Tetraethoxysilane Research Articles

Controlled and rapid microreactor-assisted hydrolysis of sesame protein by a novel nanobiocatalyst; immobilized alcalase over activated sol–gel magnetic nanosupport

In this study, sesame cake was valorized to produce sesame protein hydrolysate (SPH) with improved functional and antioxidant properties using a recoverable nanomagnetic immobilized Alcalase (ALC); the process was accelerated in the microreactor through a controlled-hydrolysis technique. For this purpose, silica-coated magnetic nanoparticles (Fe3O4@SiO2) were synthesized and functionalized with tetraethoxysilane (TEOS), N-(trimethoxysilylpropyl) ethylenediamine (TMSED), and finally activated with glutaraldehyde (GLU) to produce Fe3O4@SiO2-TMSED-GLU. Immobilization efficiency of ALC was 88.78 % in the optimum conditions of ALC concentration (1.23 mg/mL), immobilization period (119.12 min), and temperature (38.93 °C). The successful synthesis of Fe3O4@SiO2-TMSED-GLU-ALC magnetic nanobiocomposite (MNBC) was approved using FTIR, XRD, VSM, FESEM, EDX, and elemental mapping. The effective immobilisation of the enzyme was responsible for the decrease in the intensity of Fe3O4 diffraction peaks (in XRD) in MNBC and a reduction in saturation magnetization (in VSM) following ALC immobilisation. Microreactor-intensified hydrolysis in the optimized conditions of MNBC = 4.85 wt%, reaction time = 54.10 s, and temperature = 46.95 °C, led to a degree of hydrolysis = 7.19 %. After 10 hydrolysis cycles, MNBC had relative activity > 80 %, due to the appropriate covalent bonding between the enzyme and the support and the short duration of the process. The produced SPH had superior foaming capacity (113.09 %) compared to sesame protein (76.34 %). The emulsion activity and emulsion stability of SPH were 28.78 m2/g and 56.43 min, respectively, which were higher than those of the sesame protein.

Site-Selective Deposition of Silica Nanoframes and Nanocages onto Faceted Gold Nanostructures Using a Primer-free Tetraethyl Orthosilicate Synthesis.

The Stöber method for forming spherical silica colloids is well-established as one of the pillars of colloidal synthesis. In a modified form, it has been extensively used to deposit both porous and protective shells over metal nanomaterials. Current best-practice techniques require that the vitreophobic surface of metal nanoparticles be primed with a surface ligand to promote silica deposition. Although such techniques have proved highly successful in forming core-shell configurations, the site-selective deposition of silica onto preselected areas of faceted metal nanostructures has proved far more challenging. Herein, a primer-free TEOS-based synthesis is demonstrated that is capable of forming architecturally complex nanoframes and nanocages on the pristine surfaces of faceted gold nanostructures. The devised synthesis overcomes vitreophobicity using elevated TEOS concentrations that trigger silica nucleation along the low-coordination sites where gold facets meet. Continued deposition sees the emergence of a well-connected frame followed by the lateral infilling of the openings formed over gold facets. With growth readily terminated at any point in this sequence, the synthesis distinguishes itself in being able to achieve patterned and tunable silica depositions expressing interfaces that are uncorrupted by primers. The so-formed structures are demonstrated as template materials capable of asserting high-level control over synthesis and assembly processes by using the deposited silica as a mask that deactivates selected areas against these processes while allowing them to proceed elsewhere. The work, hence, extends the capabilities and versatility of TEOS-based syntheses and provides pathways for forming multicomponent nanostructures and nanoassemblies with structurally engineered properties.

Engineering in ceramic albite morphology by the addition of additives: Carbon nanotubes and graphene oxide for energy applications

Abstract The synthesis of zeolite nanoparticles is studied comprehensively by adding an organic template as a reflux method, extracted from crystals. The zeolite nano-crystals are quite effectively synthesized by incorporating silica, organic template, and alkali metal. The tetrapropylammoniumhydroxide, tetrapropylammoniumbromide and tetraethyl orthosilicate (TEOS) as organic templates are added for the assistance of zeolite (albite) crystals. A cross-linker TEOS is also mixed. Adding carbon nanotubes and graphene oxide made the morphology of albite more interesting. Nucleation time is an important feature for the formation of albite crystals. The albite nano-shaped crystal is developed for instance when reaction time is less than 240 h, after this period crystal size increases with time. Batch 1 of zeolite is prepared with additives for testing its morphology, like surface area, particle size shape, and crystal geometry. The general trend (e.g., pore volume, percentage composition, particle size, geometry) of zeolite nano-crystal is explained by the help of robust techniques such as Fourier transform infrared spectroscopy, X-ray diffraction, Brunauer–Emmett–Teller, energy-dispersive X-ray spectroscopy, and scanning electron microscopy.

