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This study investigates the characterization and performance of self-cleaning TiO2 surfaces synthesized through a one-step preparation process, followed by enhancement via plasma treatment. The process involved coating aluminum foil with an acrylic paint mixture containing nanoparticles of different mass compositions and subsequent plasma treatment using a continuous plasma arc. Scanning electron microscopy revealed the morphology of the treated surfaces, showing an increase in surface area of plasma-treated materials. Energy-dispersive X-ray spectroscopy revealed changes in oxygen and titanium in acrylic paint/TiO2 surfaces as the TiO2 content increased, indicating successful TiO2 incorporation. Raman spectroscopy showed that the bulk structure of self-cleaning acrylic paints is mainly preserved after plasma treatment. Alternating current impedance spectroscopy assessed that plasma treatment reduced agglomeration and increased active sites, especially for the acrylic paint/TiO2 surfaces with 0.5 mg/cm3 TiO2. The contact angle measurements indicated that plasma treatment enhanced the superhydrophobic characteristics and potential self-cleaning abilities of produced acrylic paint/TiO2 surfaces. The efficacy of these plasma-treated surfaces in self-cleaning was evaluated by testing their performance against puddle sediment and automotive oil samples. The study demonstrated that plasma treatment positively impacted the self-cleaning ability of the acrylic paint/TiO2 surfaces, particularly those with 0.5 mg/cm3 TiO2. This enhancement was attributed to the formation of functional groups, improved water repellency, and possible increases in surface area, which collectively contribute to the sustainable self-cleaning properties of the treated surfaces. [ABSTRACT FROM AUTHOR]

In this study, Cu-doped TiO2 combined with natural zeolite (ZT) was synthesized and applied as a fixed powder layer on poly(methyl methacrylate) (PMMA) tablets. The material's morphology, structural, and chemical properties were characterized using high-resolution scanning electron microscopy, Raman spectroscopy, and Brunauer–Emmett–Teller analysis. The antioxidant capacity was evaluated by assessing the neutralization of hydroxyl radicals and iron (III) ions. For the first time, tablets with Cu-TiO2 and ZT deposited on PMMA as the carrier were investigated for removing two dyes, methyl orange (MO) and methylene blue (MB), from water under simulated solar (SS) and UVC irradiation. Under SS irradiation, the Cu-TiO2/PMMA and Cu-TiO2/ZT/PMMA tablets achieved about 21% degradation of MB after 240 min. This result is particularly noteworthy because SS radiation provides lower energy compared with UVC, making the process more economically efficient. Furthermore, the photocatalysts are immobilized on a stable carrier, which enhances the method's cost-effectiveness by reducing material loss and simplifying recovery. In the presence of ZT/PMMA tablets, 69% of MB was removed by adsorption after 240 min. Additionally, we explored the mechanism of degradation, revealing that the enhanced generation of hydroxyl radicals plays a pivotal role in the effective degradation of MB. At the same time, photogenerated holes contribute to the removal of MO. The overall results suggest that the tablets obtained are a promising solution for water purification due to their effectiveness, simplicity, and low processing cost. [ABSTRACT FROM AUTHOR]

Sunscreen molecules play a critical role in protecting skin from ultraviolet radiation, yet their efficient detection and separation pose challenges in environmental and analytical contexts. In this work, we employ a multilevel modeling approach to investigate the molecular interactions between representative sunscreen molecules and the polydimethylsiloxane (PDMS) polymer, a material widely recognized for its sorbent properties. Our goal is to explore how these interactions can be fine-tuned to facilitate the effective separation of sunscreen molecules in portable membrane inlet mass spectrometry (MIMS) systems, potentially leading to the development of new membrane materials. Using a combination of advanced computational techniques—force field molecular dynamics simulations, semiempirical GFN2-xTB, and density functional theory calculations—we assess the interaction strength and noncovalent interactions of sunscreen molecules, namely oxybenzone, naphthalene, benzo[a]anthracene, avobenzone, and 1,3,5-trichlorobenzene, with PDMS. Additionally, the effect of temperature on the interaction dynamics is evaluated, with the aim of extending the sorbent capacities of PDMS beyond light polar molecules to larger, polar sunscreen compounds. This study provides critical insights into the molecular-level interactions that may guide the design of novel membrane materials for efficient molecular separation. [ABSTRACT FROM AUTHOR]

