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1.
Environ Sci Technol ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989600

RESUMO

Transition-metal dichalcogenides (TMDs) have shown great promise as selective and high-capacity sorbents for Hg(II) removal from water. Yet, their design should consider safe disposal of spent materials, particularly the subsequent formation of methylmercury (MeHg), a highly potent and bioaccumulative neurotoxin. Here, we show that microbial methylation of mercury bound to MoS2 nanosheets (a representative TMD material) is significant under anoxic conditions commonly encountered in landfills. Notably, the methylation potential is highly dependent on the phase compositions of MoS2. MeHg production was higher for 1T MoS2, as mercury bound to this phase primarily exists as surface complexes that are available for ligand exchange. In comparison, mercury on 2H MoS2 occurs largely in the form of precipitates, particularly monovalent mercury minerals (e.g., Hg2MoO4 and Hg2SO4) that are minimally bioavailable. Thus, even though 1T MoS2 is more effective in Hg(II) removal from aqueous solution due to its higher adsorption affinity and reductive ability, it poses a higher risk of MeHg formation after landfill disposal. These findings highlight the critical role of nanoscale surfaces in enriching heavy metals and subsequently regulating their bioavailability and risks and shed light on the safe design of heavy metal sorbent materials through surface structural modulation.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38989704

RESUMO

Lithium (Li) metal batteries (LMBs) have garnered significant research attention due to their high energy density. However, uncontrolled Li dendrite growth and the continuous accumulation of "dead Li" directly lead to poor electrochemical performance in LMBs, along with serious safety hazards. These issues have severely hindered their commercialization. In this study, a lithiophilic layer of Sn-Cu2O is constructed on the surface of copper foam (CF) grown with Cu nanowire arrays (SCCF) through a combination of electrodeposition and plasma reduction. Sn-Cu2O, with excellent lithiophilicity, reduces the Li nucleation barrier and promotes uniform Li deposition. Simultaneously, the high surface area of the nanowires reduces the local current density, further suppressing the Li dendrite growth. Therefore, at 1 mA cm-2, the half cells and symmetric cells achieve high Coulombic efficiency (CE) and stable operation for over 410 cycles and run smoothly for more than 1350 h. The full cells using an LFP cathode demonstrate a capacity retention rate of 90.6% after 1000 cycles at 5 C, with a CE as high as 99.79%, suggesting excellent prospects for rapid charging and discharging and long-term cyclability. This study provides a strategy for modifying three-dimensional current collectors for Li metal anodes, offering insights into the construction of stable, safe, and fast-charging LMBs.

3.
ChemSusChem ; : e202401267, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989716

RESUMO

Metal-free carbon-based electrocatalysts have gained significant attention in the field of zinc-air batteries (ZABs) due to their affordability, good conductivity and chemical stability. However, unmodified carbon materials typically fall short in adsorbing and activating the substrates and intermediates involved in oxygen reduction reactions (ORR). Here, a metal-free carbon-based electrocatalyst with S atom p orbital hybrid modified N-sp3/sp2 carbon structure (C/NS) were prepared by cyclodextrins inclusion. The catalyst demonstrates impressive ORR activity (E1/2=0.885 V vs. RHE) and robust ZABs performance with a power density of 171.3 mW cm-2 and a specific capacity of 781.2 mAh g-1. Density functional theory (DFT) calculation reveals that S atom effectively regulates the charge distribution and p-band center of active site carbon atom in the N-sp3/sp2 carbon structure. This modification prompts the adsorption and dissociation of O2 and intermediates, resulting in higher reactive activity. This work provides a valuable and practical strategy for preparing cost-effective metal-free carbon-based electrocatalysts for ORR with high performance.

