UV Absorption Research Articles

Dynamic impact of different human activities on the distribution of organic ultraviolet absorbers in coastal aquatic environments: A case study in Beibu Gulf, South China Sea

The increasing environmental concern surrounding organic ultraviolet absorbers (OUVAs) has prompted heightened attention, particularly their presence in personal care products (organic ultraviolet filters, OUVFs) and industrial products (organic ultraviolet stabilizers, OUVSs). This study investigates the impact of human activities and environmental factors on the occurrence, spatiotemporal distribution, and ecological risk of eight commonly utilized OUVFs and OUVSs in the coastal region of Beibu Gulf, South China Sea. The study area is characterized by multiple functional zones with distinct human activities. Results reveal elevated concentrations of OUVAs during summer compared to winter, attributed to increased residential usage, tourist activities, industrial releases, and intensified ultraviolet (UV) radiation. Interestingly, the proportion of OUVFs increases during summer, while OUVSs decrease. Correlation analysis between OUVAs and sampling sites reveals that tourism and domestic wastewater are the main contributors to OUVF contamination in summer, whereas mariculture and port trade significantly impact OUVS contamination in winter. The ecological risk assessment indicates predominantly low or medium risk levels for most OUVAs in both local seawater and freshwater ecosystems. Nevertheless, OUVFs, with a particular focus on 4-methylbenzylidene camphor (4-MBC), and OUVSs, specifically 2-(2-hydroxy-5-methylphenyl) benzotriazole (UV-P), exhibit a heightened risk compared to alternative substances. These findings provide crucial insights into the development of targeted mitigation strategies for OUVAs, taking into account the varying contamination levels of OUVFs and OUVSs resulting from diverse human activities, aiming to protect the health of aquatic ecosystems in diverse functional zones.

Potential of silk proteins in cosmetics

Synthetic and inorganic chemical ingredients in cosmetic products pose serious health impacts on skin and hair. Much emphasis has been laid on the development of cost-effective, eco-friendly and user-friendly cosmetic products from time to time. Manufacturing cosmetics using natural ingredients is considered as a viable alternative to overcome the side effects of synthetics. Silk is a natural biopolymer obtained from cocoons of sericigenous insects like silkworms. It constitutes two proteins, viz., fibroin and sericin. Fibroin is the central core protein glued with sericin protein forming silken cocoons together. Both the proteins possess remarkable attributes viz, anti-microbial, anti-oxidant, anti-tyrosinase activity, efficient UV resistance, kinase activity, excellent release and absorption of moisture. The silk protein attributes are advantageous for body skin, hair and nails. It possesses a wide range of cosmetic applications such as facilitation of hair growth, improvement in softening and lustre of hair, rejuvenation of body and skin cells, UVB protection, prevention of chapping and brittleness of nails, and skin brightening. Due to its low molecular weight, easily penetrates the hair strands and skin cells, binds the keratin in hair and forms a protective layer to prevent moisture loss. A wide range of products have been developed for use in cosmetics viz., SILKPRO, SILKALL, SILKPRO 1000. These products are used as natural ingredients due to their potent applications in cosmetics. The cosmetic industry can be developed by proper utilization of silk in its organic products while promoting value addition to sericulture industry.

Structural, electronic, optical, mechanical, and phononic bulk properties of tetragonal trirutile antimonate MSb2O6 (M = Fe, Co, Ni, or Zn): a first-principles prediction for optoelectronic applications

