The Influence of Various Crosslinking Conditions of EDC/NHS on the Properties of Fish Collagen Film.

The process of crosslinking improves the physicochemical properties of biopolymer-based composites, making them valuable for biomedical applications. EDC/NHS-crosslinked collagen materials have a significant potential for tissue engineering applications, due to their enhanced properties and biocompatibility. Chemical crosslinking of samples can be carried out in several ways, which is crucial and has a direct effect on the final properties of the obtained material. In this study, the effect of crosslinking conditions on the properties of collagen films using EDC and NHS was investigated. Studies included FTIR spectroscopy, AFM, swelling and degradation tests, mechanical testing and contact angle measurements. Evaluation of prepared collagen films indicated that both crosslinking agents and crosslinking conditions influenced film properties. Notable alternations were observed in the infrared spectrum of the sample, to which EDC was added directly to the fish collagen solution. The same sample indicated the lowest Young modulus, tensile strength and breaking force parameters and the highest elongation at break. All samples reached the maximum swelling degree two hours after immersion in PBS solution; however, the immersion-crosslinked samples exhibited a significantly lower degree of swelling and were highly durable. The highest roughness was observed for the collagen film crosslinked with EDC, whereas the lowest was observed for the specimen crosslinked with EDC with NHS addition. The crosslinking agents increased the surface roughness of the collagen film, except for the sample modified with the addition of EDC and NHS mixture. All films were characterized by hydrophilic character. The films' modification resulted in a decrease in their hydrophilicity and wettability. Our research allows for a comparison of proposed EDC/NHS crosslinking conditions and their influence on the physicochemical properties of fish collagen thin films. EDC and NHS are promising crosslinking agents for the modification of fish collagen used in biomedical applications.

State of Innovation in Alginate-Based Materials.

This review article presents past and current alginate-based materials in each application, showing the widest range of alginate's usage and development in the past and in recent years. The first segment emphasizes the unique characteristics of alginates and their origin. The second segment sets alginates according to their application based on their features and limitations. Alginate is a polysaccharide and generally occurs as water-soluble sodium alginate. It constitutes hydrophilic and anionic polysaccharides originally extracted from natural brown algae and bacteria. Due to its promising properties, such as gelling, moisture retention, and film-forming, it can be used in environmental protection, cosmetics, medicine, tissue engineering, and the food industry. The comparison of publications with alginate-based products in the field of environmental protection, medicine, food, and cosmetics in scientific articles showed that the greatest number was assigned to the environmental field (30,767) and medicine (24,279), whereas fewer publications were available in cosmetic (5692) and food industries (24,334). Data are provided from the Google Scholar database (including abstract, title, and keywords), accessed in May 2023. In this review, various materials based on alginate are described, showing detailed information on modified composites and their possible usage. Alginate's application in water remediation and its significant value are highlighted. In this study, existing knowledge is compared, and this paper concludes with its future prospects.

Chitosan Based Materials in Cosmetic Applications: A Review.

This review provides a report on the properties and recent advances in the application of chitosan and chitosan-based materials in cosmetics. Chitosan is a polysaccharide that can be obtained from chitin via the deacetylation process. Chitin most commonly is extracted from cell walls in fungi and the exoskeletons of arthropods, such as crustaceans and insects. Chitosan has attracted significant academic interest, as well as the attention of the cosmetic industry, due to its interesting properties, which include being a natural humectant and moisturizer for the skin and a rheology modifier. This review paper covers the structure of chitosan, the sources of chitosan used in the cosmetic industry, and the role played by this polysaccharide in cosmetics. Future aspects regarding applications of chitosan-based materials in cosmetics are also mentioned.

Is Dialdehyde Chitosan a Good Substance to Modify Physicochemical Properties of Biopolymeric Materials?

