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1.
Tissue Eng Part C Methods ; 30(6): 268-278, 2024.
Article in English | MEDLINE | ID: mdl-38842184

ABSTRACT

This work employs nitrogen plasma immersion ion implantation (PIII) to modify electrospinning polylactic acid membranes and immobilizes basic fibroblast growth factors (bFGF) by forming crosslinking bonds. The study investigates the modified membranes' surface characteristics and the stimulatory effects of crosslinked bFGF polylactic acid membranes on osteoblast and fibroblast proliferation. The PIII process occurs under low vacuum conditions and is controlled by processing time and power pulse width. The experimental results indicate that, within a 400-second N2-PIII treatment, the spun fibers remain undamaged, demonstrating an increase in hydrophilicity (from 117° to 38°/36°) and nitrogen content (from 0% to 7.54%/8.05%). X-ray photoelectron spectroscopy analysis suggests the formation of a C-N-C=O crosslinked bond. Cell culture and activity assessments indicate that the PIII-treated and crosslinked bFGF film exhibits significantly higher cell growth activity (p < 0.05) than the untreated group. These intergroup differences are attributed to the surface crosslinking bond content. In osteogenic induction, the results for each day show that the treated group performs better. However, the intergroup disparities within the crosslinked bFGF group disappear with prolonged culture time due to the rapid osteogenesis prompted by bFGF. The findings suggest that PIII treatment of electrospinning polylactic acid membranes holds promise in promoting osteogenesis in bone tissue scaffolds.


Subject(s)
Biocompatible Materials , Cell Differentiation , Cell Proliferation , Nanofibers , Osteoblasts , Nanofibers/chemistry , Osteoblasts/cytology , Osteoblasts/drug effects , Osteoblasts/metabolism , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Biocompatible Materials/pharmacology , Biocompatible Materials/chemistry , Animals , Polyesters/chemistry , Polyesters/pharmacology , Fibroblast Growth Factor 2/pharmacology , Fibroblast Growth Factor 2/chemistry , Plasma Gases/pharmacology , Mice , Osteogenesis/drug effects , Lactic Acid/chemistry , Lactic Acid/pharmacology , Photoelectron Spectroscopy
2.
ACS Biomater Sci Eng ; 10(7): 4297-4310, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38900847

ABSTRACT

Interfaces between AISI 304 stainless steel screws and cranial bone were investigated after long-term implantation lasting for 42 years. Samples containing the interface regions were analyzed using state-of-the-art analytical techniques including secondary ion mass, Fourier-transform infrared, Raman, and X-ray photoelectron spectroscopies. Local samples for scanning transmission electron microscopy were cut from the interface regions using the focused ion beam technique. A chemical composition across the interface was recorded in length scales covering micrometric and nanometric resolutions and relevant differences were found between peri-implant and the distant cranial bone, indicating generally younger bone tissue in the peri-implant area. Furthermore, the energy dispersive spectroscopy revealed an 80 nm thick steel surface layer enriched by oxygen suggesting that the AISI 304 material undergoes a corrosion attack. The attack is associated with transport of metallic ions, namely, ferrous and ferric iron, into the bone layer adjacent to the implant. The results comply with an anticipated interplay between released iron ions and osteoclast proliferation. The interplay gives rise to an autocatalytic process in which the iron ions stimulate the osteoclast activity while a formation of fresh bone resorption sites boosts the corrosion process through interactions between acidic osteoclast extracellular compartments and the implant surface. The autocatalytic process thus may account for an accelerated turnover of the peri-implant bone.


Subject(s)
Bone Screws , Skull , Stainless Steel , Bone Screws/adverse effects , Stainless Steel/chemistry , Humans , Corrosion , Skull/pathology , Spectroscopy, Fourier Transform Infrared , Bone-Implant Interface , Surface Properties , Photoelectron Spectroscopy , Spectrum Analysis, Raman , Iron/chemistry
3.
Int J Biol Macromol ; 273(Pt 1): 133096, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38866267

