Search Results (394)

Inflammatory arthritis (IA) is a chronic condition marked by joint dysfunction and pain, posing significant challenges for effective drug delivery. This study separated Perilla frutescens leaf-derived exosome-like nanovesicles (PFE) to effectively penetrate the stratum corneum barrier. These nanovesicles and indomethacin (IND) were subsequently developed into a nanogel designed for topical drug delivery systems (PFE-IND-GEL). PFE exhibited a typical vesicular structure with a mean diameter of 98.4 ± 1.3 nm. The hydrodynamic size and zeta potential of PFE-IND-GEL were 129.6 ± 5.9 nm and −17.4 ± 1.9 mV, respectively. Mechanistic investigations in HaCaT keratinocytes showed that PFE significantly downregulated tight junction proteins (ZO-1 and Occludin, p < 0.01) via modulation of the IL-17 signaling pathway, as evidenced by transcriptomic analysis. In a sodium urea crystal-induced rat IA model, the topical application of PFE-IND-GEL significantly reduced joint swelling (p < 0.05) and serum levels of inflammatory cytokines (IL-6, IL-1α, TNF-α) compared to control groups. Histopathological analysis confirmed the marked attenuation of synovial inflammation and cartilage preservation in treated animals. These findings underscore the dual role of PFE as both a topical permeation enhancer and an anti-inflammatory agent, presenting a promising strategy for managing IA. Full article

Poly(N-vinyl-2-pyrrolidone), or PVP, nanogels loaded with gadolinium nitrate (Gd(NO₃)₃·6H₂O) were synthesized by ionizing irradiation, aiming for potential applications in magnetic resonance imaging (MRI). A comprehensive characterization of PVP and Gd aqueous solutions with different VP-monomer-to-Gd ratios was conducted before and after irradiation. The results indicate a complexation between PVP and Gd ions before irradiation. The size of the nanogels exhibited a strong dependence on several factors, including PVP molecular weight, concentration, temperature, and the precise timing of Gd introduction relative to the irradiation process. A quantification study was conducted to investigate the impact of molecular weight, the VP/Gd ratio, and Gd addition before or after the irradiation process on the concentration of free Gd ions. These findings offer valuable insights into optimizing the synthesis of Gd-loaded PVP nanogels for potential applications, highlighting the critical factors that influence their size and stability. Full article

Curcumin is widely recognized for its various pharmacological properties, including antioxidant, anti-inflammatory, and anti-tumor activities. Nevertheless, the development of curcumin as a therapeutic agent is impeded by its limited oral bioavailability, which stems from its chemical instability, poor aqueous solubility, and rapid degradation. This study aimed to develop granule formulations incorporating poly(N-isopropylacrylamide)-grafted hyaluronic acid or HA-g-pNIPAM to enhance dissolution and protect curcumin from degradation. Three formulations were developed: F10 (HA-g-pNIPAM physically mixed with curcumin), F10 Encap (curcumin encapsulated within HA-g-pNIPAM), and F11 (curcumin granules without HA-g-pNIPAM). The stability results showed that F10 Encap effectively maintained curcumin content throughout the study period, retaining approximately 94% of its initial concentration by day 30, compared to 70% from F11 (p < 0.05) at 30 °C and 75% relative humidity. All dried curcumin granules exhibited excellent flowability, as determined by the angle of repose measurements. All three formulations exhibited a consistent particle size distribution across replicates, with a peak in the 150–180 μm size range. The sustained release observed for F10 Encap and F10 after the initial burst suggested that the HA-g-pNIPAM provided a controlled release mechanism, ensuring continuous curcumin dissolution over 240 min in gastric and intestinal conditions. These findings suggested that HA-g-pNIPAM improved dissolution and stability of curcumin. Full article