The aim of this work was to compare physicochemical properties of three dimensional scaffolds based on silk fibroin, collagen and chitosan blends, cross-linked with dialdehyde starch (DAS) and dialdehyde chitosan (DAC). DAS was commercially available, while DAC was obtained by one-step synthesis. Structure and physicochemical properties of the materials were characterized using Fourier transfer infrared spectroscopy with attenuated total reflectance device (FTIR-ATR), swelling behavior and water content measurements, porosity and density observations, scanning electron microscopy imaging (SEM), mechanical properties evaluation and thermogravimetric analysis. Metabolic activity with AlamarBlue assay and live/dead fluorescence staining were performed to evaluate the cytocompatibility of the obtained materials with MG-63 osteoblast-like cells. The results showed that the properties of the scaffolds based on silk fibroin, collagen and chitosan can be modified by chemical cross-linking with DAS and DAC. It was found that DAS and DAC have different influence on the properties of biopolymeric scaffolds. Materials cross-linked with DAS were characterized by higher swelling ability (~4000% for DAS cross-linked materials; ~2500% for DAC cross-linked materials), they had lower density (Coll/CTS/30SF scaffold cross-linked with DAS: 21.8 ± 2.4 g/cm3; cross-linked with DAC: 14.6 ± 0.7 g/cm3) and lower mechanical properties (maximum deformation for DAC cross-linked scaffolds was about 69%; for DAS cross-linked scaffolds it was in the range of 12.67 ± 1.51% and 19.83 ± 1.30%) in comparison to materials cross-linked with DAC. Additionally, scaffolds cross-linked with DAS exhibited higher biocompatibility than those cross-linked with DAC. However, the obtained results showed that both types of scaffolds can provide the support required in regenerative medicine and tissue engineering. The scaffolds presented in the present work can be potentially used in bone tissue engineering to facilitate healing of small bone defects.

Biopolymers for hydrogels in cosmetics: review.

Hydrogels are cross-linked networks of macromolecular compounds characterized by high water absorption capacity. Such materials find a wide range of biomedical applications. Several polymeric hydrogels can also be used in cosmetics. Herein, the structure, properties and selected applications of hydrogels in cosmetics are discussed in general. Detailed examples from scientific literature are also shown. In this review paper, most common biopolymers used in cosmetics are presented in detail together with issues related to skin treatment and hair conditioning. Hydrogels based on collagen, chitosan, hyaluronic acid, and other polysaccharides have been characterized. New trends in the preparation of hydrogels based on biopolymer blends as well as bigels have been shown. Moreover, biopolymer hydrogels employment in encapsulation has been mentioned.

Hyaluronic Acid as a Component of Natural Polymer Blends for Biomedical Applications: A Review.

In this review, we provide a report on recent studies in the field of research on the blends of hyaluronic acid with other natural polymers, namely collagen and chitosan. Hyaluronic acid has attracted significant interest in biomedical and cosmetic applications due to its interesting properties. In recent years, blends of hyaluronic acid with other polymers have been studied for new materials development. New materials may show improved properties that are important in the biomedical applications and in cosmetic preparations. In this review paper, the structure, preparation, and properties of hyaluronic acid blends with collagen and chitosan have been discussed and examples of new materials based on such blends have been presented. A comparison of the currently available information in the field has been shown. Future aspects in the field of hyaluronic acid blends and their applications in the biomedical and cosmetic industry have also been mentioned.

The impact of medicinal brines on microbial biofilm formation on inhalation equipment surfaces.

Materials such as polyvinyl chloride, polypropylene, and polyethylene are used for the construction of medical equipment, including inhalation equipment. Inhalation equipment, because of the wet conditions and good oxygenation, constitutes a perfect environment for microbial biofilm formation. Biofilms may affect microbiological cleanliness of inhalation facilities and installations and promote the development of pathogenic bacteria. Microbial biofilms can form even in saline environments. Therefore, the aim of this study was to evaluate the effect of medicinal brines on microbial biofilm formation on the surfaces of inhalation equipment. The study confirmed the high risk of biofilm formation on surfaces used in inhalation equipment. Isolated microorganisms belonged to potential pathogens of the respiratory system, which can pose a health threat to hospital patients. The introduction of additional contaminants increased the amount of bacterial biofilm. On the other hand, the presence of brines significantly limited the amount of biofilm, thus eliminating the risk of infections.

