Amino modified nanofibers anchored to Prussian blue nanoparticles selectively remove Cs+ from water.

To improve the selective separation performance of silica nanofibers (SiO2 NFs) for cesium ions (Cs+) and overcome the defects of Prussian blue nanoparticles (PB NPs), PB/SiO2-NH2 NFs were prepared to remove Cs+ from water. Among them, 3-aminopropyltriethoxysilane (APTES) underwent an alkylation reaction with SiO2, resulting in the formation of a dense Si-O-Si network structure that decorated the surface of SiO2 NFs. Meanwhile, the amino functional groups in APTES combined with Fe3+ and then reacted with Fe2+ to form PB NPs, which anchored firmly on the aminoated SiO2 NFs surface. In our experiment, the maximum adsorption capacity of PB/SiO2-NH2 NFs was 111.38 mg/g, which was 31.5 mg/g higher than that of SiO2 NFs. At the same time, after the fifth cycle, the removal rate of Cs+ by PB/SiO2-NH2 NFs adsorbent was 75.36% ± 3.69%. In addition, the adsorption isotherms and adsorption kinetics of PB/SiO2-NH2 NFs were combined with the Freundlich model and the quasi-two-stage fitting model, respectively. Further mechanism analysis showed that the bond between PB/SiO2-NH2 NFs and Cs+ was mainly a synergistic action of ion exchange, electrostatic adsorption and membrane separation.

Stent coating containing a charged silane coupling agent that regulates protein adsorption to confer antithrombotic and cell-adhesion properties.

The evolution of endovascular therapies, particularly in the field of intracranial aneurysm treatment, has been truly remarkable and is characterized by the development of various stents. However, ischemic complications related to thrombosis or downstream emboli pose a challenge for the broader clinical application of such stents. Despite advancements in surface modification technologies, an ideal coating that fulfills all the desired requirements, including anti-thrombogenicity and swift endothelialization, has not been available. To address these issues, we investigated a new coating comprising 3-aminopropyltriethoxysilane (APTES) with both anti-thrombogenic and cell-adhesion properties. We assessed the anti-thrombogenic property of the coating using an in vitro blood loop model by evaluating the platelet count and the level of the thrombin-antithrombin (TAT) complex, and investigating thrombus formation on the surface using scanning electron microscopy (SEM). We then assessed endothelial cell adhesion on the metal surfaces. In vitro blood tests revealed that, compared to a bare stent, the coating significantly inhibited platelet reduction and thrombus formation; more human serum albumin spontaneously adhered to the coated surface to block thrombogenic activation in the blood. Cell adhesion tests also indicated a significant increase in the number of cells adhering to the APTES-coated surfaces compared to the numbers adhering to either the bare stent or the stent coated with an anti-fouling phospholipid polymer. Finally, we performed an in vivo safety test by implanting coated stents into the internal thoracic arteries and ascending pharyngeal arteries of minipigs, and subsequently assessing the health status and vessel patency of the arteries by angiography over the course of 1 week. We found that there were no adverse effects on the pigs and the vascular lumens of their vessels were well maintained in the group with APTES-coated stents. Therefore, our new coating exhibited both high anti-thrombogenicity and cell-adhesion properties, which fulfill the requirements of an implantable stent.

Synthesis of aminopropyl triethoxysilane/melamine incorporated superhydrophilic membranes for simultaneous removal of oil, metals, and Salt ions from produced water.