ABSTRACT

Copper ions in wastewater pose a significant threat to human and ecological safety. Therefore, preparing macroscopic adsorbents with reusable and high adsorption performance is paramount. This paper used graphene oxide as the adsorbent and chitosan as the thickener. Additionally, a silane coupling agent was employed to enhance the acid resistance of chitosan, and amino-modification of graphene oxide was performed. Macroscopic adsorbents with high adsorption capacity were fabricated using 3D printing technology. The results show that all five proportions of inks exhibit good printability. Dissolution experiments revealed that all materials maintained structural integrity after 180 days across pH values. Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS) confirmed the successful preparation of the materials. Adsorption experiments showed that the best performing material ratio was 8 wt% graphene oxide and 7 wt% chitosan. Adsorption kinetics and isothermal adsorption experiments demonstrated that the adsorption process occurred via monolayer chemisorption. The adsorption process was attributed to strong electrostatic forces, van der Waals forces, and nitrogen/oxygen-containing functional group coordination. Cycling experiments showed that the material retained good adsorption performance after 6 cycles, suggesting its potential for practical heavy metal treatment applications.


Subject(s)
Chitosan , Copper , Graphite , Chitosan/chemistry , Graphite/chemistry , Copper/chemistry , Adsorption , Kinetics , Hydrogen-Ion Concentration , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Wastewater/chemistry , Cross-Linking Reagents/chemistry , Spectroscopy, Fourier Transform Infrared , Photoelectron Spectroscopy
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124565, 2024 Nov 05.
Article in English | MEDLINE | ID: mdl-38875925

ABSTRACT

Endogenous CO acts as an important messenger for signal transduction and therapeutic effect in the human body. Fluorescent imaging appears to be a promising method for endogenous CO recognition, but traditional luminescent probes based on Pd-complexes suffered from defects of high cost. In this work, four anthracene-derived dyes having an = N-N = group were synthesized for Cu2+-assisted CO sensing. Their molecular structure, photophysical performance and spectral response to Cu2+ and CO were analyzed in detail. The optimal probe showed good selectivity and quenching effect to Cu2+, with PLQY (photoluminescence quantum yield) decreased from 0.33 to 0.04. The quenching mechanism was found as a static quenching mechanism by forming a non-fluorescent complex with Cu2+ (stoichiometric ratio = 1:1), as revealed by single crystal, EPR (electron paramagnetic resonance), and XPS (X-ray photoelectron spectroscopy) analysis. Such quenching effect could be reversed by CO, showing recovered fluorescence, with PLQY recovered to 0.32 within 328 s. Discussion on cellular endogenous CO imaging was included as well.


Subject(s)
Anthracenes , Copper , Fluorescent Dyes , Anthracenes/chemistry , Copper/chemistry , Copper/analysis , Humans , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Spectrometry, Fluorescence , Photoelectron Spectroscopy , Electron Spin Resonance Spectroscopy
5.
Micron ; 184: 103661, 2024 09.
Article in English | MEDLINE | ID: mdl-38833994

ABSTRACT

The silver/magnesium doped hydroxyapatite (AgMgHAp, Ca10-x-yAgxMgy(PO4)6(OH)2, xAg=0.05 and yMg=0.02) nanocomposites coatings were deposited on Si substrate using the dip coating technique. The resulting coatings were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared (FTIR-ATR) spectroscopy, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The EDS analysis highlighted the presence of the constitutive elements of the silver/magnesium doped hydroxyapatite (AgMgHAp) nanocomposites coatings. The surface microtexture of the AgMgHAp was assessed by atomic force microscopy (AFM) technique. The AFM data suggested the obtaining of a uniform deposited layer comprised of equally distributed nanoconglomerates. FT-IR studies highlighted the presence of vibrational modes associated with the phosphate and hydroxyl groups. No bands associated with silver or magnesium were observed. The XPS analysis highlighted the presence of the constituent elements of hydroxyapatite (Ca 2p, P 2 s, O 1 s), as well as dopants (Ag 3d, Mg 1 s and Mg 2p). The antifungal evaluation of AgMgHAp coatings was carried out using the Candida albicans ATCC 10231 fungal strain. The results of the antifungal assay revealed that the AgMgHAp coatings exhibited a strong inhibitory antifungal activity. Furthermore, the data highlighted that the AgMgHAp inhibited the development of biofilm on their surface. The results revealed that the antifungal activity of the coating varied based on the duration of incubation. On the other hand, the data also showed that AgMgHAp nanocomposites coatings inhibited the fungal cell adhesion and development from the early stages of the incubation. In addition to morphological analysis, we additionally take advantage of AFM images to investigate and explore the domain of fractal and multifractal analysis applied to the films under evaluation. Our studies indicates that nanocomposite coatings made from AgMgHAp demonstrate strong antifungal properties. Our studies indicates that nanocomposite coatings made from AgMgHAp demonstrate strong antifungal properties. These results suggest the potential of AgMgHAp nanocomposite coatings as a promising solution for developing innovative antifungal devices in biomedical applications.


