Development and characterization of pH-sensitive chondroitin sulfate-co-poly(acrylic acid) hydrogels for controlled release of diclofenac sodium

Development and Optimization of Stimuli-Responsive Fenugreek/Carrageenan-Co-poly (Methacrylate) Hydrogel Matrices for Controlled Delivery of 5-Fluorouracil

This study developed novel, stimuli-responsive, biocompatible fenugreek/carrageenanco-poly(methacrylate) hydrogels via free radical polymerization for pH-regulated 5-FU delivery. The hydrogels were evaluated for drug loading (75.2-96.39%), swelling kinetics, sol-gel fraction, electrolyte responsiveness, porosity, and in vitro drug release. Analytical techniques (FTIR, SEM, PXRD, DSC/TGA) confirmed hydrogel formation, drug-excipient compatibility, and thermal stability. FTIR verified cross-linking and 5-FU incorporation, while DSC/TGA and PXRD indicated reduced drug crystallinity and transition to an amorphous form. SEM revealed rough surfaces with porous networks, supporting high drug loading. The hydrogels exhibited pH-responsive swelling, with higher swelling at pH 7.4 (following second-order kinetics) and minimal swelling at pH 1.2. They also responded to monovalent and divalent cations. In vitro release at pH 7.4 showed controlled 5-FU delivery (68.40-96.81%) over 36 h, following non-Fickian diffusion and Higuchi kinetics. Acute oral toxicity studies confirmed biocompatibility and safety. These findings demonstrate that fenugreek/carrageenan-co-poly(methacrylate) hydrogels are promising biocompatible carriers for targeted, controlled 5-FU delivery, offering a safer option for colorectal cancer treatment and other chemotherapy regimens.

Fabrication and evaluation of chondroitin sulfate based hydrogels loaded with chitosan nanoparticles for oral delivery of vildagliptin

Vildagliptin is a drug of choice in type II diabetes mellitus that suffers from limitations like short half-life with reduced bioavailability. To improve the therapeutic performance of vildagliptin, this study aimed to synthesize chitosan nanoparticles (NPs) loaded hydrogel by using biological polysaccharides like sodium alginate (SA) and chondroitin sulfate (CS). The NPs were prepared by ionic gelation method and various characterization tests like surface morphology, size and zeta potential, entrapment efficiency, and in-vitro drug release studies were performed. Results indicated that NPs were round in geometry with an average particle size of 213 nm, having drug encapsulation efficiency of 65 % and controlled drug release within 6-8 h. The optimized NPs (F2) loaded hydrogel showed a good dynamic swelling with gel fraction of 96 %. The hydrogels released 96 % of vildagliptin in 72 h via a non-Fickian diffusion mechanism. The optimized formulation was thermally stable. Formulation showed greater swelling at slight basic pH 7.4 as compared to acidic medium. Moreover, acute toxicity study results demonstrated that the developed NPs loaded hydrogel were safe for oral delivery. The overall results suggested that vildagliptin-loaded NPs loaded hydrogel can serve as an alternative novel dosage form for oral controlled drug delivery.

Efficacy of chondroitin sulfate as an emerging biomaterial for cancer-targeted drug delivery: A short review

The global increase in cancer incidence over the past decade highlights the urgent need for more effective therapeutic strategies. Conventional cancer treatments face challenges such as drug resistance and off-target toxicity, which affect healthy tissues. Chondroitin sulfate (CHDS), a naturally occurring bioactive macromolecule, has gained attention because of its biocompatibility, biodegradability, and low toxicity, positioning it as an ideal candidate for cancer-targeted drug delivery systems. This review highlights the potential of CHDS as an emerging biomaterial in cancer therapy, focusing on its unique biological properties and applications in drug delivery platforms. Furthermore, we discuss the advantages of CHDS-based biomaterials in enhancing cancer treatment efficacy and minimizing side effects, in order to provide a comprehensive reference for future research on CHDS-based cancer therapeutics.

