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1.
Luminescence ; 39(5): e4768, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38719590

RESUMO

In this study, we synthesize nanostructured nickel oxide (NiO) and doped cobalt (Co) by combining nickel(II) chloride hexahydrate (NiCl2.6H2O) and sodium hydroxide (NaOH) as initial substances. We analyzed the characteristics of the product nanostructures, including their structure, optical properties, and magnetic properties, using various techniques such as x-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet absorption spectroscopy (UV-Vis), Fourier transform infrared (FTIR) spectroscopy, and vibrating sample magnetometers (VSM). The NiO nanoparticles doped with Co showed photocatalytic activity in degrading methylene blue (MB) dye in aqueous solutions. We calculated the degradation efficiencies by analyzing the UV-Vis absorption spectra at the dye's absorption wavelength of 664 nm. It was observed that the NiO-doped Co nanoparticles facilitated enhanced recombination and migration of active elements, which led to more effective degradation of organic dyes during photocatalysis. We also assessed the electrochemical properties of the materials using cyclic voltammetry (CV) and impedance spectroscopy in a 1 mol% NaOH solution. The NiO-modified electrode exhibited poor voltammogram performance due to insufficient contact between nanoparticles and the electrolyte solution. In contrast, the uncapped NiO's oxidation and reduction cyclic voltammograms displayed redox peaks at 0.36 and 0.30 V, respectively.


Assuntos
Cobalto , Eletroquímica , Eletrodos , Nanocompostos , Níquel , Nanocompostos/química , Níquel/química , Cobalto/química , Difração de Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Luminescência , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Fenômenos Magnéticos , Nanopartículas/química , Luz , Catálise , Óxidos/química , Azul de Metileno/metabolismo
2.
Anal Chim Acta ; 1307: 342627, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719406

RESUMO

BACKGROUND: Hydrogen peroxide (H2O2) is an important reactive oxygen species (ROS) molecule involved in cell metabolism regulation, transcriptional regulation, and cytoskeleton remodeling. Real-time monitoring of H2O2 levels in live cells is of great significance for disease prevention and diagnosis. RESULTS: We utilized carbon cloth (CC) as the substrate material and employed a single-atom catalysis strategy to prepare a flexible self-supported sensing platform for the real-time detection of H2O2 secreted by live cells. By adjusting the coordination structure of single-atom sites through P and S doping, a cobalt single-atom nanoenzyme Co-NC/PS with excellent peroxidase-like activity was obtained. Furthermore, we explored the enzyme kinetics and possible catalytic mechanism of Co-NC/PS. Due to the excellent flexibility, high conductivity, strong adsorption performance of carbon cloth, and the introduction of non-metallic atom-doped active sites, the developed Co-NC/PS@CC exhibited ideal sensing performance. Experimental results showed that the linear response range for H2O2 was 1-17328 µM, with a detection limit (LOD) of 0.1687 µM. Additionally, the sensor demonstrated good reproducibility, repeatability, anti-interference, and stability. SIGNIFICANCE: The Co-NC/PS@CC prepared in this study has been successfully applied for detecting H2O2 secreted by MCF-7 live cells, expanding the application of single-atom nanoenzymes in live cell biosensing, with significant implications for health monitoring and clinical diagnostics.


Assuntos
Cobalto , Técnicas Eletroquímicas , Peróxido de Hidrogênio , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Cobalto/química , Humanos , Técnicas Eletroquímicas/métodos , Células MCF-7 , Carbono/química , Limite de Detecção , Técnicas Biossensoriais/métodos
3.
Sci Rep ; 14(1): 10032, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693156

