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1.
Langmuir ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38739539

RESUMEN

In recent years, graphitic carbon nitride (g-C3N4) has attracted considerable attention because it includes earth-abundant carbon and nitrogen elements and exhibits good chemical and thermal stability owing to the strong covalent interaction in its conjugated layer structure. However, bulk g-C3N4 has some disadvantages of low specific surface area, poor light absorption, rapid recombination of photogenerated charge carriers, and insufficient active sites, which hinder its practical applications. In this study, we design and synthesize potassium single-atom (K SAs)-doped g-C3N4 porous nanosheets (CM-KX, where X represents the mass of KHP added) via supramolecular self-assembling and chemical cross-linking copolymerization strategies. The results show that the utilization of supramolecules as precursors can produce g-C3N4 nanosheets with reduced thickness, increased surface area, and abundant mesopores. In addition, the intercalation of K atoms within the g-C3N4 nitrogen pots through the formation of K-N bonds results in the reduction of the band gap and expansion of the visible-light absorption range. The optimized K-doped CM-K12 nanosheets achieve a specific surface area of 127 m2 g-1, which is 11.4 times larger than that of the pristine g-C3N4 nanosheets. Furthermore, the optimal CM-K12 sample exhibits the maximum H2 production rate of 127.78 µmol h-1 under visible light (λ ≥ 420 nm), which is nearly 23 times higher than that of bare g-C3N4. This significant improvement of photocatalytic activity is attributed to the synergistic effects of the mesoporous structure and K SAs doping, which effectively increase the specific surface area, improve the visible-light absorption capacity, and facilitate the separation and transfer of photogenerated electron-hole pairs. Besides, the optimal sample shows good chemical stability for 20 h in the recycling experiments. Density functional theory calculations confirm that the introduction of K SAs significantly boosts the adsorption energy for water and decreases the activation energy barrier for the reduction of water to hydrogen.

2.
J Pharm Sci ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38608727

RESUMEN

The preparation of amorphous solid dispersions (ASDs) represents a promising strategy for addressing the solubility limitations of poorly soluble drugs, facilitating enhanced oral absorption. Acidic polymers such as cellulose acetate phthalate (CAP) and hydroxypropyl methylcellulose phthalate (HPMCP) have emerged as effective carriers for ASDs. Although the hydrolytic degradation of these polymers has been documented, its impact on the stability of ASDs has not been systematically investigated. This research aimed to explore the potential hydrolysis of CAP and HPMCP and how it influences the stability of ASDs containing ketoconazole (KTZ), at drug loadings of 10 % and 50 %. Our study utilized thermal analysis, infrared spectroscopy, and evaluations of physical and chemical stability. The results revealed that although KTZ remained physically stable in all ASDs over 60 days under various stability conditions, the emergence of crystalline phthalic acid (PA), a byproduct of polymer hydrolysis, was observed at elevated temperatures and relative humidity levels. The acidic microenvironment fostered by the release of PA further catalyzed drug chemical degradation. This study underscores the susceptibility of CAP and HPMCP to hydrolytic degradation, highlighting the inherent risk of PA-induced drug degradation, particularly for acid-labile compounds. These insights into the understanding of polymer hydrolysis in ASDs pave the way for the development of targeted approaches to safeguard drug stability and optimize pharmaceutical formulations for enhanced bioavailability, efficacy, and safety.

3.
Mol Pharm ; 21(5): 2555-2564, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38551918

RESUMEN

Poloxamer 188 (P188) was hypothesized to be a dual functional excipient, (i) a stabilizer in frozen solution to prevent ice-surface-induced protein destabilization and (ii) a bulking agent to provide elegant lyophiles. Based on X-ray diffractometry and differential scanning calorimetry, sucrose, in a concentration-dependent manner, inhibited P188 crystallization during freeze-drying, while trehalose had no such effect. The recovery of lactate dehydrogenase (LDH), the model protein, was evaluated after reconstitution. While low LDH recovery (∼60%) was observed in the lyophiles prepared with P188, the addition of sugar improved the activity recovery to >85%. The secondary structure of LDH in the freeze-dried samples was assessed using infrared spectroscopy, and only moderate structural changes were observed in the lyophiles formulated with P188 and sugar. Thus, P188 can be a promising dual functional excipient in freeze-dried protein formulations. However, P188 alone does not function as a lyoprotectant and needs to be used in combination with a sugar.