Essential oils loaded carboxymethylated Cassia fistula gum-based novel hydrogel films for wound healing

Carboxymethylated Cassia fistula gum (CCFG) and citric acid (CA) based wound healing film, (CCFG-CA) was developed using the solvent casting method. Glycerol was added as a plasticizing agent. The synthesized Carboxymethylated Cassia fistula gum cross-linked citric acid based hydrogel film (CCFG-CA) was evaluated morphologically, thermally, and structurally using FESEM, TGA, XRD and FTIR. Three essential oils (EO), rosemary (Rosmarinus officinalis), turmeric (Curcuma longa) and thuja (Thuja occidentalis L), known for antimicrobial and antioxidant activities, were loaded into the CCFG-CA film to develop essential oils loaded carboxymethylated Cassia fistula gum cross-linked citric acid based hydrogel film (CCFG-CA-EO). In vitro studies (MTT assay, disk diffusion assay, permeability tests and DPPH assay) confirm the biocompatibility, anti-oxidant and anti-microbial properties of the CCFG-CA-EO film. In vivo (wound healing studies on wistar rats and their histology) shows 99 % of wound healing and re-epithelialization in 14 days. Degradability (within 15 days), protein adsorption (12.05 μg/mL) and contact angle determination (69.43°ׄׄ ± 0.48) tests confirmed the potential of CCFG-CA-EO as an effective wound-healing material.

Tailoring pH-sensitive carboxymethyl tamarind kernel gum-based hydrogel for an efficient delivery of hydrophobic drug indomethacin

Polyacrylamide hydrogels have gained attention in the drug delivery field for their pH-dependent nature. Nevertheless, their limited degradability and lower entrapment efficiency for hydrophobic drugs hinder their utility in controlled drug release. This research aims to design a degradable pH-sensitive hydrogel for delivering the hydrophobic drug indomethacin to the colon. This work developed and optimized the hydrogels based on β-cyclodextrin, carboxymethyl tamarind kernel gum, and polyacrylamide with varying amounts of polyethylene glycol diacrylate. The optimized hydrogel exhibits 76.52 % gel fraction, 89.21 % porosity, 1000.27 % swelling, and 90.0 % equilibrium water content. The hydrogel was characterized using Attenuated Total Reflection-Fourier Transform Infrared spectroscopy, confirming the successful crosslinking of the synthesized hydrogel. Powder X-ray Diffraction revealed their amorphous nature while Scanning Electron Microscopy showed a porous surface morphology of the hydrogel. Moreover, rheology confirmed the hydrogel's elastic nature. Notably, the hydrogel demonstrated a drug release of 60.26 % at pH 7.4. Kinetic modelling of indomethacin release data indicated a Fickian diffusion release mechanism. Cytotoxicity tests on HCT-116 cells showed 79 % viability, and the hydrogel fully degraded within 10 days. These results confirmed the potential of synthesized β-CD/PAM/CMTKG hydrogel for controlled indomethacin delivery to the colon.

Acrylated adhesive proteinic microneedle patch for local drug delivery and stable device implantation

Microneedle patches have been developed as favorable platforms for delivery systems, such as the locoregional application of therapeutic drugs, and implantation systems, such as electronic devices on visceral tissue surfaces. However, the challenge lies in finding materials that can achieve both biocompatibility and stable fixation on the target tissue. To address this issue, utilizing a biocompatible adhesive biomaterial allows the flat part of the patch to adhere as well, enabling double-sided adhesion for greater versatility. In this work, we propose an adhesive microneedle patch based on mussel adhesive protein (MAP) with enhanced mechanical strength via ultraviolet-induced polyacrylate crosslinking and Coomassie brilliant blue molecules. The strong wet tissue adhesive and biocompatible nature of engineered acrylated-MAP resulted in the development of a versatile wet adhesive microneedle patch system for in vivo usage. In a mouse tumor model, this microneedle patch effectively delivered anticancer drugs while simultaneously sealing the skin wound. Additionally, in an application of rat subcutaneous implantation, an electronic circuit was stably anchored using a double-sided wet adhesive microneedle patch, and its signal location underneath the skin did not change over time. Thus, the proposed acrylated-MAP-based wet adhesive microneedle patch system holds great promise for biomedical applications, paving the way for advancements in drug delivery therapeutics, tissue engineering, and implantable electronic medical devices.