Abstract This work does an extensive analysis of the optoelectronic and mechanical properties of the tri rutile structure type 3d transition metal Antimonate MSb2O6 (M = Fe, Co, Ni, or Zn), for the first time, utilizing the pseudo-potential plane wave approach within the density functional theory framework. When calculating the structural, optical, and mechanical properties, the exchange–correlation interactions were studied using the GGA-PBE functional, whereas when computing electronic, it is analyzed using the HSE06 hybrid functional. The equilibrium lattice parameters exhibit good agreement with the available experimental results. The electronic properties were estimated using the GGA-PBE and HSE06 functionals. Based on the calculated electronic properties with the GGA-PBE functional, the FeSb2O6, CoSb2O6, and NiSb2O6 materials exhibit metallic behavior with energy gap values of 0 eV, while ZnSb2O6 is a semiconductor with a narrow direct band gap (Γ–Γ) of 0.5 eV. Furthermore, the computed band gaps using the HSE06 functional are 0 eV, 0 eV, 1 eV (Γ–Γ), and 4 eV (Γ–Γ) for FeSb2O6, CoSb2O6, NiSb2O6, and ZnSb2O6, respectively. Density of states diagrams were used to gain deeper insights into the characteristics of the energy bands. The optical properties of these compounds, such as the dielectric function, energy loss function, conductivity, reflectivity, refractive index, and absorption coefficient were investigated over the energy range of 0 to 40 eV. The materials exhibited a high absorption coefficient and a significantly low reflectivity within the UV–vis energy spectrum. The negative cohesive energy Ecoh implies the chemical (thermodynamic) stability of the trirutile MSb2O6 (M = Fe, Co, Ni, or Zn). Mechanical stability is confirmed by applying the Born stability criteria using elastic constants (Cij). The absence of imaginary frequencies in the phonon spectrum calculations confirms the dynamic stability of the studied compounds. These results are consistent with previous experimental research on these materials in photocatalysis and gas sensor applications. On the other hand, these compounds possess exceptional high and broad optical absorption UV range, making them suitable for use in next-generation ultraviolet photodetectors.

Computational insights into transition metal-based BaCoX3 (X = Cl, Br, I) halide perovskites for spintronics, photovoltaics, and renewable energy devices

Ab-initio simulations using density functional theory (DFT) were employed to investigate the structural, mechanical, electronic, magnetic, optical, and thermoelectric properties of halide perovskites \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {BaCoX}_3$$\\end{document} (X = Cl, Br, I). Structural optimization and mechanical stability assessments confirm the reliability of these perovskites in a hexagonal P\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$6_3$$\\end{document}mc symmetry. The stability of the ferromagnetic phase was validated through total crystal energy minimization via Murnaghan’s equation of state. Electronic band structures and density of states, derived from the generalized gradient approximation (GGA), reveal a semiconducting ferromagnetic nature in the spin up channel, spotlighting their potential in semiconductor spintronic applications. Phonon dispersion analysis of \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {BaCoCl}_3$$\\end{document} and \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {BaCoBr}_3$$\\end{document} revealed positive phonon modes throughout the entire Brillouin zone, confirming their dynamical stability. In contrast, \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {BaCoI}_3$$\\end{document} demonstrated dynamical instability. The elastic constants confirm the mechanical stability and ductile nature of the perovskites. Optical and dielectric properties of these perovskites show significant UV absorption and photoconductivity, making them highly suitable for optoelectronic and solar cell applications. Finally, transport properties, such as the Seebeck coefficient, electrical conductivity, thermal conductivity, power factor, and figure of merit (ZT) unveil their exceptional thermoelectric performance. Combining half-metallic ferromagnetic traits with superior thermoelectric and optoelectronic performance positions \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {BaCoX}_3$$\\end{document} compounds as exceptional candidates for applications in spintronics, optoelectronics, and thermoelectrics. This comprehensive investigation demonstrates their ability to excel across a diverse array of advanced technological applications.

TiN/TiO2 embedded in ReS2 nanoflowers with wide light absorption and multi-interfacial charge transfer for efficient photocatalytic hydrogen generation

The design of functional materials with efficient light absorption and charge separation is crucial for photocatalytic energy conversion. Herein, a plasmonic TiN/TiO2/ReS2 ternary hybrid is prepared, which exhibits exceptional photocatalytic activity caused by the plasmon-mediated light absorption and multi-interfacial charge separation. The ternary hybrids were synthesized by heating TiN, Re, and S sources at high pressure and temperature. The TiN was partially oxidized to form TiN/TiO2 hybrids, which were then embedded in ReS2 nanoflowers through Ti-S bonds, creating a 3D flower-like structure with multiple interfaces. The plasmon resonance of TiN and the bandgap excitations of ReS2 and TiO2 endow the hybrids with efficient light absorption in UV–VIS-NIR region. Additionally, the novel embedded structure and the multiple interfaces between TiN, TiO2, and ReS2 facilitate the formation of built-in electric fields and multi-channel charge transfer, which efficiently quicken photoinduced carriers’ migration and hot electron injection. Consequently, the TiN/TiO2/ReS2 hybrids demonstrate a high-efficiency photocatalytic hydrogen generation rate, which is 12.1 times that of commercial P25. Notably, the hybrids also exhibit high photocatalytic activity under near-infrared light irradiation. This study offers innovative insights into the design of photocatalysts and suggests that the prepared materials could be utilized in solar-driven energy conversion applications.