A transparent hydrophilic coating for long-lasting anti-fogging with self-cleaning and antibacterial properties

Transparent substrates with anti-fogging properties endowed by surface hydrophilic modification have been proved to applied in various fields. In this study, a superhydrophilic coating (PAT coating) was generated on glass substrate via dip coating technique using a solution comprising polyvinyl alcohol (PVA), alkyl polyglycoside (APG1214), and tetraethoxysilane (TEOS). The plentiful hydroxyl groups present in PVA and APG1214 endow the PAT coating with high hydrophilicity for excellent anti-fogging and self-cleaning properties, and facilitate to form a stable homogeneous hydrogen-bonded crosslinked network. Meanwhile, the in situ generated tetraethoxysilane hydrolysate (TEOH) from hydrolysis of TEOS acts as a crosslinker, which can covalently connect the organic components to the glass substrate. As a result, the resulting PAT coating displays excellent stability during various mechanical and chemical durability tests. In addition, the coating exhibits antibacterial adhesion properties owing to the broad-spectrum antibacterial property of APG1214. Importantly, the PAT coating can be easily prepared with readily available and economical raw materials through a simple method under mild conditions that does not require complicated separation and purification, thereby enabling its potential industrial application.

Investigation of the structural properties of Si4+-doped HAP coatings on Ti-6Al-4V substrate as a corrosion barrier in biomedical media

The coatings of co-substituted bioactives play an important role in stimulating biological and physical properties for biomedical applications. Hydroxyapatite (HAP), a mineral compound possessing a hexagonal structure, exhibits high thermodynamic stability under typical physiological conditions. In this experimental study, Si4+-doped HAP coatings with varying concentrations (2.5 %, 5 %, and 10 % wt) were prepared on a Ti-6Al-4V substrate using the spin-coating technique and extreme centrifugal force (2500 rpm). The coated samples were characterized by XRD, FTIR, AFM, FESEM, and EDS techniques. The presence of cracks and voids in the HAP coatings detrimentally affected the performance of the implants. Tetraethyl orthosilicate (TEOS) was used in the coatings to mitigate the cracks and voids. Polarization and EIS studies in the simulated body fluid (SBF) were used to assess the corrosion resistance of the coatings. The decrease in current density and the improved resistance to corrosion observed in the coated samples, as compared to the uncoated Ti-6Al-4V, demonstrate the corrosion-inhibiting effects of anodizing. The integration of Si4+ ions in the structure of HAP caused the size of nanoparticles to decrease from 16.23 nm to 11.67 nm, and the surface roughness of the produced coatings exhibited a decrease from 29.18 to 5.65 nm. In the Nyquist plots, the 5 % Si4+-doped HAP coating displayed the highest Rct value of 17.99 MΩ.cm2 compared to the bare Ti-6Al-4V with a resistance of 0.13 MΩ.cm2. The 5 % Si4+-doped HAP coating was chosen as the optimal sample based on the study results. The results of this work show that surface modification with Si4+-doped HAP coatings is a promising approach for improving the functionality of the Ti-6Al-4 V alloy for biomedical applications.