This study addresses the unclear mechanisms by which preferential flow channels (PFCs), formed during long-term waterflooding, affect nano-gel microsphere (NGM) flooding efficiency, utilizing CMG reservoir numerical simulation software. A dynamic evolution model of PFCs was established by coupling CROCKTAB (stress–porosity hysteresis) and CROCKTABW (water saturation-driven permeability evolution), and the deep flooding mechanism of NGMs (based on their gel properties such as swelling, elastic deformation, and adsorption, and characterized by a “plugging-migration-replugging” process) was integrated. The results demonstrate that neglecting PFCs overestimates recovery by 8.7%, while NGMs reduce permeability by 33% (from 12 to 8 mD) in high-conductivity zones via “bridge-plug-filter cake” structures, diverting flow to low-permeability layers (+33% permeability, from 4.5 to 6 mD). Field application in a Chang 6 tight reservoir (permeability variation coefficient 0.82) confirms a >10-year effective period with 0.84% incremental recovery (from 7.31% to 8.15%) and favorable economics (ROI ≈ 10:1), providing a theoretical and engineering framework for gel-based conformance control in analogous reservoirs. Full article

Central nervous system diseases are highly complex in terms of etiology and pathogenesis, making their treatment and interventions for them a major focus and challenge in neuroscience research. Anthocyanins, natural water-soluble pigments widely present in plants, belong to the class of flavonoid compounds. As natural antioxidants, anthocyanins have attracted extensive attention due to their significant functions in scavenging free radicals, antioxidation, anti-inflammation, and anti-apoptosis. The application of anthocyanins in the field of central nervous system injury, particularly in neurodegenerative diseases, neurotoxicity induced by chemical drugs, stress-related nerve damage, and cerebrovascular diseases, has achieved remarkable research outcomes. However, anthocyanins often exhibit low chemical stability, a short half-life, and relatively low bioavailability, which limit their clinical application. Recent studies have found that the stability and bioavailability of anthocyanins can be significantly improved through nanoencapsulation, acylation, and copigmentation, as well as the preparation of nanogels, nanoemulsions, and liposomes. These advancements offer the potential for the development of anthocyanins as a new type of neuroprotective agent. Future research will focus on the innovative design of nano-delivery systems and structural modification based on artificial intelligence. Such research is expected to break through the bottleneck of anthocyanin application and enable it to become a core component of next-generation intelligent neuroprotective agents. Full article

Background: Chitosan (CS) crosslinked with genipin (GNP) provides a mild, non-toxic route to generate nanogels (NGs) with enhanced integrity and colloidal stability. Objectives: To develop and characterise CS-GNP NG as a novel platform for targeted cellular delivery, optimising design through physicochemical characterisation and biocompatibility evaluation. Methods: NGs were synthesised under optimised conditions by adjusting the pH of the CS solution, followed by high-intensity ultrasound (HIUS) to achieve disaggregation. Physicochemical characterisation was carried out using UV-Vis spectroscopy, FTIR, dynamic light scattering (DLS), and scanning electron microscopy (SEM). Rheological studies and SAXS analysis assessed structural properties. Biocompatibility was evaluated via MTT assay, and internalisation was monitored by fluorescence microscopy on mammalian cell lines. Results: NG formation was highly pH-dependent, with optimal configuration at pH 4.5, yielding stable, uniformly sized particles (~200 nm, ζ-potential +29 mV). Kinetic modelling showed a sigmoidal formation pattern, suggesting nucleation, growth, and stabilisation. FTIR confirmed covalent bonding between CS and GNP via primary amide bonds and Schiff bases. Rheology indicated pseudoplastic behaviour, and SAXS revealed a compact network formation. Biocompatibility assays confirmed non-cytotoxicity below 100 µg/mL and efficient cellular uptake. Conclusions: This study presents a rapid, reproducible protocol for generating colloidally stable, biocompatible NGs suitable for drug delivery. Full article