In this study, we developed TiO2-coated aluminum (TiO2/Al) surfaces using eco-friendly methods to create efficient and environmentally friendly photoactive materials with the potential to enhance water purification systems. TiO2 particles were deposited onto aluminum foil surfaces via a spray method, followed by heat treatment at 200 °C for 15 min. The morphology of the TiO2/Al surfaces, both before and after photocatalytic treatment, was characterized using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The photocatalytic properties of these modified surfaces were evaluated through the degradation of rhodamine B (RB), methylene blue (MB), and methyl orange (MO) under simulated solar and UV–LED irradiation. Among the dyes tested, MO exhibited the highest degradation, influenced by factors such as absorption maximum, molecular structure, charge, and the number of condensed rings. The computational study of interactions between dye molecules and the combined nanoparticle revealed that the binding was the strongest in the case of MO dye. This study also explored the influence of varying the number of TiO2/Al surfaces in solution (one, five, and ten) on the photodegradation efficiency. The solution with five TiO2/Al surfaces demonstrated optimal performance, achieving a 16% degradation of RB. The reusability of the TiO2/Al surfaces was confirmed through five successive runs of RB degradation. The results indicate that TiO2/Al surfaces are a promising solution for addressing water contamination challenges and advancing sustainable water treatment practices. [ABSTRACT FROM AUTHOR]

Bee alarm pheromones are essential molecules that are present in beehives when some threats occur in the bee population. In this work, we have applied multilevel modeling techniques to understand molecular interactions between representative bee alarm pheromones and polymers such as polymethyl siloxane (PDMS), polyethylene glycol (PEG), and their blend. This study aimed to check how these interactions can be manipulated to enable efficient separation of bee alarm pheromones in portable membrane inlet mass spectrometric (MIMS) systems using new membranes. The study involved the application of powerful computational atomistic methods based on a combination of modern semiempirical (GFN2-xTB), first principles (DFT), and force-field calculations. As a fundamental work material for the separation of molecules, we considered the PDMS polymer, a well-known sorbent material known to be applicable for light polar molecules. To improve its applicability as a sorbent material for heavier polar molecules, we considered two main factors—temperature and the addition of PEG polymer. Additional insights into molecular interactions were obtained by studying intrinsic reactive properties and noncovalent interactions between bee alarm pheromones and PDMS and PEG polymer chains. [ABSTRACT FROM AUTHOR]

This comprehensive review covers recent advancements in utilizing various types of polymers and their modifications as photocatalysts for the removal of pharmaceutical contaminants from water. It also considers polymers that enhance the photocatalytic properties of other materials, highlighting their dual role in improving water purification efficiency. Over the past decades, significant progress has been made in understanding the photocatalytic properties of polymers, including organic, inorganic, and composite materials, and their efficacy in degrading pharmaceuticals. Some of the most commonly used polymers, such as polyaniline, poly(p-phenylene vinylene), polyethylene oxide, and polypyrole, and their properties have been reviewed in detail. Physical modification techniques (mechanical blending and extrusion processing) and chemical modification techniques (nanocomposite formation, plasma modification techniques, surface functionalization, and cross-linking) have been discussed as appropriate for modifying polymers in order to increase their photocatalytic activity. This review examines the latest research findings, including the development of novel polymer-based photocatalysts and their application in the removal of pharmaceutical compounds, as well as optimization strategies for enhancing their performance. Additionally, challenges and future directions in this field are discussed to guide further research efforts. [ABSTRACT FROM AUTHOR]

