Molecular Weight Chitosan Research Articles

Eco-friendly enhanced microwave synthesis of polyaniline/chitosan-AgNP composites, their physical characterisation and antibacterial properties

An eco-friendly enhanced microwave (MW) method was used to prepare antibacterial polyaniline/chitosan-silver nanoparticle (PANI/Ch-AgNP) composites at room temperature through the chemical in situ polymerisation of aniline using potassium iodate (KIO3) as oxidising agent and different molecular weight chitosans (Chs) in the presence of 10 wt% of AgNP in the starting reaction mixture for the period of 10 min. The comparable analysis of physical, morphological and antibacterial properties PANI/Ch-AgNP samples synthesised by a classical chemical synthesis (CS) and enhanced MW method showed that AgNP influenced the aniline polymerisation in the presence of Ch biopolymer in the PANI-based composite. Enhanced crosslinking of Ch with PANI with some porous nanostructures was observed in MW PANI/Ch-AgNP 1:1 composites. Furthermore, a predominant Ch morphology was noticed in all CS PANI/Ch-AgNP 1:1 samples which indicates that in classical synthesis method the presence of AgNP constraints PANI fibre formation and reduces electrical conductivity in these composites in comparison with the ones prepared by MW method. All PANI/Ch-AgNP 1:1 composites exhibited better bactericidal (bacterial killing) efficacy against both types of bacteria than any of the Chs or PANI control samples. These results suggested that facile, scalable, and low-cost enhanced MW method can be used for tuning PANI formation conditions favouring the particular physical properties of PANI/Ch-AgNP composites.

Polyethylenimine linked with chitosan improves astaxanthin production in Haematococcus pluvialis

Astaxanthin is receiving increasing interest as an antioxidant and high value-added secondary metabolite. Haematococcus pluvialis is the main source for astaxanthin production, and many studies are being conducted to increase the production of astaxanthin. In this study, we linked polyethylenimine (PEI) with chitosan to maintain astaxanthin-inducing ability while securing the recyclability of the inducer. Astaxanthin accumulation in H. pluvialis was induced to 86.4pg cell-1 with the PEI-chitosan fiber (PCF) treatment prepared by cross-linking of 10μM PEI and low molecular weight (MW) chitosan via epichlorohydrin. PEI concentration affected the astaxanthin accumulation, whereas the MW of chitosan did not. In addition, the PCF treatment in H. pluvialis increased the reactive oxygen species (ROS) content in cells, thereby upregulating the transcription of enzymes involved in astaxanthin biosynthesis. PCF can be reused multiple times with the maintenance of over 90% of the astaxanthin production efficiency. This study offers a reusable PCF stimulation strategy for enhancing natural astaxanthin content, and PCF treatment will easily increase the production scale or reduce production costs by using recyclability that is not available in current methods. KEY POINTS: • Polyethylenimine-chitosan fiber (PCF) was applied to Haematococcus pluvialis • PCF promotes astaxanthin accumulation by enhancing oxidative stress in H. pluvialis • PCF can be reused multiple times with maintaining over 90% production efficiency.

Smart redox-sensitive micelles based on chitosan for dasatinib delivery in suppressing inflammatory diseases

Dasatinib (DAS) exhibits anti-inflammatory effects by retrieving the balance between inflammatory and anti-inflammatory cytokines secreted by macrophages. The aim of this study was the development of redox-responsive micelles with the potential of passive targeting and on-demand drug release for DAS delivery to macrophages. For this purpose, two molecular weights of chitosan (CHIT) were conjugated to DAS at different molar ratios using 3,3′-dithiodipropionic anhydride (DTDPA) as disulfide bond containing linker to synthesize a series of CHIT-S-S-DAS amphiphilic conjugates. Micelles obtained by the sonication method had particle sizes of 129.3–172.2 nm, zeta potentials of +17.5 to +20.9 mV, drug contents of 0.90–7.20 %, CMC values of 35.3–96.6 μg/ml, and exhibited redox-responsive in vitro drug release. Optimized micelles were non-toxic and dramatically more efficient than non-redox responsive micelles in reducing TNF-α and IL-6 and increasing IL-10 secretion from LPS-stimulated RAW264.7 cells. Furthermore, the redox-responsive micelles were able to reduce the mice paw edema, reduce the plasma levels of pro-inflammatory cytokines and increase plasma level of IL-10, considerably more than free DAS and non-redox responsive micelles in carrageenan-induced mice paw edema model of inflammation.

