Search Results (355)

Developing a rapidly gel-forming, in situ sprayable hydrogel with wound dressing functionality is essential for enhancing the wound healing process. In this study, a novel sprayable hydrogel-based wound dressing was developed by combining thermo- and pH- responsive polymers including Pluronic F127 (PF127) and N-succinyl chitosan (NSC). NSC was prepared by modifying chitosan with succinic anhydride, as confirmed by Fourier-transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The NSC synthesized using a succinic anhydride-to-chitosan molar ratio of 5:1 exhibited the highest degree of substitution, resulting in a water-soluble polymer effective over a broad pH range. The formulation process of the PF127:NSC sprayable hydrogel was optimized and evaluated based on its sol–gel phase transition behavior, clarity, gelation time, liquid and moisture management, stability, and cytotoxicity. These properties can be suitably tailored by adjusting the concentrations of PF127 and NSC. Moreover, the antioxidant capacity of the hydrogels was enhanced by incorporating Azadirachta indica (neem) extract, a bioactive compound, into the optimized sprayable hydrogel. Both neem release and antioxidant activity increased in a dose-dependent manner. Overall, the developed sprayable hydrogel exhibited favorable sprayability, appropriate gelation properties, controlled drug release, and antioxidant activity, underscoring its promising translational potential as a wound dressing. Full article

In recent years, industrial wastewater discharge containing heavy metals has increased significantly and has adversely affected both human health and the aquatic ecosystem. The increasing demand for metals in industry has prompted researchers to focus on developing effective and economical methods for removal of these metals. In this study, the removal of Ni(II) from wastewater using the Graphene oxide@Fe₃O₄@Pluronic-F68 (GO@Fe₃O₄@Pluronic-F68) nano composite as an adsorbent was investigated. The nanocomposite was characterised using a series of analytical methods, including Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) analysis. The effects of contact time, pH, adsorbent amount, and temperature parameters on adsorption were investigated. Various adsorption isotherm models were applied to interpret the equilibrium data in aqueous solutions; the compatibility of the Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich models with experimental data was examined. For a kinetic model consistent with experimental data, pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion models were examined. The maximum adsorption capacity was calculated as 151.5 mg·g⁻¹ in the Langmuir isotherm model. The most suitable isotherm and kinetic models were the Freundlich and pseudo-second-order kinetic models, respectively. These results demonstrate the potential of the GO@Fe₃O₄@Pluronic-F68 nanocomposite as an adsorbent offering a sustainable solution for Ni(II) removal. Full article

Leishmaniasis is an infectious disease common in tropical and subtropical regions worldwide. This study aimed to develop a topical meglumine antimoniate gel (MA-gel) for the treatment of cutaneous leishmaniasis. The MA-gel was characterized in terms of morphology, pH, swelling, porosity, rheology, and thermal properties by differential scanning calorimetry (DSC). Biopharmaceutical evaluation included in vitro drug release and ex vivo skin permeation. Safety was evaluated through biomechanical skin property measurements and cytotoxicity in HaCaT and RAW 267 cells. Leishmanicidal activity was tested against promastigotes and amastigotes of Leishmania infantum, and in silico studies were conducted to explore possible mechanisms of action. The composition of the MA-gel included 30% MA, 20% Pluronic^® F127 (P407), and 50% water. Scanning electron microscopy revealed a sponge-like and porous internal structure of the MA-gel. This formula exhibited a pH of 5.45, swelling at approximately 12 min, and a porosity of 85.07%. The DSC showed that there was no incompatibility between MA and P407. Drug release followed a first-order kinetic profile, with 22.11 µg/g/cm² of the drug retained in the skin and no permeation into the receptor compartment. The MA-gel showed no microbial growth, no cytotoxicity in keratinocytes, and no skin damage. The IC₅₀ for promastigotes and amastigotes of L. infantum were 3.56 and 23.11 µg/mL, respectively. In silico studies suggested that MA could act on three potential therapeutic targets according to its binding mode. The MA-gel demonstrated promising physicochemical, safety, and antiparasitic properties, supporting its potential as a topical treatment for cutaneous leishmaniasis. Full article

