Formulation and Evaluation of Chitosan-Gelatin Thermosensitive Hydrogels Containing 5FU-Alginate Nanoparticles for Skin Delivery

Multi-dynamic-bond cross-linked antibacterial and adhesive hydrogel based on boronated chitosan derivative and loaded with peptides from Periplaneta americana with on-demand removability

The design and development of a bio-adhesive hydrogel with on-demand removability and excellent antibacterial activities are meaningful to achieve high wound closure effectiveness and post-wound-closure care, which is desirable in clinical applications. In this work, a series of adhesive antioxidant antibacterial hydrogels containing peptides from Periplaneta americana (PAP) were prepared through multi-dynamic-bond cross-linking among 3,4-dihydroxybenzaldehyde (DBA) containing catechol and aldehyde groups and chitosan grafted with 3-carboxy-4-fluorophenylboronic acid (CS-FPBA) to enable the effective adhesion of skin tissues and prevention of bacterial infection of wound. PAP was derived from alcohol-extracted residues generated during the pharmaceutical process, aiming to minimize resource wastage and achieve the high-value development of such a medicinal insect. The hydrogel was prepared by freezing-thawing with no toxic crosslinkers. The multi-dynamic-bond cross-linking of dynamic borate ester bonds and dynamic Schiff base bonds can achieve reversible breakage and re-formation and the adhesive strength of CS-FPBA-DBA-P-gel treated with a 20 % glucose solution dramatically decreased from 3.79 kPa to 0.35 kPa within 10 s. Additionally, the newly developed hydrogel presents ideal biocompatibility, hemostasis and antibacterial activity against Staphylococcus aureus and Escherichia coli compared to commercial chitosan gel (approximately 50 % higher inhibition rate), demonstrating its great potential in dealing with infected full-thickness skin wounds.

The Method of Direct and Reverse Phase Portraits as a Tool for Systematizing the Results of Studies of Phase Transitions in Solutions of Thermosensitive Polymers

It is shown that a more than significant amount of experimental data obtained in the field of studying systems based on thermosensitive hydrophilic polymers and reflected in the literature over the past decades makes the issue of their systematization and classification relevant. This, in turn, makes relevant the question of choosing the appropriate classification criteria. It is shown that the basic classification feature can be the number of phase transition stages, which can vary from one to four or more depending on the nature of the temperature-sensitive system. In this work, the method of inverse phase portraits is proposed for the first time. It was intended, among other things, to identify the number of phase transition stages. Moreover, the accuracy of this method significantly exceeds the accuracy of the previously used method of direct phase portraits since, for the first time, the operation of numerical differentiation is replaced by the operation of numerical integration. A specific example of the application of the proposed method for the analysis of a previously studied temperature-sensitive system is presented. It is shown that this method also allows for a quantitative comparison between the results obtained by the differential calorimetry method and the turbidimetry method. Issues related to increasing the resolution of the method of direct phase portraits are discussed.

Intranasal Delivery of Carvedilol- and Quercetin-Encapsulated Cationic Nanoliposomes for Cardiovascular Targeting: Formulation and In Vitro and Ex Vivo Studies

Carvedilol (CVD), an adrenoreceptor blocker, is a hydrophobic Biopharmaceutics Classification System class II drug with poor oral bioavailability due to which frequent dosing is essential to attain pharmacological effects. Quercetin (QC), a polyphenolic compound, is a potent natural antioxidant, but its oral dosing is restricted due to poor aqueous solubility and low oral bioavailability. To overcome the common limitations of both drugs and to attain synergistic cardioprotective effects, we formulated CVD- and QC-encapsulated cationic nanoliposomes (NLPs) in situ gel (CVD/QC-L.O.F.) for intranasal administration. We designed CVD- and QC-loaded cationic nanoliposomal (NLPs) in situ gel (CVD/QC-L.O.F.) for intranasal administration. In vitro drug release studies of CVD/QC-L.O.F. (16.25%) exhibited 18.78 ± 0.57% of QC release and 91.38 ± 0.93% of CVD release for 120 h. Ex vivo nasal permeation studies of CVD/QC-L.O.F. demonstrated better permeation of QC (within 96 h), i.e., 75.09% compared to in vitro drug release, whereas CVD permeates within 48 h, indicating the better interaction between cationic NLPs and the negatively charged biological membrane. The developed nasal gel showed a sufficient mucoadhesive property, good spreadability, higher firmness, consistency, and cohesiveness, indicating suitability for membrane application and intranasal administration. CVD-NLPs, QC-NLPs, and CVD/QC-NLPs were evaluated for in vitro cytotoxicity, in vitro ROS-induced cell viability assessment, and a cellular uptake study using H9c2 rat cardiomyocytes. The highest in vitro cellular uptake of CVD/QC-cationic NLPs by H9c2 cells implies the benefit of QC loading within the CVD nanoliposomal carrier system and gives evidence for better interaction of NLPs carrying positive charges with the negatively charged biological cells. The in vitro H2O2-induced oxidative stress cell viability assessment of H9c2 cells established the intracellular antioxidant activity and cardioprotective effect of CVD/QC-cationic NLPs with low cytotoxicity. These findings suggest the potential of cationic NLPs as a suitable drug delivery carrier for CVD and QC combination for the intranasal route in the treatment of various cardiovascular diseases like hypertension, angina pectoris, etc. and for treating neurodegenerative disorders.

