β-cyclodextrin chitosan-based hydrogels with tunable pH-responsive properties for controlled release of acyclovir: design, characterization, safety, and pharmacokinetic evaluation

Development and evaluation of a pH-responsive Mimosa pudica seed mucilage/β- cyclodextrin-co-poly(methacrylate) hydrogel for controlled drug delivery: In vitro and in vivo assessment

In this comprehensive investigation, a novel pH-responsive hydrogel system comprising mimosa seed mucilage (MSM), β-cyclodextrin (β-CD), and methacrylic acid (MAA) was developed via free radical polymerization technique to promote controlled drug delivery. The hydrogel synthesis involved strategic variations in polymer, monomer, and crosslinker content in fine-tuning its drug-release properties. The resultant hydrogel exhibited remarkable pH sensitivity, selectively liberating the model drug (Capecitabine = CAP) under basic conditions while significantly reducing release in an acidic environment. Morphological, thermal, and structural analyses proved that CAP has a porous texture, high stability, and an amorphous nature. In vitro drug release experiments showcased a sustained and controlled release profile. Optimum release (85.33 %) results were recorded over 24 h at pH 7.4 in the case of MMB9. Pharmacokinetic evaluation in healthy male rabbits confirmed bioavailability enhancement and sustained release capabilities. Furthermore, rigorous toxicity evaluations and histopathological analyses ensured the safety and biocompatibility of the hydrogel. This pH-triggered drug delivery system can be a promising carrier system for drugs involving frequent administrations.

Biomedical Trends in Stimuli-Responsive Hydrogels with Emphasis on Chitosan-Based Formulations

Biomedicine is constantly evolving to ensure a significant and positive impact on healthcare, which has resulted in innovative and distinct requisites such as hydrogels. Chitosan-based formulations stand out for their versatile utilization in drug encapsulation, transport, and controlled release, which is complemented by their biocompatibility, biodegradability, and non-immunogenic nature. Stimuli-responsive hydrogels, also known as smart hydrogels, have strictly regulated release patterns since they respond and adapt based on various external stimuli. Moreover, they can imitate the intrinsic tissues' mechanical, biological, and physicochemical properties. These characteristics allow stimuli-responsive hydrogels to provide cutting-edge, effective, and safe treatment. Constant progress in the field necessitates an up-to-date summary of current trends and breakthroughs in the biomedical application of stimuli-responsive chitosan-based hydrogels, which was the aim of this review. General data about hydrogels sensitive to ions, pH, redox potential, light, electric field, temperature, and magnetic field are recapitulated. Additionally, formulations responsive to multiple stimuli are mentioned. Focusing on chitosan-based smart hydrogels, their multifaceted utilization was thoroughly described. The vast application spectrum encompasses neurological disorders, tumors, wound healing, and dermal infections. Available data on smart chitosan hydrogels strongly support the idea that current approaches and developing novel solutions are worth improving. The present paper constitutes a valuable resource for researchers and practitioners in the currently evolving field.

Recent Advances of Chitosan-Based Hydrogels for Skin-Wound Dressings

The management of wound healing represents a significant clinical challenge due to the complicated processes involved. Chitosan has remarkable properties that effectively prevent certain microorganisms from entering the body and positively influence both red blood cell aggregation and platelet adhesion and aggregation in the bloodstream, resulting in a favorable hemostatic outcome. In recent years, chitosan-based hydrogels have been widely used as wound dressings due to their biodegradability, biocompatibility, safety, non-toxicity, bioadhesiveness, and soft texture resembling the extracellular matrix. This article first summarizes an overview of the main chemical modifications of chitosan for wound dressings and then reviews the desired properties of chitosan-based hydrogel dressings. The applications of chitosan-based hydrogels in wound healing, including burn wounds, surgical wounds, infected wounds, and diabetic wounds are then discussed. Finally, future prospects for chitosan-based hydrogels as wound dressings are discussed. It is anticipated that this review will form a basis for the development of a range of chitosan-based hydrogel dressings for clinical treatment.