Surfactants are widely utilized in agriculture as emulsifying, dispersing, anti-foaming, and wetting agents. In these adjuvant roles, the inherent biological activity of the surfactant is secondary to the active ingredients. Here, the hydrophilic non-ionic surface-active tri-block copolymer Pluronic^® F68 is investigated for direct biological activity in wheat. F68 binds to and inserts into lipid membranes, which may benefit crops under abiotic stress. F68’s interactions with Triticum aestivum (var Juniper) seedlings and a seed-borne Bacillus spp. endophyte are presented. At concentrations below 10 g/L, F68-primed wheat seeds exhibited unchanged emergence. Root-applied fluorescein-F68 (fF68) was internalized in root epidermal cells and concentrated in highly mobile endosomes. The potential benefit of F68 in droughted wheat was examined and contrasted with wheat treated with the osmolyte, glycine betaine (GB). Photosystem II activity of droughted plants dropped significantly below non-droughted controls, and no clear benefit of F68 (or GB) during drought or rehydration was observed. However, F68-treated wheat exhibited increased transpiration values (for watered plants only) and enhanced shoot dry mass (for watered and droughted plants), not observed for GB-treated or untreated plants. The release of seed-borne bacterial endophytes into the spermosphere of germinating seeds was not affected by F68 (for F68-primed seeds as well as F68 applied to roots), and the planktonic growth of a purified Bacillus spp. seed endophyte was not reduced by F68 applied below the critical micelle concentration. These studies demonstrated that F68 entered wheat root cells, concentrated in endosomes involved in transport, significantly promoted shoot growth, and showed no adverse effects to plant-associated bacteria. Full article

PVDF/TiO₂ composite membranes show some potential to be used for water treatment as they combine the advantages of polymers and ceramics. However, conventional PVDF-based composite membranes are always fabricated by using conventional toxic solvents. Herein, PolarClean was used as a green solvent to fabricate PVDF/TiO₂ composite membranes via the phase inversion method. In this process, Pluronic F127 was used as a dispersion agent to distribute TiO₂ particles in the PVDF matrix and to serve as a pore former on the membrane surface. TiO₂ particles were well distributed on the membrane surface and bulk. TiO₂ particles in the PVDF matrix enhanced the mechanical strength and hydrophilic characteristics of the resulting composite membrane, facilitating water transport through the composite membranes and enhancing their water permeability. Membrane microstructures and mechanical strength of the composite membranes were finely tuned by varying the PVDF concentration, TiO₂ concentration, and coagulation bath temperature. It was demonstrated that the resulting green PVDF/TiO₂ composite membrane showed a high water permeance compared with those using conventional toxic solvents in terms of its small pore size. In addition, the particle rejection of green PVDF/TiO₂ membrane showed a 99.9% rejection rate in all the filtration process, while those using NMP showed 91.1% after 30 min of filtration. The water flux was similar at 121 and 130 Lm⁻²h⁻¹ for green and conventional solvents, respectively. This work provides important information for the future application of sustainable membranes. Full article

The interest in macromolecular alkoxysilyl-functionalized hybrids (self-assembling or nanostructured), which could be used as precursors in biomimetic silica precipitation and for the synthesis of hollow spherical silica particles, is growing. Nevertheless, reports on all-organosilicon systems for bioinspired silica precipitation are scarce. Therefore, a new kind of polyalkoxysilane macromonomer–linear polysilsesquioxane (LPSQ) of ladder-like backbone, functionalized in side chains with trimethoxysilyl groups (LPSQ-R-Si(OMe)₃), was designed following this approach. It was obtained by photoinitiated thiol-ene addition of 3-mercaptopropyltrimethoxysilane to the vinyl-functionalized polysilsesquioxane precursor, carried out in situ in tetraethoxysilane (TEOS). The mixture of LPSQ-R-Si(OMe)₃ and TEOS (co-monomers) was used in a sol–gel process conducted under acidic conditions (0.5 M HCl/NaCl) in the presence of Pluronic^® F-127 triblock copolymer as a template. LPSQ-R-Si(OMe)₃ played a key role for the formation of microparticles of a spherical shape that were formed under the applied conditions, while their size (as low as 3–4 µm) was controlled by the stirring rate. The hybrid materials were hydrophobic and showed good thermal and oxidative stability. Introduction of zinc acetate (Zn(OAc)₂) as an additive in the sol–gel process influenced the pH of the reaction medium, which resulted in structural reinforcement of the hybrid microparticles owing to more effective condensation of silanol groups and a relative increase of the content of SiO₂. The proposed method shows directions in designing the properties of hybrid materials and can be translated to other silicon–organic polymers and oligomers that could be used to produce hollow silica particles. The established role of various factors (macromonomer structure, pH, and stirring rate) allows for the modulation of particle morphology. Full article

