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Staphylococcus aureus (S. aureus) is a Gram-positive bacterium that causes infections ranging from mild superficial cases to more severe, potentially fatal conditions. Many photosensitisers used in photodynamic therapy are more effective against superficial infections due to limitations in treating deeper tissue infections. Recently, attention to this bacterium has increased due to the emergence of multidrug-resistant strains, which complicate antibiotic treatment. As a result, alternative therapies, such as antimicrobial photodynamic therapy (PDT), have emerged as promising options for treating non-systemic infections. PDT combines a photosensitiser (PS) with light and oxygen to generate free radicals that destroy bacterial structures. This systematic review evaluates the effectiveness of PDT delivered via different types of hydrogels in treating wounds, burns, and contamination by S. aureus. Following PRISMA 2020 guidelines, a bibliographic search was conducted in PubMed, Web of Science, and Scopus databases, including articles published in English between 2013 and 2024. Seven relevant studies were included, demonstrating evidence of PDT use against S. aureus in in vitro and in vivo studies. We concluded that PDT can effectively complement antimicrobial therapy in the healing of wounds and burns. The effectiveness of this technique depends on the PS used, the type of hydrogel, and the lesion location. However, further in vivo studies are needed to confirm the safety and efficacy of PDT delivered via hydrogels.

High-quality water availability is substantial for sustaining life, so its contamination presents a serious problem that has been the focus of several studies. The presence of heavy metals, such as cadmium, is frequently studied due to the increase in the contamination levels caused by fast industrial expansion. Cadmium ions were removed from aqueous solutions at pH 7.0 by chitosan-magnetite (ChM) xerogel beads and chitosan-FeO (ChF) xerogel beads in batch systems. Kinetic studies were best modeled by the Elovich model. The adsorption isotherms obtained showed an inflection point suggesting the formation of a second layer, and the BET model adjusted to liquid-solid systems was adequate for the description of the experimental data. Maximum uptake capacities of 36.97 ± 0.77 and 28.60 ± 2.09 mg Cd/g xerogel were obtained for ChM and ChF, respectively. The studied composites are considered promising adsorbent materials for removing cadmium ions from aqueous systems.

Rheumatoid arthritis, a chronic autoimmune disorder affecting millions worldwide each year, poses a significant threat due to its potential for progressive joint damage and debilitating pain if left untreated. Topical anti-inflammatory and analgesic treatments offer localized relief with reduced systemic side effects compared to conventional oral therapies, making them a promising option for managing rheumatoid arthritis. Therefore, the current study endeavored to formulate a microemulsion gel formulation loaded with diclofenac and curcumin for topical administration in the management of rheumatoid arthritis, utilizing Tea tree oil. The ratio of surfactant and cosurfactant was 4:1, assessed by pseudoternary phase diagram on the basis of the maximum emulsification region. The microemulsion underwent optimization using a Central Composite Rotatable Design (CCRD) with constraints of minimum particle size, polydispersity index, and maximum transmittance. The Curcufenac-T microemulsion had a particle size, polydispersity index (PDI), and transmittance of 151.82 ± 15.9 nm, 0.287 ± 0.021, and -5.78 ± 0.26 mV, respectively. DSC analyses confirmed the stability and compatibility of diclofenac and curcumin within the formulation. The microemulsion was changed into gel form by incorporating 1% carbopol-934. Skin permeation analysis revealed that the percentage of diclofenac permeated at 0.5 h from Curcufenac-T microemugel and the conventional gel was 12.1% and 3.9%, respectively, while at 12 h, the rates were 82.6% and 34.2%, respectively. In vitro permeability demonstrated significant potential for the effective delivery of diclofenac and curcumin to targeted sites, compared to conventional gel. Therefore, it was deduced that the Tea tree oil integrated diclofenac and curcumin microemulsion gel could enhance the effectiveness of diclofenac and serve as a promising vehicle for rheumatoid arthritis treatment.