The study comprehensively investigates the design and performance of self-cleaning surfaces fabricated by coating aluminum foil with an acrylic paint matrix enriched with different content of titanium dioxide (TiO2) nanoparticles. The main goal was to assess the self-cleaning characteristics of the surfaces obtained. This study employs scanning electron microscopy (SEM) to analyze the morphology of TiO2-modified acrylic surfaces, revealing spherical particles. Raman spectroscopy elucidates signatures characterizing TiO2 incorporation within the acrylic matrix, providing comprehensive insights into structural and compositional changes for advanced surface engineering. Alternating current (AC) impedance spectroscopy was used to assess selected charge transport properties of produced self-cleaning surfaces, allowing us to gain valuable insights into the material's conductivity and its potential impact on photocatalytic performance. The self-cleaning properties of these tiles were tested against three frequently used textile dyes, which are considered to pose a serious environmental threat. Subsequently, improving self-cleaning properties was achieved by plasma treatment, utilizing a continuous plasma arc. The plasma treatment led to enhanced charge separation and surface reactivity, crucial factors in the self-cleaning mechanism. To deepen our comprehension of the reactive properties of dye molecules and their degradation dynamics, we employed a combination of density functional tight binding (DFTB) and density functional theory (DFT) calculations. This investigation lays the foundation for advancing self-cleaning materials with extensive applications, from architectural coatings to environmental remediation technologies. [ABSTRACT FROM AUTHOR]

Due to the inability of conventional wastewater treatment procedures to remove organic pharmaceutical pollutants, active pharmaceutical components remain in wastewater and even reach tap water. In terms of pharmaceutical pollutants, the scientific community focuses on β-blockers due to their extensive (over)usage and moderately high solubility. In this study, the photocatalytic activity of V2O5 was investigated through the degradation of nadolol (NAD), pindolol (PIN), metoprolol (MET), and their mixture under ultraviolet (UV) irradiation in water. For the preparation of V2O5, facile hydrothermal synthesis was used. The structural, morphological, and surface properties and purity of synthesized V2O5 powder were investigated by scanning electron microscopy (SEM), X-ray, and Raman spectroscopy. SEM micrographs showed hexagonal-shaped platelets with well-defined morphology of materials with diameters in the range of 10–65 µm and thickness of around a few microns. X-ray diffraction identified only one crystalline phase in the sample. The Raman scattering measurements taken on the catalyst confirmed the result of XRPD. Degradation kinetics were monitored by ultra-fast liquid chromatography with diode array detection. The results showed that in individual solutions, photocatalytic degradation of MET and NAD was relatively insignificant (<10%). However, in the PIN case, the degradation was significant (64%). In the mixture, the photodegradation efficiency of MET and NAD slightly increased (15% and 13%). Conversely, it reduced the PIN to the still satisfactory value of 40%. Computational analysis based on molecular and periodic density functional theory calculations was used to complement our experimental findings. Calculations of the average local ionization energy indicate that the PIN is the most reactive of all three considered molecules in terms of removing an electron from it. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2), one of the most frequently used materials in general, has emerged as an excellent photocatalytic material for environmental applications. In this review, principles and mechanisms of the photocatalytic activity of TiO2 have been analyzed. Structural and physical specificities of TiO2 nanoparticles, such as morphology, crystal structure, and electronic and optical properties, have been considered in the context of photocatalytic applications. A review of the influence of several factors, such as the type and dimensions of photocatalyst particles, pH of the solution, the influence of oxidants/electron acceptors, and light intensity on photocatalytic properties of TiO2, has been provided. Superhydrophilicity as an intrinsic property of the TiO2 surface was discussed through surface reconstruction on TiO2 during the reversible hydrophilic changes. Additionally, attention was paid to improving the photocatalytic properties of TiO2 particles through aggregation and agglomeration. [ABSTRACT FROM AUTHOR]

The emerging interest in the field of coordination chemistry and their biological applications has created a novel impact in the field of chemical biology. With this motivation, in this work we have synthesized a novel benzimidazole derived imine ligand, 2-((E)-((1H-benzo[d]-2-yl)methylimino)methyl)-4-fluorophenol (HBMF) and its Co(III) and Cu(II) complexes. The metal complexes (C1–C4) were synthesized in 2:1 (HBMF: metal ion) and 1:1:1 (HBMF: metal ion: 1,10-phen) ratios. Structural elucidations of all the synthesized compounds were performed using FT-IR, UV-Visible, NMR, Mass spectroscopy and elemental analysis techniques. A combination of first principles calculations and molecular dynamics simulations was applied to computationally investigate the structural, reactive, and spectroscopic properties of the newly synthesized HBMF ligand and its complexes with copper and cobalt metal ions. Quantum-mechanical calculations in this study were based on the density functional theory (DFT), while molecular dynamics (MD) simulations were based on the OPLS4 force field. The DFT calculations were used to obtain the reactive and spectroscopic properties of the ligand and its complexes, while molecular dynamics (MD) simulations were used to address the ligand's reactivity with water. Further, the in vitro anti-proliferative activity of the compounds was tested against the A549, Ehrlich–Lettre ascites carcinoma (EAC), SIHA and NIH3T3 cell lines. The biological results depicted that the compound C4, with molecular formula C27H23Cl2CoFN5O3 exhibited profound anti-proliferative activity against the EAC cell line with a significant IC50 value of 10 µm when compared to its parent ligand and other remaining metal complexes under study. Various assays of hematological parameters (alkaline phosphate, creatinine, urea, RBC and WBC) were performed, and significant results were obtained from the experiments. Furthermore, the effect of C4 on neovascularization was evaluated by stimulating the angiogenesis with rVEGF165, which was compared with non-tumor models. The EAC cells were cultured in vivo and administrated with 50 and 75 mg/kg of two doses and tumor parameters were evaluated. [ABSTRACT FROM AUTHOR]