RESUMO

The primary objective of the present study was to produce metal complexes of H4DAP ligand (N,N'-((pyridine-2,6-diylbis(azanediyl))bis(carbonothioyl))dibenzamide) derived from 2,6-diaminopyridine and benzoyl isothiocyanate with either ML or M2L stoichiometry. There are three distinct coordination complexes obtained with the formulas [Co(H2DAP)]·H2O, [Ni2(H2DAP)Cl2(H2O)2]·H2O, and [Cu(H4DAP)Cl2]·3H2O. The confirmation of the structures of all derivatives was achieved through the utilization of several analytical techniques, including FT-IR, UV-Vis, NMR, GC-MS, PXRD, SEM, TEM analysis, and QM calculations. Aiming to analyze various noncovalent interactions, topological methods such as QTAIM, NCI, ELF, and LOL were performed. Furthermore, the capacity of metal-ligand binding was examined by fluorescence emission spectroscopy. An in vitro investigation showed that the viability of MDA-MB-231 and HepG-2 cells was lower when exposed to the manufactured Cu2+ complex, in comparison to the normal cis-platin medication. The compounds were further evaluated for their in vitro antibacterial activity. The Ni2+ complex has shown promising activity against all tested pathogens, comparable to the reference drugs Gentamycin and Ketoconazole. Furthermore, a computational docking investigation was conducted to further examine the orientation, interaction, and conformation of the recently created compounds on the active site of the Bcl-2 protein.


Assuntos
Cobalto , Complexos de Coordenação , Cobre , Isotiocianatos , Simulação de Acoplamento Molecular , Níquel , Níquel/química , Cobre/química , Humanos , Isotiocianatos/química , Isotiocianatos/farmacologia , Ligantes , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Cobalto/química , Linhagem Celular Tumoral , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química
4.
Ren Fail ; 46(1): 2347446, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38695335

RESUMO

This study is intended to explore the effect of hypoxia-inducible factor-1α (HIF-1α) activation on lipid accumulation in the diabetic kidney. A type 1 diabetic rat model was established by STZ intraperitoneal injection. Cobalt chloride (CoCl2) and YC-1 were used as the HIF-1α activator and antagonist, respectively. CoCl2 treatment significantly increased HIF-1α expression, accelerated lipid deposition, and accelerated tubular injury in diabetic kidneys. In vitro, CoCl2 effectively stabilized HIF-1α and increased its transportation from the cytoplasm to the nucleus, which was accompanied by significantly increased lipid accumulation in HK-2 cells. Furthermore, results obtained in vivo showed that HIF-1α protein expression in the renal tubules of diabetic rats was significantly downregulated by YC-1 treatment. Meanwhile, lipid accumulation in the tubules of the DM + YC-1 group was markedly decreased in comparison to the DM + DMSO group. Accordingly, PAS staining revealed that the pathological injury caused to the tubular epithelial cells was alleviated by YC-1 treatment. Furthermore, the blood glucose level, urine albumin creatinine ratio, and NAG creatinine ratio in the DM + YC-1 group were significantly decreased compared to the DM + DMSO group. Moreover, the protein expression levels of transforming growth factor ß1 (TGF-ß1) and connective tissue growth factor (CTGF) in diabetic kidneys were decreased by YC-1 treatment. Our findings demonstrate that the activation of HIF-1α contributed to interstitial injury in a rat model of diabetic nephropathy and that the underlying mechanism involved the induction of lipid accumulation.


Assuntos
Cobalto , Diabetes Mellitus Experimental , Nefropatias Diabéticas , Subunidade alfa do Fator 1 Induzível por Hipóxia , Animais , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ratos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Masculino , Ratos Sprague-Dawley , Túbulos Renais/patologia , Túbulos Renais/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Indazóis/farmacologia , Humanos , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Linhagem Celular
5.
Nefrologia (Engl Ed) ; 44(2): 180-193, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38697696

