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This investigation presents an easy-to-implement fabrication process of a flexible sponge composite from polydimethylsiloxane (PDMS) decorated with mesoporous titanium dioxide (MTiO2)/nickel ferrite (NiFe2O4) as a novel photocatalyst system. A sacrificial template was used to fabricate a permeable PDMS structure with pores size varied from 10 to 150 μm. A solution containing different concentrations of MTiO2/NiFe2O4 is used to decorate the surface and slits walls of porous PDMS. FTIR analysis indicated that the Ti–O–Si bonds are the dominant interaction between PDMS and MTiO2/NiFe2O4. Furthermore, Ultimate Tensile Strength (UTS), SEM/EDS, HRTEM, diffuse reflectance spectroscopy (DRS), and vibrating sample magnetometer (VSM) analysis were performed to evaluate the PDMS incorporated Nano composite. In order to optimize the photocatalytic properties of PDMS–MTiO2/NiFe2O4 composite, the dispersion of different MTiO2/NiFe2O4 mass ratios in PDMS sponge is examined. The discoloration of contaminated methyl orange (MO) on sponge composite under solar simulated irradiation indicates the fast degradation of MO on PDMS–MTiO2/NiFe2O4 (70:30). The surface morphology, roughness, and wettability evaluation of composites revealed the active surface insertion of nanoparticles. The photocatalytic degradation mechanism was indirectly studied using scavengers to determine the OH · , h vb + , e cb - , and O 2 · - progressive species. The advantages of combining MTiO2/NiFe2O4 Nano catalyst with porous PDMS structure would offer a facile separation of catalyst from contaminant. The recyclability indicates the promising applications of these composites for efficient wastewater treatment. [ABSTRACT FROM AUTHOR]

In this paper, NiFe2O4 nanoparticles were synthesized by a solution plasma method. The anode material was made from iron and nickel powders by Spark Plasma Sintering process. By discharging on the anode's surface in the solution, a plasma was formed on the electrode surface, and nanosize particles detached from the electrode and immediately oxidized into a ferrite spinel. The NiFe2O4 nanoparticles were coated with polyethylene glycol, and then the heating generation of specimens under a magnetic field and their cytotoxicity were studied. Before the coating, the nanoparticles have a particle size of less than 12 nm with a specific surface area of 55.2 m2/g and a saturation magnetism of 42.2 emu/g. Coated nanoparticles using polyethylene glycol affect the magnetic properties, thermal properties, and cytotoxicity of nickel ferrite nanoparticles. The formed PEG coating on the surface of NiFe2O4 reduced the saturation magnetization and the produced heat in the hyperthermia process. Cytotoxicity tests have been carried out through MTT and flow cytometry. After coating the nickel ferrite nanoparticles with PEG, the percentage of cell viability increased from 86 to 99%. The results showed that the PEG-coated NiFe2O4 nanoparticles are suitable for medical applications with minimum cytotoxicity. [ABSTRACT FROM AUTHOR]

Semiconductors as effective photocatalysts and antibacterial agents are an attractive class of materials for water treatment. Composites of g-C3N4 and WO3 were designed via a novel mixing of sol-gel and calcination techniques to achieve a better photocatalyst with effective antibacterial properties. The specimens were examined using TEM, X-ray diffraction, FTIR, and UV-vis diffuse reflection spectroscopy. To investigate the photocatalytic properties of the manufactured samples, the photodegradation of methylene blue was evaluated. Studies were also conducted on the antibacterial properties of synthesized materials. The findings showed that the g-C3N4/WO3 revealed a higher photodegradation yield than pristine g-C3N4. The photodegradation yield of samples with 15wt.% of WO3 was up to 3.7 times higher than that of pure g-C3N4. The Z-scheme mechanism may be the reason for the higher electron and hole separation that results from the heterojunction formation between WO3 nanoparticles and g-C3N4 surfaces. The produced g-C3N4/15wt.%WO3 specimen exhibited effective antibacterial characteristics against Escherichia coli and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

