smaller pores formed because TiO2-NPs are essential in the high permeability performance under the amorphous phase structure. Also, the high performance of fabricated membranes was evaluated against water flux and salt. Adding TiO2-NPs can decrease the water flux value by 23 L m-2 h-1 and increase salt rejection by 52.94%. In optimized pH, the seawater desalination had efficient recovery.

Tailoring polyethylene oxide-modified cross-linked chitosan/PVA nanofibrous membranes: Burn dressing scaffold developed for mupirocin release

In emergency treatment research, the focus on chitosan-based products for wound healing has been consistent. This study specifically explores a dressing made by mixing chitosan (CS) and poly (vinyl alcohol) PVA. Using electrospinning technology, nanofiber membranes of CS and PVA are created with the assistance of non-toxic and hydrophilic polyethylene oxide (PEO). The outcome is a new nanofibrous membrane loaded with mupirocin, designed for healing burn wounds.The study delves into the influence of PVA, CS, and PEO concentrations on the structural and chemical characteristics of the mats. This comprehensive exploration involves techniques such as Scanning Electron Microscope (SEM), Atomic Force Microscopy (AFM) imaging, Fourier Transform Infrared Spectrometry (FTIR analysis), and Contact angle measurements. Additionally, the research evaluates the antibacterial performance and biomedical behavior of the developed scaffolds.PEO proves beneficial in the electrospinning process, contributing to smoother fibers. Meanwhile, the addition of CS and mupirocin leads to formation of the thinner nanofibers (251 ± 5 μm and 263 ± 4 μm, respectively) and scaffolds with higher swelling (up to ∼3.5 times at 90 min). Notably, the (MTT) assay confirms the non-cytotoxicity of the fabricated nanofibers, with proliferations exceeding ∼85% for all samples.The crosslinked samples released the drug more slowly than the non-crosslinked dressings, with 80% of the scaffolds releasing the drug within 24 h. The in-vivo investigations suggested that the drug-containing scaffolds performed reliably and showed promise as a medical dressing for treating burn wounds.

Fabrication and Characterization of Chitosan-Polyvinyl Pyrolidone K-30 for Creatinine Transport Membranes

The investigation of membrane-based hemodialysis is an interesting study due to its efficacy in eliminating metabolic waste compounds, such as creatinine, from the body. However, not all membrane types exhibit optimal transport capabilities, necessitating modifications. In this study, we conducted modifications on chitosan (CS) membranes by incorporating polyvinyl pyrrolidone K-30 (PVP K-30) and assessing their physicochemical characteristics. The modified membrane underwent characterization and subsequent evaluation of its transport capabilities. The primary objective of this research is to design a membrane composed of chitosan and PVP K-30 with enhanced creatinine transport capabilities. The study commenced with the fabrication of CS membranes combined with CS-PVP, involving six variations of CS and PVP K-30 with volume ratios of 5:0, 4:1, 3:2, 1:1, 2:3, and 4:1. The resulting solution was then printed into a flat sheet membrane. All completed membranes underwent comprehensive characterization, including tests for functional groups using Fourier Transform Infrared (FTIR), membrane weight and thickness, porosity, water absorption, swelling, hydrophilicity, pH resistance, and biodegradation. In the final phase, the membrane was utilized in the creatinine transport process. FTIR analysis of the CS-PVP K-30 membrane revealed O-H and N-H group spectra at wave numbers 3363.06 cm-1 and 1587.17 cm-1, indicating hydrogen bonding between the two polymers. Characterization tests demonstrated that the CS-PVP membrane exhibited increased porosity, water absorption, swelling, and hydrophilicity. In the creatinine transport test, the CS-PVP membrane demonstrated enhanced creatinine transport ability compared to the CS membrane. The highest clearance value for creatinine was observed in the CS-PVP5 membrane, with an increase in the amount of PVP K-30 correlating with an elevated creatinine clearance value. The creatinine clearance values for the CS membrane, CS-PVP1, CS-PVP2, CS-PVP3, CS-PVP4, and CS-PVP5 were 0.30, 0.36, 0.37, 0.39, 0.42, and 0.46 mg/dL, respectively.