The Immobilization of Laccase on Mixed Polymeric Microspheres for Methyl Red Decomposition

Means of eliminating water pollutants or transforming them into less hazardous compounds by green catalysis are desired. The current work was developed with the goal of discovering supports suited for laccase (Lc) immobilization. The effect of the chitosan (CS) molecular weight (Mw) or the polyacrylic acid (PAA) addition was evaluated in microsphere formulation and enzyme immobilization by ESEM, rheology, operational stability, and kinetics. As a practical application, the synthesized products were tested in the methyl red (MR) decomposition and the product identification was performed by high-resolution mass spectrometry. Depending on the required properties, the laccase activity profile (pH, temperature, storage, and Michaelis–Menten parameters) and rheological strength can be modulated by varying the molecular mass of CS or by adding PAA in the support formulation. The immobilized products having the best features regarding MR degradation and recycling abilities were the medium Mw CS microspheres and the system with low Mw CS complexed by PAA, respectively. The degradation mechanism of the dye was proposed accordingly with the identified products by mass spectroscopy. The findings emphasize the potential of the proposed immobilization products to be exploited as viable biocatalysts for dye-contaminated water.

Analysis of the interaction between chitosan with different molecular weights and casein based on optical interferometry

Chitosan can be used as a stabilizer in dairy products to help suspend and stabilize casein micelles, but the molecular weight (MW) effect of chitosan has not been much explored. This work aimed to construct interaction models with casein using chitosan with MW of 30 kDa, 150 kDa, 250 kDa and 300 kDa to reveal the effect of MW on the structure and stability of chitosan-casein complexes. These models were based on the ordered porous layer interferometry (OPLI) system that can generate time-resolved signals to monitor the chitosan-casein interaction process dynamically in real time. The zeta potential, size distribution, binding mechanism and binding constants of chitosan-casein complexes with different MW were also analyzed. It was found that the chitosan and casein at pH 5.5 with the strongest interaction. The zeta potential and size analysis of chitosan-casein complexes showed opposite trends with MW before and after the saturation concentration, and MW(150 kDa) chitosan produced the largest size change in the bridging flocculation stage. The order of binding constants for chitosan-casein interactions is MW(300 kDa) < MW(250 kDa) < MW(30 kDa) < MW(150 kDa). In addition to the attraction between chitosan and casein by electrostatic driving forces, the dependence of the hydrophobic interaction between chitosan molecules on MW all influenced the interaction with casein. The dynamic monitoring and accuracy of the OPLI technique open up more possibilities to obtain the interactions of chitosan/casein and other biopolymers in different condition variables.

Assessment of the Antibiofilm Performance of Chitosan-Based Surfaces in Marine Environments

Marine biofouling is a natural process often associated with biofilm formation on submerged surfaces, creating a massive economic and ecological burden. Although several antifouling paints have been used to prevent biofouling, growing ecological concerns emphasize the need to develop new and environmentally friendly antifouling approaches such as bio-based coatings. Chitosan (CS) is a natural polymer that has been widely used due to its outstanding biological properties, including non-toxicity and antimicrobial activity. This work aims to produce and characterize poly (lactic acid) (PLA)-CS surfaces with CS of different molecular weight (Mw) at different concentrations for application in marine paints. Loligo opalescens pens, a waste from the fishery industry, were used as a CS source. The antimicrobial activity of the CS and CS-functionalized surfaces was assessed against Cobetia marina, a model proteobacterium for marine biofouling. Results demonstrate that CS targets the bacterial cell membrane, and PLA-CS surfaces were able to reduce the number of culturable cells up to 68% compared to control, with this activity dependent on CS Mw. The antifouling performance was corroborated by Optical Coherence Tomography since PLA-CS surfaces reduced the biofilm thickness by up to 36%, as well as the percentage and size of biofilm empty spaces. Overall, CS coatings showed to be a promising approach to reducing biofouling in marine environments mimicked in this work, contributing to the valorization of fishing waste and encouraging further research on this topic.