Simultaneous Rosiglitazone Release and Low-Density Lipoprotein Removal by Chondroitin Sodium Sulfate/Cyclodextrin/Poly(acrylic acid) Composite Adsorbents for Atherosclerosis Therapy

Atherosclerosis (AS) is characterized by the accumulation of substantial low-density lipoprotein (LDL) and inflammatory response. Hemoperfusion is commonly employed for the selective removal of LDL from the body. However, conventional hemoperfusion merely focuses on LDL removal and does not address the symptom of plaque associated with AS. Based on the LDL binding properties of acrylated chondroitin sodium sulfate (CSA), acrylated beta-cyclodextrin (CD) and acrylic acid (AA), along with the anti-inflammatory property of rosiglitazone (R), the fabricated AA-CSA-CD-R microspheres could simultaneously release R and facilitate LDL removal for hemoperfusion. The AA and CSA offer electrostatic adsorption sites for LDL, while the CD provides hydrophobic adsorption sites for LDL and weak binding sites for R. According to the Sips model, the maximum static LDL adsorption capacity of AA-CSA-CD-R is determined to be 614.73 mg/g. In dynamic simulated perfusion experiments, AA-CSA-CD-R exhibits an initial cycle LDL adsorption capacity of 150.97 mg/g. The study suggests that the weakened inflammatory response favors plaque stabilization. The anti-inflammatory property of the microspheres is verified through an inflammation model, wherein the microsphere extracts are cocultured with mouse macrophages. Both qualitative analysis of iNOS\TNF-α and quantitative analysis of IL-6\TNF-α collectively demonstrate the remarkable anti-inflammatory effect of the microspheres. Therefore, the current study presents a novel blood purification treatment of eliminating pathogenic factors and introducing therapeutic factors to stabilize AS plaque.

Formulation and In Vitro Assessment of Polymeric pH-Responsive Nanogels of Chitosan for Sustained Delivery of Madecassoside

Madecassoside, a triterpenoid saponin compound mainly isolated from the gotu kola herb (Centella asiatica), shows an extensive range of biological activities, including antiapoptotic, antioxidant, anti-inflammatory, moisturizing, neuroprotective, and wound healing effects. It has been highly used in the management of eczema, skin wounds, and other diseases. Due to poor oral bioavailability, membrane permeability, and intestinal absorption, the clinical application of the madecassoside is limited. Hence, a drug carrier system is needed that not only sustains the release of the madecassoside but also overcomes the drawbacks associated with its administration. Therefore, the authors prepared novel pH-responsive chitosan-based nanogels for the sustained release of madecassoside. Free radical polymerization technique was used for cross-linking of polymer chitosan and monomer methacrylic acid in the presence of cross-linker N',N'-methylene bis(acrylamide). The decrease in polymer crystallinity after polymerization and development of nanogels was demonstrated by XRD and FTIR analysis. The effects of nanogel contents on polymer volume, sol-gel analysis, swelling, drug loading, and release were investigated. Results indicated that high swelling and maximum release of the drug occurred at pH 7.4 compared to pH 1.2 and 4.6, indicating the excellent pH-sensitive nature of the engineered nanogels. High swelling and drug release were perceived with the integration of a high quantity of chitosan, while a decline was observed with the high integration of N',N'-methylene bis(acrylamide) and methacrylic acid contents. The same effects of nanogel contents were shown for drug loading too. Sol fraction was reduced, while gel fraction was enhanced by increasing the chitosan load, N',N'-methylene bis(acrylamide), and methacrylic acid. The Korsmeyer-Peppas model of kinetics was trailed by all nanogel formulations with non-Fickian diffusion. The results demonstrated that prepared nanogels can be employed for sustained release of the madecassoside.

Superabsorbent hydrogels based on natural polysaccharides: Classification, synthesis, physicochemical properties, and agronomic efficacy under abiotic stress conditions: A review

Superabsorbent polymers (SAPs) are a class of polymers that have attracted tremendous interest due to their multifunctional properties and wide range of applications. The importance of this class of polymers is highlighted by the large number of publications, including articles and patents, dealing with the use of SAPs for various applications. Within this framework, this review provides an overview of SAPs and highlights various key aspects, such as their history, classification, and preparation methods, including those related to chemically or physically cross-linked networks, as well as key factors affecting their performance in terms of water absorption and storage. This review also examines the potential use of polysaccharides-based SAPs in agriculture as soil conditioners or slow-release fertilizers. The basic aspects of SAPs, and methods of chemical modification of polysaccharides are presented and guidelines for the preparation of hydrogels are given. The water retention and swelling mechanisms are discussed in light of some mathematical empirical models. The nutrient slow-release kinetics of nutrient-rich SAPs are also examined on the basic of commonly used mathematical models. Some examples illustrating the advantages of using SAPs in agriculture as soil conditioners and agrochemical carriers to improve crop growth and productivity are presented and discussed. This review also attempts to provide an overview of the role of SAPs in mitigating the adverse effects of various abiotic stresses, such as heavy metals, salinity, and drought, and outlines future trends and prospects.