Hydrogel particles, renowned for their high water content and biocompatibility in drug delivery and tissue engineering, typically rely on complex, costly microfluidic systems to reach sub 5 µm dimensions. We present a vortex-based inverse-emulsion polymerization strategy in which UV crosslinking of polyethylene glycol diacrylate (PEGDA) dispersed in n-hexadecane and squalene yields tunable micro- and nanogels while delineating the parameters that govern particle size and uniformity. Systematic variation in surfactant concentration, vessel volume, continuous phase viscosity, vortex speed and duration, oil-to-polymer ratio, polymer molecular weight, and pulsed vortexing revealed that increases in surfactant level, vortex intensity/duration, vessel volume, and oil-to-polymer ratio each reduced mean diameter and PDI, whereas higher polymer molecular weight and continuous phase viscosity broadened the size distribution. We further investigated how these same parameters can be tuned to shift particle populations between nano- and microscale regimes. Under optimized conditions, microhydrogels achieved a coefficient of variation of 0.26 and a PDI of 0.07, with excellent reproducibility, and nanogels measured 161 nm (PDI = 0.05). This rapid, cost-effective method enables precise and scalable control over hydrogel dimensions using only standard laboratory equipment, without specialized training. Full article

To enhance the antibacterial activity of cefquinome (CEF) against Escherichia coli, a Carboxymethylcellulose sodium (CMCNa)/D-Mannosamine hydrochloride (DMH)-based nanogels delivery system capable of protecting CEF from gastric acid degradation while enabling intestinal sustained release and targeted antibacterial enhancement was developed. Systematic research was conducted on the best formulation, physicochemical characteristics, stability, gastrointestinal fluid-responsiveness, and antibacterial activity of the optimal formulation. The results showed that the optimized CEF nanogels demonstrated an enhanced loading capacity (13.0% ± 1.7%) and encapsulation efficiency (52.2% ± 1.0%). CEF nanogels appeared as uniform transparent spheres with a smooth surface under transmission electron microscopy and exhibited a three-dimensional porous network via scanning electron microscopy. More importantly, stability studies revealed that the CEF nanogels hold satisfactory stability. In addition, the formed CEF nanogels could effectively avoid the destruction of CEF by gastric acid in simulated gastric juice. In addition, they had the effect of slow and targeted release in the simulated intestinal tract. Compared to the free CEF, CEF nanogels have stronger antibacterial activity against Escherichia coli. In short, the prepared CEF nanogels had stronger antibacterial activity than CEF through sustained and targeted release. Full article

Background/Objectives: Photothermal therapy (PTT) is an emerging minimally invasive strategy in biomedicine that converts near-infrared (NIR) light into localized heat for the targeted inactivation of pathogens and tumor cells. Methods and Results: In this study, we report the synthesis and characterization of thermoresponsive nanogels composed of poly (N-isopropylacrylamide-co-N-isopropylmethylacrylamide) (PNIPAM-co-PNIPMAM) semi-interpenetrated with polypyrrole (PPy), yielding monodisperse particles of 377 nm diameter. Spectroscopic analyses—including ¹H-NMR, FTIR, and UV-Vis—confirmed successful copolymer formation and PPy incorporation, while TEM images revealed uniform spherical morphology. Differential scanning calorimetry established a volumetric phase transition temperature of 38.4 °C, and photothermal assays demonstrated a ΔT ≈ 10 °C upon 10 min of 850 nm NIR irradiation. In vitro antimicrobial activity tests against Pseudomonas aeruginosa (ATCC 15692) showed a dose-time-dependent reduction in bacterial viability, with up to 4 log CFU/mL. Additionally, gentamicin-loaded nanogels achieved 38.7% encapsulation efficiency and exhibited stimulus-responsive drug release exceeding 75% under NIR irradiation. Conclusions: Combined photothermal and antibiotic therapy yielded augmented bacterial killing, underscoring the potential of PPy-interpenetrated nanogels as smart, dual-mode antimicrobials. Full article