An optical fiber chlorogenic acid sensor using a Chitosan membrane coated bent optical fiber probe

Hydrogel polymers have hydrophilic function groups bonded on the polymer's backbone network. Water molecules and compounds soluble in aqueous solution can permeate into hydrogel's network. This property was employed in this work in developing an optical fiber chemical sensor for detecting chlorogenic acid (CGA). A Chitosan membrane was coated on a bent optical fiber probe (BOFP) by simply dipping the BOFP into a Chitosan solution, which was made by dissolving solid Chitosan in a 2 % acetic acid solution, and pulling out. When such a Chitosan-coated BOFP was exposed to CGA in an aqueous sample solution, CGA molecules permeate into the Chitosan membrane, and were detected through monitoring the compound's intrinsic optical absorption signal at 400 nm. Chitosan has one amine group on each of its glucose rings, which helps the membrane concentrating CGA (a weak acid) from aqueous sample solution. Therefore, the sensor shows high sensitivity in detecting CGA with a detection limit of 0.018 μg/mL. The sensor's response to CGA is reversible, because CGA permeation into/out of the polymer network is a reversible process. The effectiveness of the developed sensor for detecting CGA was verified though analyzing CGA in green coffee extract products. The analytical results obtained with the developed sensor agree well with results obtained with a traditional UV/Vis optical absorption spectrometric method. The effectiveness of the sensor for analyzing CGA in green coffee extract samples was also verified through standard addition and recovery experiment with obtained recovery rate ranging from 97 % to 100 %.

Novel chitosan-ionic liquid immobilized membranes for PEM fuel cells operating above the boiling point of water

Novel chitosan (CS) composite membranes modified with ionic liquids (ILs), namely, 1-Hexyl-3- methylimidazolium tricyanomethanide ([HMIM][TCM]), Diethylmethylammonium methanesulfonate ([DEMA][OMs]), were synthesized to be used as a polymer electrolyte membrane (PEM) in for PEM fuel cells. The ionic conductivities of the prepared membrane samples were evaluated using electrochemical impedance spectroscopy (EIS). The CS is one of the attractive choices of green and sustainable membrane materials in PEMs because of its chemical tunability and cost-effectiveness. The membranes were prepared by solution casting followed by a solvent evaporating procedure. The low proton conductivity of pristine CS biopolymer was enhanced by the incorporation of ILs in the membrane framework. Tensile testing confirmed the excellent membrane mechanical integrity. A significant enhancement in the membranes’ characteristics was observed upon the introduction of [DEMA][OMs] into its matrix. The experimental results showed enhanced proton conductivities of the prepared membranes along with enhanced flexibility. The proton conductivity of pristine CS membrane was increased from 8.4 × 10−4 to 1.25 × 10−2 S/cm and 1.1 × 10−2 S/cm when a 30 wt% [HMIM][TCM] and 100 wt% [DEMA][OMs] were added, respectively. Synergistic effects of amine and imidazolium-based ILs on the electrical, structural, water uptake, and thermal properties of CS-based biopolymer solid electrolyte membranes are reported for the first time in this work. The aforementioned characterization results demonstrate the potential of using these membranes in PEM fuel cells operating above the boiling point of water and at a lower cost. This work showed that there should be an optimization amount of the ILs content in the membrane to maintain its mechanical integrity.

A novel chitosan-glutamic acid membrane for multi-pollutant amputation: Investigational and RSM optimizations

The novel glutamic acid crosslinked chitosan membrane (CsG) was fabricated and tested for its adsorption capabilities for the removal of multiple pollutants like Cr (VI), cyanide, fluoride and diclofenac sodium from wastewater. This fabricated CsG membrane was characterized by various techniques like FT-IR, SEM, EDX and XRD, BET to assess its structural, compositional and morphological properties. The working parameters studied by batch experiments were solution pH, CsG dose, contact time, pollutant concentration and solution temperature. The CsG membrane exhibited maximum adsorption capacity of 410.7 mg/g, 310.2 mg/g, 14.3 mg/g, 132.7 mg/g for Cr (VI), cyanide, fluoride and diclofenac respectively. The validation of the operational parameters was performed by Response Surface Methodology (RSM). The experimental data fitted well with Langmuir isotherm model and followed pseudo second order kinetics for all the four targeted contaminants. The spontaneity of the process was checked by thermodynamics studies. The high partition coefficients of 7669 L/kg Cr(VI), 23,309 L/kg (CN−), 649 L/kg (F−) and 2613 L/kg (DFC) are the indicators of excellent attractive interaction between CsG membrane and target toxicants. The CsG membrane showed efficient regenerative adsorption properties up to 5 adsorption-desorption cycles. Overall, the developed novel CsG membrane promised as an effective material for the removal of multiple number of pollutants from water.