Application of High-Surface Tension and Hygroscopic Ionic Liquid-Infused Nanostructured SiO2 Surfaces for Reversible/Repeatable Anti-Fogging Treatment

Anti-fogging coatings/surfaces have attracted much attention lately because of their practical applications in a wide variety of engineering fields. In this study, we successfully developed transparent anti-fogging surfaces using a non-volatile and hygroscopic ionic liquid (IL), bis(hydroxyethyl)dimethylammonium methanesulfonate ([BHEDMA][MeSO3]), with a high surface tension (HST, 66.4 mN/m). To prepare these surfaces, a layer of highly transparent, superhydrophilic silica (SiO2) nano-frameworks (SNFs) was first prepared on a glass slide using candle soot particles and the subsequent chemisorption of tetraethoxysilane (TEOS). This particulate layer of SNFs was then used as the support for the preparation of the [BHEDMA][MeSO3] layer. The resulting IL-infused SNF-covered glass slide was highly transparent, superhydrophilic, hygroscopic, and had self-healing and reasonable reversible/repeatable anti-fogging/frosting properties. This IL-infused sample surface kept its excellent anti-fogging performance in air for more than 8 weeks due to the IL’s non-volatile, HST, and hygroscopic nature. In addition, even if the water absorption limit of [BHEDMA][MeSO3] was reached, the anti-fogging properties could be fully restored reversibly/repeatably by simply leaving the samples in air for several tens of minutes or heating them at 100 °C for a few minutes to remove the absorbed water. Our IL-based anti-fogging surfaces showed substantial improvement in their abilities to prevent fogging when compared to other dry/wet (super)hydrophobic/(super)hydrophilic surfaces having different surface geometries and chemistries.

Chitin-augmented wetting resistance and water-in-oil emulsion separation performance of silane-modified polyketone membrane

The utilization of membrane technology for separating water-in-oil (W/O) emulsions necessitates a membrane possessing high hydrophobic properties. However, the use of naturally hydrophobic membrane materials, such as polyvinylidene fluoride, is undesirable due to the persistence of fluorine-containing compounds in the environment. Polyketone (PK) membranes present a potential alternative, but their inherent hydrophilic properties can hinder the W/O emulsion separation process. To address this issue, hydrophobic modification of PK membranes can improve their performance in separating W/O emulsion. Natural hydrophobic materials like chitin offer a more sustainable alternative compared to synthetic materials. Chitin was introduced onto the membrane surface along with hexadecyltrimethoxysilane (HDTMS) subsequent to the initial reaction of the PK membrane with tetraethyl orthosilicate (TEOS). Comparative analysis revealed that the mixed chitin and HDTMS modification resulted in the lowest surface wettability compared to membrane modification using only TEOS, HDTMS, and chitin. Examination of membrane performance through toluene emulsion separation demonstrated increased permeability after modification, with permeate toluene purity over 99.8 %. Additionally, the chitin and silane-modified PK membrane exhibited a two-fold increase in filtration process permeability, indicating outstanding fouling resistance. These findings underscore the potential of natural compounds in imparting desired hydrophobic properties to membranes while minimizing reliance on synthetic materials.

Silicon-infused bacterial cellulose: in situ bioprocessing for tailored strength and surface characteristics

In this study we investigate the use of in situ bioprocessing for the production and surface modification of bacterial cellulose (BC) with silicon additives. The surface properties and tensile strength of the BC were studied and compared with plain BC. The effect the modification exhibited on the survivability of the bacteria was assessed by optical density measurements and found that the addition of the modification marginally slowed growth in the case of Tetramethyl orthosilicate (TMOS) and did not affect the growth in the case of Tetraethyl orthosilicate (TEOS). Characterisation of the modified BC was carried out using FTIR, EDX and confirmed the presence of silicon in the material. The width of fibres in the microstructure of BC was measured using SEM. Two different silicon modifications were used to modify the BC, it was shown that the TMOS modification decreased the tensile strength but that the TEOS increased the tensile strength of the BC fibres compared to plain BC. In addition, we found that the washing conditions of 1% NaOH (w/v), industrial methylated spirit (IMS), and deionised water (DI) showed some impact on the properties of the samples, particularly the IMS produced a reduced contact angle in the modified samples. However, the contact angle increased in the case of TEOS modification with the NaOH wash. In conclusion this study shows a novel method of modifying BC materials in-situ using silicon additives for increased tensile strength and the potential for tuneable hydro interactions.