RESUMO

BACKGROUND: Contrast agents can directly or indirectly induce renal tubular ischemia and hypoxic damage. Given that cobalt chloride (CoCl2) can protect renal tubules, the protective effect and potential mechanism of action of CoCl2 on contrast-induced nephropathy (CIN) warrant investigation. METHODS: A CIN mouse model was established to determine the protective effect of CoCl2 on renal injury in vivo. Then, TMT-based proteomics was performed to determine the differentially expressed proteins (DEPs), following which, enrichment analyses of gene ontology and the KEGG pathway were performed. In vitro, a CIN model was constructed with renal tubular epithelial cells (HK-2) to determine the effect of CoCl2 on potential targets and the role of the key protein identified from the in vivo experiments. RESULTS: CoCl2 treatment decreased the levels of BUN and serum creatinine (sCr), while increasing the levels of urea and creatinine (Cr) in the urine of mice after CIN injury. Damage to the renal tubules in the CoCl2 treatment group was significantly less than in the CIN model group. We identified 79 DEPs after treating the in vivo model with CoCl2, and frequently observed ferroptosis-related GO and KEGG pathway terms. Of these, Hp (haptoglobin) was selected and found to have a strong renoprotective effect, even though its expression level in kidney tissue decreased after CoCl2 treatment. In HK-2 cells, overexpression of Hp reduced the ferroptosis caused by erastin, while knocking down Hp negated the attenuation effect of CoCl2 on HK-2 cell ferroptosis. CONCLUSION: CoCl2 attenuated kidney damage in the CIN model, and this effect was associated with the decrease in ferroptosis mediated by Hp.


Assuntos
Cobalto , Meios de Contraste , Ferroptose , Ferroptose/efeitos dos fármacos , Animais , Camundongos , Meios de Contraste/efeitos adversos , Masculino , Nefropatias/induzido quimicamente , Nefropatias/prevenção & controle , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Humanos , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/patologia
6.
ACS Biomater Sci Eng ; 10(5): 2880-2893, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38630940

RESUMO

Cobalt-chromium-molybdenum (CoCrMo) alloys are common wear-exposed biomedical alloys and are manufactured in multiple ways, increasingly using additive manufacturing processes such as laser powder bed fusion (LPBF). Here, we investigate the effect of proteins and the manufacturing process (wrought vs LPBF) and building orientation (LPBF-XY and XZ) on the corrosion, metal release, tribocorrosion, and surface oxide composition by means of electrochemical, mechanical, microscopic, diffractive, and spectroscopic methods. The study was conducted at pH 7.3 in 5 g/L NaCl and 5 mM 2-(N-morpholino) ethanesulfonic acid (MES) buffer, which was found to be necessary to avoid metal phosphate and metal-protein aggregate precipitation. The effect of 10 g/L bovine serum albumin (BSA) and 2.5 g/L fibrinogen (Fbn) was studied. BSA and Fbn strongly enhanced the release of Co, Cr, and Mo and slightly enhanced the corrosion (still in the passive domain) for all CoCrMo alloys and most for LPBF-XZ, followed by LPBF-XY and the wrought CoCrMo. BSA and Fbn, most pronounced when combined, significantly decreased the coefficient of friction due to lubrication, the wear track width and severity of the wear mechanism, and the tribocorrosion for all alloys, with no clear effect of the manufacturing type. The wear track area was significantly more oxidized than the area outside of the wear track. In the reference solution without proteins, a strong Mo oxidation in the wear track surface oxide was indicative of a pH decrease and cell separation of the anodic and cathodic areas. This effect was absent in the presence of the proteins.


Assuntos
Lasers , Soroalbumina Bovina , Corrosão , Soroalbumina Bovina/química , Bovinos , Animais , Pós , Fibrinogênio/química , Teste de Materiais , Cobalto/química , Propriedades de Superfície , Cromo/química , Vitálio/química
7.
J Hazard Mater ; 471: 134309, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38653133

RESUMO

This study addresses antibiotic pollution in global water bodies by integrating machine learning and optimization algorithms to develop a novel reverse synthesis strategy for inorganic catalysts. We meticulously analyzed data from 96 studies, ensuring quality through preprocessing steps. Employing the AdaBoost model, we achieved 90.57% accuracy in classification and an R²value of 0.93 in regression, showcasing strong predictive power. A key innovation is the Sparrow Search Algorithm (SSA), which optimizes catalyst selection and experimental setup tailored to specific antibiotics. Empirical experiments validated SSA's efficacy, with degradation rates of 94% for Levofloxacin and 97% for Norfloxacin, aligning closely with predictions within a 2% margin of error. This research advances theoretical understanding and offers practical applications in material science and environmental engineering, significantly enhancing catalyst design efficiency and accuracy through the fusion of advanced machine learning techniques and optimization algorithms.