Water treatment has turned out to be more important in most societies due to the expansion of most economies and to advancement of industrialization. Developing efficient materials and technologies for water treatment is of high interest. Thin film nanocomposite membranes are regarded as the most effective membranes available for salts, hydrocarbon, and environmental pollutants removal. These membranes improve productivity while using less energy than conventional asymmetric membranes. Here, the polyvinylidene fluoride (PVDF) membranes have been successfully modified via dip single-step coating by silica-aminopropyl triethoxysilane/trimesic acid/melamine nanocomposite (Si-APTES-TA-MM). The developed membranes were evaluated for separating the emulsified oil/water mixture, the surface wettability of the membrane materials is therefore essential. During the conditioning step, that is when the freshwater was introduced, the prepared membrane reached a flux of about 27.77 L m-2 h-1. However, when the contaminated water was introduced, the flux reached 18 L m-2 h-1, alongside an applied pressure of 400 kPa. Interestingly, during the first 8 h of the filtration test, the membrane showed 90 % rejection for ions including Mg2+, and SO42- and ≈100 % for organic pollutants including pentane, isooctane, toluene, and hexadecane. Also, the membrane showed 98 % rejection for heavy metals including strontium, lead, and cobalt ions. As per the results, the membrane could be recommended as a promising candidate to be used for a mixture of salt ions, hydrocarbons, and mixtures of heavy metals from wastewater.

Engineering Interfacial Integrity with Hydrolytic-Resistant, Self-Reinforcing Dentin Adhesive.

The leading cause of composite restoration failure is secondary caries, and although caries is a multifactorial problem, weak, damage-prone adhesives play a pivotal role in the high susceptibility of composite restorations to secondary caries. Our group has developed synthetic resins that capitalize on free-radical polymerization and sol-gel reactions to provide dental adhesives with enhanced properties. The resins contain γ-methacryloxypropyltrimethoxysilane (MPS) as the Si-based compound. This study investigated the properties of methacrylate-based resins containing methacryloxymethyltrimethoxysilane (MMeS) as a short-chain alternative. The degree of conversion (DC), polymerization kinetics, water sorption, mechanical properties, and leachates of MMeS- and MPS-resins with 55 and 30 wt% BisGMA-crosslinker were determined. The formulations were used as model adhesives, and the adhesive/dentin (a/d) interfaces were analyzed using chemometrics-assisted micro-Raman spectroscopy. The properties of the 55 wt% formulations were comparable. In the 30 wt% BisGMA formulations, the MMeS-resin exhibited faster polymerization, lower DC, reduced leachates, and increased storage and loss moduli, glass transition (Tg), crosslink density, and heterogeneity. The spectroscopic results indicated a comparable spatial distribution of resin, mineralized, and demineralized dentin across the a/d interfaces. The hydrolytically stable experimental short-chain-silane-monomer dental adhesive provides enhanced mechanical properties through autonomous strengthening and offers a promising strategy for the development of restorative dental materials with extended service life.

Influence of 3-chloropropyl) triethoxysilane and pH on the properties of modified guar gum film.

Guar gum (GG) as a polymer biopolymer is widely used in the field of bio-based packaging. However, its poor mechanical properties, barrier properties and high viscosity greatly hinder its use as an effective packaging material. Therefore, this study introduced CPTES to improve the mechanical (16.58-27.39 MPa) and tensile properties (26.80 %-30.67 %). The FTIR and XRD results indicated a strong interaction between the biofilm fractions modified by CPTES, CPTES bound to the hydroxyl groups on GG and formed a dense polysiloxane network through adsorption and grafting. OM and AFM reflect a denser and flatter film structure on the surface of the G30 film, which has the best film formation. Based on this, the pH of the solution was further adjusted to reach an alkaline environment, disrupting the intermolecular binding through electrostatic repulsion. The rheological behavior indicates that the viscosity and viscoelasticity of film solution gradually decrease with the increase in pH. OM and AFM results show that the G30/8 film has the best compact properties, while the nonporous compact film structure further improves the mechanical, barrierand and thermodynamic properties of the film. Accordingly, the findings of this study had a certain value for regulating the low viscoelasticity of GG emulsion and enhancing the stability of film formation.

Effect of E-glass fibers addition on compressive strength, flexural strength, hardness, and solubility of glass ionomer based cement.