Cross-Linked Alginate Dialdehyde/Chitosan Hydrogel Encompassing Curcumin-Loaded Bilosomes for Enhanced Wound Healing Activity

The current study aimed to fabricate curcumin-loaded bilosomal hydrogel for topical wound healing purposes, hence alleviating the poor aqueous solubility and low oral bioavailability of curcumin. Bilosomes were fabricated via the thin film hydration technique using cholesterol, Span® 60, and two different types of bile salts (sodium deoxycholate or sodium cholate). Bilosomes were verified for their particle size (PS), polydispersity index (PDI), zeta potential (ZP), entrapment efficiency (EE%), and in vitro drug release besides their morphological features. The optimum formulation was composed of cholesterol/Span® 60 (molar ratio 1:10 w/w) and 5 mg of sodium deoxycholate. This optimum formulation was composed of a PS of 246.25 ± 11.85 nm, PDI of 0.339 ± 0.030, ZP of -36.75 ± 0.14 mv, EE% of 93.32% ± 0.40, and the highest percent of drug released over three days (96.23% ± 0.02). The optimum bilosomal formulation was loaded into alginate dialdehyde/chitosan hydrogel cross-linked with calcium chloride. The loaded hydrogel was tested for its water uptake capacity, in vitro drug release, and in vivo studies on male Albino rats. The results showed that the loaded hydrogel possessed a high-water uptake percent at the four-week time point (729.50% ± 43.13) before it started to disintegrate gradually; in addition, it showed sustained drug release for five days (≈100%). In vivo animal testing and histopathological studies supported the superiority of the curcumin-loaded bilosomal hydrogel in wound healing compared to the curcumin dispersion and plain hydrogel, where there was a complete wound closure attained after the three-week period with a proper healing mechanism. Finally, it was concluded that curcumin-loaded bilosomal hydrogel offered a robust, efficient, and user-friendly dosage form for wound healing.

Advances in chitosan-based hydrogels for pharmaceutical and biomedical applications: A comprehensive review

The treatment of diseases, such as cancer, is one of the most significant issues correlated with human beings health. Hydrogels (HGs) prepared from biocompatible and biodegradable materials, especially biopolymers, have been effectively employed for the sort of pharmaceutical and biomedical applications, including drug delivery systems, biosensors, and tissue engineering. Chitosan (CS), one of the most abundant bio-polysaccharide derived from chitin, is an efficient biomaterial in the prognosis, diagnosis, and treatment of diseases. CS-based HGs possess some potential advantages, like high values of bioactive encapsulation, efficient drug delivery to a target site, sustained drug release, good biocompatibility and biodegradability, high serum stability, non-immunogenicity, etc., which made them practical and useful for pharmaceutical and biomedical applications. In this review, we summarize recent achievements and advances associated with CS-based HGs for drug delivery, regenerative medicine, disease detection and therapy.