Water pollution is a significant issue nowadays. Among the many different technologies for water purification, photocatalysis is a very promising and environment-friendly approach. In this study, the photocatalytic activity of Sr0.9La0.1TiO3 (SLTO) and Sr0.25Ca0.25Na0.25Pr0.25TiO3 (SCNPTO) nano-sized powders were evaluated by degradation of pindolol in water. Pindolol is almost entirely insoluble in water due to its lipophilic properties. The synthesis of the SCNPTO was performed using the reverse co-precipitation method using nitrate precursors, whereas the SLTO was produced by spray pyrolysis (CerPoTech, Trondheim Norway). The phase purity of the synthesized powders was validated by XRD, while HR-SEM revealed particle sizes between 50 and 70 nm. The obtained SLTO and SCNPTO powders were agglomerated but had relatively similar specific surface areas of about 27.6 m2 g−1 and 34.0 m2 g−1, respectively. The energy band gaps of the SCNPTO and SLTO were calculated (DFT) to be about 2.69 eV and 3.05 eV, respectively. The photocatalytic performances of the materials were examined by removing the pindolol from the polluted water under simulated solar irradiation (SSI), UV-LED irradiation, and UV irradiation. Ultra-fast liquid chromatography was used to monitor the kinetics of the pindolol degradation with diode array detection (UFLC–DAD). The SLTO removed 68%, 94%, and 100% of the pindolol after 240 min under SSI, UV-LED, and UV irradiation, respectively. A similar but slightly lower photocatalytic activity was obtained with the SCNPTO under identical conditions, resulting in 65%, 84%, and 93% degradation of the pindolol, respectively. Chemical oxygen demand measurements showed high mineralization of the investigated mixtures under UV-LED and UV irradiation. [ABSTRACT FROM AUTHOR]

This study investigated the potential of zeolites (NH4BETA, NH4ZSM-5, and NaY) to remove two frequently used dyes, methylene blue (MB) and rhodamine B (RB), from an aqueous environment. The removal of dyes with zeolites was performed via two mechanisms: adsorption and photocatalysis. Removal of dyes through adsorption was achieved by studying the Freundlich adsorption isotherms, while photocatalytic removal of dyes was performed under UV irradiation. In both cases, the removal experiments were conducted for 180 min at two temperatures (283 K and 293 K), and dye concentrations were determined spectrophotometrically. Additionally, after photodegradation, mineralization was analyzed as chemical oxygen demand. A computational analysis of the structures of MB and RB was performed to gain a deeper understanding of the obtained results. The computational analysis encompassed density functional theory (DFT) calculations and analysis of two quantum-molecular descriptors addressing the local reactivity of molecules. Experimental results have indicated that the considered zeolites effectively remove both dyes through both mechanisms, especially NH4BETA and NH4ZSM-5, due to the presence of active acidic centers on the outer and inner surfaces of the zeolite. The lowest efficiency of dye removal was achieved in the presence of NaY zeolite, which has a lower SiO2/Al2O3 ratio. A more efficient reduction was completed for RB dye, which agrees with the computationally obtained information about reactivity. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotubes (SWCNTs) are well-known for their excellent electrical conductivity. One promising application for SWCNT-based thin films is as transparent electrodes for uncooled mid-IR detectors (MIR). In this paper, a combination of computational and experimental studies were performed to understand the chemistry behind the stability of carboxylic SWCNTs (SWCNTs-COOH) dispersions in different solvents. A computational study based on the density functional tight-binding (DFTB) method was applied to understand the interactions of COOH-functionalized carbon nanotubes with selected solvents. Attention was focused on understanding how the protonation of COOH groups influences the binding energies between SWCNTs and different solvents. Thin film electrodes were prepared by alternately depositing PEI and SWCNT-COOH on soda lime glass substrates. To prepare a stable SWCNT dispersion, different solvents were tested, such as deionized (DI) water, ethanol and acetone. The SWCNT-COOH dispersion stability was tested in different solvents. Samples were prepared to study the relationship between the number of depositions, transparency in the MIR range (2.5–5 µm) and conductivity, looking for the optimal thickness that would satisfy the application. The MIR transparency of the electrode was reduced by 20% for the thickest SWCNT layers, whereas sheet resistance values were reduced to 150–200 kΩ/sq. [ABSTRACT FROM AUTHOR]