Asunto(s)
Rastreo Diferencial de Calorimetría , Excipientes , Liofilización , Poloxámero , Trehalosa , Liofilización/métodos , Poloxámero/química , Excipientes/química , Trehalosa/química , Rastreo Diferencial de Calorimetría/métodos , Sacarosa/química , Difracción de Rayos X , L-Lactato Deshidrogenasa/metabolismo , L-Lactato Deshidrogenasa/química , Cristalización/métodos , Química Farmacéutica/métodos , Proteínas/química , Composición de Medicamentos/métodos , Congelación
4.
Cell Death Dis ; 15(2): 175, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38413563

RESUMEN

Immunotherapy has become a prominent first-line cancer treatment strategy. In non-small cell lung cancer (NSCLC), the expression of PD-L1 induces an immuno-suppressive effect to protect cancer cells from immune elimination, which designates PD-L1 as an important target for immunotherapy. However, little is known about the regulation mechanism and the function of PD-L1 in lung cancer. In this study, we have discovered that KEAP1 serves as an E3 ligase to promote PD-L1 ubiquitination and degradation. We found that overexpression of KEAP1 suppressed tumor growth and promoted cytotoxic T-cell activation in vivo. These results indicate the important role of KEAP1 in anti-cancer immunity. Moreover, the combination of elevated KEAP1 expression with anti-PD-L1 immunotherapy resulted in a synergistic effect on both tumor growth and cytotoxic T-cell activation. Additionally, we found that the expressions of KEAP1 and PD-L1 were associated with NSCLC prognosis. In summary, our findings shed light on the mechanism of PD-L1 degradation and how NSCLC immune escape through KEAP1-PD-L1 signaling. Our results also suggest that KEAP1 agonist might be a potential clinical drug to boost anti-tumor immunity and improve immunotherapies in NSCLC.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/genética , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Antígeno B7-H1/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Antineoplásicos/uso terapéutico
5.
Int J Pharm ; 653: 123905, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38355075

RESUMEN

The study aims to fabricate extended release (ER) tablets using a dual-nozzle fused deposition modeling (FDM) three-dimensional (3D) printing technology based on hot melt extrusion (HME), using caffeine as the model compound. Three different ER tablets were developed, which obtained "delayed-release", "rapid-sustained release", and "release-lag-release" properties. Each type of tablet was printed with two different formulations. A novel printing method was employed in this study, which is to push the HME filament from behind with polylactic acid (PLA) to prevent sample damage by gears during the printing process. Powder X-ray diffractometry (PXRD) and differential scanning calorimetry (DSC) results showed that caffeine was predominately amorphous in the final tablets. The dissolution of 3D printed tablets was assessed using a USP-II dissolution apparatus. ER tablets containing PVA dissolved faster than those developed with Kollicoat IR. Overall, this study revealed that ER tablets were successfully manufactured through HME paired with dual-nozzle FDM 3D printing and demonstrated the power of 3D printing in developing multi-layer tablets with complex structures.


Asunto(s)
Cafeína , Tecnología de Extrusión de Fusión en Caliente , Liberación de Fármacos , Comprimidos/química , Impresión Tridimensional , Tecnología Farmacéutica/métodos
6.
Cancer Cell Int ; 24(1): 13, 2024 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-38184573

RESUMEN

Gastric cancer remains a leading cause of cancer-related death worldwide, largely due to inadequate screening methods, late diagnosis, and limited treatment options. Liquid biopsy has emerged as a promising non-invasive approach for cancer screening and prognosis by detecting circulating tumor components like circulating tumor DNA (ctDNA) in the blood. Numerous gastric cancer-specific ctDNA biomarkers have now been identified. CtDNA analysis provides insight into genetic and epigenetic alterations in tumors, holding promise for predicting treatment response and prognosis in gastric cancer patients. This review summarizes current research on ctDNA biology and detection technologies, while highlighting clinical applications of ctDNA for gastric cancer diagnosis, prognosis, and guiding treatment decisions. Current challenges and future perspectives for ctDNA analysis are also discussed.