Multifunctional and theranostic hydrogels for wound healing acceleration: An emphasis on diabetic-related chronic wounds

Hydrogels represent intricate three-dimensional polymeric structures, renowned for their compatibility with living systems and their ability to naturally degrade. These networks stand as promising and viable foundations for a range of biomedical uses. The practical feasibility of employing hydrogels in clinical trials has been well-demonstrated. Among the prevalent biomedical uses of hydrogels, a significant application arises in the context of wound healing. This intricate progression involves distinct phases of inflammation, proliferation, and remodeling, often triggered by trauma, skin injuries, and various diseases. Metabolic conditions like diabetes have the potential to give rise to persistent wounds, leading to delayed healing processes. This current review consolidates a collection of experiments focused on the utilization of hydrogels to expedite the recovery of wounds. Hydrogels have the capacity to improve the inflammatory conditions at the wound site, and they achieve this by diminishing levels of reactive oxygen species (ROS), thereby exhibiting antioxidant effects. Hydrogels have the potential to enhance the growth of fibroblasts and keratinocytes at the wound site. They also possess the capability to inhibit both Gram-positive and Gram-negative bacteria, effectively managing wounds infected by drug-resistant bacteria. Hydrogels can trigger angiogenesis and neovascularization processes, while also promoting the M2 polarization of macrophages, which in turn mitigates inflammation at the wound site. Intelligent and versatile hydrogels, encompassing features such as pH sensitivity, reactivity to reactive oxygen species (ROS), and responsiveness to light and temperature, have proven advantageous in expediting wound healing. Furthermore, hydrogels synthesized using environmentally friendly methods, characterized by high levels of biocompatibility and biodegradability, hold the potential for enhancing the wound healing process. Hydrogels can facilitate the controlled discharge of bioactive substances. More recently, there has been progress in the creation of conductive hydrogels, which, when subjected to electrical stimulation, contribute to the enhancement of wound healing. Diabetes mellitus, a metabolic disorder, leads to a slowdown in the wound healing process, often resulting in the formation of persistent wounds. Hydrogels have the capability to expedite the healing of diabetic wounds, facilitating the transition from the inflammatory phase to the proliferative stage. The current review sheds light on the biological functionalities of hydrogels, encompassing their role in modulating diverse mechanisms and cell types, including inflammation, oxidative stress, macrophages, and bacteriology. Additionally, this review emphasizes the significance of smart hydrogels with responsiveness to external stimuli, as well as conductive hydrogels for promoting wound healing. Lastly, the discussion delves into the advancement of environmentally friendly hydrogels with high biocompatibility, aimed at accelerating the wound healing process.

Chitosan tamarind-based nanoparticles as a promising approach for topical application of curcumin intended for burn healing: in vitro and in vivo study

One of the most prevalent worldwide problems that affect all ages and genders is skin burn. The goal of our study was to assess the ability of curcumin nanoparticles to cure a rat burn model. Three formulations were selected after several tests were performed including investigation of encapsulation efficiency, particle size and zeta potential measurements. In vitro release was achieved on the three selected formulations. The effectiveness of the chosen formulation for healing was evaluated. The induced burn wound was smeared, starting just after excision, once daily with curcumin nanoparticles for 18 days. Our findings revealed that curcumin nanoparticles improved the burn healing potential by augmenting the skin regeneration indices as evidenced by enhancing the new production of hyaluronic acid and collagen type I. Additionally, curcumin nanoparticles could increase levels of vascular endothelial growth factor and alpha smooth muscle activity while drastically reducing the skin's tumour necrosis factor content, revealing a significant potential for burn healing process that is also reflected in the histopathological and immunohistochemical studies. Finally, our results demonstrated that curcumin nanoparticles revealed a significant potential for burn healing than curcumin alone due to its potent antimicrobial, antioxidant and anti-inflammatory properties.

In Vitro and In Vivo Evaluation of Metformin Hydrochloride Hydrogels Developed with Experimental Design in the Treatment of Burns

Burns alter the normal skin barrier and affect various host defense processes that help prevent infections. An ineffective repair process can lead to serious damage, such as the onset of an infection or skin loss, which can then harm the surrounding tissues and ultimately the entire organism. This study aims to prepare in situ gels containing metformin hydrochloride, a compound known for its wound healing properties. To achieve this, in situ gels were prepared using three different gelling agents (Poloxamer 407®, Carbopol 934®, and sodium carboxymethyl cellulose (Na-CMC)) and three different concentrations of metformin hydrochloride (4 mg/g, 6 mg/g, and 8 mg/g), which were optimized through experimental design. Metformin concentration and gelling agent type were independent variables, and the loaded amount and the percentage of metformin released after 150 min were chosen as dependent variables in the optimization process. After determining the optimum values of the dependent variables according to the ANOVA analysis results, in vivo studies were conducted with optimized hydrogel formulations. Two groups, each consisting of seven Wistar rats with a burn model, were treated with metformin-poloxamer 407® gels at doses of 4 mg/g and 8 mg/g for 29 days. The results were then compared to untreated and placebo gel groups. Rats treated with in situ Poloxamer 407® hydrogels containing metformin hydrochloride showed a significant reduction in the size of the burned area after 29 days of treatment. However, for a comprehensive understanding of the wound healing mechanism, further studies such as immuno-histochemical and cell culture studies are needed.