Synthesis and Characterization of Chitosan–Silver Nanocomposite Film: Antibacterial and Cytotoxicity Study

AbstractThis study is aimed at the in situ preparation and antibacterial study of silver nanoparticles within the matrix of an eco‐friendly, biocompatible, biodegradable, and bioavailable biopolymer (chitosan) to form Chi–AgNP film via multiple noncovalent interactions between the organic polymer and the nanoparticles. The film is fully characterized by infrared and ultraviolet spectroscopy, scanning electron microscopy, transmission electron microscopy, X‐ray photoelectron spectroscopy, and thermogravimetric analysis. The characterization confirms the successful incorporation of silver nanoparticles into the polymeric network. Infrared spectroscopy reveals peaks corresponding to the vibration of functional groups present in chitosan with enhanced intensity and blueshifts caused by the presence of silver nanoparticles. Well‐monodispersed spherical silver nanoparticles with an average size of 10 nm are observed in the Chi–AgNP film. The surface plasmon resonance at 447 nm is consistent with a typical silver plasmon. Furthermore, the antibacterial effects on E. coli and S. aureus were determined and attributed to the release of AgNPs observed by UV absorption.

Improving UV protection and retention of photosensitive agrochemicals: Innovative polyurethane-CeO2 hybrid pesticide microcapsules

Photolysis and poor retention significantly decrease the utilization efficiency of photosensitive agrochemicals, leading to considerable ecological and economic losses. We successfully prepared novel pyraclostrobin-loaded polyurethane-inorganic hybrid microcapsules (Pyr@KCeO2-PU MCs) with high adhesion and UV stability by interfacial polymerization. CeO2 nanoparticles (NPs) were incorporated as UV light absorbers, while a silane coupling agent (KH550) was employed for in situ crosslinking of PU with CeO2 NPs, facilitating their dispersion within the PU shell. Characterization results revealed a high encapsulation efficiency of 90 % and uniform sizes (D50 = 915 nm) for the Pyr@KCeO2-PU MCs. Optical property investigations using UV–vis spectroscopy indicated that the integration of CeO2 NPs within the PU shell produced stronger UV absorption bands compared to both Pyr technical (TC) and Pyr@PU MCs. This observation underscores the potential of CeO2 NPs as effective UV absorbers. The anti-photolysis performance of Pyr@KCeO2-PU MCs improved with the addition of CeO2 NPs, yielding a retention rate of Pyr in Pyr@KCeO2-PU MCs that was 1.90 and 1.27 times greater than that of Pyr TC and Pyr@PU MCs, respectively, under UV irradiation. Furthermore, KH550 not only facilitated crosslinking between PU and CeO2 NPs, ensuring uniform distribution of CeO2 NPs on the PU shell surface, but also enhanced wettability and foliar retention. The contact angle of Pyr@KCeO2-PU MCs (32°) was significantly lower than that of Pyr@PU MCs (84°), and Pyr retention on rice leaves was 17.5 mg/cm2 for Pyr@KCeO2-PU MCs, surpassing that of Pyr@PU MCs (9.3 mg/cm2). Additionally, Pyr@KCeO2-PU MCs exhibited superior efficacy against various plant pathogens compared to Pyr TC and Seltima. These findings highlight the potential of Pyr@KCeO2-PU MCs for enhancing pesticide utilization and offer valuable insights for the future development of PU-based pesticide formulations.

