Frontiers in Chemistry最新文献

Piezoelectric materials have emerged as promising non-thermal, chemical-free sterilization agents, offering clear advantages over traditional methods such as heat, UV, or disinfectants. Their antimicrobial activity arises from direct microbial membrane disruption and reactive oxygen species (ROS) generation under mechanical stimuli like ultrasound or vibration via piezodynamic reactions. These approaches preserve material integrity, making them ideal for implants, wound dressings, and biofilm prevention. Recent advances focus on enhancing piezoelectricity via defect engineering, dopants, and band structure optimization to improve ROS production. This review highlights progress in piezoelectric materials as smart, sustainable antimicrobial platforms with broad biomedical and environmental applications.

Production of nano-sized solid-dosage drugs is useful for pharmaceutical industry owing to high solubility and efficacy of the drugs for patients, which can also reduce the drugs side effects. For the solid-dosage oral formulations, the nanomedicine can be prepared via either top-down or bottom-up approach to enhance the drug solubility which in turns enhances the drug bioavailability. A novel methodology for simulation and prediction of medicine solubility in supercritical solvent was developed based on supervised learning algorithms for classification of the data. The data for the simulations were collected on solubility of a model drug in supercritical carbon dioxide. The supercritical-based processing is usually used for preparation of nanomedicine with enhanced bioavailability, and the developed simulation method can help design and optimize the process for industrial applications. The data was obtained with temperature and pressure as the input parameters, whereas the drug solubility is considered as sole estimated output in the model. The validation outputs indicated that great agreement was obtained between the measured data and the simulated values with acceptable regression coefficient for the whole simulations. The simulation results revealed that the supervised learning algorithm is robust and rigorous for prediction of drug solubility data in supercritical conditions and can be used for process optimization and understanding the effects of process parameters. This study is innovative as it methodically assesses diverse machine learning methodologies, encompassing polynomial regression at different complexity tiers and the Gaussian Process Regressor for predicting pharmaceutical solubility. This comparative framework illustrates the bias-variance tradeoff and offers pragmatic guidance for choosing suitable models according to dataset attributes. The methodology presents a time-efficient and cost-effective alternative to conventional thermodynamic modelling for supercritical pharmaceutical processing.

Organic liquids immiscible with water, such as volatile organic compounds (VOCs) and plasticizers are widespread harmful environmental pollutants, which have long been considered a risk factor for chronic diseases in humans. VOCs or plasticizers in the outdoor environment largely originate from industrial manufacturing, combustion and leakage of transportation fuels, and biological metabolism. Consequently, in order to protect the environment and human health, there is an urgent need for point-of-need sensors for VOCs as well as plasticizer detection. Fluorimetric sensors are emerging attractive tool for monitoring concentration changes of these analytes in environmental samples, that can reduce need for advanced, instrumental methodologies. Various fluorescence-based strategies have already been demonstrated, with turn-on fluorescence approaches being particularly promising. These strategies are based on the interaction of fluorometric dyes or conjugated polymers embedded in polymeric matrices with the target analytes. The proposed approaches show great potential for real-time monitoring of hazardous pollutants in environmental applications, offering cost-efficient, simple, and portable alternatives to conventional analytical techniques. However, it is worth emphasizing that despite the great variety of research topics, the current state of knowledge does not exhaust this field, and many challenges still remain to be overcome.

An organoammonium-dihydrogenphosphate compound (C₇H₁₁N₂)H₂PO₄ was synthesized and characterized. The intra-and intermolecular interactions responsible for the stability of our compound within the crystal lattice have been thoroughly discussed. FT-IR spectroscopic analyses have confirmed the well atomic organization and stability of our compound. Using the RDG and NCI approaches, we identified strong N-H···O and O-H···H hydrogen bonds, along with notable van der Waals (vdW) interactions between the cationic units and the phosphate anion, confirming the key role of non-covalent forces in stabilizing the crystal structure. Intermolecular interactions were further elucidated by Hirshfeld surface analysis. Moreover, dispersion-corrected Density Functional Theory provided insights into chemical reactivity properties. The compound was also analyzed using solid-state spectroscopies. This contribution enhances the understanding of the structural diversity of organic-dihydrogenphosphate compounds.

Hydrogen sulfide (H₂S) generated by industrial processes (such as petroleum refining, natural gas purification, and coal processing) is a highly toxic and corrosive gas, which is detrimental to human health and environment. Electrocatalytic decomposition of H₂S for simultaneous desulfurization and hydrogen production has emerged as a promising approach to addressing environmental pollution whilst achieving valuable utilization of H₂S. Currently, there are two pathways for electrochemical decomposition of H₂S, namely, direct and indirect decomposition. For the direct pathway, H₂S is electrocatalytically oxidized into sulfur at anode using electrocatalysts. However, this approach is hindered by electrocatalyst deactivation due to sulfur passivation. Conversely, the indirect pathway effectively prevents the anodic sulfur passivation by introducing soluble redox couples as mediators, transferring H₂S oxidation reaction from electrode to liquid phase. In this regard, the selection of redox mediators is critical since it affects H₂S oxidation efficiency, sulfur purity, and overall decomposition voltage. In light of the challenges associated with above-mentioned electrochemical H₂S decomposition techniques, this review presents recent advancements in strategies to mitigate anodic sulfur passivation for direct decomposition method, as well as the development of redox mediators and process optimization for indirect decomposition method. Meanwhile, a comparative analysis of characteristic and reaction mechanism of both approaches is provided. Finally, perspectives are given on the current challenges and future research directions in the field of electrocatalytic H₂S splitting technology.