pH-sensitive bilayer electrospun nanofibers based on ethyl cellulose and Eudragit S-100 as a dual delivery system for treatment of the burn wounds; preparation, characterizations, and in-vitro/in-vivo assessment

A pH-sensitive bilayer electrospun nanofibrous mat containing both antibiotic (gentamicin sulfate, GEN) and non-steroidal anti-inflammatory (diclofenac sodium, DIC) drugs was fabricated for burn wound dressing by electrospinning technique, in which ethyl cellulose (EC) and ethyl cellulose/Eudragit S-100 (EC/ES-100) formed the top and bottom layers, respectively. The fabricated pH-sensitive bilayer electrospun nanofibrous mats were characterized from aspects of both structure and efficiency. Physicochemical properties were investigated via SEM, FTIR, and TGA. The swelling ratio and in vitro drug release of the fabricated nanofibrous mats were studied in different pHs. MTT was applied to assess the safety of the fiber mats. Finally, the in vivo efficiency of the designed pH-sensitive bilayer electrospun nanofibrous mats was examined on the male Wistar rats. Based on the histological analysis and wound healing test (in vivo animal experiments), the (ES100/EC-DIC/GEN)-(EC) pH-sensitive bilayer nanofibrous mat displayed faster wound healing than other bilayer nanofibrous mat. As a result, (ES100/EC-DIC/GEN)-(EC) bilayer nanofibrous mat with pH-responsion could accelerate the burn wound healing process via decreasing the adverse effects of GEN and DIC as topical antimicrobial and anti-inflammatory agents, receptively.

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.

Synthesis and Evaluation of Alginate-Based Nanogels as Sustained Drug Carriers for Caffeine

The objective of this study is to design a polymeric network of nanogels for sustained release of caffeine. Therefore, alginate-based nanogels were fabricated by a free-radical polymerization technique for the sustained delivery of caffeine. Polymer alginate was crosslinked with monomer 2-acrylamido-2-methylpropanesulfonic acid by crosslinker N',N'-methylene bisacrylamide. The prepared nanogels were subjected to sol-gel fraction, polymer volume fraction, swelling, drug loading, and drug release studies. A high gel fraction was seen with the increasing feed ratio of polymer, monomer, and crosslinker. Greater swelling and drug release were observed at pH 4.6 and 7.4 as compared to pH 1.2 due to the deprotonation and protonation of functional groups of alginate and 2-acrylamido-2-methylpropanesulfonic acid. An increase was observed in swelling, loading, and release of the drug with the incorporation of a high feed ratio of polymer and monomer, while a reduction was seen with the increase in crosslinker feed ratio. Similarly, an HET-CAM test was used to evaluate the safety of the prepared nanogels, which showed that the prepared nanogels have no toxic effect on the chorioallantoic membrane of fertilized chicken eggs. Similarly, different characterizations techniques such as FTIR, DSC, SEM, and particle size analysis were carried out to determine the development, thermal stability, surface morphology, and particle size of the synthesized nanogels, respectively. Thus, we can conclude that the prepared nanogels can be used as a suitable agent for the sustained release of caffeine.

Folic acid-decorated alginate nanoparticles loaded hydrogel for the oral delivery of diferourylmethane in colorectal cancer