Chitosan-based intelligent polymeric networks for site-specific colon medication delivery: A comprehensive study on controlled release of diloxanide furoate and network formation dynamics

Oral medications are prone to gastric degradation and enzymatic inactivation, diminishing their efficacy. This study investigates a solution by developing intelligent polymeric networks, incorporating chitosan, methacrylic acid, N, N, methylene bisacrylamide, and montmorillonite clay, to enable the controlled release of Diloxanide Furoate (DF), an anti-protozoal drug. Employing a swelling-assisted diffusion technique, drug loading percentages varied from 63.96 % to 76.82 % among different formulations. Increased chitosan and methacrylic acid content enhanced drug loading, while N, N, methylene bisacrylamide and montmorillonite clay demonstrated an inverse relationship affecting diffusion and swelling. Equilibrium swelling studies unveiled formulation-dependent behaviors, with chitosan reducing swelling and methacrylic acid promoting it. Higher N, N, methylene bisacrylamide concentrations decreased swelling, indicating a denser cross-linked structure, while montmorillonite clay reduced hydrophilicity and swelling capacity. Further analyses confirmed successful gel formation, particularly in formulations with higher chitosan, methacrylic acid, and N, N, methylene bisacrylamide content, while montmorillonite clay limited gel fraction due to restricted polymer chain mobility. Techniques such as Fourier transform infrared spectroscopy, Differential scanning calorimetry, and thermal gravimetric analyses supported network development, enhancing thermal stability and cross-linking density. This research underscores the flexibility of polymeric networks for precise drug delivery, offering potential advancements in targeted therapies for various medical conditions.

Quince seed mucilage/β-cyclodextrin/Mmt-Na+-co-poly (methacrylate) based pH-sensitive polymeric carriers for controlled delivery of Capecitabine

In current work, quince seed mucilage and β-Cyclodextrin based pH regulated hydrogels were developed using aqueous free radical polymerization to sustain Capecitabine release patterns and to overcome its drawbacks, such as high dose frequency, short half-life, and low bioavailability. Developed networks were subjected to thermal analysis, Fourier transforms infrared spectroscopy, powder x-ray diffraction, elemental analysis, scanning electron microscopy, equilibrium swelling, and in-vitro release investigations to assess the network system's stability, complexation, morphology, and pH responsiveness. Thermally stable pH-responsive cross-linked networks were formed. Nanocomposite hydrogels were prepared by incorporating Capecitabine-containing clay into the swollen hydrogels. All the formulations exhibited equilibrium swelling ranging from 67.98 % to 92.98 % at pH 7.4. Optimum Capecitabine loading (88.17 %) was noted in the case of hydrogels, while it was 74.27 % in nanocomposite hydrogels. Excellent gel content (65.88 %-93.56 %) was noticed among developed formulations. Elemental analysis ensured the successful incorporation of Capecitabine. Nanocomposite hydrogels released 80.02 % longer than hydrogels after 30 h. NC hydrogels had higher t1/2 (10.57 h), AUC (121.52 μg.h/ml), and MRT (18.95 h) than hydrogels in oral pharmacokinetics. These findings imply that the pH-responsive carrier system may improve Capecitabine efficacy and reduce dosing frequency in cancer therapy. Toxicity profiling proved the system's safety, non-toxicity, and biocompatibility.

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.