For achieving a desirable thin film composite (TFC) membrane, accurate selection of raw materials, appropriate process, and manufacturing method for a homogenous dispersion are obligatory. In this study, the manufacturing and characterization of the nanofiltration membranes modified with cellulose/copper oxide nanoparticles for removing cadmium from water were studied. Thin films of nanocomposite membranes were prepared with surface polymerization. The manufactured membranes with different concentrations of copper oxide (0.1, 0.5, and 1 weight percent) and nanocellulose (0.01, 0.05, and 0.1 weight percent) were prepared. At the end of the process and passing for 60 minutes, the pure membrane's water flux was 238 L/m2.hr. The minimum content of the passing water flux for membrane with 1% CuO and nanocellulose 0.1% (weight percent) was 148 L/m2 hr. The cadmium removal efficiency increases by increasing pH from 2 to 6 for nanocomposite membranes. By increasing pH from 6 to 8, removing cadmium decreases. The cadmium removal of 94% was obtained for the membrane modified with 0.1% CuO and 0.1% nanocellulose. According to the antibacterial test results, an important inhibitory ring is formed around the membrane with a concentration of 1% CuO, which shows this membrane has significant antibacterial properties against Escherichia coli. [ABSTRACT FROM AUTHOR]

In the present study, Co1-xNixCr2O4 spinel nanopigment was synthesized by the polyacrylamide gel method. The effects of nickel substitution on morphology, crystal structure, and optical properties were investigated. The powders were characterized using X-ray diffraction, field emission scanning electron microscope, differential thermal analysis, Fourier transform infrared spectroscopy, and ultraviolet-visible spectroscopy. XRD patterns showed characteristic peaks of the spinel structure corresponding to the cobalt chromate phase. The ultraviolet-visible spectrum showed two absorption bands at 613 and 656 nm related to the charge transfer of spin ion Co2+ at the tetrahedral position and a change in the absorption spectrum with the increasing nickel content. Besides, TEM results revealed an average particle size of 22 nm for the Co0.6Ni0.4Cr2O4 sample. CIE-Lab was used to evaluate the color characteristics of the pigments. In this evaluation, L* depicts lightness. The a* and b* parameters are the four colors of human vision include red, green, blue, and yellow. Colorimetric results indicated with the substitution of nickel in the structure of cobalt chromate, its brightness (L*) increased, a* became more negative (more green) and b* tended to be more positive (more yellow). Highlights: Co1–xNixCr2O4 nanopigment was synthesized by the polyacrylamide gel method. TEM results revealed an average particle size of 22 nm for the Co0.6Ni0.4Cr2O4 sample. Nickel substitution reduced the size of the synthesized powder. With substitution of nickel, L* increased, a* became more negative, and b* tended to be more positive. [ABSTRACT FROM AUTHOR]

In the present research, ZnO-ZnWO nanocomposite was synthesized by a surfactant assisted microemulsion method. The characteristics of ZnO-ZnWO were characterized using various analytical methods. As the amount of ZnWO was increased in the composite up to 30 wt%, the particle size decreased. Adding further ZnWO resulted in an increase in the grain size. A shift in the energy band gap value from 3.2 to 3.16 eV was observed in the samples by adding 30 wt% ZnWO. The photocatalytic activity of the prepared nanocatalysts was investigated via photodegradation of methylene blue. The samples obtained from ZnO-30 wt% ZnWO heterojunction composite showed the highest activity with 96% photodegradation efficiency. [ABSTRACT FROM AUTHOR]

The aim of this work is to describe the production and assessment of the electroless properties of nickel-boron-vanadium carbide (Ni-B-VC) composite coating on CK45 steel substrate. For this porpose, Ni-B and Ni-B-VC deposits were applied on CK45 steel substrate through electroless method. Following sample preparation under optimum conditions, their characterisation was carried out by XRD, SEM and EDS analysis. Afterward, all coated samples were heat treated at 400°C, which resulted in transformation of the coatings structures from amorphous to crystalline. The hardness of the samples cross section was measured before and after heat treatment by a microhardness tester in the form of hardness profile test. The hardness results indicated an increase of hardness after heat treatment due to the formation of nickel boride hard phase in the coatings after heat treatment. To study the tribological behavior of the coatings, wear tests were performed by a pin-on-disk instrument. The obtained results revealed that by adding vanadium carbide particles to the electroless Ni-B coating, the hardness of these coatings increases to about 350 Vickers. Also, the hardness increase leads to an approximately 57% improvement in wear resistance of the composite coating in comparison with the Ni-B coating. [ABSTRACT FROM AUTHOR]