Synergistic sun protection via glucosylrutin-enhanced multiple emulsions

A sunscreen multiple emulsion with a “two films and three phases” structure was prepared using a two-step emulsification method. In this system, the inner aqueous phase contained dissolved Glucosylrutin, while the oil phase included a triazine-based chemical UV absorber. The composition and morphology of the emulsion were optimized, and its rheological properties and physical stability were analyzed. This study demonstrates the application of multiple emulsions in sun protection, highlighting their synergistic behavior in UV defense and their capacity to enhance the antioxidant properties derived from Glucosylrutin.

Interfacial structure modification and enhanced emulsification stability of microalgae protein through interaction with anionic polysaccharides

Microalgae protein (MP) have emerged as a focal point of research within food processing due to its nutritional value and foaming properties. However, its isoelectric point around pH 4 leads to it susceptible to collision, binding, and precipitation. Additionally, MP has poor emulsification properties and only shows stability under strongly alkaline conditions. This study investigated the effects of food-grade anionic polysaccharides (guar gum (GG), gum arabic (GA), low acyl gellan gum (LG), and pectin (PT)) on the molecular structure and emulsification properties of MP. Results indicated that these anionic polysaccharides enhanced the UV absorption of MP near 620 nm, especially at 14 % content, while fluorescence intensity decreased due to amino acid residues masking without structural changes. The addition of polysaccharides resulted in bimodal or multimodal particle size distributions, with LG and PT showing larger particle sizes. At pH 4, negatively charged polysaccharides formed stable complexes with near-neutral MP, improving solution stability via electrostatic repulsion and diminishing turbidity. The droplet distribution analysis indicated that higher anionic polysaccharide ratios (1:4, 1:2, and 1:1) correlated with smaller droplet sizes and increased emulsion stability. Zeta-potential measurements revealed negative charges for emulsions, with LG-MP and PT-MP complexes displaying higher absolute values (15.0 to 20.7 mV) compared to GG-MP and GA-MP complexes, indicating superior stability. Storage stability analysis showed that LG-MP and PT-MP complexes stabilized emulsions had minimal delamination over two weeks. Rheological assessments showed that increasing GG and GA contents from 14 % to 50 % had negligible effects on apparent viscosity, while LG-MP (1:1) complexes stabilized emulsion displayed higher viscosity compared to PT-MP emulsions. Frequency sweep results showed that GG-MP, GA-MP, and LG-MP emulsions had greater elastic moduli (G') than viscous moduli (G"), indicating elastic behavior, whereas PT-MP emulsions transitioned from liquid-like to solid-like behavior as frequency increased. This study illustrates the advantages of high LG and PT content in preventing particle aggregation and enhancing emulsion stability, providing a theoretical and practical foundation for MP applications in food processing.

Enhanced Photocatalysis via Inverse Opal Structures: Synthesis and Characterization of TiO2/ZnO and ZnO/TiO2 Composites Using Plasma-Enhanced ALD

Inverse opals (IO) based functional materials show potential in photocatalysis due to their unique light interaction properties. This study presents a low-temperature plasma-enhanced atomic layer deposition (PEALD) method for synthesizing TiO2, ZnO, and composite IOs using a polystyrene nanoparticle-based opal template. We comprehensively characterized the obtained materials using SEM-EDX, TSEM, TG, FTIR, XRD, Raman, ellipsometry, photoluminescence (PL), and UV-Visible spectroscopy. SEM analysis confirmed the successful formation of PEALD IOs with a periodically ordered structure, enabling conformal coating while preserving their original architecture. XRD and Raman analysis also confirmed that the IOs consisted of anatase for TiO2 and hexagonal wurtzite for ZnO. UV-Vis reflectance spectroscopy revealed strong UV absorption and modified photonic bandgaps (PBGs) for all materials. The bare and composite IOs exhibited PBGs in the visible region, suggesting that the arising "slow photon" effect might enhance photocatalysis. This study explored the photocatalytic degradation of 4-Nitrophenol (4-NP) and Rhodamine 6G (Rh6G) using pristine and composite IO photocatalysts under UV and visible light irradiation. Pristine TiO2 and ZnO IOs demonstrated superior performance for 4-NP degradation under UV light. This can be attributed to two key factors: their highly ordered macroporous structure (with a large surface area for efficient dye adsorption, and their band gaps (3.0 eV for TiO2 and 3.2 eV for ZnO) that enable strong absorption of UV light photons for effective pollutant degradation. Conversely, composite IOs (TiO2/ZnO and ZnO/TiO2) displayed higher activity for both test molecules under visible light due to a synergistic effect between bandgap harmonization and the PBG effect.

