The Royal Society of Chemistry最新文献

This study aimed to produce bilayer films spiked with white round grapefruit essential oil and apply them to preserve Lycium barbarum. A chitosan/polyvinyl alcohol film doped with white round grapefruit essential oil was prepared as an inner film, and a polyethylene terephthalate film was prepared as an outer film through a solution casting method. The volatile compounds of white round grapefruit essential oil (87.5573%), mainly D-limonene (34.389%), cis-p-mentha-2,8-dien-1-ol (5.154%), trans-carveol (5.148%), limonene oxide, cis-β-ocimene (4.892%) and trans-β-ocimene (4.130%), were identified through gas chromatography-mass spectrometry and found to have strong antimicrobial activities against Escherichia coli, Staphylococcus aureus, and Aspergillus niger. The addition of white round grapefruit essential oil to the chitosan/polyvinyl alcohol film resulted in a significant improvement in the flexibility and antimicrobial properties of the films; the thermomechanical properties were more stable; however, the film water content and soluble solid content changes were not significant. The double-layer film was applied in the preservation of Lycium barbarum, and results showed that the double-layer film effectively reduced the water loss rate, decay rate, malondialdehyde content, and color change of Lycium barbarum compared with the control group and prolonged the shelf-life of Lycium barbarum.

Manganese-oxidizing bacteria (MnOB) and biogenic manganese oxides (BioMnOx) play key roles in the breakdown of organic matter (including pollutants) in water and soil environments. The degradation of some organic compounds (such as sulfonamides selected in this study) by BioMnOx in the presence of active MnOB is poorly understood. Thus far, it has been shown that the transformation of sulfonamides by either BioMnOx or MnOB (but thus far not studied in a binary system) can be modulated using naturally occurring redox mediators, such as humic substances, leading to the formation of coupling products of unknown stability. The co-occurrence of sulfonamides, MnOB, BioMnOx, and humic constituents is pertinent to many natural and engineered settings. This study used syringaldehyde, which is a model humic constituent, to investigate the nature of modulation in a binary system of BioMnOx and MnOB for the first time. The MnOB strain Pseudomonas putida MnB6 was cultivated and used in batch degradation tests. Initial tests with eight sulfonamides showed comparably poor degradation. In the next step of this study, sulfamethoxazole (SMX) and two SMX submoieties (sulfanilamide (SNM) and 3-amino-5-methylisoxazole (ISX)) were examined. After 48-60 hours in active cultures with BioMnOx, the degradation of all the three substances was negligible. However, syringaldehyde increased the degradation efficiency by 26% for SMX, 58% for SNM, and 27% for ISX. The active culture and BioMnOx synergistically improved degradation, highlighting the importance of BioMnOx regeneration. Removal was partially reversible (10-30%) owing to the retransformation of the reaction products into parent compounds, which was induced by syringaldehyde depletion. Unstable reaction products were conjugates of SMX, SNM, and ISX with syringaldehyde or its oxidation product DMBQ (2,6-dimethoxy-1,4-benzoquinone). This deconjugation likely contributes to process reversibility, potentially negatively impacting the environment and the safety of water and wastewater treatment systems.

Judiciously combined modality approaches have proved highly effective for treating most forms of cancer, including glioblastoma. This study introduces a hybrid nanoparticle-based treatment designed to induce a synergistic effect. It employs repurposed celecoxib-loaded hybrid nanoparticles (HNPs) that are thermally activated by near-infrared laser irradiation to damage glioblastoma cells. The HNPs are constructed by covalently binding organic (ultra-small nanostructured lipid carriers, usNLCs) and inorganic nanoparticles (gold nanorods, AuNRs, with photothermal therapy capability), using c(RGDfK) that serves the dual purpose of a biolinker and a tumor-targeting peptide. The HNPs are further functionalized with transferrin (Tf) as a blood-brain barrier ligand denoted as HNPs^Tf. Our comprehensive in vitro and in vivo studies have unveiled the remarkable capability of HNPs^Tf to safely and specifically increase blood-brain barrier permeability through transferrin receptor interactions, facilitating precise nanoparticle accumulation in the tumor region within orthotopic tumor-bearing mice. Furthermore, the orchestrated combination of chemo- and photothermal therapy has exhibited a substantial therapeutic impact on glioblastoma, showcasing a noteworthy 78% inhibition in tumor volume growth and an impressive 98% delay in tumor growth. Notably, this treatment approach has resulted in prolonged survival rates among tumor-bearing mice, accompanied by a favorable side effect profile. Overall, our findings unequivocally demonstrate that celecoxib-loaded HNPs^Tf offer a game-changing, chemo-photothermal combination, unleashing a synergistic effect that significantly enhances both brain drug delivery and the efficacy of anti-glioblastoma treatments.