The disease-related suffering in colorectal cancer remains prevalent despite advancements in the field of drug delivery. Chemotherapy-related side effects and non-specificity remain a challenge in drug delivery. The great majority of hydrophobic drugs cannot be successfully delivered to the colon orally mainly due to poor solubility, low bioavailability, pH differences, and food interactions. Polymeric nanoparticles are potential drug delivery candidates but there are numerous limitations to their usefulness in colon cancer. The nanoparticles are removed from the body rapidly by p-glycoprotein efflux, inactivation, or breakdown by enzymes limiting their efficiency. Furthermore, there is a lack of selectivity in targeting cancer cells; nanoparticles may also target healthy cells, resulting in toxicity and adverse effects. The study aimed to use nanoparticles for specific targeting of the colorectal tumor cells via the oral route of administration without adverse effects. Folic acid (FA), a cancer-targeting ligand possessing a high affinity for folate receptors overexpressed in colorectal cancers was conjugated to sodium alginate- nanoparticles by NH₂-linkage. The folic-acid conjugated nanoparticles (FNPs) were delivered to the colon by a pH-sensitive hydrogel synthesized by the free radical polymerization method to provide sustained drug release. The developed system referred to as the "Hydrogel-Nano (HN) drug delivery system," was specifically capable of delivering diferourylmethane to the colon. The HN system was characterized by DLS, FTIR, XRD, TGA, DSC, and SEM. The FNPs size, polydispersity index, and zeta potential were measured. The folic acid-conjugation to nanoparticles' surface was studied by UV-visible spectroscopy using Beer-Lambert's law. In-vitro studies, including sol-gel, porosity, drug loading, entrapment efficiency, etc., revealed promising results. The swelling and release studies showed pH-dependent release of the drug in colonic pH 7.4. Cellular uptake and cytotoxicity studies performed on FR-overexpressed Hela cell lines and FR-negative A-549 cell lines showed facilitated uptake of nanoparticles by folate receptors. A threefold increase in C_max and prolongation of the mean residence time (MRT) to 14.52 +/- 0.217 h indicated sustained drug release by the HN system. The findings of the study can provide a sufficient ground that the synergistic approach of the HN system can deliver hydrophobic drugs to colorectal cancer cells via the oral route, but further in-vivo animal cancer model studies are required.

Magnetic nanoparticle embedded chitosan-based polymeric network for the hydrophobic drug delivery of paclitaxel

Safe delivery of hydrophobic drugs to the tumor site is a major problem for the scientific community. To improve the in vivo efficacy of hydrophobic drugs by avoiding solubility concerns and providing targeted delivery by nanoparticle, we have developed robust iron oxide nanoparticles coated chitosan with ([2- (methacryloyloxy) ethyl] trimethyl ammonium chloride) (METAC) [CS-IONPs-METAC-PTX] as a drug carrier for the delivery of hydrophobic drug, paclitaxel (PTX). Drug carrier was characterized using various techniques like FT-IR, XRD, FE-SEM, DLS and VSM. Maximum drug release of 93.50 ± 2.80 % from CS-IONPs-METAC-PTX occurs at pH 5.5 in 24 h. Significantly, the nanoparticles exhibited excellent therapeutic efficacy when appraised in L929 (Fibroblast) cell lines with a good cell viability profile. CS-IONPs-METAC-PTX shows excellent cytotoxic effect in MCF-7 cell lines. In 100 μg/mL concentration, CS-IONPs-METAC-PTX formulation shows 13.46 ± 0.40 % of cell viability. Selectivity index of 2.12 indicates the highly selective and safe performance of CS-IONPs-METAC-PTX. Admirable hemocompatibility of the developed polymer material demonstrating its applicability towards drug delivery. Results of the investigation substantiate that the prepared drug carrier is a potent material for the delivery of PTX.

Stimuli-Responsive and Antibacterial Cellulose-Chitosan Hydrogels Containing Polydiacetylene Nanosheets

Herein, we report a stimuli-responsive hydrogel with inhibitory activity against Escherichia coli prepared by chemical crosslinking of carboxymethyl chitosan (CMCs) and hydroxyethyl cellulose (HEC). The hydrogels were prepared by esterification of chitosan (Cs) with monochloroacetic acid to produce CMCs which were then chemically crosslinked to HEC using citric acid as the crosslinking agent. To impart a stimuli responsiveness property to the hydrogels, polydiacetylene-zinc oxide (PDA-ZnO) nanosheets were synthesized in situ during the crosslinking reaction followed by photopolymerization of the resultant composite. To achieve this, ZnO was anchored on carboxylic groups in 10,12-pentacosadiynoic acid (PCDA) layers to restrict the movement of the alkyl portion of PCDA during crosslinking CMCs and HEC hydrogels. This was followed by irradiating the composite with UV radiation to photopolymerize the PCDA to PDA within the hydrogel matrix so as to impart thermal and pH responsiveness to the hydrogel. From the results obtained, the prepared hydrogel had a pH-dependent swelling capacity as it absorbed more water in acidic media as compared to basic media. The incorporation of PDA-ZnO resulted in a thermochromic composite responsive to pH evidenced by a visible colour transition from pale purple to pale pink. Upon swelling, PDA-ZnO-CMCs-HEC hydrogels had significant inhibitory activity against E. coli attributed to the slow release of the ZnO nanoparticles as compared to CMCs-HEC hydrogels. In conclusion, the developed hydrogel was found to have stimuli-responsive properties and inhibitory activity against E. coli attributed to zinc nanoparticles.