Phase Behaviour and Miscibility Studies of Collagen/Silk Fibroin Macromolecular System in Dilute Solutions and Solid State.

Miscibility is an important issue in biopolymer blends for analysis of the behavior of polymer pairs through the detection of phase separation and improvement of the mechanical and physical properties of the blend. This study presents the formulation of a stable and one-phase mixture of collagen and regenerated silk fibroin (RSF), with the highest miscibility ratio between these two macromolecules, through inducing electrostatic interactions, using salt ions. For this aim, a ternary phase diagram was experimentally built for the mixtures, based on observations of phase behavior of blend solutions with various ratios. The miscibility behavior of the blend solutions in the miscible zones of the phase diagram was confirmed quantitatively by viscosimetric measurements. Assessing the effects of biopolymer mixing ratio and salt ions, before and after dialysis of blend solutions, revealed the importance of ion-specific interactions in the formation of coacervate-based materials containing collagen and RSF blends that can be used in pharmaceutical, drug delivery, and biomedical applications. Moreover, the conformational change of silk fibroin from random coil to beta sheet, in solution and in the final solid films, was detected by circular dichroism (CD) and Fourier transform infrared spectroscopy (FTIR), respectively. Scanning electron microscopy (SEM) exhibited alterations of surface morphology for the biocomposite films with different ratios. Surface contact angle measurement illustrated different hydrophobic properties for the blended film surfaces. Differential scanning calorimetry (DSC) showed that the formation of the beta sheet structure of silk fibroin enhances the thermal stability of the final blend films. Therefore, the novel method presented in this study resulted in the formation of biocomposite films whose physico-chemical properties can be tuned by silk fibroin conformational changes by applying different component mixing ratios.

Investigation of miscibiliy and physicochemical properties of synthetic polypeptide with collagen blends and their wound healing characteristics.

A suitable condition is needed to foster a rapid recovery of wounds, which is a dynamic and intricate process. The development and characterization of mats of plastic-like peptide polymer (PLP) with collagen for wound healing applications are reported in this work. Viscosity parameters such as the Huggins coefficient [KH], the intrinsic viscosity [η], α by Sun, ∆[η]m by Garcia ∆B and µ suggested by Chee, ∆K, and ß advocated by Jiang and Han, recommend the miscibility of the polypeptide in solution phase. Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray diffraction (XRD) methods in a solid phase. Thermal characteristics using a differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA) showed higher stability for the blends than the pure polymers. The collagen and PLP blends showed exceptional in vitro cytocompatibility, and the in vivo wound-healing studies on the Sprague-Dawley rats demonstrated faster wound healing within two weeks compared to the cotton gauze-treated injuries. Therefore, these membranes can be a possible alternative for treating skin injuries.

Insights into the miscibility characteristics of plastic-mimetic polypeptide with hydroxypropylmethylcellulose: Investigation of thermal degradability and intermolecular interactions.

In this investigation, we integrated the parent recurring sequence of the plastic-derived polypeptide, poly[0.8(AVGVP),0.2(AEGVP)] (A, V, G, P, and E represents Alanine, Valine, Glycine, Proline, and Glutamic acid respectively) followed by characterization with inverse transition temperature, 13C, and 1H-NMR spectroscopy. The miscibility attributes of poly[0.8(AVGVP),0.2(AEGVP)] with Hydroxypropylmethylcellulose was examined both in aqueous and solid-phase. The Huggins' co-efficient [KH], the intrinsic viscosity [η], the interaction parameters ΔB and µ suggested by Chee, ΔK and ß recommended by Jiang and Han, α by Sun, Δ[η]m by Garcia showed that the polypeptide was miscible with HPMC in all proportions. DSC studies revealed single Tg values, and TGA manifested the enhanced thermal stability for all the proportions compared with their individuals. Further, verified the results by SEM and XRD. The FTIR evidenced existence of intermolecular hydrogen bonding between the two constituent polymers that caused the miscible blend system.