4.
Angew Chem Int Ed Engl ; : e202405681, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985847

RESUMO

Photocatalytic hydrogen production offers an alternative pathway to establish a sustainable energy economy. While numerous photoactive materials exhibit potential for generating hydrogen from water, the synergy achieved by combining two different materials with complementary properties in the form of heterojunctions can significantly their photocatalytic activity. Our study describes the design and generation of the metal-organic framework-derived (MOF) metal oxide heterojunction composed of RuO2/N,S-TiO2. The RuO2/N,S-TiO2 is generated through the pyrolysis of MOFs, Ru- HKUST-1, and the amino-functionalized MIL-125-NH2. Among the various RuO2/N,S- TiO2 materials tested, the material characterized by the lowest RuO2 content, exhibited the highest hydrogen evolution rate, producing 10,761 µmol·hr-1·g-1 of hydrogen with an apparent quantum-yield of 10.0% in pure water. In addition to RuO2/N,S-TiO2, we generated two other MOF-derived metal-oxide heterojunctions, ZnO/N,S-TiO2 and In2O3/N,S-TiO2, leading to apparent quantum yields of 0.7% and 0.3%, respectively. The remarkable photocatalytic activity observed in RuO2/N,S-TiO2 is thought to be attributed to the synergistic effects arising from the combination of metallic properties inherent in the metal oxides, their band alignment, porosity, and surface properties inherited from the parent MOFs. The photocatalytic efficiency of RuO2/N,S-TiO2 was further demonstrated in actual water samples, producing hydrogen with a rate of 8,190 µmol·hr-1·g-1 in tap water.

5.
Synthesis (Stuttg) ; 56(13): 1967-1978, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38962497

RESUMO

The absorption of light by photosensitizers has been shown to offer novel reactive pathways through electronic excited state intermediates, complementing ground state mechanisms. Such strategies have been applied in both photocatalysis and photoredox catalysis, driven by generating reactive intermediates from their long-lived excited states. One developing area is photoinduced ligand-to-metal charge transfer (LMCT) catalysis, in which coordination of a ligand to a metal center and subsequent excitation with light results in the formation of a reactive radical and a reduced metal center. This mini review concerns the foundations and recent developments in ligand-to-metal charge transfer in transition metal catalysis focusing on the organic transformations made possible through this mechanism.

6.
Curr Protoc ; 4(7): e1038, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38967962

RESUMO

A variety of metals, e.g., lead (Pb), cadmium (Cd), and lithium (Li), are in the environment and are toxic to humans. Hematopoietic stem cells (HSCs) reside at the apex of hematopoiesis and are capable of generating all kinds of blood cells and self-renew to maintain the HSC pool. HSCs are sensitive to environmental stimuli. Metals may influence the function of HSCs by directly acting on HSCs or indirectly by affecting the surrounding microenvironment for HSCs in the bone marrow (BM) or niche, including cellular and extracellular components. Investigating the impact of direct and/or indirect actions of metals on HSCs contributes to the understanding of immunological and hematopoietic toxicology of metals. Treatment of HSCs with metals ex vivo, and the ensuing HSC transplantation assays, are useful for evaluating the impacts of the direct actions of metals on the function of HSCs. Investigating the mechanisms involved, given the rarity of HSCs, methods that require large numbers of cells are not suitable for signal screening; however, flow cytometry is a useful tool for signal screening HSCs. After targeting signaling pathways, interventions ex vivo and HSCs transplantation are required to confirm the roles of the signaling pathways in regulating the function of HSCs exposed to metals. Here, we describe protocols to evaluate the mechanisms of direct and indirect action of metals on HSCs. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Identify the impact of a metal on the competence of HSCs Basic Protocol 2: Identify the impact of a metal on the lineage bias of HSC differentiation Basic Protocol 3: Screen the potential signaling molecules in HSCs during metal exposure Alternate Protocol 1: Ex vivo treatment with a metal on purified HSCs Alternate Protocol 2: Ex vivo intervention of the signaling pathway regulating the function of HSCs during metal exposure.


Assuntos
Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/citologia , Animais , Metais/toxicidade , Camundongos , Humanos , Transplante de Células-Tronco Hematopoéticas , Citometria de Fluxo/métodos
7.
Mikrochim Acta ; 191(8): 449, 2024 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967877

RESUMO

A family of inorganic-organic hybrid crystalline materials made up of organic ligands and metal cations or clusters is known as metal-organic frameworks (MOFs). Because of their unique stability, intriguing characteristics, and structural diversity, zirconium-based MOFs (Zr-MOFs) are regarded as one of the most interesting families of MOF materials for real-world applications. Zr-MOFs that have the ligands, metal nodes, and guest molecules enclosed show distinct electrochemical reactions. They can successfully and sensitively identify a wide range of substances, which is important for both environmental preservation and human health. The rational design and synthesis of Zr-MOF electrochemical sensors and biosensors, as well as their applications in the detection of drugs, biomarkers, pesticides, food additives, hydrogen peroxide, and other materials, are the main topics of this comprehensive review. We also touch on the current issues and potential future paths for Zr-MOF electrochemical sensor research.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Estruturas Metalorgânicas , Zircônio , Zircônio/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Estruturas Metalorgânicas/química , Humanos
8.
Proc Natl Acad Sci U S A ; 121(28): e2401579121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38968123