Assuntos
Antibacterianos , Cobalto , Aprendizado de Máquina , Óxidos , Poluentes Químicos da Água , Cobalto/química , Catálise , Antibacterianos/química , Poluentes Químicos da Água/química , Óxidos/química , Levofloxacino/química , Norfloxacino/química , Algoritmos
8.
J Inorg Biochem ; 256: 112552, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38608554

RESUMO

In this work, we report the generation and characterization of two new Co(III)-peroxo complexes 2 and 3. 2 is best described as a mononuclear CoIII-(O2) complex that exhibits an 18O-isotope sensitive OO bond stretching vibration at 845(-49) cm-1, indicating a relatively weak peroxo moiety compared to those of other CoIII-(O2) complexes reported previously. Complex 3 is a CoIII-peroxo-arylboronate species having a rare {CoIIIOOBO} five-membered metallocycle, which is structurally characterized using X-ray crystallography. Investigations of the reaction mechanism using density functional theory calculations show that 2 likely undergoes a nucleophilic attack to an arylboronic acid, which is generated by hydrolysis of the BPh4- anion in wet acetonitrile solution, to first form a CoIII-peroxo-arylboronic acid adduct, followed by the loss of one benzene molecule to generate the five-membered metallocycle. The entire reaction is thermodynamically favorable. Taken together, the conversion of 2 to 3 represents the discovery of a novel nucleophilic reactivity that can be carried out by mononuclear Co(III)-peroxo complexes.


Assuntos
Ácidos Borônicos , Cobalto , Complexos de Coordenação , Ácidos Borônicos/química , Cobalto/química , Complexos de Coordenação/química , Cristalografia por Raios X , Estrutura Molecular
9.
J Colloid Interface Sci ; 667: 91-100, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38621335

RESUMO

The development of efficient and multifunctional sonosensitizers is crucial for enhancing the efficacy of sonodynamic therapy (SDT). Herein, we have successfully constructed a CoOx-loaded amorphous metal-organic framework (MOF) UIO-66 (A-UIO-66-CoOx) sonosensitizer with excellent catalase (CAT)- and glutathione-oxidase (GSH-OXD)-like activities. The A-UIO-66-CoOx exhibits a 2.6-fold increase in singlet oxygen (1O2) generation under ultrasound (US) exposure compared to crystalline UIO-66 sonosensitizer, which is attributed to its superior charge transfer efficiency and consistent oxygen (O2) supply. Additionally, the A-UIO-66-CoOx composite reduces the expression of glutathione peroxidase (GPX4) by depleting glutathione (GSH) through Co3+ and Co2+ valence changes. The high levels of highly cytotoxic 1O2 and deactivation of GPX4 can lead to lethal lipid peroxidation, resulting in concurrent apoptosis and ferroptosis. Both in vitro and vivo tumor models comprehensively confirmed the enhanced SDT antitumor effect using A-UIO-66-CoOx sonosensitizer. Overall, this study emphasizes the possibility of utilizing amorphization engineering to improve the effectiveness of MOFs-based sonosensitizers for combined cancer therapies.


Assuntos
Apoptose , Ferroptose , Estruturas Metalorgânicas , Terapia por Ultrassom , Ferroptose/efeitos dos fármacos , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Humanos , Apoptose/efeitos dos fármacos , Animais , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/química , Camundongos Endogâmicos BALB C , Ensaios de Seleção de Medicamentos Antitumorais , Sobrevivência Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Tamanho da Partícula , Cobalto/química , Cobalto/farmacologia , Propriedades de Superfície , Oxigênio Singlete/metabolismo , Oxigênio Singlete/química , Linhagem Celular Tumoral
10.
Acta Orthop ; 95: 174-179, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629902