Subject(s)
Antifungal Agents , Durapatite , Magnesium , Microscopy, Atomic Force , Nanocomposites , Silver , Durapatite/chemistry , Durapatite/pharmacology , Antifungal Agents/pharmacology , Silver/pharmacology , Silver/chemistry , Nanocomposites/chemistry , Magnesium/chemistry , Magnesium/pharmacology , Spectroscopy, Fourier Transform Infrared , Candida albicans/drug effects , Microscopy, Electron, Scanning , Photoelectron Spectroscopy , Microbial Sensitivity Tests , Spectrometry, X-Ray Emission , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology , Surface Properties
6.
Environ Sci Pollut Res Int ; 31(25): 36643-36662, 2024 May.
Article in English | MEDLINE | ID: mdl-38750274

ABSTRACT

The present research demonstrates an innovative investigation of environmentally friendly mild steel (M-steel) corrosion inhibition using the artemisia stems aqueous extract (ASAEx) as an inhibitor in hydrochloric acid 1 M. The standard extraction technique of hydrodistillation was used for producing the aqueous solutions of ASAEx. To assess the ratios of the chemical components, phytochemical screening was used to identify the stems of this plant. We used a variety of methods and techniques in our research on corrosion inhibition, including weight loss measures, surface analysis methods like XPS and SEM/EDS, electrochemical testing like PDP and EIS, as well as computational lead compound evaluation. Maximum inhibitory efficacy was achieved with 400 mg/L ASAEx in 1 M HCl at 303 K, i.e. 90%. The PDP investigation verified the mixed-kind inhibitor status of the ASAEx extract. To describe the surface of M-steel, fitting and synthetic data were used to identify a constant phase element (CPE). SEM surface analysis was also used to detect the ASAEx effect on the surface of M-steel. X-ray photoelectron spectroscopy (XPS) analysis shows the presence of trace molecules of ASAEx on M-steel surface characterizing the bands in Maj-ASAEx (major compound of ASAEx). Density functional theory (DFT) and molecular dynamics simulations (MDs) were used in computational chemistry to clarify the adsorption mechanism and inhibitory impact.


Subject(s)
Artemisia , Plant Extracts , Steel , Hydrochloric Acid , Plant Extracts/chemistry , Artemisia/chemistry , Plant Stems/chemistry , Steel/chemistry , Photoelectron Spectroscopy
7.
Dent Mater ; 40(6): 921-929, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38719710

ABSTRACT

OBJECTIVES: To investigate the effect of the stability of oxygen vacancies on the low-temperature degradation (LTD) resistance of two kinds of commercial zirconia-based materials (3Y-TZP ceramics and Ce-TZP/Al2O3 composites) via the dielectric probing methods. METHODS: The commercial 3Y-TZP ceramics and Ce-TZP/Al2O3 composites were prepared via conventional solid-state methods. Density, phase content, microstructure, strain, and biaxial flexural strength (BFS) of two materials were investigated using Archimedes method, XRD, SEM, strain-electric field (S-E) loops and ball-on-ring methods, respectively. The concentration of oxygen vacancies before and after LTD of two materials were evaluated using dielectric probing and XPS methods. RESULTS: The XRD analysis revealed that compared to the 3Y-TZP ceramics, the Ce-TZP/Al2O3 composites showed better LTD resistance, without clear LTD. The greater LTD resistance for Ce-TZP/Al2O3 composites was associated with their stability of oxygen vacancies, by higher activation energy based on the dielectric measurements and XPS results. For the 3Y-TZP ceramics that underwent the tetragonal to the monoclinic phase transition during the LTD treatment, the concentration of their oxygen vacancies decreased after LTD. In addition, the Ce-TZP/Al2O3 composites exhibited higher flexural strength and potential fracture toughness based on the BFS testing and strain vs electric field measurement results, indicating a great potential for use in fixed restorative dental applications. SIGNIFICANCE: This work suggested the stability of oxygen vacancies played a key role in the resistance to LTD. Optimizing the stability of the oxygen vacancies is key to the development of more reliable zirconia- based dental biomaterials with greater resistance to LTD.