Preparation and characterization of collagen/hyaluronic acid/chitosan film crosslinked with dialdehyde starch.

In this work thin film made from the mixture of collagen, hyaluronic acid and chitosan were obtained during solvent evaporation method. The mixtures of biopolymers were modified by dialdehyde starch, which was used as a crosslinking agent. The influence of crosslinking agent on the physico-chemical properties of polymeric matrices was evaluated. The interactions between functional groups of polymers were evaluated by Fourier transform infrared spectroscopy for both unmodified and modified samples. Mechanical properties of film were tested in dry condition using a mechanical testing machine. Morphology of the surface was studied by Atomic Force Microscopy and the roughness parameters were analyzed. Moreover, surface free energy and its polar and dispersive components were evaluated by contact angle measurements. It was found that the addition of dialdehyde starch modified all tested parameters of the studied films. Samples became less elastic and more resist for rupture. Moreover, samples became less rough after crosslinking process and surface free energy increased. Thin film made from the mixture of collagen, hyaluronic acid and chitosan crosslinked with dialdehyde starch can be applied in medicine and in cosmetics.

Chitosan-based electrospun membranes: Effects of solution viscosity, coagulant and crosslinker.

Chitosan-based membranes were prepared via electrospinning technique using a low concentrated acetic acid solution as solvent and poly(ethylene oxide) as co-spinning agent. Different solutions were rheologically characterized and increasing the solution viscosity was found to correspond to a better-defined morphology. The membranes were first subjected to a coagulation process with different baths in order to stabilize chitosan and the mats were found not able to withstand a strongly basic environment. Subsequently, a physical and a chemical crosslinking approach were separately optimized to obtain stable mats whose composition was assessed via thermogravimetric and spectroscopic techniques, proving in both cases the elimination of the co-spinning agent. Above all, the ionically crosslinked mats represent a class of extremely promising biomedical products being probably highly biocompatible and characterized by thin and homogenous nanofibers with a diameter of 200 nm, thus showing the ideal structure to foster cell viability.

Properties of scaffolds based on chitosan and collagen with bioglass 45S5.

Scaffolds based on chitosan (CTS), collagen (Coll) and glycosaminoglycans (GAG) mixtures cross-linked by tannic acid (TA) with bioglass 45S5 addition were obtained with the use of the freeze-drying method. The prepared scaffolds were characterised for morphology, mechanical strength and degradation rate. Moreover, cell viability on the obtained scaffolds was measured with and without the presence of ascorbic acid and dexamethasone. The main purpose of the research was to compare the effectiveness of bioglass 45S5 influence on the physicochemical and biological properties of scaffolds. The results demonstrated that the scaffolds based on the blends of biopolymers cross-linked by TA are stable in an aqueous environment. Scanning electron microscope images allowed the observation of a porous scaffold structure with interconnected pores. The addition of bioglass nanoparticles improved the mechanical properties and decreased the degradation rate of composite materials. The biological properties were improved for 20% tannic acid addition compared to 5%. However, the addition of bioglass 45S5 did not change to cells response significantly.

Drug Release from Porous Matrixes based on Natural Polymers.