Synthesis of Hydrogels and Their Progress in Environmental Remediation and Antimicrobial Application

As a kind of efficient adsorptive material, hydrogel has a wide application prospect within different fields, owing to its unique 3D network structures composed of polymers. In this paper, different synthetic strategies, crosslinking methods and their corresponding limitations and outstanding contributions of applications in the fields of removing environmental pollutants are reviewed to further provide a prospective view of their applications in water resources sustainability. Furthermore, the applications within the biomedical field, especially in wound dressing, are also reviewed in this paper, mainly due to their unique water retention ability, antibacterial ability, and good biocompatibility. Finally, the development direction of hydrogels in the fields of environmental remediation and biomedicine were summarized and prospected.

In-vitro and in-vivo evaluation of biocompatible polymeric microgels for pH- driven delivery of Ketorolac tromethamine

The aim of the current study was to prepare glutamic acid crosslinked poly(itaconic acid/methacrylic acid) microgels for pH-responsive delivery of ketorolac tromethamine, using aqueous free radical polymerization technique. The polymerization of polymer with monomers was carried out by a crosslinking agent N', N'-methylene bisacrylamide in the presence of initiator ammonium persulfate. The prepared microgels were characterized for structure, surface morphology, thermal stability, and crystallinity. Similarly, studies such as sol-gel analysis, drug loading, and polymer volume fraction were performed for the fabricated microgels. The pH-sensitivity of the developed microgels was investigated at three different pH values i.e., pH 1.2, 4.6, and 7.4 by swelling and in-vitro drug release studies. Maximum swelling and drug release were found at pH 7.4 as compared to pH 1.2 and 4.6, which indicated the pH-sensitive nature of the prepared microgels. The toxicity of the prepared microgels was evaluated by cell line and HET-CAM test, which demonstrated no toxic effect of the prepared microgels. In-vivo study was carried out on rabbits and high plasma concentration was reported for the drug loaded microgels as compared to drug solution and commercial product Keten. Hence, the prepared microgel system could be employed as an excellent carrier for the controlled drug delivery system.

Development and Challenges of Diclofenac-Based Novel Therapeutics: Targeting Cancer and Complex Diseases

Simple Summary

Diclofenac is a widely used drug for its anti-inflammatory and pain alleviating properties. This review summarizes the current understanding about the drug diclofenac. The potential applications of diclofenac beyond its well-known anti-inflammatory properties for other diseases such as cancer are discussed, along with existing limitations.

Abstract

Diclofenac is a highly prescribed non-steroidal anti-inflammatory drug (NSAID) that relieves inflammation, pain, fever, and aches, used at different doses depending on clinical conditions. This drug inhibits cyclooxygenase-1 and cyclooxygenase-2 enzymes, which are responsible for the generation of prostaglandin synthesis. To improve current diclofenac-based therapies, we require new molecular systematic therapeutic approaches to reduce complex multifactorial effects. However, the critical challenge that appears with diclofenac and other drugs of the same class is their side effects, such as signs of stomach injuries, kidney problems, cardiovascular issues, hepatic issues, and diarrhea. In this article, we discuss why defining diclofenac-based mechanisms, pharmacological features, and its medicinal properties are needed to direct future drug development against neurodegeneration and imperfect ageing and to improve cancer therapy. In addition, we describe various advance molecular mechanisms and fundamental aspects linked with diclofenac which can strengthen and enable the better designing of new derivatives of diclofenac to overcome critical challenges and improve their applications.