Precision drug delivery through methotrexate and tofacitinib citrate encapsulated mesoporous silica scaffold

Background: Advancements in drug delivery aim to enhance outcomes while reducing adverse effects. Mesoporous silica nanoparticles (MSN) offer potential for targeted delivery due to their unique properties, including ordered pore structure, large surface area, and biocompatibility. Methods: MSN were synthesized using tetraethyl orthosilicate (TEOS) and Pluronic F127, then amine-functionalized with 3-aminopropyltriethoxysilane. Methotrexate and tofacitinib citrate were loaded via incipient wetness impregnation. Characterization included FTIR, particle size analysis, TEM, SEM, DSC, XRD, and BET analysis. Results: FTIR confirmed surface modification. Particle size analysis showed nanoscale dimensions. TEM and SEM depicted ordered mesoporous structures. DSC indicated drug crystallinity and MSN amorphism. XRD revealed reduced drug crystallinity in MSN. BET analysis demonstrated high MSN surface area and pore volume. Drug-loading efficiency was 62.44%. Conclusion: Comprehensive synthesis and characterization of MSN for targeted drug delivery were achieved successfully, highlighting their potential in overcoming conventional therapy limitations.

Effects of Cs-137 radiation on hydrophobic silica monolithic prepared by two precursors

Cesium (Cs-137) radiation energy was shined on two aerogel samples made from two different starting materials at room temperature and pressure three times a day for one hour, two hours, and twenty-four hours. G1 and G2 were used as silicic acid sources to fabricate the two different types of aerogel samples. G1 represents tetraethyl orthosilicate (TEOS), while G2 represents sodium silicate (Na2SiO3). Field emission scanning electron microscopy analysis revealed the morphological characteristics of the molecular bonds and the impact of irradiation on them. Fourier-transform infrared spectroscopy investigated the molecular bonds and their characterization before and after exposure to radiation. The samples made from TEOS at room temperature and pressure were not affected by radiation in either the FTIR or FESEM tests. However, the samples made from Na2SiO3 at room temperature and pressure showed that some of the peaks were disappearing because they were exposed to radiation. Also, the peaks of the CH3 functional group are associated with the hydrophobicity of the material. The homogeneity and uniformity for all samples are dominant, and the size of the colloidal particles is about 30-33 nanometers (nanometer structure), which is no different from the size of the particles before and after exposure to gamma rays.

Surface characterization of consolidated earthen substrates using an innovative multi-analytical strategy

This study evaluates the combined use of innovative non-destructive methods and standard laboratory techniques for assessing the surface effects of various consolidation treatments (i.e., bacterial biomineralization, alkaline activation, colloidal dispersions containing nanolime or nanosilica, and ethyl silicate as a standard) on earthen building materials. It demonstrates that novel portable equipment (i.e., portable digital microscope, air permeameter, and mobile surface (contact angle) analyzer) and advanced strategies for the application and data interpretation of conventional analytical and testing methods (i.e., scanning electron and confocal microscopy, Leeb hardness testing, and visible light spectrophotometry) can yield complementary and extremely valuable quantitative results for the evaluation of consolidation treatments on such complex substrates. Our multi-analytical approach allows a detailed characterization of surface and near-surface features of treated earthen mock-ups. It is possible to disclose significant differences in the film-forming propensity and in-depth distributions of consolidants and their effect on key properties such as surface roughness and appearance, permeability, water behavior, and mechanical properties. Even though, the substrate's inhomogeneity and surface texture has proven to be especially challenging, this methodology offers a promising strategy for long-term in-situ monitoring of treatment performance and weathering behavior of built heritage materials.

Multifunctional polyester-cotton fabrics with excellent flame retardancy, superhydrophobicity, antibacterial property and UV resistance

In this study, multifunctional polyester-cotton fabrics (PTCO) were constructed by gradually assembling polyethyleneimine phenyl phosphonate (POI) and different hydrophobic agents, respectively. The effect of different hydrophobic agents including tetraethyl orthosilicate, perfluorooctyltriethoxysilane (PFDTES), and hexadecyltrimethoxysilane on the thermal stability, flame retardancy, hydrophobic property, UV resistance and antibacterial property of PTCO/POI was investigated in detail. PTCO/POI-SiF had better flame retardancy due to the flame-retardant effect of PFDTES and POI, and the limiting oxygen index increased from 29.8 % to 31.2 %. The thermal oxidation stability of PTCO/POI-SiH and PTCO/POI-SiF was significantly improved in high temperatures, and the char residues at 700 °C were increased from 4.1 % to 7.6 % and 7.4 %. And PTCO/POI-SiH and PTCO/POI-SiF had excellent superhydrophobic properties with water contact angles of 151° and 162° and sliding angles of 4° and 3°. The ultraviolet protection factors of them were increased to 56.9 and 63.3, respectively, which had a good UV resistance. And both PTCO/POI-SiH and PTCO/POI-SiF had excellent antibacterial effects for E. coli and S. aureus. The breaking force, whiteness and moisture permeability of the finished fabrics had not been changed. Therefore, it is believed that PTCO/POI-SiH and PTCO/POI-SiF are promising for application in multifunctional fabrics.