Chitosan-based adsorptive membrane modified by carboxymethyl cellulose for heavy metal ion adsorption: Experimental and density functional theory investigations

Low adsorption capacity and weak mechanical stability are the main drawbacks of chitosan (CS)-based adsorptive membranes for heavy metal ion removal. Polyvinyl alcohol (PVA) has been used to improve the mechanical stability of CS membranes, but adsorption capacity is disregarded. In the current study, the surface of the chitosan/polyvinyl alcohol (CP) membrane was modified using carboxymethyl cellulose (CMC) to increase its heavy metal ion adsorption capacity. Experimental and density functional theory (DFT) calculations were used to evaluate the heavy metal ion (As3+ and Cr3+) adsorption capabilities of CP and carboxymethyl cellulose-functionalized CP (CMC-CP) membranes. The batch adsorption process presented a higher heavy metal adsorption capacity of the CMC-CP membrane (As3+/CMC-CP = 234.78 mg/g and Cr3+/CMC-CP = 230.12 mg/g) compared to the CP membrane (As3+/CP = 89.02 mg/g and Cr3+/CP = 75.61 mg/g). The heavy metal/CMC-CP complexes confirmed higher adsorption energies (As3+/CMC-CP = −23.62 kcal/mol and Cr3+/CMC-CP = −23.21 kcal/mol) than the heavy metal/CP complexes (As3+/CP = −3.47 kcal/mol and Cr3+/CP = −2.92 kcal/mol). The electronic band structure was higher for CMC-CP (5.42 eV) compared to CP (4.43 eV). Experimental and theoretical findings were close, implying that the CMC-CP membrane has superior heavy metal adsorption capability than the CP membrane.

Construction of robust DA@CNTs/CS hydrogel coatings on hydrophobic PVDF membrane by deposition of self-assembly for efficient separation of oil-water emulsion and dye wastewater

With the rapid development of industry, the problem of water pollution has become increasingly serious. Though there are many separation materials available to solve this problem, how to separate multiple wastewater at the same time remains a challenge. Hydrogel coating is suitable for use in the field of oil–water separation, and chitosan (CS) is effective in removing anionic dyes. Therefore, the preparation of separation membranes with hydrogel coating containing CS and dopamine (DA) can effectively separate oil–water emulsion and anionic dye wastewater. In this paper, DA@CNTs/CS hydrogel coating was prepared by sequentially coating Cu2+, DA@CNTs, Cu2+ and CS on the surface of polyvinylidene fluoride (PVDF) membrane by deposition of self-assembly, which enhanced the hydrophilicity of the membrane and made it highly underwater oleophobic and antifouling. The alkali treated PVDF membrane contained a large amount of –OH, Cu2+, which formed coordination bonds with –OH, CS, and DA and the hydrogel coating could be stably loaded on the membrane. In addition, the introduction of rigid CNTs effectively improved the performance of the modified membrane under extreme conditions such as high pH and high salt concentration. PVDF-DA@CNTs/CS membrane had an ideal pure water flux (PWF) of 1470 (L·m−2·h−1) and the separation efficiency of 99.7 % for anionic dye and 99.4 % for oil–water emulsion. The contaminant on the membrane surface can be quickly removed by washing with DI water. The overall performance of the membrane is also maintained at a very high level of long-term filtration of wastewater. In summary, this study provides a new approach to complex wastewater treatment technology.