RESUMO

BACKGROUND AND PURPOSE: Concerns have emerged regarding elevated levels of cobalt and chromium in patients with metal-on-metal megaprostheses. This prospective study aims to identify systemic cobalt and chromium levels in metal-on-polyethylene knee and hip megaprostheses and their associations with other factors. METHODS: 56 patients underwent knee or hip megaprosthesis surgery at 2 sarcoma centers. Serum cobalt and chromium levels were measured preoperatively and thrice within the first year using inductively coupled plasma mass spectrometry. RESULTS: A statistically significant difference in serum cobalt levels (1.4 ppb; 95% confidence interval [CI] 0.0-3.3) was observed 1 year after knee megaprosthesis surgery compared with preoperative levels. In contrast no difference in chromium levels was observed after 1 year compared with preoperative levels (0.05 ppb; CI 0.0-0.8). An association between younger age, higher eGFR, and increased cobalt levels was observed. No significant correlations were found between ion levels and resection length or the number of modular connections. CONCLUSION: We found elevated serum ion levels in metal-on-polyethylene knee megaprostheses in contrast to metal-on-polyethylene hip megaprostheses. Furthermore, a positive correlation between cobalt and chromium levels, and between cobalt and eGFR was identified, along with a negative correlation between cobalt and age. This study highlights the importance of monitoring systemic cobalt and chromium levels in patients with megaprostheses.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Cobalto , Estudos Prospectivos , Polietileno , Estudos de Coortes , Prótese de Quadril/efeitos adversos , Metais , Cromo , Artroplastia de Quadril/métodos , Desenho de Prótese
11.
Sci Rep ; 14(1): 8465, 2024 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605082

RESUMO

The relationship between oxygen sensing and autophagy in human sperms was explored in this study. Health semen and asthenozoospermia (astheno) semen were incubated with hypoxia-inducible factor-1α (HIF-1α) interferents, i.e., lificiguat (YC-1) or cobalt chloride (CoCl2), respectively. Label-free quantitative proteomic technology was used to identify the differentially expressed proteins in human semen under the hypoxia condition. Selected proteins were detected with ELISA. It was found that the autophagy levels of sperm in the YC-1 + health group or CoCl2 + astheno group increased while the vitality decreased. A total of 17, 34 and 35 differentially expressed proteins were observed in the Astheno group, the YC-1 + health group and the CoCl2 + astheno group, respectively. These proteins were primarily associated with protein processing in endoplasmic reticulum, Th17 cell differentiation, progesterone-mediated oocyte maturation, glycolysis/gluconeogenesis, HIF-1 signaling pathway, biosynthesis of amino acids, and carbon metabolism. The expression levels of protein HIF-1α, LC3B, histone H4, cathepsin L and ENO1 changed significantly in the groups. The study suggests that hypoxia can increase sperm autophagy level and reduce their vitality through HIF-1 signaling pathway and glycolysis/gluconeogenesis signaling pathway. Furthermore, proteins histone H4, cathepsin L, glutathione synthetase and ENO1 are proposed as potential biomarkers of autophagy and vitality in asthenozoospermia sperm.


Assuntos
Astenozoospermia , Histonas , Humanos , Masculino , Catepsina L , Hipóxia Celular , Proteômica , Sêmen , Hipóxia , Cobalto , Autofagia , Espermatozoides , Subunidade alfa do Fator 1 Induzível por Hipóxia
12.
Int J Mol Sci ; 25(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38673948

RESUMO

A series of bench-stable Co(II) complexes containing hydrazone Schiff base ligands were evaluated in terms of their activity and selectivity in carbon-carbon multiple bond transfer hydrogenation. These cobalt complexes, especially a Co(II) precatalyst bearing pyridine-2-yl-N(Me)N=C-(1-methyl)imidazole-2-yl ligand, activated by LiHBEt3, were successfully used in the transfer hydrogenation of substituted styrenes and phenylacetylenes with ammonia borane as a hydrogen source. Key advantages of the reported catalytic system include mild reaction conditions, high selectivity and tolerance to functional groups of substrates.