Subject(s)
Ceramics , Cold Temperature , Flexural Strength , Materials Testing , X-Ray Diffraction , Zirconium , Zirconium/chemistry , Ceramics/chemistry , Yttrium/chemistry , Aluminum Oxide/chemistry , Microscopy, Electron, Scanning , Surface Properties , Photoelectron Spectroscopy , Dental Materials/chemistry , Cerium/chemistry , Dental Stress Analysis , Oxygen/chemistry
8.
J Am Chem Soc ; 146(23): 16062-16075, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38802319

ABSTRACT

Liquid-jet photoemission spectroscopy (LJ-PES) allows for a direct probing of electronic structure in aqueous solutions. We show the applicability of the approach to biomolecules in a complex environment, exploring site-specific information on the interaction of adenosine triphosphate in the aqueous phase (ATP(aq)) with magnesium (Mg2+(aq)), highlighting the synergy brought about by the simultaneous analysis of different regions in the photoelectron spectrum. In particular, we demonstrate intermolecular Coulombic decay (ICD) spectroscopy as a new and powerful addition to the arsenal of techniques for biomolecular structure investigation. We apply LJ-PES assisted by electronic-structure calculations to study ATP(aq) solutions with and without dissolved Mg2+. Valence photoelectron data reveal spectral changes in the phosphate and adenine features of ATP(aq) due to interactions with the divalent cation. Chemical shifts in Mg 2p, Mg 2s, P 2p, and P 2s core-level spectra as a function of the Mg2+/ATP concentration ratio are correlated to the formation of [Mg(ATP) 2]6-(aq), [MgATP]2-(aq), and [Mg2ATP](aq) complexes, demonstrating the element sensitivity of the technique to Mg2+-phosphate interactions. The most direct probe of the intermolecular interactions between ATP(aq) and Mg2+(aq) is delivered by the emerging ICD electrons following ionization of Mg 1s electrons. ICD spectra are shown to sensitively probe ligand exchange in the Mg2+-ATP(aq) coordination environment. In addition, we report and compare P 2s data from ATP(aq) and adenosine mono- and diphosphate (AMP(aq) and ADP(aq), respectively) solutions, probing the electronic structure of the phosphate chain and the local environment of individual phosphate units in ATP(aq). Our results provide a comprehensive view of the electronic structure of ATP(aq) and Mg2+-ATP(aq) complexes relevant to phosphorylation and dephosphorylation reactions that are central to bioenergetics in living organisms.


Subject(s)
Adenosine Triphosphate , Magnesium , Photoelectron Spectroscopy , Magnesium/chemistry , Adenosine Triphosphate/chemistry
9.
ACS Sens ; 9(5): 2395-2401, 2024 05 24.
Article in English | MEDLINE | ID: mdl-38722860

ABSTRACT

PdNi alloy thin films demonstrate exceptional hydrogen sensing performance and exhibit significant potential for application in surface acoustic wave (SAW) hydrogen sensors. However, the long-term stability of SAW H2 sensors utilizing PdNi films as catalysts experiences a substantial decrease during operation. In this paper, X-ray photoelectron spectroscopy (XPS) is employed to investigate the failure mechanisms of PdNi thin films under operational conditions. The XPS analysis reveals that the formation of PdO species on PdNi thin films plays a crucial role in the failure of hydrogen sensing. Additionally, density functional theory (DFT) calculations indicate that hydrogen atoms encounter a diffusion energy barrier during the penetration process from the PdNiOx surface to the subsurface region. The identification of PdNi film failure mechanisms through XPS and DFT offers valuable insights into the development of gas sensors with enhanced long-term stability. Guided by these mechanisms, we propose a method to restore the hydrogen sensing response time and magnitude to a certain extent by reducing the partially oxidized surface of the PdNi alloy under a hydrogen atmosphere at 70 °C, thereby restoring Pd to its metallic state with zero valence.