RESUMO

Iron is an essential element for life owing to its ability to participate in a diverse array of oxidation-reduction reactions. However, misregulation of iron-dependent redox cycling can also produce oxidative stress, contributing to cell growth, proliferation, and death pathways underlying aging, cancer, neurodegeneration, and metabolic diseases. Fluorescent probes that selectively monitor loosely bound Fe(II) ions, termed the labile iron pool, are potentially powerful tools for studies of this metal nutrient; however, the dynamic spatiotemporal nature and potent fluorescence quenching capacity of these bioavailable metal stores pose challenges for their detection. Here, we report a tandem activity-based sensing and labeling strategy that enables imaging of labile iron pools in live cells through enhancement in cellular retention. Iron green-1 fluoromethyl (IG1-FM) reacts selectively with Fe(II) using an endoperoxide trigger to release a quinone methide dye for subsequent attachment to proximal biological nucleophiles, providing a permanent fluorescent stain at sites of elevated labile iron. IG1-FM imaging reveals that degradation of the major iron storage protein ferritin through ferritinophagy expands the labile iron pool, while activation of nuclear factor-erythroid 2-related factor 2 (NRF2) antioxidant response elements (AREs) depletes it. We further show that lung cancer cells with heightened NRF2 activation, and thus lower basal labile iron, have reduced viability when treated with an iron chelator. By connecting labile iron pools and NRF2-ARE activity to a druggable metal-dependent vulnerability in cancer, this work provides a starting point for broader investigations into the roles of transition metal and antioxidant signaling pathways in health and disease.


Assuntos
Elementos de Resposta Antioxidante , Ferro , Humanos , Ferro/metabolismo , Corantes Fluorescentes/química , Fator 2 Relacionado a NF-E2/metabolismo , Ferritinas/metabolismo , Estresse Oxidativo , Oxirredução , Linhagem Celular Tumoral , Antioxidantes/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-38968249

RESUMO

Transition metal dichalcogenides (TMDs) have garnered significant attention as efficient electrocatalysts for the hydrogen evolution reaction (HER) due to their high activity, stability, and cost-effectiveness. However, the development of a convenient and economical approach for large-scale HER applications remains a persistent challenge. In this study, we present the successful synthesis of TMD nanoparticles (including MoS2, RuS2, ReS2, MoSe2, RuSe2, and ReSe2) using a general colloidal method at room temperature. Notably, the ReSe2 nanoparticles synthesized in this study exhibit superior HER performance compared with previously reported nanostructured TMDs. Importantly, the synthesis of these TMD nanoparticles can readily be scaled up to gram quantities while preserving their exceptional HER performance. These findings highlight the potential of colloidal synthesis as a versatile and scalable approach for producing TMD nanomaterials with outstanding electrocatalytic properties for water splitting.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38968444

RESUMO

A metal-insulator-semiconductor (MIS) structure holds great potential to promote photoelectrochemical (PEC) reactions, such as water splitting and CO2 reduction, for the storage of solar energy in chemical bonds. The semiconductor absorbs photons, creating electron-hole pairs; the insulator facilitates charge separation; and the metal collects the desired charge and facilitates its use in the electrochemical reaction. Despite these attractive features, MIS photoelectrodes are significantly limited by their photovoltage, a combination of the voltage generated from photon absorption minus the potential drop across the insulator. Herein, we use multiscale continuum modeling of the carrier, electrolyte, and interfacial transport to identify strategies for mitigating the deleterious potential drop across the insulator and enabling high MIS photovoltages. To this end, we model Ni/SiO2/n-Si photoanodes that employ a planar Ni film or Ni nanoparticles (np-MIS) and validate both models using experimental polarization curves and photovoltage measurements from the literature. The simulations reveal that the insulator potential drop is lower and hence achieves higher photovoltages for np-MIS structures than MIS structures because the electrolyte screens charge trapped at defect states between the semiconductor and the insulator. This electrolyte charge screening phenomenon can be further leveraged by using low loadings or small nanoparticles, which not only minimize the interfacial potential drop but also improve the photocurrent by enabling more light absorption. These insights contribute to the optimization of the np-MIS structures for sustainable energy conversion.