Valorization of agriculture waste: Preparation of alkoxysilanes from mixed rice straw and rice husk ash

Synthesis of alkoxysilanes from renewable silica resources could promote their sustainability but remain grand challenges. Herein, we present a simple, effective strategy to synthesize tetraethyl orthosilicate (TEOS) directly from bio-derived silica through supercritical ethanol processing, where no catalyst nor additives are required. Crucially, calcination temperature is demonstrated to play a critical role in altering the structure of silica in rice husk ash (RHA), which directly influences its conversion activity to alkoxysilanes. Specifically, under optimized conditions at 280 °C and 1 h, RHA obtained at 400–625 °C calcination allows for an amorphous silica structure and as high as 85 mol% yield to alkoxysilanes. Moreover, the ash obtained from mixed rice straw and rice husk yields over 94 mol% alkoxysilanes, demonstrating the self-catalytic potential of the natural complexity of the ash. The effects of typical minerals contained in ash on the reaction are probed. It is revealed that potassium oxide is the main catalytic species in ash, which provide a suitable alkaline strength. The concentration of potassium ion exhibits a pronounced positive effect on catalyzing the synthesis of alkoxysilanes, and the co-existed phosphorus species exhibits promotional effect to TEOS selectivity. Furthermore, 29Si MAS NMR and Laplacian bond order analysis reveal that the cleavage of Si-O-Si bond predominates in the supercritical ethanol environment, providing a viable path for the production of TEOS.

Preparation and Characterization of Silica-Coated Sodium Alginate Hydrogel Beads and the Delivery of Curcumin

In this study, to address the defects of sodium alginate (SA), such as its susceptibility to disintegration, silica was coated on the outer layer of sodium alginate hydrogel beads in order to improve its swelling and slow-release properties. Tetraethyl orthosilicate (TEOS) was used as the hydrolyzed precursor, and the solution of silica precursor was prepared by sol-gel reaction under acidic conditions. Then SA–silica hydrogel beads prepared by ionic crosslinking method were immersed into the SiO2 precursor solution to prepare SA–silica hydrogel beads. The chemical structure and morphology of the hydrogel beads were characterized by XRD, FTIR, and SEM, and the results showed that the surface of SA–silica beads was successfully encapsulated with the outer layer of SiO2, and the surface was smooth and dense. The swelling experiments showed that the swelling performance effectively decreased with the increase of TEOS molar concentration, and the maximum swelling ratio of the hydrogel beads decreased from 41.07 to 14.3, and the time to reach the maximum swelling ratio was prolonged from 4 h to 8 h. The sustained-release experiments showed that the SA–silica hydrogel beads possessed a good pH sensitivity, and the time of sustained-release was significantly prolonged in vitro. Hemolysis and cytotoxicity experiments showed that the SA-silica hydrogel beads were biocompatible when the TEOS molar concentration was lower than 0.375 M. The SA–silica-2 hydrogel beads had good biocompatibility, swelling properties, and slow-release properties at the same time.

Protocrystallinity of Monodispersed Ultra-Small Templated Mesoporous Silica Nanoparticles.