The development of new biomaterials for musculoskeletal tissue repair is currently an important branch in biomedicine research. The approach presented here is centered around the development of a prototypic synthetic glycerogel scaffold for bone regeneration, which simultaneously features therapeutic activity. The main novelty of this work lies in the combination of an open meso and macroporous nanocrystalline cellulose (NCC)-based glycerogel with a fully biocompatible microporous bioMOF system (CaSyr-1) composed of calcium ions and syringic acid. The bioMOF framework is further impregnated with a third bioactive component, i.e., ibuprofen (ibu), to generate a multifold bioactive system. The integrated CaSyr-1(ibu) serves as a reservoir for bioactive compounds delivery, while the NCC scaffold is the proposed matrix for cell ingrowth, proliferation and differentiation. The measured drug delivery profiles, studied in a phosphate-buffered saline solution at 310 K, indicate that the bioactive components are released concurrently with bioMOF dissolution after ca. 30 min following a pseudo-first-order kinetic model. Furthermore, according to the semi-empirical Korsmeyer-Peppas kinetic model, this release is governed by a case-II mechanism, suggesting that the molecular transport is influenced by the relaxation of the NCC matrix. Preliminary in vitro results denote that the initial high concentration of glycerol in the NCC scaffold can be toxic in direct contact with human osteoblasts (HObs). However, when the excess of glycerol is diluted in the system (after the second day of the experiment), the direct and indirect assays confirm full biocompatibility and suitability for HOb proliferation.

Lost circulation is one of the important problems that restricts the speed and efficiency of oil and gas drilling and production. In this study, a resin plugging system was successfully developed for lost circulation formation. The resin plugging system showed excellent performance under high temperature and pressure conditions. The experimental results showed that the compressive strength of the resin plugging material can reach 9.23 MPa after curing, which is significantly higher than that of the traditional polymer gel material. The resin material can achieve effective curing in the temperature range of 60 °C to 100 °C, and the curing time decreases with the increase of temperature and only needs 3.46 h at 140 °C. The microstructure results showed that the resin material can form a chain or three-dimensional network structure after curing, which can effectively increase the toughness and strength of the cured plugging layer. Infrared and thermogravimetric analysis further confirmed the thermal stability of the chemical bonds in the material, and the initial decomposition temperature was about 241 °C, indicating that it had good thermal stability at about 300 °C. In addition, the effects of curing temperature, salinity, and drilling fluid pollution on the properties of the resin plugging agent were also investigated. The results showed that curing agent dosage and curing temperature are the key factors affecting curing time, while salinity and drilling fluid pollution affect the curing strength and overall properties of the materials. After adding 20% KCl polysulfonate drilling fluid, the compressive strength of the consolidated body decreased to 4.55 MPa. This study can provide an efficient and reliable plugging solution for malignant loss formation.

A fracture-related infection (FRI) is a severe complication of an orthopedic trauma, often leading to challenging treatments and poor outcomes. The surgical strategies are typically categorized into one-stage or two-stage procedures, with the use of systemic and local antibiotics being crucial for infection management. This study assessed the efficacy of an antibiotic-loaded hydrogel (ALH) applied over the internal fixation devices for treating FRIs, comparing the outcomes between the one-stage (OS) and two-stage (TS) reconstructions. This retrospective study included 17 patients with an FRI treated using the ALH at a single center. The patients were divided into OS and TS reconstruction groups. The data on demographics, surgical procedures, antibiotic regimens, and outcomes were collected. The primary and secondary outcomes included the infection cure rate, bone union, complications, and reoperation rates. Among the 17 patients (mean age 48.5 years, 16 males), infections were predominantly in the tibia, with 12 chronic and 5 acute cases. Seven patients had monomicrobial infections, and nine had multidrug-resistant pathogens. No significant differences were found between the OS and TS groups in terms of the infection cure rate, bone union, or complications. One patient in the OS group experienced an infection recurrence, and bone healing was achieved in all but one case. Additional complications included delayed wound closure in two cases and implant failure in one case, requiring a reoperation. The ALH demonstrated potential as an effective local antibiotic treatment for FRIs, particularly in the one-stage reconstructions, allowing for a safe application of internal fixation devices. However, further research with larger sample sizes and longer follow-ups is needed to validate these findings.