A novel pH-responsive hydrogel system based on Prunus armeniaca gum and acrylic acid: Preparation and evaluation as a potential candidate for controlled drug delivery

pH-responsive hydrogels have become effective and attractive materials for the controlled release of drugs at pre-determined destinations. In the present study, a novel hydrogel system based on Prunus armeniaca gum (PAG) and acrylic acid (AA) was prepared by a free radical mechanism using N, N-methylene bisacrylamide (MBA) as cross-linker and potassium persulfate (KPS) as initiator. A series of hydrogels varying PAG, AA, and MBA concentration was developed to determine the impact of these components. Formulated hydrogels were characterized for pH-responsive swelling, drug release, gel content, and porosity. Structural analysis was performed by FTIR, XRD, and SEM analysis. TGA study was applied to assess thermal stability. Oral acute toxicity and in vivo drug release were performed in rabbits. Hydrogels exhibited pH-dependent swelling and drug release. Swelling, drug loading and release, and porosity increased by increasing PAG and AA concentration while decreased by increasing MBA. The gel content of formulations was increased by increasing all three components. FTIR studies confirmed the development of copolymeric networks and the loading of drug. XRD studies revealed that hydrogels were amorphous, and the crystalline drug was changed into an amorphous form during loading. TGA results indicated that hydrogels were stable up to 600 °C. Acute oral toxicity results confirm that hydrogels were nontoxic up to a dose of 2 g/kg body weight in rabbits. The pharmacokinetic evaluation revealed that hydrogels prolonged the availability of the drug and the peak plasma concentration of the drug was obtained in 6 h as compared to the oral solution of the drug. Tramadol hydrochloride (THC) was used as a model drug. Hence, pH-responsive swelling and release, nontoxic nature and improved pharmacokinetics support that PAG-based hydrogels may be considered as potential controlled-release polymeric carriers.

Xanthan-Gum/Pluronic-F-127-Based-Drug-Loaded Polymeric Hydrogels Synthesized by Free Radical Polymerization Technique for Management of Attention-Deficit/Hyperactivity Disorder

Smart and intelligent xanthan gum/pluronic F-127 hydrogels were fabricated for the controlled delivery of atomoxetine HCl. Different parameters such as DSC, TGA, FTIR, XRD, SEM, drug loading, porosity, swelling index, drug release, and kinetics modeling were appraised for the prepared matrices of hydrogels. FTIR confirmed the successful synthesis of the hydrogel, while TGA and DSC analysis indicated that the thermal stability of the reagents was improved after the polymerization technique. SEM revealed the hard surface of the hydrogel, while XRD indicated a reduction in crystallinity of the reagents. High gel fraction was achieved with high incorporated contents of the polymers and the monomer. An increase in porosity, drug loading, swelling, and drug release was observed with the increase in the concentrations of xanthan gum and acrylic acid, whereas Pluronic F-127 showed the opposite effect. A negligible swelling index was shown at pH 1.2 and 4.6 while greater swelling was observed at pH 7.4, indicating a pH-responsive nature of the designed hydrogels. Furthermore, a higher drug release was found at pH 7.4 compared to pH 1.2 and 4.6, respectively. The first kinetics order was followed by the prepared hydrogel formulations. Thus, it is signified from the discussion that smart xanthan gum/pluronic F-127 hydrogels have the potential to control the release of the atomoxetine HCl in the colon for an extended period of time.

Recent Advances in the Pharmaceutical and Biomedical Applications of Cyclodextrin-Capped Gold Nanoparticles

The real problem in pharmaceutical preparation is drugs' poor aqueous solubility, low permeability through biological membranes, and short biological t_1/2. Conventional drug delivery systems are not able to overcome these problems. However, cyclodextrins (CDs) and their derivatives can solve these challenges. This article aims to summarize and review the history, properties, and different applications of cyclodextrins, especially the ability of inclusion complex formation. It also refers to the effects of cyclodextrin on drug solubility, bioavailability, and stability. Moreover, it focuses on preparing and applying gold nanoparticles (AuNPs) as novel drug delivery systems. It also studies the uses and effects of cyclodextrins in this field as novel drug carriers and targeting devices. The system formulated from AuNPs linked with CD molecules combines the advantages of both CD and AuNPs. Cyclodextrins benefit in increasing aqueous drug solubility, loading capacity, stability, and size control of gold NPs. Also, AuNPs are applied as diagnostic and therapeutic agents because of their unique chemical properties. Plus, AuNPs possess several advantages such as ease of detection, targeted and selective drug delivery, greater surface area, high loading efficiency, and higher stability than microparticles. In the present article, we tried to present the potential pharmaceutical applications of CD-derived AuNPs in biomedical applications including antibacterial, anticancer, gene-drug delivery, and various targeted drug delivery applications. Also, the article highlighted the role of CDs in the preparation and improvement of catalytic enzymes, the formation of self-assembling molecular print boards, the fabrication of supramolecular functionalized electrodes, and biosensors formation.