Inherent and Composite Hydrogels as Promising Materials to Limit Antimicrobial Resistance

Antibiotic resistance has increased significantly in the recent years, and has become a global problem for human health and the environment. As a result, several technologies for the controlling of health-care associated infections have been developed over the years. Thus, the most recent findings in hydrogel fabrication, particularly antimicrobial hydrogels, could offer valuable solutions for these biomedical challenges. In this review, we discuss the most promising strategies in the development of antimicrobial hydrogels and the application of hydrogels in the treatment of microbial infections. The latest advances in the development of inherently and composite antimicrobial hydrogels will be discussed, as well as hydrogels as carriers of antimicrobials, with a focus on antibiotics, metal nanoparticles, antimicrobial peptides, and biological extracts. The emergence of CRISR-Cas9 technology for removing the antimicrobial resistance has led the necessity of new and performant carriers for delivery of the CRISPR-Cas9 system. Different delivery systems, such as composite hydrogels and many types of nanoparticles, attracted a great deal of attention and will be also discussed in this review.

Fabrication of alginate based microgels for drug-sustained release: In-vitro and in-vivo evaluation

The current study was conducted to evaluate and analyze the effect of alginate, itaconic acid, and N,N'-methylene bisacrylamide in formulation of a novel alginate based microgels for sustained release of theophylline. The fabricated microgels were characterized by PXRD, SEM, FTIR, TGA and DSC respectively. FTIR revealed that alginate reacted with itaconic acid during polymerization reaction and confirmed the overlapping of itaconic acid on the backbone of alginate. TGA and DSC depicted high thermal stability of the fabricated microgels as compared to pure unreacted polymer and monomer. Likewise, dynamic swelling and percent drug release studies were carried out at different pH media i.e., pH 1.2, 4.6 and 7.4 respectively. Greater dynamic swelling and percent drug release was observed at higher pH 7.4 as compared to lower pH 4.6 and 1.2 due to the deprotonation of COOH groups of both alginate and itaconic acid respectively. The drug release mechanism from the fabricated microgels could be described by first order model. In-vivo pharmacokinetic study was performed on rabbits and exhibited sustained release in rabbits. Hence, the developed microgels indicated higher potential as the delivery system for the sustained delivery of theophylline.

Synthesis, Characterization, In-Vitro and In-Vivo Evaluation of Ketorolac Tromethamine-Loaded Hydrogels of Glutamic Acid as Controlled Release Carrier

Glutamic acid-co-poly(acrylic acid) (GAcPAAc) hydrogels were prepared by the free radical polymerization technique using glutamic acid (GA) as a polymer, acrylic acid (AAc) as a monomer, ethylene glycol dimethylacrylate (EGDMA) as a cross-linker, and ammonium persulfate (APS) as an initiator. Increase in gel fraction was observed with the increasing concentration of glutamic acid, acrylic acid, and ethylene glycol dimethylacrylate. High percent porosity was indicated by developed hydrogels with the increase in the concentration of glutamic acid and acrylic acid, while a decrease was seen with the increasing concentration of EGDMA, respectively. Maximum swelling and drug release was exhibited at high pH 7.4 compared to low pH 1.2 by the newly synthesized hydrogels. Similarly, both swelling and drug release increased with the increasing concentration of glutamic acid and acrylic acid and decreased with the increase in ethylene glycol dimethylacrylate concentration. The drug release was considered as non-Fickian transport and partially controlled by viscoelastic relaxation of hydrogel. In-vivo study revealed that the AUC_0–∞ of fabricated hydrogels significantly increased compared to the drug solution and commercial product Keten. Hence, the results indicated that the developed hydrogels could be used as a suitable carrier for controlled drug delivery.

Formulation and In-Vitro Characterization of pH-Responsive Semi-Interpenetrating Polymer Network Hydrogels for Controlled Release of Ketorolac Tromethamine