Effect of molecular weight of chitosan on properties of chitosan-Zn nanoparticles

The chitosan-Zn nanoparticles were prepared used the TPP as ionic crosslinking agent and the properties of chitosan-Zn nanoparticles were studied. EDS and XPS results showed that when the chitosan molecular weight was 200 KDa, Zn element had a higher content in chitosan-Zn nanoparticles, which indicated the coordination reaction between Zn2+ and chitosan at –NH2 and –OH. Chitosan with larger molecular weight resulted a larger mean size and zeta potential, the mean size of chitosan-200-Zn was 865.9 nm and the system of chitosan-200-Zn tended to be a stable system with zeta potential of 29.3 mV. The molecular weight of chitosan affected the wettability of chitosan-Zn nanoparticles. While the molecular weight of chitosan had no effect on the crystalline structure of chitosan-Zn nanoparticles. The findings of this study had illustrated the effect of chitosan molecular weight on the properties of chitosan-Zn nanoparticles.

The Application of Chitosan for Protection of Cultural Heritage Objects of the 15-16th Centuries in the State Tretyakov Gallery.

Microorganisms are one of the main factors in the deterioration of cultural heritage, in particular art paintings. The antiseptics currently used in painting have significant limitations due to insufficient effectiveness or increased toxicity and interaction with art materials. In this regard, the actual challenge is the search for novel materials that effectively work against microorganisms in the composition with painting materials and do not change their properties. Chitosan has pronounced antimicrobial properties but was not used previously as an antiseptic for paintings. In our study we developed a number of mock layers based on sturgeon glue, supplemented which chitosan (molecular weight 25 kDa or 45 kDa), standard antiseptics for paintings (positive controls) or without additives (negative control). According to Fourier transform infrared spectroscopy and atomic force microscopy, the addition of chitosan did not significantly affect the optical and surface properties of this material. The ability of chitosan to effectively protect paintings was shown after inoculation on the created mock-up layers of 10 fungi-destructors of tempera painting, previously isolated from cultural heritage of the of the 15-16th centuries in the State Tretyakov Gallery, on the created mock layers. Our study demonstrated the principled opportunity of using chitosan in the composition of painting materials to prevent biodeterioration for the first time.

Ultra-low protein residue of chitosan by one step H2O2 and sodium dodecyl sulfate treatment

Residual protein in chitosan-based biomaterials may cause inflammation, allergy, and immune rejection after surgery, impeding their clinical application. Facile production of chitosan with ultra-low protein content (residual protein <0.2 %) is yet to be addressed. Herein, we proposed a one-step method for preparing chitosan with residue protein content <0.2 % by using hydrogen peroxide and sodium dodecyl sulfate, which is simple, time-saving, cost-effective, and acid/alkali-free. Notably, the molecular weight of chitosan can be reduced simultaneously. The effects of experimental parameters (i.e. hydrogen peroxide concentration (0.01 %–1 %), SDS concentration (5 %–20 %), and reaction temperature (50 °C–70 °C)) on the protein removal and molecular weight decrease were systematically analyzed by response surface methodology. The results show that temperature and H2O2 concentration are the main parameters affecting the deproteinization of chitosan. Further characterizations on the resulting ultra-low protein residue chitosan revealed unchanged chemical structure, enhanced crystallinity, and reduced thermal stability. The proposed one-step deproteination method may have great potential for industrial mass production of ultra-low protein residue chitosan.

Dyeing Recycled Cotton Fibers Using Curcuma Longa and Pterocarpus Santalinus Natural Dyes and Bio-mordant Chitosan

ABSTRACT Problems such as the depletion of natural resources and the increase in environmental pollution brought about by industrialization, the concept of recycling gained great importance. Natural dyes have gained importance again with the increase in environmental awareness. For this purpose, the dyeability of recycled cotton yarns with natural dyes was examined in order to both protect natural resources and reduce the waste water load in dyeing. The paper also discussed a comparison between different ways to mordant cotton with different molecular weight chitosan. Although it was seen by FTIR analysis that cotton fibers were dyed, the presence of chitosan could not be clearly seen. It was explained by the use of low amounts of chitosan. It was observed that the mordanting processes performed with chitosan contributed to the increase in the color strengths, and higher color depths were obtained with the increasing chitosan concentration. Simultaneous mordanting in Curcuma longa dyeing, mordanting before Sandalwood dyeing provided higher color depths than others. The washing fastness of the samples dyed with Curcuma longa revealed the necessity of fastness improvement processes. It was concluded that chitosan mordanting process was effective in terms of sustainable natural dyeing, but it was necessary to improve fastness.