Synthesis, Characterization, Properties, and Biomedical Application of Chitosan-Based Hydrogels

The prospective applications of chitosan-based hydrogels (CBHs), a category of biocompatible and biodegradable materials, in biomedical disciplines such as tissue engineering, wound healing, drug delivery, and biosensing have garnered great interest. The synthesis and characterization processes used to create CBHs play a significant role in determining their characteristics and effectiveness. The qualities of CBHs might be greatly influenced by tailoring the manufacturing method to get certain traits, including porosity, swelling, mechanical strength, and bioactivity. Additionally, characterization methods aid in gaining access to the microstructures and properties of CBHs. Herein, this review provides a comprehensive assessment of the state-of-the-art with a focus on the affiliation between particular properties and domains in biomedicine. Moreover, this review highlights the beneficial properties and wide application of stimuli-responsive CBHs. The main obstacles and prospects for the future of CBH development for biomedical applications are also covered in this review.

Advances in Antiviral Delivery Systems and Chitosan-Based Polymeric and Nanoparticulate Antivirals and Antiviral Carriers

Current antiviral therapy research is focused on developing dosage forms that enable highly effective drug delivery, providing a selective effect in the organism, lower risk of adverse effects, a lower dose of active pharmaceutical ingredients, and minimal toxicity. In this article, antiviral drugs and the mechanisms of their action are summarized at the beginning as a prerequisite background to develop relevant drug delivery/carrier systems for them, classified and briefly discussed subsequently. Many of the recent studies aim at different types of synthetic, semisynthetic, and natural polymers serving as a favorable matrix for the antiviral drug carrier. Besides a wider view of different antiviral delivery systems, this review focuses on advances in antiviral drug delivery systems based on chitosan (CS) and derivatized CS carriers. CS and its derivatives are evaluated concerning methods of their preparation, their basic characteristics and properties, approaches to the incorporation of an antiviral drug in the CS polymer as well as CS nanoparticulate systems, and their recent biomedical applications in the context of actual antiviral therapy. The degree of development (i.e., research study, in vitro/ex vivo/in vivo preclinical testing), as well as benefits and limitations of CS polymer and CS nanoparticulate drug delivery systems, are reported for particular viral diseases and corresponding antivirotics.

Update on Chitosan-Based Hydrogels: Preparation, Characterization, and Its Antimicrobial and Antibiofilm Applications

Chitosan is a prominent biopolymer in research for of its physicochemical properties and uses. Each year, the number of publications based on chitosan and its derivatives increases. Because of its comprehensive biological properties, including antibacterial, antioxidant, and tissue regeneration activities, chitosan and its derivatives can be used to prevent and treat soft tissue diseases. Furthermore, chitosan can be employed as a nanocarrier for therapeutic drug delivery. In this review, we will first discuss chitosan and chitosan-based hydrogel polymers. The structure, functionality, and physicochemical characteristics of chitosan-based hydrogels are addressed. Second, a variety of characterization approaches were used to analyze and validate the physicochemical characteristics of chitosan-based hydrogel materials. Finally, we discuss the antibacterial, antibiofilm, and antifungal uses of supramolecular chitosan-based hydrogels. This review study can be used as a base for future research into the production of various types of chitosan-based hydrogels in the antibacterial and antifungal fields.

