Current Advances in Stimuli-Responsive Hydrogels as Smart Drug Delivery Carriers

Advances in Brain Stimulation, Nanomedicine and the Use of Magnetoelectric Nanoparticles: Dopaminergic Alterations and Their Role in Neurodegeneration and Drug Addiction

Recent advancements in brain stimulation and nanomedicine have ushered in a new era of therapeutic interventions for psychiatric and neurodegenerative disorders. This review explores the cutting-edge innovations in brain stimulation techniques, including their applications in alleviating symptoms of main neurodegenerative disorders and addiction. Deep Brain Stimulation (DBS) is an FDA-approved treatment for specific neurodegenerative disorders, including Parkinson's Disease (PD), and is currently under evaluation for other conditions, such as Alzheimer's Disease. This technique has facilitated significant advancements in understanding brain electrical circuitry by enabling targeted brain stimulation and providing insights into neural network function and dysfunction. In reviewing DBS studies, this review places particular emphasis on the underlying main neurotransmitter modifications and their specific brain area location, particularly focusing on the dopaminergic system, which plays a critical role in these conditions. Furthermore, this review delves into the groundbreaking developments in nanomedicine, highlighting how nanotechnology can be utilized to target aberrant signaling in neurodegenerative diseases, with a specific focus on the dopaminergic system. The discussion extends to emerging technologies such as magnetoelectric nanoparticles (MENPs), which represent a novel intersection between nanoformulation and brain stimulation approaches. These innovative technologies offer promising avenues for enhancing the precision and effectiveness of treatments by enabling the non-invasive, targeted delivery of therapeutic agents as well as on-site, on-demand stimulation. By integrating insights from recent research and technological advances, this review aims to provide a comprehensive understanding of how brain stimulation and nanomedicine can be synergistically applied to address complex neuropsychiatric and neurodegenerative disorders, paving the way for future therapeutic strategies.

Preparation and Characterization of Chitosan/Hydroxypropyl Methylcellulose Temperature-Sensitive Hydrogel Containing Inorganic Salts for Forest Fire Suppression

Effective forest fire suppression remains a critical challenge, necessitating innovative solutions. Temperature-sensitive hydrogels represent a promising avenue in this endeavor. Traditional firefighting methods often struggle to address forest fires efficiently while mitigating ecological harm and optimizing resource utilization. In this study, a novel intelligent temperature-sensitive hydrogel was prepared specially for forest fire extinguishment. Utilizing a one-pot synthesis approach, this material demonstrates exceptional fluidity at ambient temperatures, facilitating convenient application and transport. Upon exposure to elevated temperatures, it undergoes a phase transition to form a solid, barrier-like structure essential for containing forest fires. The incorporation of environmentally friendly phosphorus salts into the chitosan/hydroxypropyl methylcellulose gel system enhances the formation of temperature-sensitive hydrogels, thereby enhancing their structural integrity and firefighting efficacy. Morphological and thermal stability analyses elucidate the outstanding performance, with the hydrogel forming a dense carbonized layer that acts as a robust barrier against the spread of forest fires. Additionally, comprehensive evaluations employing rheological tests, cone calorimeter tests, a swelling test, and infrared thermography reveal the multifaceted roles of temperature-sensitive hydrogels in forest fire prevention and suppression strategies.

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.

Injectable Hydrogels for Nervous Tissue Repair-A Brief Review

The repair of nervous tissue is a critical research field in tissue engineering because of the degenerative process in the injured nervous system. In this review, we summarize the progress of injectable hydrogels using in vitro and in vivo studies for the regeneration and repair of nervous tissue. Traditional treatments have not been favorable for patients, as they are invasive and inefficient; therefore, injectable hydrogels are promising for the treatment of damaged tissue. This review will contribute to a better understanding of injectable hydrogels as potential scaffolds and drug delivery system for neural tissue engineering applications.

Preparation of PLGA Microspheres Using the Non-Toxic Glycofurol as Polymer Solvent by a Modified Phase Inversion Methodology

Poly(D,L-lactide-co-glycolide is a biodegradable copolymer that can release pharmaceuticals. These pharmaceuticals can provide local therapy and also avert the clinical issues that occur when a drug must be given continuously and/or automatically. However, the drawbacks of using poly(D,L-lactide-co-glycolide include the kinetics and duration of time of poly(D,L-lactide-co-glycolide drug release, the denaturing of the drug loaded drug, and the potential clinical side effects. These drawbacks are mainly caused by the volatile organic solvents needed to prepare poly(D,L-lactide-co-glycolide spheres. Using the non-toxic solvent glycofurol solvent instead of volatile organic solvents to construct poly(D,L-lactide-co-glycolide microspheres may deter the issues of using volatile organic solvents. Up to now, preparation of such glycofurol spheres has previously met with limited success. We constructed dexamethasone laden poly(D,L-lactide-co-glycolide microspheres utilizing glycofurol as the solvent within a modified phase inversion methodology. These prepared microspheres have a higher drug load and a lower rate of water diffusion. This prolongs drug release compared to dichloromethane constructed spheres. The glycofurol-generated spheres are also not toxic to target cells as is the case for dichloromethane-constructed spheres. Further, glycofurol-constructed spheres do not denature the dexamethasone molecule and have kinetics of drug release that are more clinically advantageous, including a lower drug burst and a prolonged drug release.