Converting solar energy into fuels/chemicals through photochemical approaches holds significant promise for addressing global energy demands. Currently, semiconductor photocatalysis combined with redox techniques has been intensively researched in pollutant degradation and secondary energy generation owing to its dual advantages of oxidizability and reducibility; however, challenges remain, particularly with improving conversion efficiency. Since graphene's initial introduction in 2004, three-dimensional (3D) graphene-based photocatalysts have garnered considerable attention due to their exceptional properties, such as their large specific surface area, abundant pore structure, diverse surface chemistry, adjustable band gap, and high electrical conductivity. Herein, this review provides an in-depth analysis of the commonly used photocatalysts based on 3D graphene, outlining their construction strategies and recent applications in photocatalytic degradation of organic pollutants, H₂ evolution, and CO₂ reduction. Additionally, the paper explores the multifaceted roles that 3D graphene plays in enhancing photocatalytic performance. By offering a comprehensive overview, we hope to highlight the potential of 3D graphene as an environmentally beneficial material and to inspire the development of more efficient, versatile graphene-based aerogel photocatalysts for future applications.

Origanum vulgare ssp. hirtum essential oil (OEO) is a natural oil with high therapeutic potential. For some applications, however, the development of novel formulations is still needed to improve the bioavailability and stability of OEO. In this study, we describe the fabrication of an original nanocomposite hydroxypropyl cellulose (HPC) physical hydrogel, containing OEO-loaded polymeric micelles, for topical delivery. The concentration of the main active compounds of OEO-carvacol and thymol-was determined using gas chromatography (GC) analysis. OEO was first encapsulated into Pluronic F127 micelles, and then embedded into HPC gel. Micellar and gel formulations of pure polymers and OEO-containing systems were characterized by dynamic light scattering (DLS) and rheology measurements, respectively. Selected formulations were evaluated for cytotoxicity and antiproliferative activity. The hydrogel formulation of HPC with micellar OEO (8% HPC, 2% F127, 1% OEO) exhibited sustained release of the oil and selectivity towards SH-4 tumor cells (an in vitro model of melanoma).

This study investigates the development and characterization of a novel composite hydrogel composed of polyacrylamide (PAAm), starch, and gelatin for use as an amoxicillin delivery system. The optical properties, swelling behavior, and drug release profile of the composite hydrogel's were studied to evaluate its efficacy and potential applications. UV-visible spectroscopy was employed to determine the optical properties, revealing significant transparency in the visible range, which is essential for biomedical applications. The incorporation of starch and gelatin into the polyacrylamide matrix significantly enhanced the hydrogel's swelling capacity and biocompatibility. Studies on drug delivery demonstrated a sustained release profile of amoxicillin in simulated gastrointestinal fluids, which is essential for maintaining therapeutic levels for a prolonged amount of time. The results indicate that the composite hydrogel of PAAm/starch/gelatin has good swelling behavior, appealing optical characteristics, and a promising controlled drug release mechanism. These results point to this hydrogel's considerable potential as a drug delivery method, providing a viable path toward enhancing the medicinal effectiveness of amoxicillin and maybe other medications.

Gelatin is a promising biopolymer for edible coatings thanks to its low cost and gelling properties. However, its weak mechanical properties limit its use. This study aimed to develop a gelatin coating with tomato extract, analyzing its antioxidant activity and rheological properties for food applications. Gelatin concentrations (2, 5, and 7%) were evaluated, and it was determined that 7% with 7.5% glycerol was the optimal mixture. Three concentrations of tomato extract (0.5, 1, and 1.5%) were added, and antioxidant activity was evaluated using the ABTS technique, as well as the interaction of components through FT-IR and physicochemical analysis. The results showed that there were no significant differences in terms of their physicochemical characterization, maintaining a pH of 5 and a yellowish hue. The FT-IR spectra indicated there were hydrogen bond interactions between gelatin and the extract. The antioxidant capacity was higher with the 1.5% extract, achieving an inhibition of 58.9%. It was found that the combination of the different materials used improved the rheological (specifically the viscosity and stability of the material) and antioxidant properties of the gelatin. These findings suggest that modified gelatin coatings may be effective in extending the shelf life of foods.