The purpose of this study is to define the preparation of CoAl2O4 as a nano-ceramic blue pigment via the polyacrylamide gel method. The powders were studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), thermo-gravimetric (TG) and differential thermal analysis (DTA), Fourier transform infrared spectroscopy (FTIR) and UV-visible techniques (UV-vis). Crystallized CoAl2O4 was obtained after calcination at 600 °C. The obtained powders in low temperature had a platy structure. By increasing the temperature, the layered structure was crushed into smaller pieces. The average particle size was approximately 18 nm. The UV-vis spectra presented three bands at 551, 590 and 628 nm attributed to the Co2+ spin transitions in tetrahedral sites. The results showed that a different calcination temperature causes a variation in the color and size of the particles. The temperature for obtaining blue CoAl2O4 was about 1000 °C. [ABSTRACT FROM AUTHOR]

Nanocrystalline Ba2+ added alumina/cobalt blue nanoceramic pigment was prepared using a polyacrylamide gel method. The samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and UV-vis spectroscopy. The XRD patterns indicated the characteristic peaks of the spinel structures related to the CoAl2O4 and BaAl2O4 phases with a good crystallinity. The crystallite sizes of spinels increased with the increase of barium content. The partial substitution of Co2+ by bigger ions like Ba2+ can cause a distortion in the unit cell compared to pure CoAl2O4 sample. UV-vis analysis showed that at a wavelength of 450 nm the absorbance of the sample was changed with the increase of Ba content and yielded a blue pigment with an improved color point. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) printing has facilitated the fabrication of customized scaffolds for the repair of complex bone defects. In this study, 3D-printed scaffolds composed of a mixture of polylactic acid-polyvinylpyrrolidone (PLA-PVP) incorporating different amounts of forsterite (F; Mg 2 SiO 4 ) nanoparticles were fabricated using fused deposition modeling (FDM) technique. The incorporation of PVP and F nanoparticles into the PLA scaffold significantly decreased the water drop contact angle. The mechanical properties of the PLA-PVP scaffold were enhanced with the addition of 10 % F nanoparticles, as the compressive yield strength increased from 10.8 to 16.0 MPa and the elastic modulus from 83.52 to 108.41 MPa. However, the addition of F nanoparticles increased the degradation rate of the PLA-PVP scaffold over 8 weeks. Importantly, the addition of 10 % F nanoparticles into the PLA-PVP scaffold improved bioactivity and formation of apatite deposits on the scaffold after 4 weeks of immersion in simulated body fluid. Moreover, the PLA-PVP/10F scaffold showed strong MG63 cell adhesion and proliferation, as well as promoting osteogenic differentiation of rat bone marrow mesenchymal stem cells. At last, these findings suggest the PLA-PVP/10F scaffold is a promising candidate for application in bone defect repair., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