EFFECT OF CHITOSAN-BASED SPRAYING ON THE QUALITY OF HIGHBUSH BLUEBERRIES (SUNRISE CULTIVAR)

The consumption of highbush blueberries has been growing rapidly in recent years due to their taste and health-promoting qualities. Various solutions have been sought to obtain the highest quality fruit after harvest. In the era of eco-friendly products, it is important that the methods used are natural and ecological. For this purpose, chitosan (CH) was sprayed five times on highbush blueberry bushes before harvesting. Different molecular weights of CH (5, 12, 21, 50, 125, and 500 kDa) were used in this study. The physical and biochemical characteristics of the fruit were investigated. The antioxidant activity, microbial contaminants, and mycotoxins in fruit were also analysed. Application of CH affected the quality of highbush blueberries after harvest. The molecular weight of CH had a significant effect on the studied traits. The application of high-molecular-weight CH improved physical characteristics such as the average weight of 100 blueberries, firmness, and puncture. Furthermore, the blueberries had a more intense blue colour; were characterised by a higher content of l-ascorbic acid and polyphenols, especially anthocyanins; and did not contain mycotoxins. Spraying with CH can be recommended in the organic cultivation of highbush blueberries to obtain robust fruit with health-promoting qualities.

INFLUENCE OF INITIAL STATE OF CHITOSAN MEMBRANES ON THEIR SEPARATION PROPERTIES IN PERVAPORATIVE DEHYDRATION

In this study, membranes from chitosan with different molecular weights (175-230 kDa) and degree of deacetylation (92%-98%) were prepared and dehydration of a ethanol-water azeotropic mixture by pervaporation on membranes in the swollen and dry initial state was investigated. The influence of chitosan characteristics and the effect of the initial membrane state on separation properties are discussed. The structure of the obtained membranes changed during the drying process and affected the membrane transport parameters and time to membrane stabilisation. The impact of chitosan characteristics on the transport parameters depended on the initial membrane state. The chitosan molecular weight influenced ethanol transport, whereas the chitosan degree of deacetylation affected water transport. In addition, chitosan with the lowest molecular weight improved the separation properties of the membranes.

Effects of molecular weight of chitosan in a blend with polycaprolactone and grapefruit seed extract for active packaging and biodegradation

Packaging films was developed by melt blending polycaprolactone (PCL) with chitosan as carrier for grapefruit seed extract (GSE). The influence of molecular weight (MW) of chitosan on the biodegradability and antimicrobial efficacy of the blend was investigated. Lower MW chitosan accelerated the release of GSE leading to significant improvement in plasticization, hydrophilicity and inhibition of the growth of Escherichia coli. Albeit it did not change the film morphology as PCL and chitosan remained in immiscible phases. Biodegradation in soil compost over 16 weeks had films with lower MW chitosan demonstrated faster rates of biodegradation with dry weight loss reaching 27 %. This was due to earlier onset of bulk degradation. Interestingly, it was not accompanied by accelerated depolymerisation as all blended films shared similar rates of decline in molecular weight. The formulation of PCL/GSE using lower MW chitosan offers a promising avenue to strengthen biodegradation and antimicrobial efficacy of packaging films.

Reactive oxygen species scavenging nanofibers with chitosan-stabilized Prussian blue nanoparticles for enhanced wound healing efficacy

Chronic inflammatory wounds pose therapeutic challenges in the biomedical field. Polymeric nanofibrous matrices provide extracellular-matrix-like structures to facilitate wound healing; however, wound infection and the subsequent accumulation of reactive oxygen species (ROS) delay healing. Therefore, we herein developed electrospun nanofibers (NFs), composed of chitosan-stabilized Prussian blue (PBChi) nanoparticles (NPs) and poly(vinyl alcohol) (PVA), with ROS scavenging activity to impart antioxidant and wound healing properties. The PBChi NPs were prepared using chitosan with different molecular weights, and their weight ratio with respect to PVA was optimized to yield PBChi-NP-coated PVA NFs with well-defined NF structures. In situ and in vitro antioxidant activity assays showed that the PBChi/PVA NFs could effectively remove ROS. Particularly, PBChi/PVA NFs with a lower chitosan molecular weight exhibited greater antioxidant activity. The hydroxyl radical scavenging activity of PBChi10k/PVA NFs was 60.4 %, approximately two-fold higher than that of PBChi100k/PVA NFs. Further, at the concentration of 10 μg/mL, they could significantly lower the in vitro ROS level by up to 50.7 %. The NFs caused no significant reduction in cell viability, owing to the excellent biocompatibility of PVA with PBChi NPs. Treatment using PBChi/PVA NFs led to faster cell proliferation in in vitro scratch wounds, reducing their size from 202 to 162 μm. The PBChi/PVA NFs possess notable antioxidant and cell proliferation properties as ROS-scavenging wound dressings.