Assuntos
Boranos , Cobalto , Bases de Schiff , Hidrogenação , Cobalto/química , Bases de Schiff/química , Catálise , Boranos/química , Complexos de Coordenação/química , Alcinos/química , Amônia/química , Estrutura Molecular
13.
Chemosphere ; 357: 141965, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38621491

RESUMO

In this work, we report a supercapacitor electrode material based on nano-flower like cobalt molybdate decorated on porous activated carbon derived from waste onion peels (ß-CoMoO4-POAC). The obtained POAC exhibits highly porous structure and after the hydrothermal treatment with salts of cobalt and molybdenum, we observed a uniform distribution of ß-cobalt molybdate (ß-CoMoO4) as nano-flowers on the surface of POAC. The chemical composition, morphology and porosity of the materials were thoroughly analyzed using field emission scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, infrared spectroscopy and Brunauer-Emmet-Teller surface area measurement. Due to its flower like and highly porous morphology, ß-CoMoO4@POAC exhibits a high specific capacitance of 1110.72 F/g at a current density of 1 mA/cm2 with superior cyclic retention of 96.03% after 2000 cycles. The best electrochemical performance exhibited by ß-CoMoO4@POAC is mainly due to its high surface area and porous nature of the material which assists in active transport of ions. This study reveals the exceptional electrochemical properties of ß-CoMoO4@POAC which could be considered as a potential material for advanced energy storage devices.


Assuntos
Cobalto , Capacitância Elétrica , Eletrodos , Molibdênio , Nanocompostos , Molibdênio/química , Cobalto/química , Nanocompostos/química , Porosidade , Carvão Vegetal/química , Carbono/química
14.
Int J Biol Macromol ; 267(Pt 2): 131481, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599431

RESUMO

We developed an effective and eco-friendly strategy using chitosan gel-molten salt to achieve high loading (2.23 At. %) of single Fe-NX as assistive active sites. These sites were combined with small NiCo alloy NPs distributed on porous carbon aerogels to boost the ORR performance. The FeSAs-NiCo alloy@N-C sphere exhibits exceptional mass activity and specific activity of 3.705 A.mg-1 and 8.79 mA.cm-2(ECSA), respectively, at 0.85 V versus RHE. It has a superior onset potential of 1.08 V versus RHE, surpassing that of its nanoparticle Fe counterpart and NiCo alloy@N-C sphere. The significant improvement in ORR performance of the FeSAs-NiCo alloy@N-C sphere could be attributed to the positive effects of increased lattice strain due to the single atoms of Fe-NX hybridized with small NiCo alloy NPs. The chitosan gel-assisted molten salt strategy and assistive active sites of Fe-NX hybridized with NiCo alloy NPs regulate the electronic properties of the FeSAs-NiCo alloy@N-C sphere, both geometrically via lattice strain mismatch and electronically through shifting of the d-band center. This could influence the binding energies for oxygen and/or oxygen reduction intermediate adsorption/desorption. The additional improvement in the ORR performance of the FeSAs-NiCo alloy@N-C sphere also benefits from having a lower electrochemical activation energy.


Assuntos
Ligas , Quitosana , Géis , Oxirredução , Oxigênio , Quitosana/química , Oxigênio/química , Ligas/química , Géis/química , Ferro/química , Nanopartículas Metálicas/química , Níquel/química , Cobalto/química , Catálise , Sais/química
15.
J Mater Chem B ; 12(19): 4642-4654, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38592460