3D printing, as a layer-by-layer manufacturing technique, enables the customization of tissue engineering scaffolds. Surface modification of biomaterials is a beneficial approach to enhance the interaction with living cells and tissues. In this research, a polylactic acid/polyethylene glycol scaffold containing 30 % bredigite nanoparticles (PLA/PEG/B) was fabricated utilizing fused deposition modeling (FDM) 3D printing. To modify the surface properties and facilitate the loading and release of therapeutics, the scaffold was coated with chitosan-polyethylene glycol (CS-PEG) nanofibers incorporating vancomycin (V) and insulin-like growth factor-1 (IGF1). The characterization was conducted using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The results demonstrated that the release of V (93.43 %) and IGF1 (95.86 %) from the fabricated scaffolds persisted for 28 days in a phosphate-buffered saline (PBS) solution. The release of V resulted in antibacterial activity against Staphylococcus aureus (S. aureus), forming an inhibition zone of 21.16 mm. Additionally, it was demonstrated that the release of IGF1 could counteract the adverse effect of V release on cell behavior, and enhance the adhesion and proliferation of MG63 cells. Preclinical in vivo studies conducted on a rat calvarial defect model validated that the bone repair was fully completed in the group treated with the fabricated scaffold within 8 weeks. Consequently, the scaffold designed in this study can serve as a versatile scaffold for achieving perfect repair of craniofacial defects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Tissue engineering has emerged as a promising substitute for traditional tissue repair methods. Nowadays, advancements in 3D printing technology have enabled the fabrication of customized scaffolds to support tissue regeneration. In the present study, a polylactic acid-polyvinylpyrrolidone 3D-printed scaffold containing 10 % forsterite was fabricated. Subsequently, lyophilized fucoidan microstructures loaded with sildenafil were filled the channels of this 3D-printed scaffold. The fabricated scaffold loaded with sildenafil was thoroughly characterized, revealing that 97.46 % of the loaded sildenafil was released in a sustained manner over 28 days. Furthermore, the biocompatibility of MG63 was evaluated through cell viability and adhesion tests. The findings indicated a direct and favorable influence on cell behavior. Based on the chicken chorioallantoic membrane assay, the fabricated scaffold significantly increases angiogenesis due to the sustained release of sildenafil. Moreover, in-vivo studies conducted on a rat model demonstrated that the 3D-printed scaffold was able to stimulate and accelerate the repair of calvarial defects within 8 weeks, and the amount of new bone tissue formation was significantly higher than that of other experimental groups. Based on the comprehensive in-vitro and in-vivo assessments, the scaffold with a macro- and microporous structure combined with the ability to release sildenafil is suggested as a potential candidate for repairing bone tissue, especially in the context of skull defects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Recently, the fabrication of personalized scaffolds with high accuracy has been developed through 3D printing technology. In the current study, polylactic acid/polyethylene glycol (PLA/PEG) composite scaffolds with varied weight percentages (0, 5, 10, 20 and 30 %) of bredigite nanoparticles (B) were fabricated using the 3D printing and then characterized through scanning electron microscopy and Fourier transform infra-red spectroscopy. The addition of B nanoparticles up to 20 wt% to PLA/PEG scaffold increased the compressive strength (from 7.59 to 13.84 MPa) and elastic modulus (from 142.42 to 268.33 MPa). The apatite formation ability as well as inorganic ion release in simulated body fluid were investigated for 28 days. The MG-63 cells viability and adhesion were enhanced by increasing the amount of B in the PLA/PEG scaffold and the osteogenic differentiation of the rat bone marrow mesenchymal stem cells was confirmed by alkaline phosphatase activity test and alizarin red staining. According to chorioallantoic membrane assay, the highest angiogenesis occurred around the PLA/PEG/B30 scaffold. In vivo experiments on a rat calvarial defect model demonstrated an almost complete recovery in the PLA/PEG/B30 group within 8 weeks. Based on the results, the PLA/PEG/B30 composite scaffold is proposed as an optimal scaffold to repair bone defects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Severe bleeding has caused significant financial losses as well as a major risk to the lives and health of military and civilian populations. Under some situations, the natural coagulation mechanism of the body is unable to achieve fast hemostasis without the use of hemostatic drugs. Thus, the development of hemostatic materials and techniques is essential. Improving the quality of life and survival rate of patients and minimizing bodily damage requires fast, efficient hemostasis and prevention of bleeding. Alginate is regarded as an outstanding hemostatic polymer because of its non-immunogenicity, biodegradability, good biocompatibility, simple gelation, non-toxicity, and easy availability. This review summarizes the basics of hemostasis and emphasizes the recent developments regarding alginate-based hemostatic systems. Structural modifications and mixing with other materials have widely been used for the improvement of hemostatic characteristics of alginate and for making multifunctional medical devices that not only prevent uncontrolled bleeding but also have antibacterial characteristics, drug delivery abilities, and curing effects. This review is hoped to prepare critical insights into alginate modifications for better hemostatic properties., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Skin is the largest organ of the human body, which acts as a protective barrier against pathogens. Therefore, a lot of research has been carried out on wound care and healing. Creating an ideal environment for wound healing and optimizing the local and systemic conditions of the patient play critical roles in successful wound care. Many products have been developed for improving the wound environment and providing a protected and moist area for fast healing. However, there is still high demand for new systems with high efficiency. The first generation of wound dressings merely covered the wound, while the subsequent/last generations covered it and aided in healing it in different ways. In modern wound dressings, the kind of used materials and their complexity play a crucial role in the healing process. These new systems support wound healing by lowering inflammation, exudate, slough, and bacteria. This study addresses a review of alginate/hyaluronic acid-based wound dressings developed so far as well as binary and ternary systems and their role in wound healing. Our review corroborates that these systems can open up a new horizon for wounds that do not respond to usual treatments and have a long curing period., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)