Functionalized chitosan for cancer nano drug delivery

Chitosan is a biotechnological derivative of chitin receiving a widespread pharmaceutical and biomedical applications. It can be used to encapsulate and deliver cancer therapeutics with inherent pH-dependent solubility to confer drug targeting at tumour microenvironment and anti-cancer activity synergizing cancer cytotoxic drug actions. To further reduce the off-target and by-stander adverse effects of drugs, a high targeted drug delivery efficiency at the lowest possible drug doses is clinically required. The chitosan has been functionalized with covalent conjugates or complexes and processed into nanoparticles to encapsulate and control drug release, to avoid premature drug clearance, to deliver drugs passively and actively to cancer site at tissue, cell or subcellular levels, and to promote cancer cell uptake of nanoparticles through membrane permeabilization at higher specificity and scale. Nanomedicine developed using functionalized chitosan translates to significant preclinical improvements. Future challenges related to nanotoxicity, manufacturability, selection precision of conjugates and complexes as a function of cancer omics and their biological responses from administration site to cancer target need critical assessments.

Thermosensitive Hydrogel-Functionalized Mesoporous Silica Nanoparticles for Parenteral Application of Chemotherapeutics

Hydrogels can offer many opportunities for drug delivery strategies. They can be used on their own, or their benefits can be further exploited in combination with other nanocarriers. Intelligent hydrogels that react to changes in the surrounding environment can be utilized as gatekeepers and provide sustained on-demand drug release. In this study, a hybrid nanosystem for temperature- and pH-sensitive delivery was prepared from MCM-41 nanoparticles grafted with a newly synthesized thermosensitive hydrogel (MCM-41/AA-g-PnVCL). The initial particles were chemically modified by the attachment of carboxyl groups. Later, they were grafted with agar (AA) and vinylcaprolactam (VCL) by free radical polymerization. Doxorubicin was applied as a model hydrophilic chemotherapeutic drug. The successful formulation was confirmed by FT-IR and TGA. Transmission electron microscopy and dynamic light scattering analysis showed small particles with negative zeta potential. Their release behaviour was investigated in vitro in media with different pH and at different temperatures. Under tumour simulating conditions (40 °C and pH 4.0), doxorubicin was almost completely released within 72 h. The biocompatibility of the proposed nanoparticles was demonstrated by in vitro haemolysis assay. These results suggest the possible parenteral application of the newly prepared hydrogel-functionalized mesoporous silica nanoparticles for temperature-sensitive and pH-triggered drug delivery at the tumour site.

Design and Study of Nanoceria Modified by 5-Fluorouracil for Gel and Polymer Dermal Film Preparation

In this work we studied nanoceria (CeO2NPs) and nanoceria modified by 5-fluorouracil (5FU) as potential APIs. Nanoceria were synthesized by precipitation in a matrix of hydroxyethyl cellulose or hydroxypropylmethyl cellulose, using cerium (III) nitrate and meglumine. Nanoceria properties were estimated by UV, FTIR and X-ray photoelectron spectra; scanning electron and atomic force microscopy; powder X-ray diffraction patterns and energy dispersive X-ray microanalysis. The cytotoxicity of nanoceria and polymer-protected nanoparticles was evaluated using the established cell line NCTC clone 929 (C3H/An mouse, subcutaneous connective tissue, clone of L. line). The morphology and metabolic activity of nanoparticles at 10 μg∙mL-1 of cells was not significant. In addition, the cytotoxic effects of nanoceria were assessed on two human colorectal cancer cell lines (HT29 and HCT116), murine melanoma B16 cells and normal human skin fibroblasts. An inhibitory effect was shown for HCT116 human colorectal cancer cells. The IC50 values for pure CeO2NPs and CeO2NPs-5FU were 219.0 ± 45.6 μg∙mL-1 and 89.2 ± 14.0 μg∙mL-1, respectively. On the other hand, the IC50 of 5FU in the combination of CeO2NPs-5FU was 2-fold higher than that of pure 5FU, amounting to 5.0 nmol∙mL-1. New compositions of nanoceria modified by 5-fluorouracil in a polymer matrix were designed as a dermal polymer film and gel. The permeability of the components was studied using a Franz cell.