Monodisperse and semi-faceted ultra-small templated mesoporous silica nanoparticles (US-MSNs) of 20-25 nm were synthesized using short-time hydrolysis of tetraethoxysilane (TEOS) at room temperature, followed by a dilution for nucleation quenching. According to dynamic light scattering (DLS), a two-step pH adjustment was necessary for growth termination and colloidal stabilization. The pore size was controlled by cetyltrimethylammonium bromide (CTAB), and a tiny amount of neutral surfactant F127 was added to minimize the coalescence between US-MSNs and to favor the transition towards internal ordering. Flocculation eventually occurred, allowing us to harvest a powder by centrifugation (~60% silica yield after one month). Scanning transmission electron microscopy (STEM) and 3D high-resolution transmission electron microscopy (3D HR-TEM) images revealed that the US-MSNs are partially ordered. The 2D FT transform images provide evidence for the coexistence of four-, five-, and sixfold patterns characterizing an "on-the-edge" crystallization step between amorphous raspberry and hexagonal pore array morphologies, typical of a protocrystalline state. Calcination preserved this state and yielded a powder characterized by packing, developing a hierarchical porosity centered at 3.9 ± 0.2 (internal pores) and 68 ± 7 nm (packing voids) of high potential for support for separation and catalysis.

Synthesis of Si3N4 powder with a controllable alpha/beta ratio by sol-gel assisted carbothermal reduction and nitridation

The controllable α/β ratio of Si3N4 powder was synthesized using tetraethyl orthosilicate (TEOS), glucose, MgCl2 and YCl3·6H2O by sol-gel assisted carbothermal reduction and nitridation (CRN). This study aimed to investigate the impact of various parameters, including a H2O/TEOS mol ratio of the sol, a C/Si mol ratio, sintering aids, and the temperature of CRN on the phase transformation of α-Si3N4. The results demonstrated that the H2O/TEOS ratio significantly influenced the relative content of α and β phase in Si3N4 by changing the morphological characteristics of SiO2. When the H2O/TEOS ratio was 100, β-Si3N4 powder with an approximate β content over 88 wt% was synthesized at 1500 °C. This remarkable phase transformation was likely facilitated by the eutectic liquid phase consisting of MgSiO3/Mg2SiO4. The SEM image revealed rod-like whiskers with a length around 1.4 μm for the β-Si3N4 grains. Due to the presence of liquid phase, the synthesis of spherical-like α-Si3N4 nano-powder with an α-phase content of 91 wt% was achieved at a lower temperature of 1450 °C, with an H2O/TEOS ratio of 15 and a C/Si ratio of 4. The size of the particles was about 70 nm due to the reduced reaction temperature. Furthermore, without the addition of any sintering aids or Si3N4 seeds, high purity α-Si3N4 with an α phase content approaching 96 wt% could be synthesized at 1500 °C, using an H2O/TEOS ratio of 15 and a C/Si ratio of 4. The resulting α-Si3N4 powder exhibited an extremely regular hexagonal prism shape with a length of approximately 2 μm.

Conversion of C8 aromatics over a dual-bed catalyst.

A dual-bed catalyst was prepared for the conversion of C8 aromatics. The upper bed layer consisted of ZSM-5 covered with SiO2, primarily utilized for ethylbenzene dealkylation. By employing tetraethyl orthosilicate (TEOS) as a deposition agent through the chemical liquid deposition (CLD) method, the modified ZSM-5 catalyst exhibited optimal catalytic performance at a TEOS addition of 0.6 g per gram of catalyst. The lower bed layer contained ZSM-39 catalyst, mainly employed for xylene isomerization reaction. ZSM-39 was synthesized using pyrrolidine as the template, and the best catalytic performance was achieved when the OH-/SiO2 molar ratio in the synthesis system was 0.05. The mass ratio between the upper and lower agents was maintained at 1 : 1. Compared to traditional single-bed ZSM-5 catalysts, the dual-bed catalyst demonstrated enhanced activity and selectivity.

Leaf on a Film: Mesoporous Silica-Based Epoxy Composites with Superhydrophobic Biomimetic Surface Structure as Anti-Corrosion and Anti-Biofilm Coatings.