11.
J Colloid Interface Sci ; 675: 104-116, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38968631

RESUMO

Exploring precious metal-free bifunctional electrocatalysts for both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) is essential for the practical application of rechargeable Zn-air battery (ZAB). Herein, Ni-doped Co9S8 nanoparticles embedded in a defect-rich N, S co-doped carbon matrix (d-NixCo9-xS8@NSC) are synthesized via a facile pyrolysis and acid treatment process. The introduction of abundant defects in both the carbon matrix and metal sulfide provides numerous active sites and significantly enhances the electrocatalytic performances for both the ORR and OER. d-NixCo9-xS8@NSC exhibits a superior half-wave potential of 0.841 V vs. RHE for the ORR and delivers a low overpotential of 0.329 V at 10 mA cm-2 for the OER. Additionally, Zn-air secondary battery using d-NixCo9-xS8@NSC as the air cathode displays a higher specific capacity of 734 mAh gZn-1 and a peak power density of 148.03 mW cm-2 compared to those of state-of-the-art Pt/C-RuO2 (673 mAh gZn-1 and 136.9 mW cm-2, respectively). These findings underscore the potential of d-NixCo9-xS8@NSC as a high-performance electrocatalyst for secondary ZABs, offering new perspectives on the design of efficient noble metal-free electrocatalysts for future energy storage and conversion applications.

12.
J Colloid Interface Sci ; 675: 139-149, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38968634

RESUMO

Transition metal selenides (TMS) have received much attention as anode materials for sodium-ion batteries (SIBs) because of their high theoretical capacity and excellent redox reversibility. However, their further development is constrained by the dissolution of transition metal ions and substantial volume changes experienced during cycling. Herein, the high-entropy Prussian blue analogues were selenized by the vapor infiltration method, resulting in the formation of a core-shell structured high-entropy selenides (HESe-6). The core-shell structure with voids and abundant selenium vacancies on the surface effectively mitigates bulk expansion and enhances electronic conductivity. Furthermore, the high-entropy property endows an ultra-stable crystal structure and inhibits the dissolution of metal ions. The ex-situ EIS and in-situ XRD results show that HESe-6 is able to be reversibly transformed into highly conductive ultrafine metal particles upon Na+ embedding, providing more Na+ reactive active sites. In addition, despite the incorporation of up to seven different elements, it exhibits minimal phase transitions during discharge/charge cycles, effectively mitigating stress accumulation. HESe-6 could retain an ultralong-term stability of 765.83 mAh g-1 after 1000 loops even at 1 A g-1. Furthermore, when coupled with the Na3V2(PO4)2O2F cathode, it maintains a satisfactory charge energy density of 303 Wh kg-1 after 300 cycles, which shows promising application prospect in the future.

13.
J Colloid Interface Sci ; 675: 94-103, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38968640

RESUMO

To enhance the economic viability of photocatalytic materials for carbon capture and conversion, the challenge of employing expensive photosensitizer must be overcome. This study aims to improve the visible light utilization with zirconium-based metal-organic frameworks (Zr-MOFs) by employing a multi-component post-synthetic modification (PSM) strategy. An economical photosensitiser and copper ions are introduced into MOF 808 to enhance its photoreduction properties. Notably, the PSM of MOF 808 shows the highest CO yield up to 236.5 µmol g-1 h-1 with aHCOOH production of 993.6 µmol g-1 h-1 under non-noble metal, and its mechanistic insight for CO2 reaction is discussed in detail. The research results have important reference value for the potential application of photocatalytic metal-organic frameworks.

14.
Food Chem ; 458: 140306, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38968710

RESUMO

This study focused on detecting streptomycin (STR) residues using a luminescent aptasensor encapsulated with aptamer. Utilizing MOF-74-Co with peroxidase-like activity, luminol was enclosed in its pores. The specific STR aptamer acted as a gatekeeper, ensuring excellent performance. Upon exposure to STR, the aptamers detached, releasing luminol and amplifying the luminescent signal through MOF-74-Co catalytic activity. A linear relationship between fluorescence intensity and STR concentration (50 nM âˆ¼ 5 × 106 nM) was established, with a limit of detection of 0.065 nM. The sensor exhibited high selectivity for STR even in the presence of other aminoglycoside antibiotics. Applied to tea, egg, and honey samples, the sensor showed recovery rates of 91.38-100.2%, meeting safety standards. This MOF-based aptasensor shows promise for detecting harmful residues.