Design and Study of Nanoceria Modified by 5-Fluorouracil for Gel and Polymer Dermal Film Preparation

In this work we studied nanoceria (CeO2NPs) and nanoceria modified by 5-fluorouracil (5FU) as potential APIs. Nanoceria were synthesized by precipitation in a matrix of hydroxyethyl cellulose or hydroxypropylmethyl cellulose, using cerium (III) nitrate and meglumine. Nanoceria properties were estimated by UV, FTIR and X-ray photoelectron spectra; scanning electron and atomic force microscopy; powder X-ray diffraction patterns and energy dispersive X-ray microanalysis. The cytotoxicity of nanoceria and polymer-protected nanoparticles was evaluated using the established cell line NCTC clone 929 (C3H/An mouse, subcutaneous connective tissue, clone of L. line). The morphology and metabolic activity of nanoparticles at 10 μg∙mL−1 of cells was not significant. In addition, the cytotoxic effects of nanoceria were assessed on two human colorectal cancer cell lines (HT29 and HCT116), murine melanoma B16 cells and normal human skin fibroblasts. An inhibitory effect was shown for HCT116 human colorectal cancer cells. The IC50 values for pure CeO2NPs and CeO2NPs-5FU were 219.0 ± 45.6 μg∙mL−1 and 89.2 ± 14.0 μg∙mL−1, respectively. On the other hand, the IC50 of 5FU in the combination of CeO2NPs-5FU was 2-fold higher than that of pure 5FU, amounting to 5.0 nmol∙mL−1. New compositions of nanoceria modified by 5-fluorouracil in a polymer matrix were designed as a dermal polymer film and gel. The permeability of the components was studied using a Franz cell.

Eco-friendly chitosan-based nanostructures in diabetes mellitus therapy: Promising bioplatforms with versatile therapeutic perspectives

Nature-derived polymers, or biopolymers, are among the most employed materials for the development of nanocarriers. Chitosan (CS) is derived from the acetylation of chitin, and this biopolymer displays features such as biocompatibility, biodegradability, low toxicity, and ease of modification. CS-based nano-scale delivery systems have been demonstrated to be promising carriers for drug and gene delivery, and they can provide site-specific delivery of cargo. Owing to the high biocompatibility of CS-based nanocarriers, they can be used in the future in clinical trials. On the other hand, diabetes mellitus (DM) is a chronic disease that can develop due to a lack of insulin secretion or insulin sensitivity. Recently, CS-based nanocarriers have been extensively applied for DM therapy. Oral delivery of insulin is the most common use of CS nanoparticles in DM therapy, and they improve the pharmacological bioavailability of insulin. Moreover, CS-based nanostructures with mucoadhesive features can improve oral bioavailability of insulin. CS-based hydrogels have been developed for the sustained release of drugs and the treatment of DM complications such as wound healing. Furthermore, CS-based nanoparticles can mediate delivery of phytochemicals and other therapeutic agents in DM therapy, and they are promising compounds for the treatment of DM complications, including nephropathy, neuropathy, and cardiovascular diseases, among others. The surface modification of nanostructures with CS can improve their properties in terms of drug delivery and release, biocompatibility, and others, causing high attention to these nanocarriers in DM therapy.

Editorial on the Special Issue "Chitosan Functional Hydrogels: Synthesis and Applications"

Chitin, a polysaccharide composed of β-(1-4)-linked 2-deoxy-2-acetamido-d-glucose units, is found in cell walls of different organisms, including crustaceans, fungi, insects, some algae, microorganisms, and some invertebrate animals, and its deacetylation into chitosan confers it with incredible chemical versatility allowing it to be processed into numerous products [...].