BACKGROUND: In dentistry, glass-ionomer cements (GICs) are extensively used for a range of applications. The unique properties of GIC include fluoride ion release and recharge, chemical bonding to the tooth's hard tissues, biocompatibility, a thermal expansion coefficient like that of enamel and dentin, and acceptable aesthetics. Their high solubility and poor mechanical qualities are among their limitations. E-glass fibers are generally utilized to reinforce the polymer matrix and are identified by their higher silica content. OBJECTIVES: The purpose of the study was to assess the impact of adding (10 wt% and 20 wt%) silane-treated E-glass fibers to traditional GIC on its mechanical properties (compressive strength, flexural strength, and surface hardness) and solubility. METHODS: The characterization of the E-glass fiber fillers was achieved by XRF, SEM, and PSD. The specimens were prepared by adding the E-glass fiber fillers to the traditional GIC at 10% and 20% by weight, forming two innovative groups, and compared with the unmodified GIC (control group). The physical properties (film thickness and initial setting time) were examined to confirm operability after mixing. The evaluation of the reinforced GIC was performed by assessing the compressive strength, flexural strength, hardness, and solubility (n = 10 specimens per test). A one-way ANOVA and Tukey tests were performed for statistical analysis (p ≤ 0.05). RESULTS: The traditional GIC showed the least compressive strength, flexural strength, hardness, and highest solubility. While the GIC reinforced with 20 wt% E-glass fibers showed the highest compressive strength, flexural strength, hardness, and least solubility. Meanwhile, GIC reinforced with 10 wt% showed intermediate results (P ≤ 0.05). CONCLUSION: Using 20 wt% E-glass fiber as a filler with the traditional GIC provides a strengthening effect and reduced solubility.

Novel hydrogel pillar array based ratiometric multicolor fluorescence biosensor for visual detection of alkaline phosphatase activity.

Enzyme-induced in-situ fluorescence is crucial for the development of biosensing mechanisms and correlative spectroscopic analysis. Inspired by simple p-aminophenol (AP)-controlled synthesis and the specific catalytic reaction of 4-aminophenyl phosphate (APP) triggered by alkaline phosphatase (ALP), our research proposed a strategy to prepare carbon dots (CDs) as fluorescent signals for ALP detection using AP and 3-aminopropyltrimethoxysilane (APTMS) as the precursors. The further constructed ratiometric fluorescence sensor reduced the detection limit of ALP to 0.075 µU/mL by a significant margin. Considering the need for point-of-care testing (POCT), we chose agarose for the preparation of portable hydrogel sensors so that even untrained personnel can quickly achieve semi-quantitative visual detection of ALP using colorimetric cards. These results demonstrate the practical applicability of ratiometric fluorescence sensing hydrogel pillar arrays, which are important for high-sensitivity, visualization, and portable rapid enzyme activity assays.

Advancing fluorescence imaging: enhanced control of cyanine dye-doped silica nanoparticles.

BACKGROUND: Silica nanoparticles (SNPs) have immense potential in biomedical research, particularly in drug delivery and imaging applications, owing to their stability and minimal interactions with biological entities such as tissues or cells. RESULTS: With synthesized and characterized cyanine-dye-doped fluorescent SNPs (CSNPs) using cyanine 3.5, 5.5, and 7 (Cy3.5, Cy5.5, and Cy7). Through systematic analysis, we discerned variations in the surface charge and fluorescence properties of the nanoparticles contingent on the encapsulated dye-(3-aminopropyl)triethoxysilane conjugate, while their size and shape remained constant. The fluorescence emission spectra exhibited a redshift correlated with increasing dye concentration, which was attributed to cascade energy transfer and self-quenching effects. Additionally, the fluorescence signal intensity showed a linear relationship with the particle concentration, particularly at lower dye equivalents, indicating a robust performance suitable for imaging applications. In vitro assessments revealed negligible cytotoxicity and efficient cellular uptake of the nanoparticles, enabling long-term tracking and imaging. Validation through in vivo imaging in mice underscored the versatility and efficacy of CSNPs, showing single-switching imaging capabilities and linear signal enhancement within subcutaneous tissue environment. CONCLUSIONS: This study provides valuable insights for designing fluorescence imaging and optimizing nanoparticle-based applications in biomedical research, with potential implications for targeted drug delivery and in vivo imaging of tissue structures and organs.

Effect of surface treatment strategies on bond strength of additively and subtractively manufactured hybrid materials for permanent crowns.