Nanoparticles of Dy-doped Fe_1.4Bi_0.6Y_0.5Se_2.5−x (x = 0, 0.1, 0.2, 0.3) were synthesized using the sol–gel method. The effects of Dy doping on the microstructural, thermal, magnetic, and electrical properties of Fe_1.4Bi_0.6Y_0.5Se_2.5−x nano-crystallites were investigated. X-ray diffraction (XRD) analysis confirmed higher crystallinity in undoped Fe_1.4Bi_0.6Y_0.5Se_2.5. At higher Dy concentrations (x: 0.1, 0.2, 0.3), a few peaks corresponding to the DyFeO₃ phase appeared. Morphological analyses (SEM/TEM) and FTIR spectra revealed Dy-induced microstructural modifications, including an increase in particle size to 25–27 nm and alterations in Bi–O–Dy vibrations. Thermal analysis demonstrated dehydration-induced weight loss and excellent thermal stability up to 600 °C. Magnetic measurements indicated a transition from ferromagnetic to superparamagnetic with Dy doping, alongside superparamagnetic tendencies at higher Dy concentrations. Electrical measurements showed a transition from semiconducting to metallic behavior, with conductivity increasing at higher frequencies and temperatures, suggesting thermally activated conduction mechanisms. These findings confirm that Dy³⁺ incorporation significantly influences the internal structure of Bi_0.6Fe_1.4Se_2.5Y_0.5 nanoceramics, enhancing their magnetoelectric properties. The improved structural, thermal, magnetic, and electrical characteristics make Dy-doped Bi_0.6Fe_1.4Se_2.5Y_0.5 nanoceramics promising candidates for applications in microelectronics, topological quantum devices, and spintronics.

Odorous gas emission is one of the world's seven major public nuisances, easily causing disturbances and complaints, and posing a threat to air quality and public health. Emissions of odorous substances are characterized by their sudden and instantaneous nature, with some odorous compounds having extremely low olfactory thresholds. Therefore, it is essential to develop highly sensitive on-site rapid detection techniques. This paper presents a new technology that combines a cluster hollow fiber membrane (CHFM) with mobile proton transfer reaction mass spectrometry (PTR-MS), developing a cluster hollow fiber membrane-proton transfer reaction mass spectrometry (CHFM-PTR-MS) technique. Due to the large membrane area (1000 cm²) of the cluster hollow fiber membrane module, the CHFM-PTR-MS shows improved sensitivity for eight tested odorous substances by 7.6 to 12.2 times and an enhanced limit of detection by 6.7 to 12.4 times compared to traditional direct-injection PTR-MS. Through a 28-hour continuous monitoring experiment of odorous gases released from household waste, the capability of the new CHFM-PTR-MS technology for on-site rapid detection of trace odorous organic compounds was verified. The CHFM-PTR-MS is expected to provide a new technique and device for on-site rapid detection of odorous organic compounds with high sensitivity.

Piezoelectricity in biological soft tissues is a controversial issue with differing opinions. While there is compelling experimental evidence to suggest a piezoelectric-like response in tissues such as the aortic wall (among others), there are equally compelling experiments that argue against this notion. In addition, the lack of a polar structure in the underlying components of most soft biological tissues supports the latter. In this paper, we address the collective behavior of cells within a two-dimensional cell aggregate from the viewpoint of statistical mechanics. Our starting point is the simplest form of energy for cell behavior that only includes known observable facts e.g., the electrical Maxwell stress or electrostriction, resting potential across cell membranes, elasticity, and we explicitly exclude any possibility of electromechanical coupling reminiscent of piezoelectricity at the cellular level. We coarse-grain our cellular aggregate to obtain its emergent mechanical, physical, and electromechanical properties. Our findings indicate that the fluctuation of cellular strain (E) plays a similar role as the absolute temperature in a conventional atomistic-level statistical model. The coarse-grained effective free energy reveals several intriguing features of the collective behavior of cell aggregates, such as solid-fluid phase transitions and a distinct piezoelectric-like coupling, even though it is completely absent at the microscale. Closed-form formulas are obtained for key electromechanical properties, including stiffness, effective resting potential, critical E²-temperature (or fluctuation) for solid-fluid phase transitions, and apparent piezoelectric coupling in terms of fluctuation and electric potential regulated by active cellular processes.