Highly functionalized spirocyclic ketals were synthesized through asymmetric oxidative spirocyclization via carbanion-induced ring transformation of 2H-pyran-2-ones with 1,4-cyclohexandione monoethyleneketal under alkaline conditions. Further acidic-hydrolysis of obtained spirocyclic ketals yields highly substituted 2-tetralone in good yield. Computational analysis based on the DFT calculations and MD simulations has been performed in order to predict and understand global and local reactivity properties of newly synthesized derivatives. DFT calculations covered fundamental reactivity descriptors such as molecular electrostatic potential and average local ionization energies. Nitrogen atom and benzene rings have been recognized as the most important molecular sites from these aspects. Additionally, to predict whether studied compounds are stable towards the autoxidation mechanism, we have also studied the bond dissociation energies for hydrogen abstraction and identified the derivative which might form potentially genotoxic impurities. Interactions with water, including both global and local aspects, have been covered thanks to the MD simulations and calculations of interaction energies with water, counting of formed hydrogen interactions, and radial distribution functions. MD simulations were also used to identify which excipient could be used together with these compounds, and it has been established that the polyvinylpyrrolidone polymer could be highly compatible with these compounds, from the aspect of calculated solubility parameters. [ABSTRACT FROM AUTHOR]

Herein we report the synthesis and structural elucidation of two novel imine-based ligands, 2-(1,10-phenanthrolin-5-yl)imino)methyl)-5-bromophenol (PIB) and N-(1,10-phenanthrolin-5-yl)-1-(thiophen-3-yl)methanimine (PTM) ligands. An in vitro cytotoxicity assay of the synthesized molecules was carried out against breast, cervical, colorectal, and prostate cancer cell lines as well as immortalized human keratinocytes. The observations indicated that both the molecules possesses dose-dependent selective cytotoxicity of cancer cells with no detrimental effect on the normal cell lines. Furthermore, the detailed computational analysis of newly synthetized ligands (PIB and PTM) has been conducted in order to identify their most important parts from the perspective of local reactivity. The IC50 values of PIB treatment on MCF-7, HeLa, HCT-116 and PC-3 were 15.10, 16.25, 17.88, 17.55 and 23.86 micromoles, respectively. Meanwhile, the IC50 values of PTM on MCF-7, HeLa, HCT-116, PC-3 and HaCat were observed to be 14.82, 15.03, 17.88, 17.28 and 21.22 micromoles, respectively. For computational analysis, we have employed the combination of Density Functional Theory (DFT) calculations and MD simulations. DFT calculations provided us with information about structure and reactivity descriptors based on the electron distribution. Surfaces of molecular electrostatic potential (MEP) and averaged local ionization energy (ALIE) indicated the sites within studied molecules that are most reactive. These results indicated the importance of nitrogen atoms and OH group. Additionally, the values of bond dissociation for hydrogen abstraction showed that both molecules, especially the PTM, are stable toward the influence of autoxidation mechanism. On the other side, MD simulations gave us an insight how ligands interact with water molecules. Namely, the radial distribution functions (RDF) indicated that the hydrogen atom of the OH group in the case of the PIB has the most pronounced interactions with water. [ABSTRACT FROM AUTHOR]