Subject(s)
Hydrogen , Nickel , Oxidation-Reduction , Palladium , Sound , Hydrogen/chemistry , Palladium/chemistry , Nickel/chemistry , Surface Properties , Density Functional Theory , Photoelectron Spectroscopy , Alloys/chemistry
10.
Waste Manag ; 184: 120-131, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38815286

ABSTRACT

The recycling of spent lithium-ion batteries (LIBs) can not only reduce the potential harm caused by solid waste piles to the local environment but also provide raw materials for manufacturing new batteries. Flotation is an alternative approach to achieve the selective separation of cathode and anode active materials from spent LIBs. However, the presence of organic binder on the surface of hydrophilic lithium transition-metal oxides results in losses of cathode materials in the froth phase. In this study, plasma treatment was utilized to remove organic layers from cathode and anode active materials. Firstly, the correlations between plasma treatment parameters (e.g., input power, air flowrate, and treatment time) were explored and the contact angles of cathode and anode active materials were investigated by the response surface methodology. Secondly, differences in the flotation recoveries of cathode and anode active materials were enhanced with plasma modification prior to flotation, which is consistent with the contact angle measurement. Finally, the plasma-modification mechanisms of hydrophobicity of cathode and anode active materials were discussed according to Fourier Transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses. The proposed method could be a promising tool to enhance the flotation separation efficiency of cathode and anode active materials for the recycling of spent LIBs.


Subject(s)
Electric Power Supplies , Electrodes , Hydrophobic and Hydrophilic Interactions , Lithium , Recycling , Lithium/chemistry , Recycling/methods , Photoelectron Spectroscopy , Spectroscopy, Fourier Transform Infrared , Electronic Waste
11.
Food Chem ; 452: 139556, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-38744133

ABSTRACT

This study explores the molecular interactions and structural changes in κ-carrageenan crosslinked with isovanillin to create a biocomposite material suitable for hard capsule and bio-degradable packaging applications. Proton Nuclear Magnetic Resonance (1H NMR) spectroscopy revealed chemical changes in the conjugate molecule, indicating improved electronegativity due to intermolecular hydrogen bonding between κ-carrageenan and isovanillin. Time-of-flight Secondary Ion Mass Spectrometry (ToF-SIMS) analysis revealed enhanced ion intensity due to intermolecular interactions, particularly between sulphate and hydrogen ions. X-ray Photoelectron Spectroscopy (XPS) study demonstrated that κ-carrageenan and isovanillin form stronger hydrogen bonds, with a shift in binding energy indicating higher electronegativity. These findings shed light on the molecular mechanisms that underpin the formation of the biocomposite material, as well as its potential for use in hard capsule and biodegradable packaging materials, addressing the need for sustainable alternatives in the pharmaceutical and packaging industries while also contributing to environmental conservation.


Subject(s)
Carrageenan , Food Packaging , Magnetic Resonance Spectroscopy , Photoelectron Spectroscopy , Spectrometry, Mass, Secondary Ion , Carrageenan/chemistry , Food Packaging/instrumentation , Hydrogen Bonding , Drug Packaging , Benzaldehydes
12.
Sensors (Basel) ; 24(9)2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38732893

ABSTRACT

An abnormal level of dopamine (DA), a kind of neurotransmitter, correlates with a series of diseases, including Parkinson's disease, Willis-Ekbom disease, attention deficit hyperactivity disorder, and schizophrenia. Hence, it is imperative to achieve a precise, rapid detection method in clinical medicine. In this study, we synthesized nanocomposite carbon aerogels (CAs) doped with iron and iron carbide, based on algae residue-derived biomass materials, using Fe(NO3)3 as the iron source. The modified glassy carbon electrode (GCE) for DA detection, denoted as CAs-Fe/GCE, was prepared through surface modification with this composite material. X-ray photoelectron spectroscopy and X-ray diffraction characterization confirmed the successful doping of iron into the as-prepared CAs. Additionally, the electrochemical behavior of DA on the modified electrode surface was investigated and the results demonstrate that the addition of the CAs-Fe promoted the electron transfer rate, thereby enhancing their sensing performance. The fabricated electrochemical DA biosensor exhibits an accurate detection of DA in the concentration within the range of 0.01~200 µM, with a detection limit of 0.0033 µM. Furthermore, the proposed biosensor is validated in real samples, showing its high applicability for the detection of DA in beverages.