OBJECTIVES: The purpose of this study is to evaluate the bond strength of different computer-aided design / computer-aided manufacturing (CAD/CAM) hybrid ceramic materials following different pretreatments. METHODS: A total of 306 CAD/CAM hybrid material specimens were manufactured, n = 102 for each material (VarseoSmile Crownplus [VSCP] by 3D-printing; Vita Enamic [VE] and Grandio Blocs [GB] by milling). Each material was randomly divided into six groups regarding different pretreatment strategies: control, silane, sandblasting (50 µm aluminum oxide particles), sandblasting + silane, etching (9% hydrofluorics acid), etching + silane. Subsequently, surface roughness (Ra) values, surface free energy (SFE) were measured. Each specimen was bonded with a dual-cured adhesive composite. Half of the specimens were subjected to thermocycling (5000 cycles, 5-55 °C). The shear bond strength (SBS) test was performed. Data were analyzed by using a two-way analysis of variance, independent t-test, and Mann-Whitney-U-test (α = 0.05). RESULTS: Material type (p = 0.001), pretreatment strategy (p < 0.001), and the interaction (p < 0.001) all had significant effects on Ra value. However, only etching on VSCP and VE surface increased SFE value significantly. Regarding SBS value, no significant difference was found among the three materials (p = 0.937), while the pretreatment strategy significantly influenced SBS (p < 0.05). Etching on VSCP specimens showed the lowest mean value among all groups, while sandblasting and silane result in higher SBS for all test materials. CONCLUSIONS: The bond strength of CAD/CAM hybrid ceramic materials for milling and 3D-printing was comparable. Sandblasting and silane coupling were suitable for both millable and printable materials, while hydrofluoric etching should not be recommended for CAD/CAM hybrid ceramic materials. CLINICAL RELEVANCE: Since comparable evidence between 3D-printable and millable CAD/CAM dental hybrid materials is scarce, the present study gives clear guidance for pretreatment planning on different materials.

Cell Wall Modification Based on Combination Reagents to Improve Dimensional Stability of Wood with High Efficiency.

Although γ-methacryloxypropyltrimethoxysilane (MPS) was proved to be an effective reagent for improving the dimensional stability of wood, a bottleneck in ASE value (around 50%) existed. The reason was that MPS with low polarity opened few hydrogen bonds in the amorphous region of cellulose, while these hydrogen bonds could be reopened by water. Therefore, citric acid (CA) is chosen to cooperate with MPS to further enhance the dimensional stability of wood. In this paper, MPS and CA were used to modify wood individually (MW and CW) or with different combinations, that is, one-step modification (M/CW) and two-step modification with MPS first (M-CW) or CA first (C-MW). CA and MPS concentrations were optimized at 5 wt%. The ASE value for M/CW was only 25.74% at a weight percent gain (WPG) of 6.43%, which was only 0.6 times to MW or 0.7 times to CW. For M-CW, the ASE value gradually decreased with the soaking cycles, from 65.64% at a WPG of 9.05% to 51.20%. The C-MW had the best dimensional stability, with the ASE value 75.35% at a WPG of 11.50%. Although it decreased during the first soaking cycle, it stabilized at 62.20% at last. SEM and EDS images showed that the polymer mainly distributed in cell walls and few in cell lumen in C-MW. Thus, the enhanced dimensional stability of C-MW could be explained by CA opening the hydrogen bonds in the amorphous region of cellulose first, which provided more binding sites for MPS.

Novel organic-inorganic composite pea protein silica food-grade aerogel materials: Fabrication, mechanisms, high oil-holding property and curcumin delivery capacity.

The fragility of the skeleton and poor bioaccessibility limit Silica aerogel's application in the food industry. In this study, composite gels were obtained by cross-linking pea proteins isolate (PPI) with Tetraethoxysilane (TEOS)to improve the bioavailability of silica-derived aerogels. It indicated that TEOS first condensed with H+ to form secondary particles and then complexed with PPI via hydroxyl groups to form a composite aerogel. Meanwhile, the PPI-Si composite aerogel formed a dense mesoporous structure with a specific surface area of 312.5 g/cm3. This resulted in a higher oil holding percentage of 89.67 % for the PPI (10 %)-Si aerogel, which was 34.1 % higher than other studies, leading to a more stable oleogel. Finally, as a delivery system, the composite oleogel not only could significantly increase the bioaccessibility rate by 27.4 % compared with silica aerogel, but also could efficiently inhibit the premature release of curcumin in the simulated gastric fluids, while allowed sustainably release in the simulated intestinal fluids. These results provided a theoretical basis for the application of silica-derived aerogels in food and non-food applications.