15.
Int J Hyg Environ Health ; 261: 114417, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38968837

RESUMO

BACKGROUND: Epidemiological studies on heavy metal exposure and liver injury are predominantly cross-sectional, lacking longitudinal data and exploration of potential mechanisms. METHOD: We conducted a repeated-measures study in Northeast China from 2016 to 2019, involving 322 participants. Linear mixed models (LMM) and Bayesian kernel machine regression (BKMR) were employed to explore the associations between individual and mixed blood metal concentrations [chromium (Cr), cadmium (Cd), vanadium (V), manganese (Mn), lead (Pb)] and liver function biomarkers [alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin (ALB), globulin (GLB), total protein (TP)]. Mediation and enrichment analyses were used to determine whether the inflammatory response is a critical pathway for heavy metal-induced liver damage. RESULT: We obtained a total of 958 observations. The results from LMM and BKMR indicated significant associations between individual and mixed heavy metals and liver function biomarkers. Longitudinal analysis revealed associations between Cd and the annual increase rate of ALT (ß = 2.61; 95% CI: 0.97, 4.26), the annual decrease rate of ALB (ß = -0.21; 95% CI: -0.39, -0.03), Mn and the annual increase rate of GLB (ß = 0.38; 95% CI: 0.05, 0.72), and V and the annual decrease rate of ALB/GLB (ß = -1.15; 95% CI: -2.00, -0.31). Mediation analysis showed that high-sensitivity C-reactive protein (hsCRP) mediated the associations between Cd and AST, TP, with mediation effects of 27.7% and 13.4%, respectively. Additionally, results from Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses supported the role of inflammatory response pathways. CONCLUSION: Our findings indicate that heavy metal exposure leads to liver damage, with the inflammatory response potentially serving as a crucial pathway in this process. This study offers a novel perspective on understanding heavy metal-induced liver injury and provides insights for preventive measures against the health damage caused by heavy metals.

16.
Environ Pollut ; : 124509, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38968981

RESUMO

The impact of environmental risk factors on chronic kidney disease (CKD) remains unclear. This systematic review aims to provide an overview of the literature on the association between the general external exposome and CKD development or progression. We searched MEDLINE and EMBASE for case-control or cohort studies, that investigated the association of the general external exposome with a change in eGFR or albuminuria, diagnosis or progression of CKD, or CKD-related mortality. The risk of bias of included studies was assessed using the Newcastle-Ottawa Scale. Summary effect estimates were calculated using random-effects meta-analyses. Most of the 66 included studies focused on air pollution (n=33), e.g. particulate matter (PM) and nitric oxides (NOx), and heavy metals (n=21) e.g. lead and cadmium. Few studies investigated chemicals (n=7) or built environmental factors (n=5). No articles on other environment factors such as noise, food supply, or urbanization were found. PM2.5 exposure was associated with an increased CKD and end-stage kidney disease incidence, but not with CKD-related mortality. There was mixed evidence regarding the association of NO2 and PM10 on CKD incidence. Exposure to heavy metals might be associated with an increased risk of adverse kidney outcomes, however, evidence was inconsistent. Studies on effects of chemicals or built environment on kidney outcomes were inconclusive. In conclusion, prolonged exposure to PM2.5 is associated with an increased risk of CKD incidence and progression to kidney failure. Current studies predominantly investigate the exposure to air pollution and heavy metals, whereas chemicals and the built environment remains understudied. Substantial heterogeneity and mixed evidence were found across studies. Therefore, long-term high-quality studies are needed to elucidate the impact of exposure to chemicals or other (built) environmental factors and CKD.

17.
Sci Total Environ ; : 174451, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969124

RESUMO

The combined contamination of terrestrial environments by metal(loid)s (MEs) and microplastics (MPs) is a major environmental issue. Once MPs enter soils, they can interact with MEs and modify their environmental availability, environmental bioavailability, and potential toxic effects on biota. Although research efforts have been made to describe the underlying mechanisms driving MP and ME interactions, the effects of MPs on ME bioavailability in terrestrial Mollusca have not yet been documented. To fill this gap, we exposed the terrestrial snail Cantareus aspersus to different combinations of polystyrene (PS) and arsenic (As), cadmium (Cd), or mercury (Hg) concentrations. Using kinetic approaches, we then assessed the variations in the environmental availability of As, Cd or Hg after three weeks of equilibration and in the environmental bioavailability of As, Cd or Hg to snails after four weeks of exposure. We showed that while environmental availability was influenced by the total ME concentration, the effects of PS were limited. Although an increase in As availability was observed for the highest exposure concentrations at the beginning of the experiment, the soil ageing processes led to rapid adsorption in the soil regardless of the PS particle concentration. Concerning transfers to snail, ME bioaccumulation was ME concentration-dependent but not modified by the PS concentration in the soils. Nevertheless, the kinetic approaches evidenced an increase in As (2- to 2.6-fold) and Cd (1.6-fold), but not Hg, environmental bioavailability or excretion (2.3- to 3.6-fold for As, 1.8-fold for Cd) at low PS concentrations. However, these impacts were no longer observable at the highest PS exposure concentrations because of the increase in the bioaccessibility of MEs in the snail digestive tract. The generalization of such hormetic responses and the identification of the precise mechanisms involved necessitate further research to deepen our understanding of the MP-mediated behaviour of MEs in co-occurring scenarios.