Microneedle-Assisted Topical Delivery of Idebenone-Loaded Bioadhesive Nanoparticles Protect against UV-Induced Skin Damage

Ultraviolet (UV) radiation can penetrate the basal layer of the skin and induce profound alterations in the underlying dermal tissues, including skin pigmentation, oxidative stress, photoaging, glycation, and skin cancer. Idebenone (IDB), an effective antioxidant that suppresses melanin biosynthesis and glycation, can protect the skin from UV-induced damage, accounting for its use in commercial anti-aging formulations. Ideally, IDB formulations should retain IDB inside the skin for a sufficient period, despite disturbances such as sweating or swimming. Herein, we present an IDB topical formulation based on Tris (tris(hydroxymethyl)-aminomethane)-modified bioadhesive nanoparticles (Tris-BNPs) and microneedle-assisted delivery. We found that Tris-BNPs loaded with IDB (IDB/Tris-BNPs) effectively reached the basal layer of the skin and were retained for at least 4 days with a slow and continuous drug release profile, unlike non-bioadhesive nanoparticles (NNPs) and bioadhesive nanoparticles (BNPs) of similar sizes (ranging from 120-142 nm) and zeta-potentials (above -20 mV), which experienced a significant reduction in concentration within 24 h. Notably, IDB/Tris-BNPs showed superior performance against UV-induced damage relative to IDB/NNPs and IDB/BNPs. This effect was demonstrated by lower levels of reactive oxygen species and advanced glycation end-products in skin tissues, as well as suppressed melanogenesis. Therefore, the proposed IDB delivery strategy provided long-term protective effects against UV-induced skin damage.

Gel Formulations for Topical Treatment of Skin Cancer: A Review

Skin cancer, with all its variations, is the most common type of cancer worldwide. Chemotherapy by topical application is an attractive strategy because of the ease of application and non-invasiveness. At the same time, the delivery of antineoplastic agents through the skin is difficult because of their challenging physicochemical properties (solubility, ionization, molecular weight, melting point) and the barrier function of the stratum corneum. Various approaches have been applied in order to improve drug penetration, retention, and efficacy. This systematic review aims at identifying the most commonly used techniques for topical drug delivery by means of gel-based topical formulations in skin cancer treatment. The excipients used, the preparation approaches, and the methods characterizing gels are discussed in brief. The safety aspects are also highlighted. The combinatorial formulation of nanocarrier-loaded gels is also reviewed from the perspective of improving drug delivery characteristics. Some limitations and drawbacks in the identified strategies are also outlined and considered within the future scope of topical chemotherapy.

Bentonite- and Palygorskite-Based Gels for Topical Drug Delivery Applications

Bentonite or palygorskite-based hydrogels have recently been suggested as a strategy to increase bioavailability and control the retention and release of therapeutic candidates. In this work, clay-based hydrogels loaded with diclofenac acid nanocrystals have been successfully designed and developed. The aim was to improve diclofenac solubility, its dissolution rate and to enhance its local bioavailability after topical application. For this purpose, diclofenac acid nanocrystals were prepared by wet media milling technology and then loaded into inorganic hydrogels based on bentonite and/or palygorskite. Diclofenac acid nanocrystals were characterized by morphology, size, and zeta potential. Moreover, rheological behavior, morphology, solid state, release studies, and in vitro skin penetration/permeation of diclofenac acid nanocrystals-loaded hydrogels were performed. The hydrogels were characterized by a crystalline structure, and demonstrated that the inclusion of diclofenac in clay-based hydrogels resulted in an increased thermal stability. The presence of both palygorskite and bentonite reduced nanocrystal mobility, and consequently its release and penetration into the skin. On the other hand, bentonite- or palygorskite-based hydrogels revealed great potential as an alternative strategy to enhance topical bioavailability of DCF nanocrystals, enhancing their penetration to the deeper skin layers.

Silver Nanoparticles and Glycyrrhiza glabra (Licorice) Root Extract as Modifying Agents of Hydrogels Designed as Innovative Dressings

The interest in the application of plant extracts as modifiers of polymers intended for biomedical purposes is constantly increasing. The therapeutical properties of the licorice root, including its anti-inflammatory and antibacterial activity, make this plant particularly promising. The same applies to silver nanoparticles showing antibacterial properties. Thus the main purpose of the research was to design hydrogel dressings containing both licorice root extract and nanosilver so as to obtain a system promoting wound regeneration processes by preventing infection and inflammation within the wound. The first step included the preparation of the plant extract via the solid-liquid extraction using the Soxhlet extractor and the synthesis of silver nanoparticles by the chemical reduction of silver ions using a sodium borohydride as a reducing agent. Subsequently, hydrogels were synthesized via photopolymerization and subjected to studies aiming at characterizing their sorption properties, surface morphology via scanning electron microscopy, and their impact on simulated physiological liquids supported by defining these liquids' influence on hydrogels' structures by FT-IR spectroscopy. Next, the tensile strength of hydrogels and their percentage elongation were determined. Performed studies also allowed for determining the hydrogels' wettability and free surface energies. Finally, the cytotoxicity of hydrogels towards L929 murine fibroblasts via the MTT reduction assay was also verified. It was demonstrated that developed materials showed stability in simulated physiological liquids. Moreover, hydrogels were characterized by high elasticity (percentage elongation within the range of 24-29%), and their surfaces were hydrophilic (wetting angles below 90°). Hydrogels containing both licorice extract and nanosilver showed smooth and homogeneous surfaces. Importantly, cytotoxic properties towards L929 murine fibroblasts were excluded; thus, developed materials seem to have great potential for application as innovative dressings.