Background/Objectives: Candidiasis, primarily caused by Candida albicans, and sporotrichosis, mainly caused by Sporothrix schenckii, are skin fungal infections that pose serious threats to global health. The Candida auris is a great concern in immunocompromised individuals, and while Sporothrix brasiliensis cause sporotrichosis, an infection commonly found in cats, this disease can be transmitted to humans through scratches or bites. Existing treatments for these fungal infections often cause problems related to resistance and significant side effects. Consequently, development of alternative therapeutic approaches such as nanotechnology-based topical lipid-based formulations is interesting. Thus, the objectives of this study were to prepare clove oil (CO)-in-water nanoemulsions (NEs) containing amphotericin B (AmB) and characterize them with respect to stability, release profile, and in vitro cytotoxic activity against Candida and Sporothrix strains. As a future alternative for the treatment of fungal skin diseases. Methods: Chemical analysis of clove oil was obtained by GC-MS. The NEs were produced using an ultrasound (sonicator) method with varying proportions of CO, Pluronic^® F-127, and AmB. The NEs were characterized by droplet size, morphology, stability and in vitro release profile. The antifungal and cytotoxic activity against C. albicans, C. auris, S. schenckii, and S. brasiliensis were ascertained employing agar diffusion and colorimetric MTT assay methods. A checkerboard assay was carried out using clove oil and amphotericin B against C. auris. Results: Eugenol was the major compound identified in CO at a concentration of 80.09%. AmB-loaded NEs exhibited particle sizes smaller than 50 nm and a polydispersity index below 0.25. The optimal Ne (NEMLB-05) remained stable after 150 days of storage at 4 °C. It exhibited rapid release within the first 24 h, followed by a slow and controlled release up to 96 h. NEMLB-05 more effectively inhibited C. auris compared to free AmB and also demonstrated greater activity against C. albicans, S. schenckii, and S. brasiliensis. Clove oil and amphotericin B presented synergism inhibiting the growth of C. auris. Conclusions: The selected CO-in-water NEs containing AmB demonstrated promising potential as a topical therapeutic alternative for treating fungal infections. Full article

Ferroptosis, a regulated form of cell death driven by iron accumulation and lipid peroxidation, contributes to oxidative stress-related skin damage. This study evaluates the antioxidant and anti-inflammatory effects of a nanoformulation derived from an Annurca apple callus extract in an in vitro model of ferroptosis using human keratinocytes (HaCaT cells). A hydroalcoholic extract from light Annurca apple callus (LCE) was nanoformulated with Pluronic^® F127 and Soluplus^® to enhance stability and bioavailability. The resulting nanoformulation (NF-LCE) exhibited optimal particle size (103.17 ± 0.87 nm), polydispersity index (0.21 ± 0.00), and zeta potential (−1.88 ± 0.64 mV). Iron overload (100 µM) was employed to induce oxidative stress and inflammation in HaCaT cells, resulting in elevated levels of inflammatory markers (COX2, IL-6, TNF-α) and a diminished antioxidant response, as indicated by decreased expression of GPX4 and Nrf2. NF-LCE treatment restored GPX4 and Nrf2 levels (~0.8-fold increase, p < 0.05) while significantly reducing COX2 (36.6%, p < 0.01), IL-6 (79.6%, p < 0.0001), and TNF-α (30.9%, p < 0.1). These results suggest NF-LCE as a promising therapeutic strategy for mitigating ferroptosis-induced skin damage, warranting further investigation in advanced skin models and clinical applications. Full article

Black phosphorus (BP) nanoflakes have attracted interest as an antimicrobial material for wound healing and implant-associated infections due to their bactericidal activity without the use of antibiotics. Hydrogels are frequently used as a delivery system; however, most research uses photonic activation in the form of near-infrared (NIR) laser stimulation to cause rapid BP degradation, reactive oxygen species (ROS) generation, and a localized photothermal effect. For implant-coating applications, using NIR laser stimulation could be challenging in practice, especially for porous orthopedic implants. This article investigates whether BP nanoflakes, suspended in Pluronic F127 (F127) hydrogels, remain effective against Staphylococcus aureus without photonic activation. The experimental results showed 89.4 ± 7.6% bacterial inhibition from BP nanoflakes at a 5120 µg/mL concentration via passive diffusion in F127; however, it could not kill all the bacteria present. It is hypothesized that the F127 gel interface could create a barrier between the bacteria, which continue to multiply in media, and the antimicrobial black phosphorus compound, which degrades in the F127. Full article