Subject(s)
Biosensing Techniques , Carbon , Dopamine , Electrochemical Techniques , Electrodes , Iron , Biosensing Techniques/methods , Biosensing Techniques/instrumentation , Dopamine/analysis , Dopamine/chemistry , Carbon/chemistry , Iron/chemistry , Electrochemical Techniques/methods , Gels/chemistry , Limit of Detection , Photoelectron Spectroscopy , Nanocomposites/chemistry
13.
Int J Mol Sci ; 25(10)2024 May 07.
Article in English | MEDLINE | ID: mdl-38791107

ABSTRACT

The present study employs X-ray photoelectron spectroscopy (XPS) to analyze plastic samples subjected to degradation processes with the aim to gain insight on the relevant chemical processes and disclose fragmentation mechanisms. Two model plastics, namely polystyrene (PS) and polyethylene (PE), are selected and analyzed before and after artificial UV radiation-triggered weathering, under simulated environmental hydrodynamic conditions, in fresh and marine water for different time intervals. The object of the study is to identify and quantify chemical groups possibly evidencing the occurrence of hydrolysis and oxidation reactions, which are the basis of degradation processes in the environment, determining macroplastic fragmentation. Artificially weathered plastic samples are analyzed also by Raman and FT-IR spectroscopy. Changes in surface chemistry with weathering are revealed by XPS, involving the increase in chemical moieties (hydroxyl, carbonyl, and carboxyl functionalities) which can be correlated with the degradation processes responsible for macroplastic fragmentation. On the other hand, the absence of significant modifications upon plastics weathering evidenced by Raman and FT-IR spectroscopy confirms the importance of investigating plastics surface, which represents the very first part of the materials exposed to degradation agents, thus revealing the power of XPS studies for this purpose. The XPS data on experimentally weathered particles are compared with ones obtained on microplastics collected from real marine environment for investigating the occurring degradation processes.


Subject(s)
Photoelectron Spectroscopy , Plastics , Polyethylene , Photoelectron Spectroscopy/methods , Plastics/chemistry , Polyethylene/chemistry , Spectroscopy, Fourier Transform Infrared/methods , Spectrum Analysis, Raman/methods , Polystyrenes/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/analysis , Seawater/chemistry , Microplastics/chemistry , Oxidation-Reduction
14.
Int J Mol Sci ; 25(9)2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38732121

ABSTRACT

Today a lot of attention is paid to the formation of thermosensitive systems for biomedical and industrial applications. The development of new methods for synthesis of such systems is a dynamically developing direction in chemistry and materials science. In this regard, this paper presents results of the studies of a new synthesized supramolecular polymer system based on polyethylene glycol and tetrafluoroethylene telomers. The films formed from the polymer substance have the property of switching wettability depending on temperature after heating activation. It has been established that the wettability changes at 60 °C. The contact angle of activated hydrophobic polymer film reaches 143°. Additionally, the system exhibits its properties regardless of the pH of the environment. Based on data obtained by the methods of infrared and x-ray photoelectron spectroscopy, differential thermal analysis and thermal analysis in conjunction with wettability and morphology, a model of the behavior of molecules in a polymer system was built that ensures switching of the hydrophilic/hydrophobic surface state. The resulting polymer system, as well as films based on it, can be used in targeted drug delivery, implantation surgery, as sensors, etc.


Subject(s)
Hydrophobic and Hydrophilic Interactions , Polyethylene Glycols , Wettability , Polyethylene Glycols/chemistry , Polymers/chemistry , Temperature , Photoelectron Spectroscopy
15.
J Food Sci ; 89(5): 2747-2760, 2024 May.
Article in English | MEDLINE | ID: mdl-38563096

ABSTRACT

In this study, a new electrochemical sensor based on molybdenum disulfide (MoS2) nanoflowers/glassy carbon electrode (GCE was created for the sensitive detection of gluten. The prepared nanocatalysts were characterized using scanning electron microscopy with energy dispersive spectroscopy, x-ray diffraction, and x-ray photoelectron spectroscopy. The effects of the prepared nanocatalysts, pH value, and dropping amounts on the results were examined in detail. The electrochemical performance of the developed sensor (MoS2 nanoflowers/GCE) was then evaluated using differential pulse voltammetry, and the sensor was found to have significant electrochemical activity against gluten. A substantial linear connection was observed in the range of 0.5-100 ppm of gluten concentration under optimum experimental circumstances, and the detection limit between peak current and gluten concentration was determined as 1.16 ppm. The findings showed that the MoS2 nanoflowers/GCE gluten sensor has exceptional selectivity and stability. Finally, the generated electrochemical sensor was effectively utilized for gluten detection in commercial gluten-containing materials with a detection limit of 0.1652 ppm. Thus, the developed MoS2 nanoflowers/GCE sensor offers a potential method for the detection of other molecules and is a promising candidate for gluten detection in commercial samples.