RESUMO

The therapeutic efficacy of Fenton or Fenton-like nanocatalysts is usually restricted by the inappropriate pH value and limited concentration of hydrogen peroxide (H2O2) at the tumor site. Herein, calcium carbonate (CaCO3)-mineralized cobalt silicate hydroxide hollow nanocatalysts (CSO@CaCO3, CC) were synthesized and loaded with curcumin (CCC). This hybrid system can simultaneously realize nanocatalytic therapy, chemotherapy and calcium overload. With the stabilization of liposomes, CCC is able to reach the tumor site smoothly. The CaCO3 shell first degrades in an acidic tumor environment, releasing Cur and Ca2+, and the pH value of the tumor is increased simultaneously. Then the exposed CSO catalyzes the Fenton-like reaction to convert H2O2 into ˙OH and enhances the cytotoxicity of curcumin (Cur) by catalytically oxidizing it to a ˙Cur radical. Curcumin not only induces the chemotherapy effect but also serves as a nucleophilic ligand and an electron donor in the catalytic system, enhancing the Fenton-like activity of CCC by electron transfer. In addition, calcium overload also amplifies the efficacy of ROS-based therapy. In vitro and in vivo results show that CCC exhibited an excellent synergistic tumor inhibition effect without any clear side effect. This work proposes a novel concept of nanocatalytic therapy/chemotherapy synergistic mechanism by the ligand-induced enhancement of Fenton-like catalytic activity, and inspires the construction of combined therapeutic nanoplatforms and multifunctional nanocarriers for drug and ion delivery in the future.


Assuntos
Antineoplásicos , Cálcio , Cobalto , Curcumina , Nanopartículas , Curcumina/química , Curcumina/farmacologia , Cobalto/química , Cobalto/farmacologia , Humanos , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Camundongos , Cálcio/química , Cálcio/metabolismo , Nanopartículas/química , Catálise , Carbonato de Cálcio/química , Ligantes , Tamanho da Partícula , Camundongos Endogâmicos BALB C , Portadores de Fármacos/química , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células/efeitos dos fármacos , Feminino , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular Tumoral
16.
Int J Mol Sci ; 25(7)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38612848

RESUMO

The rational design of advanced electrocatalysts at the molecular or atomic level is important for improving the performance of hydrogen evolution reactions (HERs) and replacing precious metal catalysts. In this study, we describe the fabrication of electrocatalysts based on Fe, Co, or Ni single atoms supported on titanium carbide (TiC) using the molten salt method, i.e., TiC-FeSA, TiC-CoSA, or TiC-NiSA, to enhance HER performance. The introduction of uniformly distributed transition-metal single atoms successfully reduces the overpotential of HERs. Overpotentials of TiC-FeSA at 10 mA cm-2 are 123.4 mV with 61.1 mV dec-1 Tafel slope under acidic conditions and 184.2 mV with 85.1 mV dec-1 Tafel slope under alkaline conditions, which are superior to TiC-NiSA and TiC-CoSA. TiC samples loaded with transition-metal single atoms exhibit high catalytic activity and long stability under acidic and basic conditions. Density functional theory calculations indicate that the introduction of transition-metal single atoms effectively reduces the HER barrier of TiC-based electrocatalysts.


Assuntos
Ferro , Níquel , Titânio , Cobalto , Hidrogênio
17.
J Colloid Interface Sci ; 666: 512-528, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38613974

RESUMO

Metronidazole (MNZ), a commonly used antibiotic, poses risks to water bodies and human health due to its potential carcinogenic, mutagenic, and genotoxic effects. In this study, mesoporous cobalt-manganese layered double hydroxides (CoxMny-LDH) with abundant oxygen vacancies (Ov) were successfully synthesized using the co-precipitation method and used to activate calcium sulfite (CaSO3) with slight soluble in water for MNZ degradation. The characterization results revealed that Co2Mn-LDH had higher specific areas and exhibited good crystallinity. Co2Mn-LDH/CaSO3 exhibited the best catalytic performance under optimal conditions, achieving a remarkable MNZ degradation efficiency of up to 98.1 % in only 8 min. Quenching experiments and electron paramagnetic resonance (EPR) tests showed that SO4•- and 1O2 played pivotal roles in the MNZ degradation process by activated CaSO3, while the redox cycles of Co2+/Co3+ and Mn3+/Mn4+ on the catalyst surface accelerated electron transfer, promoting radical generation. Three MNZ degradation routes were put forward based on the density functional theory (DFT) and liquid chromatography-mass spectrometer (LC-MS) analysis. Meanwhile, the toxicity analysis result demonstrated that the toxicity of intermediates post-catalytic reaction was decreased. Furthermore, the Co2Mn-LDH/CaSO3 system displayed excellent stability, reusability, and anti-interference capability, and achieved a comparably high removal efficiency across various organic pollutant water bodies. This study provides valuable insights into the development and optimization of effective heterogeneous catalysts for treating antibiotic-contaminated wastewater.