This study enhanced the gelatin-based hydrogel formulation by incorporating tannic acid, triblock copolymer Pluronic F-127, and phytic acid to improve its physicochemical properties. The swelling behaviour of these hydrogels was evaluated in phosphate buffer solution at selected pH levels. Morphological and thermal properties of the investigated hydrogels were analysed using scanning electron microscopy, thermogravimetric analysis coupled with mass spectrometry, and differential scanning calorimetry. Fourier transform infrared spectroscopy was employed to investigate the chemical structure of the optimal hydrogel. Tannic acid was recognised as a key component responsible for significant improvements in the hydrogel’s overall properties, including greater swelling capacity in phosphate buffer solution, a more defined porous structure, enhanced thermal stability (with a melting point above physiological conditions), significantly increased mechanical strength, elasticity, and overall robustness, as well as stability of the hydrogel network structure. These enhancements make the gelatin-based hydrogels more suitable for biomedical applications that demand high durability. Full article

Background/Objectives: Lipoxins, particularly Lipoxin A4 (LXA4), are endogenous lipid mediators with potent anti-inflammatory and pro-resolving properties, making them promising candidates for the treatment of inflammatory and neurodegenerative disorders. However, their therapeutic application is limited by poor stability and bioavailability. This study aimed to develop and characterize nanomicelles encapsulating LXA4 (nano-lipoxin A4) to improve its pharmacological efficacy against Alzheimer’s disease (AD), a neurodegenerative condition marked by chronic inflammation and beta-amyloid (Aβ) accumulation. Methods: Nano-lipoxin A4 was synthesized using Pluronic F-127 as a carrier and characterized in terms of morphology, physicochemical stability, and in vitro activity against Aβ fibrils. Dissociation of Aβ fibrils was assessed via Thioflavin-T fluorescence assays and transmission electron microscopy. In vivo biodistribution and pharmacokinetic profiles were evaluated using technetium-99m-labeled nano-lipoxin A4 in rodent models. Hepatic biochemical parameters were also measured to assess potential systemic effects. Results: In vitro studies demonstrated that nano-lipoxin A4 effectively dissociated Aβ fibrils at concentrations of 50 nM and 112 nM. Electron microscopy confirmed the disruption of fibrillar structures. In vivo imaging revealed predominant accumulation in the liver and spleen, consistent with reticuloendothelial system uptake. Pharmacokinetic analysis showed a prolonged half-life (63.95 h) and low clearance rate (0.001509 L/h), indicating sustained systemic presence. Biochemical assays revealed elevated liver enzyme levels, suggestive of increased hepatic metabolism or potential hepatotoxicity. Conclusions: Nano-lipoxin A4 exhibits significant therapeutic potential for Alzheimer’s disease through effective modulation of Aβ pathology and favorable pharmacokinetic characteristics. However, the elevation in liver enzymes necessitates further investigation into systemic safety to support clinical translation. Full article

Mild to moderate pain for a few hours to several days post-piercing is normal, and the pain is usually accompanied by swelling, redness, and warmth due to the inflammatory response. Cool compresses and over-the-counter analgesics (e.g., NSAIDs) can ease mild discomfort. However, oral NSAIDs may have systemic side effects; for this reason, we propose a topical anti-inflammatory approach. Four pranoprofen-loaded gels were created using different gelling agents: Sepigel^® 305 (PF-Gel-Sep), Carbopol^® 940 (PF-Gel-Car), Pluronic^® F-68 (PF-Gel-Plu), and Lutrol^® F-127 (PF-Gel-Lut). The gels were assessed for pH, morphology, FT-IR spectroscopy, rheological properties, spreadability, swelling and degradation, drug release kinetics, skin permeation (cow and human skin), irritation potential (HET-CAM assay), and impact on skin barrier function (TEWL and SCH). The gels exhibited varied rheological properties with PF-Gel-Car showing high viscosity and PF-Gel-Plu very low viscosity. All gels had similar spreadability with PF-Gel-Lut showing the highest. PF-Gel-Car showed the highest amounts of PF released, whereas PF-Gel-Plu led to the highest amount of pranoprofen retained in human and bovine skin. The HET-CAM assay indicated that none of the PF-Gels were irritating. Additionally, PF-Gel-Car and PF-Gel-Plu showed no cytotoxic effects on HaCaT cells. In vivo testing on mice showed that PF-Gel-Car prevented inflammation, while the rest of the gels were able to revert it in 25 min. Skin tolerance tests revealed the gels did not affect TEWL, and some gels improved SCH. The study successfully formulated and characterized four PF-loaded topical gels with potential to be used as an alternative for treating inflammation from piercings and ear tags. Full article