7.
Eur J Pharm Sci ; 192: 106625, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37918545

RESUMEN

Saccharides are a popular group of stabilizers in liquid, frozen and freeze dried protein formulations. The current work reviewed the stabilization mechanisms of three groups of saccharides: (i) Disaccharides, specifically sucrose and trehalose; (ii) cyclodextrins (CDs), a class of cyclic oligosaccharides; and (iii) dextrans, a class of polysaccharides. Compared to sucrose, trehalose exhibits a more pronounced preferential exclusion effect in liquid protein formulations, due to its stronger interaction with water molecules. However, trehalose obtains higher phase separation and crystallization propensity in frozen solutions, resulting in the loss of its stabilization function. In lyophilized formulations, sucrose has a higher crystallization propensity. Besides, its glass matrix is less homogeneous than that of trehalose, thus undermining its lyoprotectant function. Nevertheless, the hygroscopic nature of trehalose may result in high water absorption upon storage. Among all the CDs, the ß form is believed to have stronger interactions with proteins than the α- and γ-CDs. However, the stabilization effect, brought about by CD-protein interactions, is case-by-case - in some examples, such interactions can promote protein destabilization. The stabilization effect of hydroxypropyl-ß-cyclodextrin (HPßCD) has been extensively studied. Due to its amphiphilic nature, it can act as a surface-active agent in preventing interfacial stresses. Besides, it is a dual functional excipient in freeze dried formulations, acting as an amorphous bulking agent and lyoprotectant. Finally, dextrans, when combined with sucrose or trehalose, can be used to produce stable freeze dried protein formulations. A strong stabilization effect can be realized by low molecular weight dextrans. However, the terminal glucose in dextrans yields protein glycation, which warrants extra caution during formulation development.


Asunto(s)
Ciclodextrinas , Trehalosa , Trehalosa/química , Sacarosa/química , Ciclodextrinas/química , Dextranos/química , Excipientes/química , Agua/química , Liofilización
8.
Mol Pharm ; 20(12): 6380-6390, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-37947441

RESUMEN

Freezing is commonly encountered during the processing and storage of biomacromolecule products. Therefore, understanding the phase and state transitions in pharmaceutical frozen solutions is crucial for the rational development of biopharmaceuticals. Solid-state nuclear magnetic resonance spectroscopy (ssNMR) was used to analyze solutions containing sodium phosphate buffer, histidine, and trehalose. Upon freezing, crystallization of disodium phosphate hydrogen dodecahydrate (Na2HPO4·12H2O, DPDH) and histidine was identified using 31P and 13C ssNMR, respectively, and confirmed by synchrotron X-ray diffractometry (SXRD). Using histidine as a molecular probe and based on the chemical shifts of atoms of interest, the pH of the freeze concentrate was measured. The unfrozen water content in freeze concentrates was quantified by 1H single pulse experiments. 13C-insensitive nuclei enhancement by polarization transfer (INEPT) and cross-polarization (CP) experiments were used as orthogonal tools to characterize the solutes in a "mobile" and a more "solid-like" state in the freeze-concentrated solutions, respectively. The above analyses were applied to a commercial monoclonal antibody (mAb) formulation of dupilumab. This work further establishes ssNMR spectroscopy as a highly capable biophysical tool to investigate the attributes of biopharmaceuticals and thereby provide insights into process optimization and formulation development.


Asunto(s)
Productos Biológicos , Histidina , Congelación , Difracción de Rayos X , Soluciones , Espectroscopía de Resonancia Magnética , Liofilización
9.
Int J Pharm ; 648: 123555, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37890646

RESUMEN

As the advancements in the medical technology and healthcare develop through the years, combinational therapy has evolved to be an important treatment modality in many disease settings, including cancer, cardiovascular disease and infectious diseases. In an effort to alleviate "pill burden" and improve patient compliance, fixed dose combinations (FDCs) have been developed to be used as effective therapeutics. Among all FDCs, the category of drug-drug molecular complexes has been proven an efficient methodology in designing and treating diseases, with many drugs being approved. Among all drug-drug molecular complexes, drug-drug cocrystals, salts, coamorphous systems and solid dispersions have been successfully developed and many have been approved by the FDA. In this review, we dwell deeply into the molecular mechanisms behind the different types of drug-drug molecular complexes, including the key functional groups involved in the intermolecular interactions, the applications of each category of molecular complexes, as well as the advantages and challenges thereof. This comprehensive review provides useful insights into the practical design and manufacture of drug-drug molecular complexes and points out the future direction for the development of new advantageous combinational therapies that benefit more patients.