Effect of molecular weight of PEI on the strength and hydrophobic performance of fiber-based papers via PEI-KH560 surface sizing.

In recent years, researchers have put much attention on the improvements and upgrades of novel wet strength agent in the papermaking fields, especially in the usage of household paper. Herein, PEIM-KH560 by polyethyleneimine (PEI) and γ-glycidyl ether propyl trimethoxysilane (KH560) was synthesized with five molecular weights (Mw) of PEI at 600, 1800, 10,000, 70,000 and 750,000. Results showed that the molecular weight greatly influenced the physicochemical properties of PEI-KH560, such as the size and thermal stability. The intrinsic cationic charge of PEI-KH560 provided the bonding sites with the paper fibers, forming strengthened fiber-fiber joints. It was shown that the dry, wet strength and hydrophobicity of cellulosic paper sheets were obviously improved. When the m (PEI):m(KH560) is 1:2, the strength of papers after sizing by Mw of PEI at 600 and 1800 is the most obvious, with the dry strength increased by 227.9 % and 187.5 %, and the wet strength increased by 183.8 % and 207.8 %, respectively. The maximum hydrophobicity was found at the PEI1800-KH560 with the contact angle value of 130.6°. The resultant environmental-friendly agent (PEI-KH560) obtained in this work provides valuable significance for the preparation of household and food packaging paper.

Ionic Liquid-Based Silane for SiO2 Nanoparticles: A Versatile Coupling Agent for Dental Resins.

The current longevity of dental resins intraorally is limited by susceptibility to acidic attacks from bacterial metabolic byproducts and vulnerability to enzymatic or hydrolytic degradation. Here, we demonstrate synthesizing an ionic liquid-based antibiofilm silane effective against Streptococcus mutans, a major caries pathogen. Furthermore, we incorporate this silane into dental resins, creating antibiofilm- and degradation-resistant materials applicable across resin types. FTIR, UV-vis, and NMR spectroscopy confirmed the synthesis of the expected ionic liquid-based silane. The characterization of SiO2 after the silanization indicated the presence of the silane and how it interacted with the oxide. All groups achieved a degree of conversion similar to that found for commercial resin composites immediately and after two months of storage in water. The minimum of 2.5 wt % of silane led to lower softening in solvent than the control group (GCTRL) (p < 0.05). While the flexural strength indicated a lower value from 1 wt % of silane compared to GCTRL (p < 0.05), the ultimate tensile strength did not indicate differences among groups (p > 0.05). There was no difference within groups between the immediate and long-term tests of flexural strength (p > 0.05) or ultimate tensile strength (p > 0.05). The addition of at least 5 wt % of silane reduced the viability of S. mutans compared to GCTRL (p < 0.05). The fluorescence microscopy analysis suggested that the higher the silane concentration, the higher the amount of bacteria with membrane defects. There was no difference among groups in the cytotoxicity test (p > 0.05). Therefore, the developed dental resins displayed biocompatibility, proper degree of conversion, improved resistance against softening in solvent, and stability after 6 months of storage in water. This material could be further developed to produce polymeric antimicrobial layers for different surfaces, supporting various potential avenues in developing novel biomaterials with enhanced therapeutic characteristics using ionic liquid-based materials.

Development of an Azobenzene-Based Cell Culture Photoresponsive Platform for In Situ Modulation of Surface Topography in Wet Environments.