Subject(s)
Disulfides , Electrochemical Techniques , Enzyme-Linked Immunosorbent Assay , Glutens , Limit of Detection , Molybdenum , Molybdenum/chemistry , Disulfides/chemistry , Glutens/analysis , Electrochemical Techniques/methods , Electrochemical Techniques/instrumentation , Enzyme-Linked Immunosorbent Assay/methods , Electrodes , Nanostructures/chemistry , Food Contamination/analysis , Photoelectron Spectroscopy , X-Ray Diffraction
16.
Int J Biol Macromol ; 267(Pt 2): 131429, 2024 May.
Article in English | MEDLINE | ID: mdl-38583828

ABSTRACT

Herein, a novel chitosan Schiff base (CS-FGA) as a sustainable corrosion inhibitor has been successfully synthesized via a simple amidation reaction by using an imidazolium zwitterion and chitosan (CS). The corrosion inhibition property of CS-FGA for mild steel (MS) in a 1.0 M HCl solution was studied by various electrochemical tests and physical characterization methods. The findings indicate that the maximum inhibition efficiency of CS-FGA as a mixed-type inhibitor for MS in 1.0 M HCl solution with 400 mg L-1 reaches 97.6 %, much much higher than the CS and the recently reported chitosan-based inhibitors. Scanning electron microscopy (SEM), atomic force microscopy (AFM), and water contact angle (WCA) results reveal that the CS-FGA molecules firmly adsorb on the MS surface to form a protective layer. The adsorption of CS-FGA on the MS surface belongs to the Langmuir adsorption isotherm containing both the physisorption and chemisorption. According to the X-ray photoelectron spectroscopy (XPS) and UV-vis spectrum, FeN bonds presented on the MS surface further prove the chemisorption between CS-FGA and Fe to generate the stable protective layer. Additionally, theoretical calculations from quantum chemical calculation (DFT) and molecular simulations (MD) were performed to reveal the inhibition mechanism of CS-FGA.


Subject(s)
Chitosan , Hydrochloric Acid , Steel , Chitosan/chemistry , Steel/chemistry , Corrosion , Hydrochloric Acid/chemistry , Adsorption , Schiff Bases/chemistry , Solutions , Photoelectron Spectroscopy , Surface Properties
17.
J Nanobiotechnology ; 22(1): 88, 2024 Mar 02.
Article in English | MEDLINE | ID: mdl-38431629

ABSTRACT

Functional metal doping endows fluorescent carbon dots with richer physical and chemical properties, greatly expanding their potential in the biomedical field. Nonetheless, fabricating carbon dots with integrated functionality for diagnostic and therapeutic modalities remains challenging. Herein, we develop a simple strategy to prepare Gd/Ru bimetallic doped fluorescent carbon dots (Gd/Ru-CDs) via a one-step microwave-assisted method with Ru(dcbpy)3Cl2, citric acid, polyethyleneimine, and GdCl3 as precursors. Multiple techniques were employed to characterize the morphology and properties of the obtained carbon dots. The Gd/Ru-CDs are high mono-dispersity, uniform spherical nanoparticles with an average diameter of 4.2 nm. Moreover, X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) confirmed the composition and surface properties of the carbon dots. In particular, the successful doping of Gd/Ru enables the carbon dots not only show considerable magnetic resonance imaging (MRI) performance but also obtain better fluorescence (FL) properties, especially in the red emission area. More impressively, it has low cytotoxicity, excellent biocompatibility, and efficient reactive oxygen species (ROS) generation ability, making it an effective imaging-guided tumor treatment reagent. In vivo experiments have revealed that Gd/Ru-CDs can achieve light-induced tumor suppression and non-invasive fluorescence/magnetic resonance bimodal imaging reagents to monitor the treatment process of mouse tumor models. Thus, this simple and efficient carbon dot manufacturing strategy by doping functional metals has expanded avenues for the development and application of multifunctional all-in-one theranostics.