Novel multi-layered MXene as laser desorption ionization mass spectrometry matrix for rapid detection of small biomolecules

Five two-dimensional multi-layered MXenes namely MO2C, Ti2C, V2C, Nb2C and Ta2C were synthesized by a one-step exfoliation process and evaluated as laser desorption ionization mass spectrometry (LDI-MS) matrices for fast detection of small biomolecules for the first time. Among them, Nb2C exhibited the best performance due to its high carrier mobility, strong photo-induced charge transfer resonance and good UV absorption ability. A simple, universal and efficient LDI-MS platform was established for small biomolecule analysis based on the Nb2C matrix. Key factors that affect LDI-MS efficacy were investigated and the established method demonstrated ultraclean MS background, high sensitivity with detection limits low to fmol level and good reproducibility. The Nb2C-based LDI-MS platform was successfully applied in the rapid determination of 13 amino acids (AAs) in human serum and 3 AAs, as potential biomarkers, were found to be significantly down-regulated in major depressive disorder patients. This work proved the feasibility of Nb2C MXene as an LDI-MS matrix and provided a promising and universal platform for the rapid detection of small molecules in biomedical research.

Preparation of fluorescent carbon dots by flow-assisted melt polymerization for tetracycline detection in medical wastewater

Tetracycline (TC) is one of the most important therapeutic drugs that is widely used in hospitals. However, its harmful effects on human health and various ecosystems cannot be ignored. Owing to its poor metabolic activity and low biodegradability, TC commonly discharges as the parent compound and accumulates readily in sludges and soils by precipitation from wastewater, which can induce the evolution of antibiotic-resistant bacteria; therefore, it has been listed as one of the new pollutants with potential ecotoxicological risk. The control measures and environmental management of TC pollutants in environmental water samples require precise determination of TC pollutant concentrations. Carbon dots (CDs) are an emerging type of fluorescent material with numerous advantages such as easy preparation, low cost, low toxicity, and good biocompatibility. Consequently, they have attracted widespread attention in the field of TC detection. Herein, we synthesized TE-CDs with good blue-fluorescence performance via flow-assisted melt polymerization using tricarboxylic acid and ethylenediamine as raw precursors. The morphology and structure of the prepared TE-CDs were characterized. The transmission electron microscopy (TEM) results showed that the prepared TE-CDs were well dispersed, with an average diameter of (2.43±0.48) nm. The X-ray diffraction (XRD) results showed that the TE-CDs had an amorphous carbon structure. Infrared spectroscopy and X-ray photoelectron spectroscopy (XPS) characterizations showed that the surface of the TE-CDs was rich in hydrophilic groups, such as amino, hydroxyl, and carboxyl groups, which indicated that TE-CDs had good water solubility and were advantageous for detecting TC in medical wastewater. Subsequently, the optical properties of the TE-CDs were investigated. The fluorescence emission spectra of the TE-CDs were recorded at various excitation wavelengths. The emission spectra of the TE-CDs exhibited excitation wavelength dependence and when the excitation wavelength changes from 300 nm to 400 nm, their fluorescence intensity decreased to varying degrees. The TE-CDs exhibited optimal fluorescence intensity at an excitation wavelength of 368 nm, while the emission wavelength was 448 nm. TC could effectively quench the blue fluorescence of the CDs, and by utilizing this property, the detection of TC concentration could be achieved. After the addition of TC, the fluorescence of the system immediately reached an extreme value, and no significant change was observed within 10 min. An incubation time of 20 s was selected to obtain precise results. Additionally, the TE-CDs exhibited stable fluorescence intensity over a wide pH range. The fluorescence stability of the TE-CDs was investigated, and no significant change in fluorescence intensity was observed after standing for 10 d, indicating that the prepared TE-CDs had excellent fluorescence stability. The fluorescence intensity of the TE-CDs decreased to varying degrees within the range of 2-200 mg/L TC until complete quenching occurred. TC mass concentration in the range of 4-20 mg/L showed a good linear relationship (R2=0.9978) with the fluorescence quenching intensity of the TE-CDs. The limit of detection was 0.2 mg/L. A preliminary investigation was undertaken to explore the quenching mechanism of the TE-CDs fluorescence by TC. Upon addition of TC, a significant reduction in the fluorescence lifetime of the TE-CDs was observed. During the quenching process, no new substances were observed by UV absorption spectroscopy. Additionally, no significant changes in the 1H NMR spectra of the TE-CDs were noted before and after the addition of TC, indicating the absence of an interaction between the TE-CDs and TC. Therefore, the quenching mechanism may involve dynamic quenching. The selectivity and anti-interference ability of the developed method were evaluated; in the presence of interfering substances, TC quenched the fluorescence of the TE-CDs, indicating that the TE-CDs had good selectivity and anti-interference performance towards TC. The method was applied to the quantitative detection of TC in medical wastewater, with recoveries of 96.5%-119.8% and relative standard deviations of 0.8%-2.6%. In conclusion, the analytical performance of the proposed method is comparable with that of previously reported detection methods; moreover, the method has the advantages of low operational cost, simple preparation process, time-saving, and good repeatability. Therefore, the TE-CDs can be used as chemical sensors for the detection of TC in medical wastewater and have good practical applications.