Nickel-decorated carbocatalysts were synthesized by the evaporation-induced self-assembly (EISA) method. The influence of the metal content and pyrolysis temperature upon the photoactivity was assessed through rhodamine B degradation under UV irradiation. The characterization revealed a mesoporous framework with a granular morphology composed of amorphous carbon, where the pyrolysis temperature influenced the metal dispersion on the carbon surface. The primary metallic phases consisted of elemental nickel crystallites and nickel carbide phases. The kinetic parameters for adsorption and dye photodegradation under UV irradiation were determined and compared to TiO₂-P25. Correlations were found between the adsorption parameters, photocatalytic activity, and nickel content, the pyrolysis method (one-step vs. two-step pyrolysis), and the pyrolysis temperature. The sample with a 1:1:0.25 tannin/Pluronic^®F-127/Ni weight ratio pyrolyzed at 700 °C exhibited the highest photoactivity, achieving rhodamine B degradation rates up to 68 and 2.5 times greater than photolysis and TiO₂-P25. In terms of the normalized weight of the catalysts, it can be concluded that the present Ni-based catalysts are up to two orders of magnitude more photoactive than TiO₂-P25 under UV irradiation, opening a door for indoor UV-driven photoreactors. These findings demonstrate that the EISA method is an effective, low-cost, and ecofriendly approach for synthesizing Ni-decorated carbocatalysts. Full article

Despite extensive efforts, no highly effective antiviral molecule exists for treating moderate and severe COVID-19. Nanotechnology has emerged as a promising approach for developing novel drug delivery systems to enhance antiviral efficacy. Among these, polymeric nanomicelles improve the solubility, bioavailability, and cellular uptake of therapeutic agents. In this study, Pluronic F127-based nanomicelles were developed and evaluated for their antiviral activity against SARS-CoV-2. The nanomicelles, formulated using the direct dissolution method, exhibited an average size of 37.4 ± 8.01 nm and a polydispersity index (PDI) of 0.427 ± 0.01. Their antiviral efficacy was assessed in SARS-CoV-2-infected Vero E6 and Calu-3 cell models, where treatment with a 1:2 dilution inhibited viral replication by more than 90%. Cytotoxicity assays confirmed the nanomicelles were non-toxic to both cell lines after 72 h. In SARS-CoV-2-infected Calu-3 cells (human type II pneumocyte model), treatment with Pluronic F127-based nanomicelles containing atazanavir (ATV) significantly reduced viral replication, even under high MOI (2) and after 48 h, while also preventing IL-6 upregulation. To investigate their mechanism, viral pretreatment with nanomicelles showed no inhibitory effect. However, pre-exposure of Calu-3 cells led to significant viral replication reduction (>85% and >75% for 1:2 and 1:4 dilutions, respectively), as confirmed by transmission electron microscopy. These findings highlight Pluronic F127-based nanomicelles as a promising nanotechnology-driven strategy against SARS-CoV-2, reinforcing their potential for future antiviral therapies. Full article

The fluorenyl methyl oxycarbonyl phenylalanyl-phenylalanine methyl ester (Fmoc-Phe-Phe-Ome) was synthetized using the liquid phase synthesis strategy. This derivative was separated by hydrophobic interaction chromatography, its purity was analyzed by RP-HPLC and it was characterized by mass spectrometry. This extremely hydrophobic peptide conjugate was incorporated into aqueous solutions of Pluronic^® F127 at low temperatures (below 10 °C). The temperature induced sol–gel transition was investigated by rheological measurements. A delay of the sol–gel transition, caused by the presence of low concentrations of Fmoc-Phe-Phe-Ome (up to 1%), enables better control of the gelation process. The viscoelastic properties of hybrid networks were investigated at 37 °C in different shear conditions. The Pluronic/peptide systems reported herein provide promising alternatives for developing innovative injectable gels as suitable platforms in cancer treatment. Full article