Synthesis of aminolyzed gelatin-mediated chitosan as pH-responsive drug-carrying porous scaffolds

Bio-based drug delivery devices have gained enormous interest in the biomedical field due to their biocompatible attributes. Extensive research is being conducted on chitosan-based devices for drug delivery applications. Chitosan being hydrophobic under neutral conditions makes it difficult to interact with a polar drug of curcumin. We tended to make it polar through sol-gel synthesis and modification via PEGylation, alkaline hydrolysis, and aminolysis. Such alterations could make the chitosan-based scaffolds porous, hydrophilic, amino-functionalized, and pH-responsive. The ninhydrin assay confirmed that a successful aminolysis occurred, and the chemical interaction among the precursors was explained under infrared spectroscopy. The scanning morphology of the optimum aminolyzed membrane appeared to be porous with an average pore size of 320 ± 20 nm. The aminolyzed chitosan membrane was found thermally stable up to 310 °C, hydrophilic with a water contact angle of 23.4°, moderate flowablity, and porous (97 ± 5 %, w/w) against ethanol. The curcumin-loaded chitosan membrane expressed the UV-protection behavior of 99 %. The curcumin-loading and release phenomena were found pH-responsive. The curcumin release results were evaluated through specific kinetic models. This study could be the first report on the amphiphilic, porous, and swellable drug-loaded gelatin/chitosan membrane with pH-responsive loading and release of curcumin for potential drug delivery applications.

Immobilization of Papain in Chitosan Membranes as a Potential Alternative for Skin Wounds.

Papain (an enzyme from the latex of Carica papaya) is an interesting natural bioactive macromolecule used as therapeutic alternative for wound healing due to debridement action in devitalized or necrotic tissues. However, its use in high doses can induce potential skin irritation and side effects. In this study, experiments explored the ability of chitosan membrane to immobilize papain, consequently improving enzymatic activity and controlling enzyme release. Papain-loading capacity was tested via experiments of force microscopy (AFM), scanning electron microscopy (SEM-FEG), and X-ray diffraction analyses. Fourier transform infrared spectroscopy and thermal analyses assessed the enzyme interactions with the copolymer. The investigation of the feasibility of membranes included pH on the surface, elasticity, and breaking strength measurements. The surface wettability and swelling capacity of different formulations revealed the best formulation for in vitro papain release experiments. The membranes had a transparent, rough, crystalline characteristic, which was homogeneous with the membrane within the neutrality. The immobilization of papain in the chitosan membrane resulted in a decrease in the vibration band characteristic of pure papain, suggesting a displacement in the vibration bands in the FTIR spectrum. The presence of papain decreased hydrophobicity on the surface of the membrane and disturbed the membrane's ability to swell. Chitosan membranes containing papain 2.5% (0.04 g) and 5.0% (0.08 g) preserved feasible properties and improved the enzymatic activity compared (0.87 ± 0.12 AU/mg and 1.59 ± 0.10 AU/mg) with a free papain sample (0.0042 ± 0.001 AU/mg). Concentrations of over 10% (0.16 g) led to phase separation into membranes. Chitosan membranes exhibited a slow papain release behavior adjusted via the Higushi model. The experimental achievements suggest a novel and promising method for the enhancement of papain. The results indicate the potential for prolonged bioactivity for use on wounds.

A Novel Candidate for Guided Tissue Regeneration: Chitosan and Eggshell Membrane.

Background The primary cause of adult tooth loss is commonly attributed to periodontal disease, a condition that weakens the supportive structures around the teeth. In addressing periodontal diseases, surgeons often employ the guided tissue regeneration (GTR) technique, which involves the use of a barrier membrane. Aim The aim of the present study is to assess the composition and mechanical strengthofchitosan and eggshell membrane. This research was conducted to provide insights into their potential application in facilitating tissue regeneration. Materials and procedures Chitosan and eggshell membrane were combined to create the membrane. Scanning electron microscopy (SEM) using FEI Quanta FEG 650 SEM (JSM IT-800, JEOL Ltd., Akishima, Tokyo, Japan) was carried out, and mechanical properties wereused to measure the parameters of membrane characterization. Results In the dry condition, the membrane's tensile strength was 0.30 MPa and its elongation at break was 8.2%. In the wet condition, the membrane's tensile strength was 0.13 MPa and its elongation at break was 22.6%. The SEM results depictedmembrane surface with pore sizes ranging from 16 to 100 meters, and the result obtained from membrane porosity test was 31.2%. Conclusion The chitosan-eggshell membrane exhibited a fibrous surface with a desirable pore size for use as a GTR membrane, but it has low mechanical strength.

Parameters affecting synthesis of sulfonated chitosan membrane for poly electrolyte membrane in fuel cells

Parameters affecting synthesis of sulfonated chitosan membrane for poly electrolyte membrane in fuel cells