BACKGROUND: This review provides a report on recent advances in the field of drug release from matrixes made of natural polymers. Herein, the properties of natural polymers such as proteins and polysaccharides are discussed in general. Selected detailed examples of drug release profiles from biopolymer matrixes have also been collected from scientific literature and practical work, and commented on. In this review, the most common natural polymers, i.e. collagen, elastin, chitosan, hyaluronic acid and sodium alginate have been discussed as biopolymers that can be potentially applied in drug delivery systems. METHODOLOGY: The most rapidly developing field of the biomaterials science is the one dealing with their application as matrixes in drug release systems. Such systems show numerous advantages when compared to conventional ones. They improve medical treatment efficiency due to the fact that drugs are placed directly into the infected part. Moreover, the drug release systems reduce toxic reactions because the drug does not pass through the body and, as a result, does not affect the healthy tissues. Such systems also improve the patient's comfort during the treatment. RESULT: Biocompatibility, bioresorbability and non-toxicity are the significant properties characteristic for natural polymers. Natural polymers can be used to obtain biomaterials which can further find their applications in the production of bones or soft tissues implants as well as dressing materials placed on damaged skin. Nevertheless, the disadvantages of biomaterials made of natural polymers, e.g., high solubility and low thermal stability, limit the range of their potential applications. Therefore, it is necessary to modify material properties by carrying out the cross-linking process. CONCLUSION: Recently, a rapidly growing interest in the use of porous materials as controlled drug delivery matrixes has been observed since they present several positive features. The drug release from polymeric matrixes is based on the carrier degradation process which depends on dissolving and diffusion processes. The selection of a polymeric matrix depends on its compatibility with the drug as well as the manufacturing process which needs to be considered. The proper adjustment of the drug release rate is necessary to obtain the best results during medical treatment. Numerous classes of hydrophilic as well as hydrophobic drugs can be released from polymeric matrixes which is beneficial to medical treatment. The research of different drug release systems has already been carried out, and the results can be found in scientific literature.

Effects of solar radiation on collagen and chitosan films.

Photo-aging and photo-degradation are the deleterious effect of chronic exposure to sun light of many materials made of natural polymers. The resistance of the products on the action of solar radiation is very important for material scientists. The effect of solar radiation on two natural polymers: collagen and chitosan as well as collagen/chitosan blends in the form of thin films has been studied by UV-Vis and FTIR spectroscopy. It was found that UV-Vis spectra, which characterise collagen and collagen/chitosan films, were significantly altered by solar radiation. FTIR spectra of collagen and collagen/chitosan films showed that after solar irradiation the positions of amide A and amide I bands were shifted to lower wavenumbers. There was not any significant alteration of chitosan UV-Vis and FTIR spectra after solar radiation. In the condition of the experiment chitosan films were resistant to the action of solar radiation. The effect of solar UV radiation in comparison to artificial UV radiation has been discussed.

3D composites based on the blends of chitosan and collagen with the addition of hyaluronic acid.

3D porous composites based on blends of chitosan, collagen and hyaluronic acid were obtained through the lyophilization process. Mechanical properties, swelling behavior and thermal stability of the blends were studied. Moreover, SEM images were taken and the structure of the blends was studied. Biological properties of the materials obtained were investigated by analyzing of proliferation rate of fibroblast cells incubated with biomaterial extract using MTT assay (3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide). The results showed that the properties of 3D composites based on the blends of chitosan and collagen were altered after the addition 1%, 2% and 5% of hyaluronic acid. Mechanical properties and thermal stability of chitosan/collagen blends were improved in the presence of hyaluronic acid in the composite. New 3D materials based on the blends of chitosan, collagen and hyaluronic acid were non-toxic and did not significantly affect cell morphology.

Preparation of ready-to-use, stockable and reconstituted collagen.

Collagen is a widely used material in biomedical applications. Although processes that prepare collagen and collagen-based materials that show suitable properties after extraction exist, a ready-to-use, easily stockable, with tailored collagen concentration has not yet been developed. Using rat tail tendons, acid soluble collagen solutions were prepared by two different methods. To improve cell viability of pure collagen films, solutions with physiological pH were also prepared by mixing with NaOH solution. Specimens in the form of thin sheets were then fabricated by solvent evaporation. Next, IR spectroscopy, tensile testing techniques as well as human fibroblast cell morphology and cytotoxicity were used to validate the significant variations in the processes. The results demonstrated that, during the synthesis of collagen stock solution, lyophilization and mechanical blending had little effect on the final properties and therefore offers a method for obtaining solutions with a more homogeneous and modifiable collagen concentration and longer storage time. Neutralizing the stock solution with aqueous NaOH prior to solvent evaporation provided films that had lower mechanical properties but significantly improved biological performance.