Asunto(s)
Sales (Química) , Humanos , Solubilidad , Combinación de Medicamentos
10.
Cell Death Dis ; 14(9): 628, 2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37739961

RESUMEN

Kidney diseases remain one of the leading causes of human death and have placed a heavy burden on the medical system. Regulated cell death contributes to the pathology of a plethora of renal diseases. Recently, with in-depth studies into kidney diseases and cell death, a new iron-dependent cell death modality, known as ferroptosis, has been identified and has attracted considerable attention among researchers in the pathogenesis of kidney diseases and therapeutics to treat them. The majority of studies suggest that ferroptosis plays an important role in the pathologies of multiple kidney diseases, such as acute kidney injury (AKI), chronic kidney disease, and renal cell carcinoma. In this review, we summarize recently identified regulatory molecular mechanisms of ferroptosis, discuss ferroptosis pathways and mechanisms of action in various kidney diseases, and describe the protective effect of ferroptosis inhibitors against kidney diseases, especially AKI. By summarizing the prominent roles of ferroptosis in different kidney diseases and the progress made in studying ferroptosis, we provide new directions and strategies for future research on kidney diseases. In summary, ferroptotic factors are potential targets for therapeutic intervention to alleviate different kidney diseases, and targeting them may lead to new treatments for patients with kidney diseases.


Asunto(s)
Lesión Renal Aguda , Ferroptosis , Neoplasias Renales , Muerte Celular Regulada , Humanos , Riñón , Lesión Renal Aguda/genética
11.
AAPS PharmSciTech ; 24(7): 175, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37603110

RESUMEN

Polymeric amorphous solid dispersion (ASD) is a popular approach for enhancing the solubility of poorly water-soluble drugs. However, achieving both physical stability and dissolution performance in an ASD prepared with a single polymer can be challenging. Therefore, a secondary excipient can be added. In this paper, we review three classes of additives that can be added internally to ASDs: (i) a second polymer, to form a ternary drug-polymer-polymer ASD, (ii) counterions, to facilitate in situ salt formation, and (iii) surfactants. In an ASD prepared with a combination of polymers, each polymer exerts a unique function, such as a stabilizer in the solid state and a crystallization inhibitor during dissolution. In situ salt formation in ASD usually leads to substantial increases in the glass transition temperature, contributing to improved physical stability. Surfactants can enhance the wettability of ASD particles, thereby promoting rapid drug release. However, their potential adverse effects on physical stability and dissolution, resulting from enhanced molecular mobility and competitive molecular interaction with the polymer, respectively, warrant careful consideration. Finally, we discuss the impact of magnesium stearate and inorganic salts, excipients added externally upon downstream processing, on the solid-state stability as well as the dissolution of ASD tablets.


Asunto(s)
Excipientes , Polímeros , Solubilidad , Cristalización , Liberación de Fármacos
12.
Mol Pharm ; 20(9): 4587-4596, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37535010

RESUMEN

The phase behavior of poloxamer 188 (P188) in aqueous solutions, characterized by differential scanning calorimetry (DSC) and synchrotron X-ray diffractometry, revealed solute crystallization during both freezing and thawing. Sucrose and trehalose inhibited P188 crystallization during freeze-thawing (FT). While trehalose inhibited P188 crystallization only during cooling, sucrose completely suppressed P188 crystallization during both cooling and heating. Lactate dehydrogenase (LDH) served as a model protein to evaluate the stabilizing effect of P188. The ability of P188, over a concentration range of 0.003-0.800% w/v, to prevent LDH (10 µg/mL) destabilization was evaluated. After five FT cycles, the aggregation behavior (by dynamic light scattering) and activity recovery were evaluated. While LDH alone was sensitive to interfacial stress, P188 at concentrations of ≥0.100% w/v stabilized the protein. However, as the surfactant concentration decreased, protein aggregation after FT increased. The addition of sugar (1.0% w/v; sucrose or trehalose) improved the stabilizing function of P188 at lower concentrations (≤0.010% w/v), possibly due to the inhibition of surfactant crystallization. Based on a comparison with the stabilization effect of polysorbate (both 20 and 80), it was evident that P188 could be a promising alternative surfactant in frozen protein formulations. However, when the surfactant concentration is low, the potential for P188 crystallization and the consequent compromise in its functionality warrant careful consideration.