Application of Fenton’s Reaction for Removal of Organic Matter from Groundwater

In this study, the effectiveness of the Fenton process in removing natural organic matter (NOM) from groundwater was investigated. The subject of this study is groundwater characterised by increased content of NOM and iron (II) compounds. In laboratory-scale studies, the influence of the ratio of concentrations of Fe(II) ions, which are naturally occurring in groundwater, to hydrogen peroxide (H2O2) as well as oxidation time and pH on the removal efficiency of organic matter was determined. Indicators such as total organic carbon (TOC), dissolved organic carbon (DOC), UV absorbance at 254 nm (UV254), UV absorbance at 272 nm (UV272), and specific UV absorbance (SUVA254) were used to quantitatively and qualitatively assess the organic substances present in the raw water and after oxidation with Fenton’s reagent. Analysis of the results obtained showed that the highest removal efficiency of organic substances in the deep oxidation process using the Fenton reaction was obtained for a concentration ratio of Fe(II) to H2O2 = 1:5. Acidification of the water samples to a pH of about 4 and extending the oxidation time to 30 min significantly increased the removal efficiency of organic substances including mainly dissolved organic substances containing aromatic rings. The organic substances containing aromatic rings, determined at a wavelength of 254 nm, were degraded to other organic intermediates.

Solid‐phase synthesis of grafted carbon black for superior aging resistance in biodegradable poly(butylene adipate‐co‐butylene terephthalate) composite films

AbstractBiodegradable films mitigate plastic pollution but often lack UV‐aging resistance, shortening their lifespan. While anti‐aging additives can boost the films' durability, small molecule migration constrains the extension of their service life. This study introduces a straightforward solid‐phase reaction for producing carbon black (CB) grafted with the UV absorber UV531, termed CB‐UV531. This material was then blended with the biodegradable polymer PBAT and transformed into a film via blow molding, yielding a durable UV‐resistant biodegradable film (PBAT/CB‐UV531). This solid‐phase grafting reaction does not require any solvents, thereby reducing solvent contamination and waste, and it is simple to operate, allowing for scalable production. Compared to the unmodified CB, the obtained CB‐UV531 exhibits significantly improved thermal stability, which can effectively reduce the loss of UV531 during the subsequent high‐temperature film‐blowing process. Furthermore, the chemically bonded UV absorber on the surface of CB‐UV531, coupled with its reduced particle size, promotes enhanced dispersibility and consistent stability within the PBAT/CB‐UV531 film, markedly improving its long‐term resistance to UV aging. This method is expected to enhance the anti‐aging effects of various commercial light stabilizer additives and can be used to extend the lifespan of different biodegradable materials.Highlights A simple solid‐phase reaction method was developed to prepare CB‐UV531. CB‐UV531 reveals smaller size and superior dispersibility. Biodegradable PBAT/CB‐UV531 film was prepared via a blowing process. UV531 migration loss in PBAT/CB‐UV531 film is significantly reduced. PBAT/CB‐UV531 film shows enhanced thermal stability and aging resistance.