Biofilm formation on the surface of polylactide during its biodegradation in different environments.

The research was aimed at determining the abundance and viability of biofilm formed on the surface of polylactide (PLA) during its biodegradation in different environments. It was also aimed at isolating biofilm forming bacteria, determining their hydrolytic activity and taxonomic status. The first step was to evaluate PLA biodegradability in lake water, compost and soil, using OxiTop Control. The next step was to assess the ability of isolated bacteria to form biofilm in the investigated environments and to evaluate the biofilm structure. The results indicate that PLA is sensitive to biodegradation in any environment, particularly in compost. During this process biofilm of high viability was observed on the surface of PLA. Based on the 16S rRNA gene sequence, the biofilm-forming bacteria were classified as the following species: Acidovorax sp. LW9, Chryseobacterium sp. LW2, Aeromonas veronii LW8, Arthrobacter aurescens LG2, Arthrobacter sp. LG12, A. aurescens LG9, Elizabethkingia meningoseptica LK3, A. aurescens LK9, A. aurescens and LK7. The results show that different bacterial species formed biofilm of different abundance and hydrolytic activitiy levels.

Modification by UV radiation of the surface of thin films based on collagen extracted from fish scales.

Collagen was extracted from fish scales (Esox lucius) through demineralization process. Thin films by solvent evaporation from collagen extracted from fish scales were prepared. The surface of thin films made of fish scales collagen was modified by ultraviolet (UV)-irradiation with the wavelength λ = 254 nm. The amino acid composition of the Esox lucius scale collagen was analyzed before and after UV-irradiation by means of high-pressure liquid chromatography. The surface properties of films were investigated using the technique of atomic force microscopy (AFM) and by means of contact angle measurements allowing the calculation of surface free energy. Measurements of the contact angle for diiodomethane (D) and glycerol (G) on the surface of fish collagen films were made and surface free energy was calculated. The structure of collagen before and after UV-irradiation was studied using Fourier-transform infrared spectroscopy. It was found that after UV-irradiation the amount of all amino acids present in collagen molecule decreased. It was found also that the contact angle and the surface free energy were altered by UV-irradiation of collagen film. AFM showed that the surface roughness of collagen films was also altered by UV-irradiation. UV-irradiation caused the decrease of surface roughness due to photochemical processes, which occurred in the top layer of collagen film. The formation of collagen fibrils after solvent evaporation was observed using AFM. The diameter of collagen fibrils was bigger for irradiated collagen film than the diameter of collagen fibrils before UV-irradiation.

Characterization of collagen/hydroxyapatite composite sponges as a potential bone substitute.

Hydroxyapatite and collagen composites (HAp/Col) have the potential in mimicking and replacing skeletal bones. Their combination should prove beneficial for bone tissue engineering due to their natural biological resemblance and properties. In this study, hydroxyapatite and collagen isolated from animal tendons were used in different proportions as composites. Sponges were prepared by freezing and lyophilization of corresponding composite solutions. The properties of composite sponges, such as microstructure, chemical and physical properties were studied. In the present investigation, a collagen sponge and a composite sponge made of composite of HAp/Col were prepared in our lab and characterized by attenuated total reflection Fourier transform infra-red spectroscopy, thermogravimetric analysis and scanning electron microscopy (SEM). Infrared spectroscopy (IR) in combination with attenuated total reflection (ATR) spectroscopy is one of the most widely used technique for surface infrared analysis. The ATR-IR analysis did not indicate shift of the band corresponding to -COO(-) for none of the used HAp/Col ratios. Thermogravimetric results suggested that collagen chains had been embedded with HAp to several complexes with different thermal stabilities. SEM was used to observe the morphology and pore size of the sponges. SEM observations showed the sponges of HAp/Col with fully interconnective macroporosity.