Garcinia cambogia (Gambogic Acid, GA) is a natural xanthone compound extracted from the resin of GA fruit, renowned for its diverse biological activities and substantial therapeutic potential. GA, a principal bioactive component of Garcinia cambogia, possesses a distinctive cage-like molecular architecture centered on an α,β-unsaturated ketone moiety. This structure is not merely a chemical signature but the fundamental source of GA's broad and integrated pharmacodynamic profile. While the multi-target nature of natural products like flavonoids has been widely documented, GA's unique polycyclic caged structure confers a different mechanism of action and a broader spectrum of activity, particularly in epigenetic reprogramming and the activation of multi-modal cell death networks. This review moves beyond a mere compilation of GA's effects to provide a systematic and critical analysis of its pharmacological landscape. We deconstruct its mechanisms along three integrated dimensions: (i) a molecular-level characterization of GA-regulated signaling pathways, emphasizing its multi-target synergy; (ii) an empirical evaluation of its therapeutic efficacy across cancer and inflammatory diseases, critically appraising both promises and limitations of current evidence; and (iii) an evidence-based discussion on overcoming translational barriers, with a focal point on how innovative nanodelivery strategies are pivotal in resolving GA's pharmacokinetic challenges. By directly comparing GA with other natural products (e.g., flavonoids) in terms of structure-activity relationships and translational potential, we highlight its unique position in the natural product pharmacopeia. We conclude that the future of GA research lies in the integration of multi-omics approaches with precision drug delivery systems, a synergistic strategy that will effectively bridge the gap between its robust mechanistic underpinnings and successful clinical application.

The substantial generation of hazardous, metal-enriched biomass residues poses significant risks of secondary contamination, presenting a critical bottleneck to the broader implementation of phytoremediation that urgently requires effective treatment solutions. This study addressed this challenge by pyrolyzing Pb-enriched biomass (BM_Pb) across a temperature range (300 °C-700 °C) to produce Pb-enriched biochar (BC_Pb), evaluating its efficacy for safe residue management. The results demonstrated that pyrolysis effectively reduced the volume of BM_Pb, and the produced BC_Pb significantly enriched and immobilized Pb. Element analysis revealed distinct stabilization mechanisms: Pb₂(P₄O₁₂) and PbCO₃ precipitation dominated Pb immobilization at 400 °C, whereas Pb₃(CO₃)₂(OH)₂, Pb₂(P₄O₁₂), and NaAlSiO₄ became predominant at temperatures ≥500 °C. Sequential extraction of Pb (BCR) demonstrated a consistent decline in the more labile Pb fractions (exchangeable, F1, and reducible, F2) with increasing pyrolysis temperature, concurrent with a significant increasing in the stable fractions (oxidizable, F3, and residual, F4). Notably, the combined F1+F2 fraction decreased substantially (17% at 700 °C), while the stable F3+F4 fraction increased correspondingly (83% at 700 °C), indicating markedly reduced Pb bioavailability and ecological risk at elevated temperatures. Leaching tests confirmed that Pb release from all BC_Pb samples remained well below relevant regulatory thresholds when the pH higher than 2 (<9.98 mg·g^-1 vs. 10.0 mg·g^-1), with leaching susceptibility inversely related to pyrolysis temperature. Soil simulation experiments further indicated a conversion of bioavailable Pb (F1+F2) in BC_Pb-amended systems towards stable forms (F3+F4), confirming low ecological risk. Overall, these findings suggested that pyrolysis of BM_Pb at temperatures above 500 °C shows great promise as an effective and safe method for treating phytoremediation residues, demonstrating high stability and low ecological risk to both water and soil environments under most natural conditions, though careful management is required under extreme acidic scenarios.

Photosensitizing systems based on methylene blue (MB)-loaded calcium alginate (CaA) and alginic acid (AA) aerogels were developed for photodynamic therapy of difficult-to-heal wounds. Hybrid aerogels incorporating polyvinylpyrrolidone (PVP, 2.5-40 wt%) into CaA and AA matrices were also made. The MB release kinetics in a phosphate buffer were found to depend on the aerogel type (AA or CaA). The incorporation of PVP increased the MB release rate by 1.5-2 times. The singlet oxygen (¹O₂) generation efficiency of MB embedded in the aerogels was influenced by their porosity and chemical composition. The activity of MB in the photogeneration of ¹O₂ increased by up to four times in the PVP-containing aerogels. Furthermore, the photoactivity of MB in the hybrid aerogel matrices significantly exceeded that in the single-component alginate aerogels.