Novel Black Seed Polysaccharide Extract-g-Poly (Acrylate) pH-Responsive Hydrogel Nanocomposites for Safe Oral Insulin Delivery: Development, In Vitro, In Vivo and Toxicological Evaluation

Oral delivery of insulin has always been a challenging task due to harsh gut environment involving variable pH and peptidase actions. Currently, no Food and Drug Administration (FDA) approved oral insulin formulation is commercially available, only intravenous (IV) or subcutaneous (SC) routes. Therefore, it is really cumbersome for diabetic patients to go through invasive approaches for insulin delivery on daily basis. In the present study, a novel pH-responsive hydrogel nanocomposite (NC) system was developed and optimized for safe oral delivery of insulin. Black seed polysaccharide extract-based hydrogel (BA hydrogel) was formulated by free radical polymerization and loaded with insulin. Blank BA hydrogel was also incorporated with insulin-loaded montmorillonite nanoclay (Ins-Mmt) to form an Ins-Mmt-BA hydrogel NC and compared with the insulin-loaded hydrogel. Swelling, sol-gel analysis and in vitro release studies proved that Ins-Mmt-BA6 hydrogel NC has the best formulation, with 96.17% maximum insulin released in 24 h. Kinetic modeling applied on insulin release data showed the Korsemeyer-Peppas model (R2 = 0.9637) as the best fit model with a super case II transport mechanism for insulin transport (n > 0.89). Energy Dispersive X-ray (EDX) Spectroscopy, Fourier Transformed Infrared (FTIR) spectroscopy and Powdered X-ray diffraction (PXRD) analysis results also confirmed successful development of a hydrogel NC with no significant denaturation of insulin. Toxicity results confirmed the safety profile and biocompatibility of the developed NC. In vivo studies showed a maximum decrease in blood glucose levels of 52.61% and percentage relative bioavailability (% RBA) of 26.3% for an Ins-Mmt-BA hydrogel NC as compared to BA hydrogels and insulin administered through the SC route.

Recent Advances of Chitosan Formulations in Biomedical Applications

Chitosan, a naturally abundant cationic polymer, is chemically composed of cellulose-based biopolymers derived by deacetylating chitin. It offers several attractive characteristics such as renewability, hydrophilicity, biodegradability, biocompatibility, non-toxicity, and a broad spectrum of antimicrobial activity towards gram-positive and gram-negative bacteria as well as fungi, etc., because of which it is receiving immense attention as a biopolymer for a plethora of applications including drug delivery, protective coating materials, food packaging films, wastewater treatment, and so on. Additionally, its structure carries reactive functional groups that enable several reactions and electrochemical interactions at the biomolecular level and improves the chitosan’s physicochemical properties and functionality. This review article highlights the extensive research about the properties, extraction techniques, and recent developments of chitosan-based composites for drug, gene, protein, and vaccine delivery applications. Its versatile applications in tissue engineering and wound healing are also discussed. Finally, the challenges and future perspectives for chitosan in biomedical applications are elucidated.

From Static to Dynamic: A Review on the Role of Mucus Heterogeneity in Particle and Microbial Transport

Mucus layers (McLs) are on the front line of the human defense system that protect us from foreign abiotic/biotic particles (e.g., airborne virus SARS-CoV-2) and lubricates our organs. Recently, the impact of McLs on human health (e.g., nutrient absorption and drug delivery) and diseases (e.g., infections and cancers) has been studied extensively, yet their mechanisms are still not fully understood due to their high variety among organs and individuals. We characterize these variances as the heterogeneity of McLs, which lies in the thickness, composition, and physiology, making the systematic research on the roles of McLs in human health and diseases very challenging. To advance mucosal organoids and develop effective drug delivery systems, a comprehensive understanding of McLs' heterogeneity and how it impacts mucus physiology is urgently needed. When the role of airway mucus in the penetration and transmission of coronavirus (CoV) is considered, this understanding may also enable a better explanation and prediction of the CoV's behavior. Hence, in this Review, we summarize the variances of McLs among organs, health conditions, and experimental settings as well as recent advances in experimental measurements, data analysis, and model development for simulations.