Asunto(s)
Hielo , Poloxámero , Congelación , Trehalosa/química , Proteínas , L-Lactato Deshidrogenasa/química , Tensoactivos , Sacarosa/química , Liofilización , Rastreo Diferencial de Calorimetría
13.
Adv Mater ; 35(45): e2305535, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37607503

RESUMEN

The progress of solar-driven water-splitting technology has been impeded by the limited light response capability of semiconductor materials. Despite attempts to leverage nearly 50% of infrared radiation for photothermal synergy and catalytic reaction enhancement, heat loss during liquid phase reactions results in low energy conversion efficiency. Here, the photothermally driven catalytic water-splitting system, which designs K-SrTiO3 -loaded TiN silica wool at the water-air interface. Photocatalytic tests and density functional theory calculations demonstrate that the thermal effect transforms liquid water into water vapor, thereby reducing the reaction free energy of catalysts and improving the transmission rate of catalytic products. Hence, the hydrogen evolution rate reaches 275.46 mmol m-2  h-1 , and the solar-to-hydrogen (STH) efficiency is 1.81% under 1 sun irradiation in this gas-solid system, which is more than twice that of liquid water splitting. This novel photothermal catalytic pathway, which involves a coupled reaction of water evaporation and water splitting, is anticipated to broaden the utilization range of the solar spectrum and significantly enhance the conversion efficiency of STH.

14.
Cell Death Dis ; 14(7): 462, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37488117

RESUMEN

Multiple primary lung cancers (MPLCs) pose diagnostic and therapeutic challenges in clinic. Here, we orchestrated the cellular and spatial architecture of MPLCs by combining single-cell RNA-sequencing and spatial transcriptomics. Notably, we identified a previously undescribed sub-population of epithelial cells termed as CLDN2+ alveolar type II (AT2) which was specifically enriched in MPLCs. This subtype was observed to possess a relatively stationary state, play a critical role in cellular communication, aggregate spatially in tumor tissues, and dominate the malignant histopathological patterns. The CLDN2 protein expression can help distinguish MPLCs from intrapulmonary metastasis and solitary lung cancer. Moreover, a cell surface receptor-TNFRSF18/GITR was highly expressed in T cells of MPLCs, suggesting TNFRSF18 as one potential immunotherapeutic target in MPLCs. Meanwhile, high inter-lesion heterogeneity was observed in MPLCs. These findings will provide insights into diagnostic biomarkers and therapeutic targets and advance our understanding of the cellular and spatial architecture of MPLCs.


Asunto(s)
Neoplasias Pulmonares , Neoplasias Primarias Múltiples , Humanos , Células Epiteliales , Comunicación Celular , Perfilación de la Expresión Génica
15.
ACS Nano ; 17(12): 11616-11625, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37317581

RESUMEN

Most of the existing photocatalysts can only use ultraviolet light and part of visible light, so broadening the spectrum response range and realizing the full spectrum coverage are key measures to improve the solar-to-hydrogen (STH) efficiency of photocatalytic water splitting. A spatially separated photothermal coupled photocatalytic (PTC) reaction system was designed using carbonized melamine foam (C-MF) as a substrate to absorb visible and infrared light and Cu0.04In0.25ZnSy@Ru (CIZS@Ru) as a photocatalyst to absorb UV-visible light (UV-vis). By comparing the three modes of bottom, liquid level, and self-floating, it is found that the surface temperature of the system has a significant effect on the hydrogen evolution activity. The monochromatic light and activation energy experiments verify that the enhancement of photocatalytic activity comes from the strengthened photothermal effect of the substrate. Combined with theoretical calculations, it is further confirmed that the introduction of photothermal materials provides additional kinetic energy for carrier transmission and promotes directional carrier transmission efficiency. Based on the photoenergy-thermal integrated catalytic strategy, the hydrogen production rate reaches 603 mmol h-1 m-2. The structural design of photocatalysis has potential application in the field of photoenergy-fuel conversion.

16.
Front Oncol ; 13: 1232714, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37388225

RESUMEN

[This corrects the article DOI: 10.3389/fonc.2022.847805.].