Vinca alkaloids represent a major class of antineoplastic agents used against cancer. They are prepared in centralized production units by pharmacy technicians. Control of the preparation is indispensable to secure their preparation and avoid any errors, which can have serious consequences for the patient because antineoplastic agents are very toxic. Analytical quality control was proven to be the most efficient control to ensure the right drug at the right dose to the patient. The study focused on vinca alkaloids: vinblastine, vincristine, vindesine, vinflunine, and vinorelbine, in the form of commercially diluted solutions in 0.9% NaCl at therapeutic concentrations. The aim of this study was to develop an analytical methodology for quality control capable of discriminating and quantifying these molecules. The primary objective was to assess the capability of Flow Injection Analysis with UV detection (FIA-UV), combined with chemometrics, for rapid classification and quantification of these alkaloids. A rapid High-Performance Liquid Chromatography with UV-visible detection (HPLC-UV) method was also developed and established as a reference standard. HPLC-UV discrimination was based on retention time, whereas FIA-UV relied on spectral analysis. Therefore, to improve discrimination in FIA-UV, Partial Least Squares Discriminant Analysis (PLS-DA) was incorporated. FIA-UV achieved 100% sensitivity and specificity in discriminating the five alkaloids, demonstrating non-inferiority to HPLC-UV. This method offers a streamlined workflow, reduces iatrogenic risk, and is well suited for antineoplastic agent preparation environments.

Water quality of small rivers in the Ulba basin has been assessed in the impact zone of the mining industry of the Ridder region in East Kazakhstan. Sixteen elements in the waters of small rivers and general chemical water indices were determined using mass spectrometry. The waters of the small rivers under investigation were primarily ultra-fresh and slightly alkaline. The chemical composition of the examined waters was characterised as a sodium–potassium sulphate type, a calcium–magnesium bicarbonate type, and a mixed chemical type, namely, sodium–calcium bicarbonate–sulphate. These waters do not conform to the Health Standards established by the Republic of Kazakhstan, as indicated by the hardness indices for the Filippovka and Bystrukha riv. The cadmium content exceeded the MPC set by the Health Standards of the Republic of Kazakhstan in the waters of the Ulba riv. (up to 21 MPC), Tikhaya (up to 5 MPC) and Filippovka riv. (up to 3 MPC) in 65%, 88% and 18% of water samples, respectively. Single samples were also found to contain elevated concentrations of manganese (Filippovka riv. and Breksa riv.) and ferrum (Breksa riv.). According to the standards set by the World Health Organization (WHO) and the US MPC, exceedances of manganese, aluminium, iron, and cadmium contents in the waters of the Ulba, Filippovka, Breksa, and Bystrukha rivers were observed, ranging from 1 to 7 times. The highest exceedances were recorded in the waters of the Ulba river, with manganese concentrations exceeding the WHO standards by 4 times and US EPA standards by 6.4 times and cadmium concentrations exceeding the WHO standards by 7 times and US EPA standards by 4.2 times. In most water samples from Tikhaya and Ulba riverbeds and in the upper reach of the Filippovka riv, high and average levels of water contamination were revealed (according to the pollution index of heavy metals (HPI)). Alternatively, low contamination levels (<15) with no elevated concentrations of heavy metals were observed in the waters of Zhuravlikha, Malaya Zhuravlikha, Gromotukha, Khariuzovka, Bystrukha and Breksa.

Developing high-performance, multifunctional non-precious metal catalysts is essential for enhancing the efficiency of future energy utilization. In this study, four types of magnetic, recyclable Co₃Fe₇/CoFe₂O₄ incorporated porous carbon composite catalysts were synthesized using citric acid as the carbon source and ammonium chloride (NH₄Cl) as the salt medium. Iron and cobalt salts, in four different proportions, were uniformly incorporated using freeze-drying technology and subsequently processed through in situ calcination. Among the synthesized catalysts, Co₃Fe₇/CoFe₂O₄@NC-1, demonstrated outstanding catalytic reduction performance, with a reaction rate constant (k) of 0.031 min⁻¹, along with excellent cycle stability for 4-NP. The resulting Co₃Fe₇/CoFe₂O₄@NC-3 catalyst exhibited good ORR activity in an alkaline medium (E_onset = 0.99 V, E_1/2 = 0.83 V, J_L = −5.2 mA cm⁻²), along with long-term durability and resistance to methanol poisoning. These hybrid materials hold promise as non-precious metal electrocatalysts for fuel cell ORRs and introduce a new class of catalytic candidates for 4-NP reduction.

Based on the known Wnt agonist BML-284, we designed and synthesized photoswitchable azo derivative compounds that can act as agonists for the Wnt signaling pathway. These photoswitchable agonists were shown to undergo reversible trans-cis isomerization upon being irradiated with visible light, but only the cis isomer was observed to activate the Wnt signaling pathway, using a luminescense-based reporter assay in cultured cells. One of the compounds, denoted as compound 2, showed ∼88% agonist activity after being subjected to visible light irradiation in comparison to the non-photoswitchable BML-284. We also were able to selectively activate the Wnt signaling pathway using 2 and light irradiation at a specific region of interest in a model cell culture system, highlighting the ability to achieve spatiotemporal regulation.