Global concerns about environmental pollution, poor waste management, and the rise in antimicrobial resistance due to uncontrolled antibiotic use have driven researchers to seek alternative, multifaceted solutions. Plants, animals, microorganisms, and their processing wastes serve as valuable sources of natural biopolymers and bioactive compounds. Through nanotechnology, these can be assembled into formulations with enhanced antimicrobial properties, high safety, and low toxicity. This review explores polysaccharides, including chitosan, alginate, starch, pectin, cellulose, hemicellulose, gums, carrageenan, dextran, pullulan, and hyaluronic acid, used in nanotechnology, highlighting their advantages and limitations as nanocarriers. Addressing the global urgency for alternative antimicrobials, we examined natural compounds derived from plants, microorganisms, and animals, such as phytochemicals, bacteriocins, animal antimicrobial peptides, and proteins. Focusing on their protection and retained activity, this review discusses polysaccharide-based nanoformulations with natural antimicrobials, including nanoparticles, nanoemulsions, nanocapsules, nanoplexes, and nanogels. Special emphasis is placed on strategies and formulations for the encapsulation, entrapment, and conjugation of natural compounds using polysaccharides as protective carriers and delivery systems, including a brief discussion on their future applications, prospects, and challenges in scaling up. Full article

Neurosteroids pregnenolone, progesterone, allopregnanolone, and dehydroepiandrosterone have been actively studied in the last years as candidates for the treatment of neurodegenerative diseases and postinjury rehabilitation. The neuroprotective mechanisms of these neurosteroids have been shown in clinical studies of depression, epilepsy, status epilepticus, traumatic brain injury, fragile X syndrome, and chemical neurotoxicity. However, only the allopregnanolone analogs brexanolone and zuranolone have been recently approved by the FDA for the treatment of depression. The aim of this review was to evaluate whether the endogenous neurosteroids can be used in clinical practice as neuroprotectors. Neurosteroids are multitarget compounds with strong anti-inflammatory, immunomodulatory, and cytoprotective action; they stimulate the synthesis and release of BDNF and increase remyelination and regeneration. In addition to nuclear and membrane steroid hormone receptors, such as PR, mPR, PGRMC1,2, ER, AR, CAR, and PXR, they can bind to GABAA receptors, NMDA receptors, Sigma-1 and -2 receptors (σ1-R/σ2-R). Among these, mPRs, PGRMC1,2, sigma receptors, and mitochondrial proteins attract comprehensive attention because of strong binding with the P4 and DHEA, but subsequent signaling is poorly studied. Other plasma membrane and mitochondrial proteins are involved in the rapid nongenomic neuroprotective action of neurosteroids. P-glycoprotein, BCL-2 proteins, and the components of the mitochondrial permeability transition pore (mPTP) play a significant role in the defense against the injuries of the brain and the peripheral nervous system. The role of these proteins in the molecular mechanisms of action in neuroprotection and neuroinflammation has not yet been clearly established. The aspects of their participation in these pathological processes are discussed. New formulations, such as lipophilic emulsions, nanogels, and microneedle array patches, are attractive strategies to overcome the low bioavailability of these neurosteroids for the amelioration and treatment of various nervous disorders. Full article

Chronic wounds, such as diabetic ulcers and pressure injuries, remain a major global health burden, affecting over 40 million people worldwide and imposing significant socioeconomic strain. Hydrogel-based wound dressings have gained clinical attention for their ability to maintain moisture, mimic the extracellular matrix, and support tissue regeneration. However, traditional hydrogels often lack the mechanical robustness, antimicrobial efficacy, and dynamic responsiveness needed to treat complex wound environments effectively. To address these limitations, nanohybrid hydrogels, composite systems that integrate functional nanomaterials into hydrogel matrices, have emerged as intelligent platforms for advanced wound care. These systems enable multifunctional therapeutic action, including antibacterial activity, antioxidant regulation, angiogenesis promotion, immune modulation, and stimuli-responsive drug delivery. This review synthesizes recent advances in nanohybrid hydrogel design, beginning with an overview of traditional polymeric systems and their constraints. We categorize functional mechanisms according to biological targets and classify nanohybrid architectures by material type, including metal-based nanoparticles, nanozymes, carbon-based nanomaterials, polymeric nanogels, and metal–organic frameworks. Representative studies are summarized in a comparative table, and challenges related to biosafety, clinical translation, and design optimization are discussed. Nanohybrid hydrogels represent a rapidly evolving frontier in wound care, offering bioresponsive, multifunctional platforms with the potential to transform chronic wound management. Full article