Effects of chitosan molecular weight and deacetylation degree on the properties of collagen‐chitosan composite films for food packaging

AbstractComposite films based on collagen and chitosan with different molecular weights (MWs) and deacetylation degree (DD) are prepared for food packaging. Fourier‐transform infrared analysis indicates that more hydrogen bonds have formed between collagen molecules and chitosan with larger MW or higher DD due to their more reactive groups for interactions. The light barrier capacity, mechanical, and thermal properties of the composite films enhanced with increasing the MW or DD of chitosan. However, composite film with the lowest MW of 50 kDa possesses the best antioxidative and antibacterial activities. Among all the films, composite films containing chitosan with low MW of 50 kDa and high DD of 95% exhibit better preservation effect in pork. The shelf life of pork wrapped with film containing chitosan of 50 kDa has been extended to 3 days with the lowest total volatile basic nitrogen level (12.13 mg/100 g), thiobarbituric acid reactive substance value (0.541 mg malondialdehyde/kg) and total viable count (5.64 log colony forming unit/g). These results indicate that MW and DD of chitosan are two important factors that should be considered when designing collagen‐chitosan composite films for food packaging.

Studies of Protein Wastes Adsorption by Chitosan-Modified Nanofibers Decorated with Dye Wastes in Batch and Continuous Flow Processes: Potential Environmental Applications.

In this study, reactive green 19 dye from wastewater was immobilized on the functionalized chitosan nanofiber membranes to treat soluble microbial proteins in biological wastewater. Polyacrylonitrile nanofiber membrane (PAN) was prepared by the electrospinning technique. After heat treatment, alkaline hydrolysis, and chemically grafted with chitosan to obtain modified chitosan nanofibers (P-COOH-CS), and finally immobilized with RG19 dye, dyed nanofibers were generated (P-COOH-CS-RG19). The synthesis of P-COOH-CS and P-COOH-CS-RG19 are novel materials for protein adsorption that are not deeply investigated currently, with each of the material functions based on their properties in significantly improving the adsorption efficiency. The nanofiber membrane shows good adsorption capacity and great recycling performance, while the application of chitosan and dye acts as the crosslinker in the nanofiber membrane and consists of various functional groups to enhance the adsorption of protein. The dyed nanofibers were applied for the batch adsorption of soluble protein (i.e., lysozyme), and the process parameters including chitosan’s molecular weight, coupling pH, chitosan concentration, dye pH, dye concentration, and lysozyme pH were studied. The results showed that the molecular weight of chitosan was 50 kDa, pH 5, concentration 0.5%, initial concentration of dye at 1 mg/mL dye and pH 12, lysozyme solution at 2 mg/mL at pH 8, and the maximum adsorption capacity was 1293.66 mg/g at a temperature of 318 K. Furthermore, thermodynamic, and kinetic studies suggested that the adsorption behavior of lysozyme followed the Langmuir adsorption isotherm model and the pseudo-second-order kinetic model. The optimal adsorption and desorption conditions based on batch experiments were directly applied to remove lysozyme in a continuous operation. This study demonstrated the potential of dyed nanofibers as an efficient adsorbent to remove approximately 100% of lysozyme from the simulated biological wastewater.

Cytotoxicity Enhancement in MCF-7 Breast Cancer Cells with Depolymerized Chitosan Delivery of α-Mangostin.