Azopolymers are light-responsive materials that hold promise to transform in vitro cell culture systems. Through precise light illumination, they facilitate substrate pattern formation and erasure, allowing for the dynamic control and creation of active interfaces between cells and materials. However, these materials exhibit a tendency to locally detach from the supporting glass in the presence of aqueous solutions, such as cell culture media, due to the formation of blisters, which are liquid-filled cavities generated at the azopolymer film-glass interface. These blisters impede precise structurization of the surface of the azomaterial, limiting their usage for surface photoactivation in the presence of cells. In this study, we present a cost-effective and easily implementable method to improve the azopolymer-glass interface stability through silane functionalization of the glass substrate. This method proved to be efficient in preventing blister formation, thereby enabling the dynamic modulation of the azopolymer surface in situ for live-cell experiments. Furthermore, we proved that the light-illumination conditions used to induce azopolymer surface variations do not induce phototoxic effects. Consequently, this approach facilitates the development of a photoswitchable azopolymer cell culture platform for studying the impact of multiple in situ inscription and erasure cycles on cell functions while maintaining a physiological wet microenvironment.

Silanization Strategies for Tailoring Peptide Functionalization on Silicon Surfaces: Implications for Enhancing Stem Cell Adhesion.

Biomaterial surface engineering and the integration of cell-adhesive ligands are crucial in biological research and biotechnological applications. The interplay between cells and their microenvironment, influenced by chemical and physical cues, impacts cellular behavior. Surface modification of biomaterials profoundly affects cellular responses, especially at the cell-surface interface. This work focuses on enhancing cellular activities through material manipulation, emphasizing silanization for further functionalization with bioactive molecules such as RGD peptides to improve cell adhesion. The grafting of three distinct silanes onto silicon wafers using both spin coating and immersion methods was investigated. This study sheds light on the effects of different alkyl chain lengths and protecting groups on cellular behavior, providing valuable insights into optimizing silane-based self-assembled monolayers (SAMs) before peptide or protein grafting for the first time. Specifically, it challenges the common use of APTES molecules in this context. These findings advance our understanding of surface modification strategies, paving the way for tailoring biomaterial surfaces to modulate the cellular behavior for diverse biotechnological applications.

Synthesis of Zwitterionic Phospholipid-Connected Silane Coupling Agents and Their Hybridization with Graphene Oxide.

The hybridization of lipids with graphene is expected to produce a promising, novel biomaterial. However, there are limited examples of the covalent introduction of lipid molecules, especially the immobilization of lipid molecules, onto graphene on a substrate. Therefore, we investigated the hybridization of a silane coupling agent having phospholipid moieties with graphene oxide on substrates prepared by photo-oxidation using chlorine dioxide. Three silane coupling agents with different carbon chain lengths (C4, C6, C8) were synthesized and phospholipid molecules were introduced onto graphene on a substrate. Phospholipid-immobilized graphene on a grid for TEM (transmission electron microscope) was used for EM analysis of proteins (glyceraldehyde 3-phosphate dehydrogenase and ß-galactosidase), enabling the observation of sufficient particles compared to the conventional graphene grid.

Effects of dentin bonding agents and silanization on bond strength between 3D printed resin and composite resin.

This study aimed to evaluate the effects of dentin bonding agents and silanization on the bond strength between 3D printed resin and composite resin and compare it with a conventional composite resin. 3D printed resin cylinders (PCB) and composite resin substrates (Z250) were prepared and divided into eight subgroups based on the bonding agents used (n=12). The shear bond strength was measured using a universal testing machine, and the failure modes were evaluated. The bond strength was found to vary significantly among the bonding agents and substrate types. Silane application did not significantly improve the bond strength. Among the bonding agents, the universal adhesives exhibited the highest bond strengths for both substrates. Compared to PCB, Z250 demonstrated stronger bonds and exhibited more cohesive failures. Further research is needed to optimize the surface treatments and resin formulations for enhanced bond strength and durability between 3D printed and composite resins.

A Wettability Contrast SERS Droplet Assay for Multiplexed Analyte Detection.