Gelatin and Chitosan as Meat By-Products and Their Recent Applications

Meat by-products such as bones, skin, horns, hooves, feet, skull, etc., are produced from slaughtered mammals. Innovative solutions are very important to achieving sustainability and obtaining the added value of meat by-products with the least impact on the environment. Gelatin, which is obtained from products high in collagen, such as dried skin and bones, is used in food processing, and pharmaceuticals. Chitosan is derived from chitin and is well recognized as an edible polymer. It is a natural product that is non-toxic and environmentally friendly. Recently, chitosan has attracted researchers' interests due to its biological activities, including antimicrobial, antitumor, and antioxidant properties. In this review, article, we highlighted the recent available information on the application of gelatin and chitosan as antioxidants, antimicrobials, food edible coating, enzyme immobilization, biologically active compound encapsulation, water treatment, and cancer diagnosis.

Healing Efficacy of Hesperetin-Containing Chitosan Gel in Burn Wound: Formulation Design and In Vivo Evaluation

More than 5 million people require medical attention due to burn-related injuries annually. Significant research has been carried out in recent decades to develop approaches to improve the healing of burn wounds. The focus has also been on the development of natural product-based therapeutic remedies for the treatment of burn wounds. This has been done primarily due to multimodal mechanisms exhibited by some promising bioactive molecules of natural origin. Hesperetin is one such molecule that possesses strong anti-inflammatory and antioxidant properties. It is mainly obtained from citrus species. The goal of the current study was to assess how well chitosan gel that contains hesperetin may cure burn wounds. The advantage of using chitosan gel is that it could form a depot at the site and provide a protective therapeutic covering over burn wounds. In the present study, hesperetin-containing chitosan gel was prepared and evaluated for percentage hesperetin content, extrudability, spreadability, and rheological behavior. The preclinical wound healing activity was evaluated using an experimental burn wound model in Wistar rats. The results of the animal experiment showed early and better healing of burn wounds in animals treated with hesperetin-containing chitosan gel. There was 92.79% healing after 14 days of application of hesperetin-containing chitosan gel compared to 69.49% healing observed in the control group. Further, the histopathological evaluation suggested no inflammatory cell infiltration, normal epidermal growth, and normal collagen bundle arrangement in these animals. Overall the results provide proof of concept to establish the wound healing potential of hesperetin-containing chitosan gel against burn wounds.

Magnetic Application of Gadolinium Orthoferrite Nanoparticles Synthesized by Sol–Gel Auto-Combustion Method

In this manuscript, we present the synthesis of gadolinium orthoferrite nanoparticles using the sol–gel auto-combustion technique. The obtained gadolinium orthoferrite nanoparticles were annealed at various temperatures, such as 800 °C, 900 °C, 1000 °C, and 1100 °C. The synthesized materials were analyzed by various instrumental characterizations. The vibrational characteristics of the synthesized samples were verified by FTIR. The surface morphology of the gadolinium orthoferrite nanoparticles was analyzed by FE-SEM and HR-TEM, revealing their spherical structural morphology and uniform particle structure. The presence of the elemental features was analyzed in the gadolinium orthoferrite nanoparticles by EDAX. The surface analysis of the core ranges of the XPS-recorded spectra were obtained for the elemental states of the Gd, Fe, and O factors in the samples, and it additionally characterized the different levels of oxidative states by fitting the levels of the high-resolution parameters of Gd 4d, Fe 2p, and O 1s. The magnetic properties of the samples were investigated by VSM. The measurement of the magnetic parameters revealed that gadolinium orthoferrite nanoparticles exhibit a ferromagnetic nature.