The application of α-mangostin (AMG) in breast cancer research has wide intentions. Chitosan-based nanoparticles (CSNPs) have attractive prospects for developing anticancer drugs, especially in their high flexibility for modification to enhance their anticancer action. This research aimed to study the impact of depolymerized chitosan (CS) on the cytotoxicity enhancement of AMG in MCF-7 breast cancer cells. CSNPs effectivity depends on size, shape, crystallinity degree, and charge surface. Modifying CS molecular weight (MW) is expected to influence CSNPs’ characteristics, impacting size, shape, crystallinity degree, and charge surface. CSNPs are developed using the method of ionic gelation with sodium tripolyphosphate (TPP) as a crosslinker and spray pyrolysis procedure. Nanoparticles’ (NPs) sizes vary from 205.3 ± 81 nm to 450.9 ± 235 nm, ZP charges range from +10.56 mV to +51.56 mV, and entrapment efficiency from 85.35% to 90.45%. The morphology of NPs are all the same spherical forms. In vitro release studies confirmed that AMG–Chitosan–High Molecular Weight (AMG–CS–HMW) and AMG–Chitosan–Low Molecular Weight (AMG–CS–LMW) had a sustained-release system profile. MW has a great influence on surface, drug release, and cytotoxicity enhancement of AMG in CSNPs to MCF-7 cancer cells. The preparations AMG–CS–HMW and AMG–CS–LMW NPs considerably enhanced the cytotoxicity of MCF-7 cells with IC50 values of 5.90 ± 0.08 µg/mL and 4.90 ± 0.16 µg/mL, respectively, as compared with the non-nano particle formulation with an IC50 of 8.47 ± 0.29 µg/mL. These findings suggest that CSNPs can enhance the physicochemical characteristics and cytotoxicity of AMG in breast cancer treatment.

Rapid Ultratough Topological Tissue Adhesives.

Tissue adhesives capable of achieving strong and tough adhesion in permeable wet environments are useful in many biomedical applications. However, adhesion generated through covalent bond formation directly with the functional groups of tissues (i.e., COOH and NH2 groups in collagen), or using non-covalent interactions can both be limited by weak, unstable, or slow adhesion. Here, it is shown that by combining pH-responsive bridging chitosan polymer chains and a tough hydrogel dissipative matrix one can achieve unprecedented ultratough adhesion to tissues (>2000Jm-2 ) in 5-10min without covalent bond formation. The strong non-covalent adhesion is shown to be stable under physiologically relevant conditions and strongly influenced by chitosan molecular weight, molecular weight of polymers in the matrix, and pH. The adhesion mechanism relies primarily on the topological entanglement between the chitosan chains and the permeable adherends. To further expand the applicability of the adhesives, adhesion time can be decreased by dehydrating the hydrogel matrix to facilitate rapid chitosan interpenetration and entanglement (>1000Jm-2 in ≤1min). The unprecedented adhesive properties presented in this study open opportunities for new strategies in the development of non-covalent tissue adhesives and numerous bioapplications.

Drying-Induced Surface Wrinkles Generated on Chitosan Films Having Polyion Complex Skin Layers: Effects of Physical Properties of Skin Layers and Substrates on Surface Wrinkling upon Drying

Abstract The effects of the physical properties of skin layers and substrates on drying-induced surface wrinkling are investigated with a system using chitosan films having polyion complex (PIC) skin layers. The PIC layers are fabricated with diverse anionic polymers having similar molecular weights on a chitosan (CS) film surface, and the films are dried. In all cases, surface wrinkles form but their sizes vary widely depending on the molecular structure. In particular, wrinkles formed with ligninsulfonate are much larger than those formed with the others. The skin layers differ significantly in surface hardness but not in thickness, indicating that wrinkle sizes induced by PIC skin layers are predominately determined by the hardness of the layers or by physical properties affected by hardness, such as shrinkage volume. The effects of the elastic moduli and shrinkage volume of the substrates are evaluated with higher molecular weight CS and surface-deacetylated chitin nanofiber composite CS films that have different elastic moduli but show very similar swelling–drying behaviors. The wrinkle sizes and skin layer thicknesses also suggest that wrinkle size in this system depends on the hardness of the skin layers or on the physical properties affecting the hardness.

Analysis of film-forming properties of chitosan with different molecular weights and its adhesion properties with different postharvest fruit surfaces

In this work, the film-forming properties of chitosan with different molecular weights (MW) (30, 100, 200 and 300 kDa) and its adhesion properties with different postharvest fruit surfaces were analyzed. The viscosity of 30 and 300 kDa chitosan film-forming solution gradually increased from 0.007 to 1.16 Pa.s at a shear rate of 10 s−1. Compared to 30 kDa chitosan films, higher MW chitosan films showed enhanced water resistance, water vapor barrier properties and mechanical properties, mainly due to the different strength of interaction forces within the chitosan films, which can be confirmed by microstructural observations and FTIR results of the films. It can be found that different MW chitosan film surfaces with bananas, apples, pears, oranges and strawberries all have a similar adhesion work of about 70–80 mN m−1, and 100 and 200 kDa chitosan film had higher adhesion work with different fruit surfaces compared to 30 and 300 kDa.