18.
Biochim Biophys Acta Biomembr ; : 184369, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969203

RESUMO

Trk1 is the main K+ importer of Saccharomyces cerevisiae. Its proper functioning enables yeast cells to grow in environments with micromolar amounts of K+. Although the structure of Trk1 has not been experimentally determined, the transporter is predicted to be composed of four MPM (transmembrane segment - pore loop - transmembrane segment) motifs which are connected by intracellular loops. Of those, in particular the first loop (IL1) is unique in its length; it forms more than half of the entire protein. The deletion of the majority of IL1 does not abolish the transport activity of Trk1. However IL1 is thought to be involved in the modulation of the transporter's functioning. In this work, we prepared a series of internally shortened versions of Trk1 that lacked various parts of IL1, and we studied their properties in S. cerevisiae cells without chromosomal copies of TRK genes. Using this approach, we were able to determine that both N- and C-border regions of IL1 are necessary for the proper localization of Trk1. Moreover, the N-border part of IL1 is also important for the functioning of Trk1, as its absence resulted in a decrease in the transporter's substrate affinity. In addition, in the internal part of IL1, we newly identified a stretch of amino-acid residues that are indispensable for retaining the transporter's maximum velocity, and another region whose deletion affected the ability of Trk1 to adjust its affinity in response to external levels of K+.

19.
Chemosphere ; : 142759, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969218

RESUMO

Currently, the use of natural adsorbent for the elimination of pollutants, such as heavy metals, from water has been extensively investigated. However, the low adsorption capacity of these natural adsorbent has led researchers towards the use of synthetic surfactants, which can themselves be environmental pollutants. In this research, an investigation was conducted to examine the impact of a surfactant obtained from the Seidlitzia rosmarinus plant on the adsorption properties of Pumpkin seed shell (PSS), a natural adsorbent. As a result, a modified version of PSS, known as Functionalized Pumpkin seed shell (FPSS), was developed, and the effect of these two adsorbents on the elimination of Pb2+ has been investigated. FESEM, EDS, FTIR, and BET analyses were conducted to get detailed information of the adsorbent. Additionally, the effects of contact time, dosage of the adsorbent, pH of the solution, and temperature on the adsorbent were studied. The experimental data was fitted using Langmuir, Freundlich, Temkin, and Jovanovic isotherms. The PSS adsorbent was fitted with the Temkin isotherm, showing an adsorption capacity of 160.80 mg g-1, while the FPSS adsorbent was fitted with the Jovanovic isotherm, exhibiting an adsorption capacity of 553.57 mg g-1. Furthermore, kinetic modeling results indicated that the data for these adsorbents follow pseudo-second-order kinetics. Finally, the impact of coexisting ions and reusability was examined, with the FPSS adsorbent outperforming PSS. Therefore, the investigation of all these aspects demonstrated that the use of this natural surfactant significantly improves the performance of the adsorbent.

20.
Environ Res ; : 119544, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969312

RESUMO

The main aim of this review is to provide an extensive summary of the latest advances within the emerging research area focused on detecting heavy metal ion pollution, particularly sensing strategies. The review explores various heavy metal ion detection approaches, encompassing spectrometry, electrochemical methods, and optical techniques. Numerous initiatives have been undertaken in recent times in response to the increasing demand for fast, sensitive, and selective sensors. Notably, fluorescent sensors have acquired prominence owing to the numerous advantages such as outstanding specificity, reversibility, and sensitivity. Further, it also explores the discussion of various nanomaterials employed in sensing heavy metal ions. In this regard, the exclusive emphasis is placed on fluorescent nanomaterials based on organic dyes, quantum dots, and fluorescent aptasensors for metal ion removal from aqueous systems to identify the destiny of dangerous heavy metal ions in clean circumstances.

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