Ketorolac tromethamine is a non-steroidal anti-inflammatory drug used in the management of severe pain. The half-life of Ketorolac tromethamine is within the range of 2.5–4 h. Hence, repeated doses of Ketorolac tromethamine are needed in a day to maintain the therapeutic level. However, taking several doses of Ketorolac tromethamine in a day generates certain complications, such as acute renal failure and gastrointestinal ulceration. Therefore, a polymeric-controlled drug delivery system is needed that could prolong the release of Ketorolac tromethamine. Therefore, in the current study, pH-responsive carbopol 934/sodium polystyrene sulfonate-co-poly(acrylic acid) (CP/SpScPAA) hydrogels were developed by the free radical polymerization technique for the controlled release of Ketorolac tromethamine. Monomer acrylic acid was crosslinked with the polymers carbopol 934 and sodium polystyrene sulfonate by the cross-linker N’,N’-methylene bisacrylamide. Various studies were conducted to evaluate and assess the various parameters of the fabricated hydrogels. The compatibility of the constituents used in the preparation of hydrogels was confirmed by FTIR analysis, whereas the thermal stability of the unreacted polymers and developed hydrogels was analyzed by TGA and DSC, respectively. A smooth and porous surface was indicated by SEM. The crystallinity of carbopol 934, sodium polystyrene sulfonate, and the prepared hydrogels was evaluated by PXRD, which revealed a reduction in the crystallinity of reactants for the developed hydrogels. The pH sensitivity of the polymeric hydrogel networks was confirmed by dynamic swelling and in vitro release studies with two different pH media i.e., pH 1.2 and 7.4, respectively. Maximum swelling was exhibited at pH 7.4 compared to pH 1.2 and, likewise, a greater percent drug release was perceived at pH 7.4. Conclusively, we can demonstrate that the developed pH-sensitive hydrogel network could be employed as a suitable carrier for the controlled delivery of Ketorolac tromethamine.

Fabrication and In Vitro Evaluation of pH-Sensitive Polymeric Hydrogels as Controlled Release Carriers

The purpose of the current investigation was to develop chondroitin sulfate/carbopol-co-poly(acrylic acid) (CS/CBP-co-PAA) hydrogels for controlled delivery of diclofenac sodium (DS). Different concentrations of polymers chondroitin sulfate (CS), carbopol 934 (CBP), and monomer acrylic acid (AA) were cross-linked by ethylene glycol dimethylacrylate (EGDMA) in the presence of ammonium peroxodisulfate (APS) (initiator). The fabricated hydrogels were characterized for further experiments. Characterizations such as Scanning electron microscopy (SEM), Thermogravimetric analysis (TGA), Differential scanning calorimetry (DSC), Powder X-ray diffractometry (PXRD), and Fourier transform infrared spectroscopy (FTIR) were conducted to understand the surface morphology, thermodynamic stability, crystallinity of the drug, ingredients, and developed hydrogels. The swelling and drug release studies were conducted at two different pH mediums (pH 1.2 and 7.4), and pH-dependent swelling and drug release was shown due to the presence of functional groups of both polymers and monomers; hence, greater swelling and drug release was observed at the higher pH (pH 7.4). The percent drug release of the developed system and commercially available product cataflam was compared and high controlled release of the drug from the developed system was observed at both low and high pH. The mechanism of drug release from the hydrogels followed Korsmeyer-Peppas model. Conclusively, the current research work demonstrated that the prepared hydrogel could be considered as a suitable candidate for controlled delivery of diclofenac sodium.

Preparation and In Vitro Evaluation of Aspartic/Alginic Acid Based Semi-Interpenetrating Network Hydrogels for Controlled Release of Ibuprofen

Different combinations of polymers, aspartic acid (ASP), alginic acid (AL), and monomer acrylic acid (AA) were crosslinked in the presence of an initiator ammonium peroxodisulfate (APS) and cross-linker ethylene glycol dimethacrylate (EGDMA) to develop aspartic acid/alginic acid-co-poly(acrylic acid) (ASP/ALPAA) (semi-interpenetrating polymer network (SIPN)) hydrogels by the free radical polymerization technique for the controlled delivery of ibuprofen (IBP). Various studies such as dynamic swelling studies, drug loading, in vitro drug release and sol-gel analysis were carried out for the hydrogels. Higher swelling was observed at higher pH 7.4 as compared to lower pH 1.2, due to the presence of carboxylic groups of polymers and the monomer. Hence, pH-dependent swelling was exhibited by the developed hydrogels which led to a pH-dependent drug release and vice versa. The structural properties of the hydrogels were assessed by FTIR, PXRD, TGA, DSC, and SEM which confirmed the fabrication and stability of the developed structure. FTIR analysis revealed the reaction of both polymers with the monomer during the polymerization process and confirmed the overlapping of the monomer on the backbone of the both polymers. The disappearance of high intense crystalline peaks and the encapsulation of the drug by the hydrogel network was confirmed by PXRD. TGA and DSC showed that the developed hydrogels were thermally more stable than their basic ingredients. Similarly, the surface morphology of the hydrogels was analyzed by SEM and showed a smooth surface with few pores. Conclusively, ASP/ALPAA hydrogels have the potential to deliver IBP for a long period of time in a controlled way.