Droplet assay platforms have emerged as a significant methodology, providing distinct advantages such as sample compartmentalization, high throughput, and minimal analyte consumption. However, inherent complexities, especially in multiplexed detection, remain a challenge. We demonstrate a novel strategy to fabricate a plasmonic droplet assay platform (PDAP) for multiplexed analyte detection, enabling surface-enhanced Raman spectroscopy (SERS). PDAP efficiently splits a microliter droplet into submicroliter to nanoliter droplets under gravity-driven flow by wettability contrast between two distinct regions. The desired hydrophobicity and adhesive contrast between the silicone oil-grafted nonadhesive hydrophilic zone with gold nanoparticles is attained through (3-aminopropyl) triethoxysilane (APTES) functionalization of gold nanoparticles (AuNPs) using a scotch-tape mask. The wettability contrast surface facilitates the splitting of aqueous droplets with various surface tensions (ranging from 39.08 to 72 mN/m) into ultralow volumes of nanoliters. The developed PDAP was used for the multiplexed detection of Rhodamine 6G (Rh6G) and Crystal Violet (CV) dyes. The limit of detection for 120 nL droplet using PDAP was found to be 134 pM and 10.1 nM for Rh6G and CV, respectively. These results align with those from previously reported platforms, highlighting the comparable sensitivity of the developed PDAP. We have also demonstrated the competence of PDAP by testing adulterant spiked milk and obtained very good sensitivity. Thus, PDAP has the potential to be used for the multiplexed screening of food adulterants.

Effect of water glass treatment for zirconia and silane coupling on bond strength of resin cement.

OBJECTIVE: To evaluate the ability of the water glass treatment to penetrate zirconia and improve the bond strength of resin cement. MATERIAL AND METHODS: Water glass was applied to zirconia specimens, which were then sintered. The specimens were divided into water-glass-treated and untreated zirconia (control) groups. The surface properties of the water-glass-treated specimens were evaluated using surface roughness and electron probe micro-analyser (EPMA) analysis. A resin cement was used to evaluate the tensile bond strength, with2 and without a silane-containing primer. After 24 h in water storage at 37 °C and thermal cycling, the bond strengths were statistically evaluated with t-test, and the fracture surfaces were observed using SEM. RESULTS: The water glass treatment slightly increased the surface roughness of the zirconia specimens, and the EPMA analysis detected the water glass penetration to be 50 µm below the zirconia surface. The application of primer improved the tensile bond strength in all groups. After 24 h, the water-glass-treated zirconia exhibited a tensile strength of 24.8 ± 5.5 MPa, which was significantly higher than that of the control zirconia (17.6 ± 3.5 MPa) (p < 0.05). After thermal cycling, the water-glass-treated zirconia showed significantly higher tensile strength than the control zirconia. The fracture surface morphology was mainly an adhesive pattern, whereas resin cement residue was occasionally detected on the water-glass-treated zirconia surfaces. CONCLUSION: The water glass treatment resulted in the formation of a stable silica phase on the zirconia surface. This process enabled silane coupling to the zirconia and improved the adhesion of the resin cement.

Sea urchin nanostructured nickel cobaltite modified carbon cloth integrated wearable patches for the on-site detection of the immunosuppressant drug mycophenolate mofetil.

Mycophenolate mofetil (MpM) is a medication used to prevent the rejection of transplanted organs, particularly in kidney, heart, and liver transplant surgeries. It is extremely important to be conscious that MpM can raise the risk of severe infections and some cancers if it exceeds the recommended dose while lower doses will result in organ rejections. So, it is essential to monitor the dosage of MpM in real time in the micromolar range. In this work, we have synthesized 3-aminopropyltriethoxysilane (APTES) functionalized nickel cobaltite (NiCo2O4) and this amino functionalization was chosen to enhance the stability and electrochemical activity of NiCo2O4. The enhanced activity of NiCo2O4 was used for developing an electrochemical sensor for the detection of MpM. APTES functionalized NiCo2O4 was coated on carbon cloth and used as the working electrode. Surface functionalization with APTES on NiCo2O4 was aimed at augmenting the adsorption/interaction of MpM due to its binding properties. The developed sensor showed a very low detection limit of 1.23 nM with linear ranges of 10-100 nM and 1-100 µM and its practical applicability was examined using artificial samples of blood serum and cerebrospinal fluid, validating its potential application in real-life scenarios.