Chronic wounds, including diabetic foot ulcers and pressure sores, are becoming more prevalent due to aging populations and increased metabolic problems. These wounds often persist due to impaired healing, chronic inflammation, oxidative stress, and infections caused by multidrug-resistant pathogens, making conventional treatments—including antibiotics and antiseptics—largely inadequate. This creates an urgent need for advanced, biologically responsive therapies that can both combat infection and promote tissue regeneration. Probiotics have surfaced as a viable option owing to their capacity to regulate immune responses, impede pathogenic biofilms, and generate antibacterial and antioxidant metabolites. However, their clinical application is limited by poor viability, sensitivity to environmental conditions, and short retention at wound sites. Nanotechnology-based delivery systems address these limitations by protecting probiotics from degradation, enhancing site-specific delivery, and enabling controlled, stimuli-responsive release. Encapsulation techniques using materials like chitosan, PLGA, liposomes, nanogels, nanofibers, and microneedles have shown significant success in improving wound healing outcomes in preclinical and clinical models. This review summarizes the current landscape of chronic wound challenges and presents recent advances in probiotic-loaded nanotechnologies. It explores various nano-delivery systems, their mechanisms of action, biological effects, and therapeutic outcomes, highlighting the synergy between probiotics and nanocarriers as a novel, multifaceted strategy for managing chronic wounds. Full article

Psoriasis is a chronic inflammatory skin disease characterised by increased oxidative stress, the overproliferation of keratinocytes, the accumulation of inflammatory mediators, and skin barrier damage. Although a number of therapeutic options are available, finding long-term treatments that are well-tolerated and patient-friendly treatments remains a challenge. Tapinarof is a new type of aryl hydrocarbon receptor (AhR) modulator that has recently attracted attention as a promising non-steroidal alternative. However, its application may be limited by its poor water solubility and low degree of skin penetration. Nanotechnology-based drug carriers, specially nanogels, offer new opportunities to overcome these limitations by combining the advantages of targeted drug delivery and enhanced skin penetration. Furthermore, nanogel formulations can improve skin hydration and support the restoration of skin barrier function, which are important in the treatment of psoriasis. This review focuses on current and emerging therapeutic approaches, with particular emphasis on the potential of incorporating tapinarof into nanogel formulations as a novel alternative to topical psoriasis treatment. Full article

The hyperglycemic microenvironment in diabetic wounds predisposes them to bacterial infections, sustains chronic inflammation, and hinders therapeutic efficacy. In this study, antibiotic-loaded fast-crosslinked hybrid nanogel wound dressings (florfenicol nanogels) based on Schiff’s base bond were obtained through N, O-carboxymethyl chitosan (N, O-CMCS) and oxidized hyaluronic acid (OHA). The successfully prepared florfenicol N, O-CMCS/OHA nanogels exhibited obvious pH- and HAase-responsiveness release, which allowed it to quickly release florfenicol at infected wounds to exert on-demand antibacterial activity, as well as accelerate diabetic bacterial-infected wound healing. The nanogel dressings showed excellent antibacterial activity by destroying the bacterial cell membrane and wall. More specifically, the glucose oxidase in the dressings can catalyze the breakdown of high-concentration glucose, generating abundant ROS that directly cause cellular damage. According to the results of wound healing, the dressings showed satisfactory anti-inflammatory and therapeutic effects for the full-thickness mouse skin defect wounds. The nanogel dressings are anticipated to be excellent wound dressings to synergistically overcome the theraputic difficulty of diabetic bacterial wounds. Full article