Development and Optimization of Tamarind Gum-β-Cyclodextrin-g-Poly(Methacrylate) pH-Responsive Hydrogels for Sustained Delivery of Acyclovir

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.

Fabrication and characterization of tamarind seed gum based novel hydrogel for the targeted delivery of omeprazole magnesium

The tamarind seed gum based novel hydrogel was fabricated by varying concentration of polymer, monomer and crosslinker for the targeted delivery of omeprazole magnesium at stomach pH of 1.5. The free radical graft copolymerization of 2-acrylamido-2-methyl propane sulfonic acid with tamarind seed gum backbone resulted in hydrogel. The formation of sulfonic acid pendant groups in hydrogel was observed by the existence of an infrared absorption band at 1152 cm-1 for SO group. The conversion to semicrystalline nature on incorporation of drug evidenced by powder X-ray diffraction studies with peaks at 2θ = 20.4° 31.5° and 52.2°. The scanning electron microscopy images showed bigger voids which narrowed down for drug loaded matrix, supported by the presence of a peak for magnesium in the energy dispersive X-ray spectroscopy. The greatest swelling was observed at pH 7 with second-order rate constant 1.5371 (g/g)/min and drug release was found to be 97.85 ± 1 % over 1200 min at pH 1.5. The drug release transport was found combination of diffusion and erosion of polymer chain to be super case II diffusion and Hill equation model was good fit. The hydrogel drug conjugate found to be non-toxic at tested concentrations (17 mg/50 mg) on in-vivo testing in Drosophila model.

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.

Fabrication of Stimuli-Responsive Quince/Mucin Co-Poly (Methacrylate) Hydrogel Matrices for the Controlled Delivery of Acyclovir Sodium: Design, Characterization and Toxicity Evaluation

Free-radical polymerization technique was adopted to fabricate a stimuli-responsive intelligent quince/mucin co-poly (methacrylate) hydrogel for the controlled delivery of acyclovir sodium. The developed hydrogel matrices were appraised using different parameters, such as drug loading (%), swelling kinetics, pH- and electrolyte-responsive swelling, and sol-gel fraction. Drug-excipient compatibility study, scanning electron microscopy, thermal analysis, powder X-ray diffraction (PXRD) analysis, in vitro drug release studies, drug release kinetics and acute oral toxicity studies were conducted. The results of drug loading revealed an acyclovir sodium loading of 63-75% in different formulations. The hydrogel discs exhibited pH-responsive swelling behavior, showing maximum swelling in a phosphate buffer with a pH of 7.4, but negligible swelling was obvious in an acidic buffer with a pH of 1.2. The swelling kinetics of the developed hydrogel discs exhibited second-order kinetics. Moreover, the hydrogel discs responded to the concentration of electrolytes (CaCl₂ and NaCl). The results of the FTIR confirm the formation of the hydrogel via free-radical polymerization. However, the major peaks of acyclovir remain intact, proving drug-excipient compatibility. The results of the SEM analysis reveal the porous, rough surface of the hydrogel discs with multiple cracks and pores over the surface. The results of the PXRD disclose the amorphous nature of the fabricated hydrogel. The dissolution studies showed a minor amount of acyclovir sodium released in an acidic environment, while an extended release up to 36 h in the phosphate buffer was observed. The drug release followed Hixen-Crowell's kinetics with Fickian diffusion mechanism. The toxicity studies demonstrated the non-toxic nature of the polymeric carrier system. Therefore, these results signify the quince/mucin co-poly (methacrylate) hydrogel as a smart material with the potential to deliver acyclovir into the intestine for an extended period of time.