Synthesis and characterization of new organometallic lanthanides metal complexes for photodynamic therapy

New Schiff base ligand: 4-methoxy salicaldhyde-2-2-phenyl-hydrazono acetaldehíyde prepared by facile method. The molecular structures characterized by elemental analysis and proton magnetic resonance spectra (1H-NMR spectra). This spectra at the chemical shifts (3.5–10.39 ppm) confirmed the types and the numbers of protons. The sharp melting point at the range 110–112 °C confirmed purity. New optically active metal (samarium, terbium and gadolinium) complexes of the Schiff base synthesized in a one pot reaction. Vibrational IR spectra confirmed functional groups. Scanning electron microscopy micrographs confirmed that the modified microstructure of the metal complexes differed in morphology than the ligand. Powder X-ray diffraction patterns confirmed good crystalline structure. The optically activity of the solid metal complexes confirmed from electronic absorption spectra. The UV absorbance band at the wavelength range 280–390 nm and the intense phosphorescence bands up to 830 nm enabled application in photo dynamic therapy for apoptosis cancer cells by conversion triplet oxygen in the tissues into reactive singlet oxygen. Low charge transfer energy: 2.59–2.61 eV, high molar extinction coefficients (ε) at the order of magnitude \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\:{10}^{6}$$\\end{document} M− 1 cm− 1 and the intense phosphorescence bands reflected good photodynamic activity. The metal complexes are thermally stable.

The preparation of fish scale gelatin-polydopamine photothermal sterilization film and its application for storage of cherry tomato

In this study, polydopamine nanoparticles (PDA NPs) were synthesized and fish scale gelatin (FSG) was extracted by hot water hydrolysis. The film for photothermal sterilization was created by casting FSG with the addition of PDA NPs. The results indicated that the PDA NPs were able to heat up to 46 °C in 5 min under near-infrared (NIR), demonstrating good photothermal conversion. The PDA NPs/FSG solution showed short-term bactericidal activity against Staphylococcus aureus and Escherichia coli, with a bactericidal rate of more than 99 %. The PDA NPs/FSG film could warm up to 42.6 °C under NIR irradiation for 5 min. With the addition of 0.3 % of PDA NPs, the PDA NPs/FSG films showed high UV absorption, DPPH and ABTS radical scavenging ability, and high water contact angle (WCA), improving the barrier to water and oxygen and the tensile strength. The 0.3 % PDA NPs/FSG film triggered by NIR effectively maintained the firmness, soluble solids content and appearance, and delayed the weight loss of cherry tomatoes. Thus, the PDA NPs/FSG films had good photothermal antimicrobial activity and could be used for extending the shelf life of cherry tomatoes.

Computational metal-flavonoids complexes presentation of greenly synthesized silver nanoparticles combined flavonoids from Lens culinaris L. as anticancer agents using BcL-2 and IspC proteins

Lens culinaris L., has been widely recognized for its medical applications. LC-ESI-TOF-MS identified 22 secondary metabolites including phenolics, flavonoids, and anthocyanidin glycosides among its total extract (LCTE). The study aimed to apply LCTE as a biogenic material for reducing and capping the silver nanoparticles (LC-AgNPs). The ynthesized LC-AgNPs were characterized using different techniques. The UV absorption was observed at λ max 379 nm. LC-AgNPs were spherical, with 19.22 nm average size. The face cubic centre nature was demonstrated by HR-TEM and XRD. The LC-AgNPs were then evaluated for their anticancer and antimicrobial potentials. LC-AgNPs showed an extremely potent cytotoxic activity against MCF-7, HCT-116 and HepG2 cell lines (IC50= 0.37, 0.35 and 0.1 µg/mL, respectively). LC-AgNPs induced significant apoptotic effects in the three examined cancer cell lines. LC-AgNPs resulted in sequestration of cells in G1 phase of the cell cycle in both MCF-7 and HCT-116 cells, meanwhile it trapped cells at the G2 phase in HepG2 cells. Moreover, the antimicrobial activity of LC-AgNPs was highly confirmed against Klebsiella pneumoniae and Acinetobacter baumannii. Molecular docking study designated Kaempferol-3-O-robinoside-7-O-rhamnoside and Quercetin-3-D-xyloside as the topmost LCTE active constituents that caused inhibition of both Bcl-2 and IspC cancer targets in combination with the produced silver nanoparticles.