Subject(s)
Carbon , Quantum Dots , Animals , Mice , Carbon/chemistry , Quantum Dots/chemistry , Photoelectron Spectroscopy , Fluorescent Dyes/chemistry , Magnetic Resonance Imaging
18.
PLoS One ; 19(1): e0290761, 2024.
Article in English | MEDLINE | ID: mdl-38215075

ABSTRACT

The rapid, high-resolution material processing offered by ultrashort pulsed lasers enables a wide range of micro and nanomachining applications in a variety of disciplines. Complex laser processing jobs conducted on composite samples, require an awareness of the material type that is interacting with laser both for adjustment of the lasering process and for endpointing. This calls for real-time detection of the materials. Several methods such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-Ray spectroscopy (EDS) can be used for material characterization. However, these methods often need interruption of the machining process to transfer the sample to another instrument for inspection. Such interruption significantly increases the required time and effort for the machining task, acting as a prohibitive factor for many laser machining applications. Laser induced breakdown spectroscopy (LIBS) is a powerful technique that can be used for material characterization, by analyzing a signal that is generated upon the interaction of laser with matter, and thus, it can be considered as a strong candidate for developing an in-situ characterization method. In this work, we propose a method that uses LIBS in a feedback loop system for real time detection and decision making for adjustment of the lasering process on-the-fly. Further, use of LIBS for automated material segmentation, in the 3D image resulting from consecutive lasering and imaging steps, is showcased.


Subject(s)
Lasers , Light , Spectrometry, X-Ray Emission , Photoelectron Spectroscopy
19.
Colloids Surf B Biointerfaces ; 234: 113763, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38262106

ABSTRACT

In the present study, the vanadium pentoxide (V2O5) nickel-doped vanadium pentoxide (Ni@V2O5) was prepared and determined for in vitro anticancer activity. The structural characterization of the prepared V2O5 and Ni@V2O5 was determined using diverse morphological and spectroscopic analyses. The DRS-UV analysis displayed the absorbance at 215 nm for V2O5 and 331 nm for Ni@V2O5 as the primary validation of the synthesis of V2O5 and Ni@V2O5. The EDS spectra exhibited the presence of 30% of O, 69% of V, and 1% of Ni and the EDS mapping showed the constant dispersion. The FE-SEM and FE-TEM analysis showed the V2O5 nanoparticles are rectangle-shaped and nanocomposites have excellent interfaces between nickel and V2O5. The X-ray photoelectron spectroscopy (XPS) investigation of Ni@V2O5 nanocomposite endorses the occurrence of elements V, O, and Ni. The in vitro MTT assay clearly showed that the V2O5 and Ni@V2O5 have significantly inhibited the proliferation of B16F10 skin cancer cells. In addition, the nanocomposite produces the endogenous reactive oxygen species in the mitochondria, causes the mitochondrial membrane and nuclear damage, and consequently induces apoptosis by caspase 9/3 enzymatic activity in skin cancer cells. Also, the western blot analysis showed that the nanocomposite suppresses the oncogenic marker proteins such as PI3K, Akt, and mTOR in the skin cancer cells. Together, the results showed that Ni@V2O5 can be used as an auspicious anticancer agent against skin cancer.


Subject(s)
Nanocomposites , Skin Neoplasms , Vanadium Compounds , Humans , Phosphatidylinositol 3-Kinases , Nickel/pharmacology , Proto-Oncogene Proteins c-akt , Signal Transduction , TOR Serine-Threonine Kinases , Photoelectron Spectroscopy , Apoptosis , Skin Neoplasms/drug therapy
20.
Chemistry ; 30(18): e202303012, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38266207

ABSTRACT

The use of Mg-based biomaterials with a number of their advantageous properties are overshadowed by uncontrollable metal corrosion. Moreover, the use of implants goes alongside with the threat of pathogens-associated complications. In this study, PEO coated Mg biomaterial loaded with antibacterial Ag(I) and Cu(II) complexes is produced and tested to meet both appropriate protective characteristics as well as sufficient level of antibacterial activity. To achieve a suitable level of anticorrosion protection phosphate and fluoride-phosphate electrolytes are used in the PEO process. Investigation of the surface thickness and morphology done by means of cross-section analysis and scanning electron microscopy (SEM), as well as electrochemical impedance spectroscopy (EIS) assay show precedence of the fluoride containing PEO coating and make it the material of choice for further modification with Ag(I) and Cu(II) complexes. The presence of the complexes on the PEO surface is confirmed by energy dispersive X-ray spectroscopy (EDX). X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and glow discharge optical emission spectroscopy (GDOES) are used to estimate the complexes' chemical state and depth of penetration in the coating surface. Based on the results of antibacterial assay, the modified coatings are found to be active against both Gram-positive and Gram-negative bacteria.


Subject(s)
Anti-Bacterial Agents , Fluorides , Anti-Bacterial Agents/pharmacology , Surface Properties , Gram-Negative Bacteria , Gram-Positive Bacteria , Biocompatible Materials , Photoelectron Spectroscopy , Phosphates
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