17.
ISA Trans ; 139: 179-190, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37169694

RESUMEN

This article focuses on the reachable set estimation and the state-feedback controller design for switched linear systems with a state-dependent switching and event-triggered control. First, the event-triggered bumpless transfer performance is given. The reachable set of the switched system is estimated under the proposed bumpless transfer based event-triggered mechanism by using the multiple Lyapunov functions method. A co-design of the event-triggered mechanism, a switching law and the controller gain is provided. Second, Zeno behavior is avoided by showing the existence of a positive lower bound on the event triggered interexecution intervals. Third, we design a state-feedback controller which contains the system states in a preset ellipsoid. Finally, numerical examples are given to illustrate the effectiveness of the theoretical claims.

18.
Chemistry ; 29(38): e202300879, 2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37104095

RESUMEN

Inspired by carbon monoxide dehydrogenase (CODH), mimicking its inner and outer spheres is a promising strategy in CO2 reduction catalyst design. However, artificial CODH-like catalysts are generally limited to the inner sphere effect and only applicable in organic solvents or for electrocatalysis. Herein, an aqueous CODH mimic with both inner and outer spheres for photocatalysis is reported. In this polymeric unimolecular catalyst, the inner sphere is composed of cobalt porphyrin with four appended amido groups and the outer sphere consists of four poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) arms. Upon visible light irradiation (λ >420 nm), the as-prepared catalyst exhibits a turnover number (TONCO ) of 1731.2 in the reduction of CO2 into CO, which is comparable to most reported molecular catalysts in aqueous solution. The mechanism studies indicate that, in this water-dispersible and structurally well-defined CODH mimic, the cobalt porphyrin core serves as the catalysis center and the amido groups function as hydrogen-bonding pillars helping to stabilize the CO2 adduct intermediate, whereas the PDMAEMA shell renders both water solubility and a CO2 reservoir through reversibly capturing of CO2 . The present work has clarified the significance of coordination sphere effects for improving the aqueous photocatalytic CO2 reduction performance of CODH mimics.


Asunto(s)
Imitación Molecular , Soluciones , Catálisis , Oxidación-Reducción , Dióxido de Carbono/química , Micelas
19.
J Colloid Interface Sci ; 641: 239-250, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36933470

RESUMEN

As an attractive semiconductor photocatalyst, (CuInS2)x-(ZnS)y has been intensively studied in photocatalysis, due to its unique layered structure and stability. Here, we synthesized a series of CuxIn0.25ZnSy photocatalysts with different trace Cu+-dominated ratios. The results show that doping with Cu+ ions leads to an increase in the valence state of In and the formation of a distorted S structure, simultaneously inducing a decrease in the semiconductor bandgap. When the doping amount of Cu+ ions is 0.04 atomic ratio to Zn, the optimized Cu0.04In0.25ZnSy photocatalyst with a bandgap of 2.16 eV shows the highest catalytic hydrogen evolution activity (191.4 µmol.h-1). Subsequently, among the common cocatalysts, Rh loaded Cu0.04In0.25ZnSy gives the highest activity of 1189.8 µmol·h-1, corresponding to an apparent quantum efficiency of 49.11 % at 420 nm. Moreover, the internal mechanism of photogenerated carrier transfer between semiconductors and different cocatalysts is analyzed by the band bending phenomenon.

20.
Huan Jing Ke Xue ; 44(1): 531-539, 2023 Jan 08.
Artículo en Chino | MEDLINE | ID: mdl-36635841

RESUMEN

Biochar, as a soil amendment for synergizing the reduction of pollution and carbon emissions, shows great potential and future prospects in controlling antibiotic contamination. In order to research the effects of biochar on antibiotic behaviors in soil systematically, a Meta-analysis was conducted based on 20 studies published from 2011 to 2021. The results showed that the adsorption and degradation of antibiotics in the soil were significantly affected by the application rate and property of biochar. A 2% biochar application dose seemed to be the highest effect size (ES) of 0.19 on adsorption, while there was a significant effect (ES=0.23) on the degradation when the application rate was 5%. The specific surface area, polarity, stability, and aromaticity of biochar could increase the partition coefficient significantly, and the ES was 0.11, 0.13, 0.09, and 0.18, respectively, whereas the effects of antibiotic transport on the dose and property of biochar were insignificant. Biochar also indirectly controlled antibiotic behavior by altering the soil environment. However, the response of the coupling mechanism in antibiotic behaviors on biochar application into soil is still unclear. Moreover, the long-term and negative effects of biochar application in the field are still lacking basic data.


Asunto(s)
Antibacterianos , Suelo , Carbón Orgánico , Carbono
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