Bacterial Responses and Material-Cell Interplays With Novel MoAlB@MBene.

Developing efficient antibacterial nanomaterials has potential across diverse fields, but it requires a deeper understanding of material-bacteria interactions. In this study, a novel 2D core-shell MoAlB@MBene structure is synthesized using a mild wet-chemical etching approach. The growth of E. coli, S. aureus, and B. subtilis bacteria in the presence of MoAlB@MBene decreased in a concentration-dependent manner, with a prolonged lag phase in the initial 6h of incubation. Even under dark conditions, MoAlB@MBene triggered the formation of intercellular reactive oxygen species (ROS) and singlet oxygen (1O2) in bacteria, while the bacteria protected themselves by forming biofilm and altering cell morphology. The MoAlB@MBene shows consistent light absorption across the visible range, along with a distinctive UV absorption edge. Two types of band gaps are identified: direct (1.67eV) and indirect (0.74eV), which facilitate complex light interactions with MoAlB@MBene. Exposure to simulated white light led to decreased viability rates of E. coli (20.6%), S. aureus (22.9%), and B. subtilis (21.4%). Altogether, the presented study enhances the understanding of bacteria responses in the presence of light-activated 2D nanomaterials.

Transparent Coating Systems Applied on Spruce Wood and Their Colour Stability on Exposure to an Accelerated Ageing Process

The objective of this study was to investigate the colour stability of spruce wood surfaces treated with coating systems (CS) and exposed to accelerated ageing. The tested CSs were transparent and three-layered; the top layer was modified with ultraviolet (UV) absorbers, while the base layer was modified with lignin stabiliser. Spruce wood surfaces treated with unmodified CSs were not colour-stable during the accelerated ageing process, with the surface exhibiting colour change after just 100 ageing hours. Adding specific UV absorbers into the top layer and lignin stabiliser into the base layer significantly improved the colour stability of the surface-treated wood. In all cases, however, the colour variation associated with ongoing ageing was significant. An additional study task was to determine whether the discolouration of surface-treated wood is caused by the discolouration of the wood substrate alone or also by the CS discolouration. Consequently, there was also the examination of discolouration of the individual coating materials or coating systems applied to glass slides. This testing proved that in the case of wood surface-treated with CS, without lignin stabiliser, the discolouration was the same as that of the substrate, and this was true throughout the whole ageing process. In the case of wood surface-treated with CS, but with lignin stabiliser, there were, in some cases, significant differences in discolouration between surface-treated wood and the wood substrate. These variations were especially evident during the initial 300 ageing hours.

Exploiting the Bragg Mirror Effect of TiO2 Nanotube Photonic Crystals for Promoting Photoelectrochemical Water Splitting

Exploiting the Bragg mirror effect of photonic crystal photoelectrode is desperately desired for photoelectrochemical water splitting. Herein, a novel TiO2 nanotube photonic crystal bi-layer structure consisting of a top nanotube layer and a bottom nanotube photonic crystal layer is presented. In this architecture, the photonic bandgap of bottom TiO2 nanotube photonic crystals can be precisely adjusted by modulating the anodization parameters. When the photonic bandgap of bottom TiO2 nanotube photonic crystals overlaps with the electronic bandgap of TiO2, the bottom TiO2 nanotube photonic crystal layer will act as a Bragg mirror, leading to the boosted ultraviolet light absorption of the top TiO2 nanotube layer. Benefiting from the promoted UV light absorption, the TiO2 NT-115-NTPC yields a photocurrent density of 1.4 mA/cm2 at 0.22 V vs. Ag/AgCl with a Faradic efficiency of 100%, nearly two times higher than that of conventional TiO2 nanotube arrays. Furthermore, incident photon-to-current conversion efficiency is also promoted within ultraviolet light region. This research offers an effective strategy for improving the performance of photoelectrochemical water splitting through intensifying the light–matter interaction.