In this study, a series of amine-modified mesoporous silica (AMS)-based epoxy composites with superhydrophobic biomimetic structure surface of Xanthosoma sagittifolium leaves (XSLs) were prepared and applied as anti-corrosion and anti-biofilm coatings. Initially, the AMS was synthesized by the base-catalyzed sol-gel reaction of tetraethoxysilane (TEOS) and triethoxysilane (APTES) through a non-surfactant templating route. Subsequently, a series of AMS-based epoxy composites were prepared by performing the ring-opening polymerization of DGEBA with T-403 in the presence of AMS spheres, followed by characterization through FTIR, TEM, and CA. Furthermore, a nano-casting technique with polydimethylsiloxane (PDMS) as the soft template was utilized to transfer the surface pattern of natural XSLs to AMS-based epoxy composites, leading to the formation of AMS-based epoxy composites with biomimetic structure. From a hydrophilic CA of 69°, the surface of non-biomimetic epoxy significantly increased to 152° upon introducing XSL surface structure to the AMS-based epoxy composites. Based on the standard electrochemical anti-corrosion and anti-biofilm measurements, the superhydrophobic BEAMS3 composite was found to exhibit a remarkable anti-corrosion efficiency of ~99% and antimicrobial efficacy of 82% as compared to that of hydrophilic epoxy coatings.

The Synthesis and Characterization of Selenium-Doped Bioglass.

Background Bioactive glass, which can form strong bonds with tissues, particularly bones, has become pivotal in tissue engineering. Incorporating biologically active ions like selenium enhances its properties for various biomedical applications, including bone repair and cancer treatment. Selenium's antioxidative properties and role in bone health make it a promising addition to biomaterial. Aim The present study was aimed at the preparation and characterization of selenium-doped bioglass. Materials and methods Tetraethyl orthosilicate (TEOS) was mixed with ethanol, water, and nitric acid to form a silica network and then supplemented with calcium nitrate, selenium acid sodium nitrate, and orthophosphoric acid. Sequential addition ensured specific functionalities. After sintering at 300 °C for three hours, the viscous solution transformed into powdered selenium-doped bioglass. Characterization involved scanning electron microscope (SEM) for microstructure analysis, attenuated total reflection infrared spectroscopy (ATR-IR) for molecular structure, and X-ray diffraction (XRD)for crystal structure analysis. Results SEM analysis of selenium-doped bioglass reveals a uniform distribution of selenium dopants in an amorphous structure, enhancing bioactivity through spherical particles with consistent size, micro-porosity, and roughness, facilitating interactions with biological fluids and tissues. ATR-IR analysis shows peaks corresponding to Si-O-Si and P-O bonds, indicating the presence of phosphate groups essential for biomedical applications within the bioglass network. XRD analysis confirms the amorphous nature of selenium-doped bioglass, with shifts in diffraction peaks confirming selenium incorporation without significant crystallization induction. Conclusion The selenium-infused bioglass displays promising versatility due to its amorphous structure, potentially enhancing interactions with biological fluids and tissues. Further research is needed to assess its impact on bone regeneration activity.

Investigation of the Photothermal Performance of the Composite Scaffold Containing Light-Heat-Sensitive Nanomaterial SiO2@Fe3O4

The objective of this investigation was to fabricate a photothermally responsive composite bone scaffold aimed at facilitating bone tissue regeneration and remedying bone defects via mild thermal stimulation. The photothermal-sensitive nanomaterial SiO2 coated Fe3O4 (SiO2@Fe3O4), synthesized through the hydrolysis–condensation process of tetraethyl orthosilicate (TEOS), displayed a uniform distribution of SiO2 coating, effectively preventing the aggregation of Fe3O4 particles within the scaffold matrix. The composite scaffold containing 5% mass fraction of photothermal-sensitive nanoparticles exhibited evenly dispersed microstructural porosity, a compressive strength of 5.722 MPa, and a water contact angle of 58.3°, satisfying the mechanical property requisites of cancellous bone while demonstrating notable hydrophilic characteristics. Upon exposure to near-infrared light at ambient temperature, the 5% composite scaffold underwent a temperature elevation of 3–6 °C within 40–45 s, attaining a temperature range (40–43 °C) conducive to fostering osteogenic differentiation. Experimental findings validated that the SiO2@Fe3O4/polyvinyl alcohol (PVA)/hydroxyapatite (HA)/polycaprolactone (PCL)/β-tricalcium phosphate (β-TCP) bone scaffold showcased outstanding mechanical and photothermal attributes, thereby presenting a pioneering avenue for advancing bone tissue cell proliferation and addressing bone defect rehabilitation.