Assuntos
Cobalto , Hidróxidos , Manganês , Metronidazol , Cobalto/química , Metronidazol/química , Hidróxidos/química , Manganês/química , Porosidade , Propriedades de Superfície , Sulfitos/química , Catálise , Tamanho da Partícula , Teoria da Densidade Funcional , Poluentes Químicos da Água/química
18.
Anal Methods ; 16(16): 2496-2504, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38578053

RESUMO

This work describes an electrochemical sensor for the fast noninvasive detection of uric acid (UA) in saliva. The sensing material was based on a cobalt-containing Prussian blue analogue (Na2-xCo[Fe(CN)6]1-y, PCF). By optimizing the ratio of Co and Fe as 1.5 : 1 in PCF (PCF1.5,0), particles with a regular nanocubic morphology were formed. The calcination of PCF1.5,0 produced a carbon-coated CoFe alloy (CCF1.5), which possessed abundant defects and achieved an excellent electrochemical performance. Subsequently, CCF1.5 was modified on a screen-printed carbon electrode (SPCE) to fabricate the electrochemical sensor, CCF1.5/SPCE, which showed a sensitive and selective response toward salivary UA owing to its good conductivity, sufficient surface active sites and efficient catalytic activity. The determination of UA in artificial saliva achieved the wide linear range of 40 nM-30 µM and the low limit of detection (LOD) of 15.3 nM (3σ/s of 3). The performances of the sensor including its reproducibility, stability and selectivity were estimated to be satisfactory. The content of UA in human saliva was determined and the recovery was in the range of 98-107% and the total RSD was 4.14%. The results confirmed the reliability of CCF1.5/SPCE for application in noninvasive detection.


Assuntos
Ligas , Carbono , Cobalto , Técnicas Eletroquímicas , Ferrocianetos , Ácido Úrico , Ácido Úrico/química , Ácido Úrico/análise , Ferrocianetos/química , Cobalto/química , Carbono/química , Humanos , Técnicas Eletroquímicas/métodos , Ligas/química , Ferro/química , Limite de Detecção , Nanopartículas Metálicas/química , Saliva/química , Reprodutibilidade dos Testes , Eletrodos
19.
Occup Environ Med ; 81(4): 220-224, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38641364

RESUMO

BACKGROUND: Occupational exposure to metals can be associated with respiratory diseases which can adversely affect the individual's health, finances and employment. Despite this, little is known about the incidence of these respiratory conditions over prolonged periods of time. AIMS: This study aimed to investigate the trends in the incidence of work-related respiratory diseases attributed to nickel, chromium and cobalt in the UK. METHODS: Cases of occupational respiratory diseases caused by nickel, chromium or cobalt reported to Surveillance of Work-related and Occupational Respiratory Disease (SWORD), the UK-based surveillance scheme between 1996 and 2019 (inclusive), were extracted and grouped into six 4-year time periods. Cases were characterised by causative metal exposure, occupational and industrial sector. Incidence rates diseases (adjusted for physician participation and response rate) were calculated using ONS employment data. RESULTS: Of cases reported to SWORD during the study period, 1% (173 actual cases) of respiratory problems were attributed to nickel, chromium or cobalt. Diagnoses of asthma compromised the largest proportion of diagnoses (74.4%), followed by lung cancer (8.9%) and pneumoconiosis (6.7%). Cases had a mean age of 47 years (SD 13); 93% were men. The annual incidence fell from 1.6 per million employed in the first 4-year period, to 0.2 in the most recent period. CONCLUSIONS: Over 24 years, a decline in the incidence of metal-related occupational respiratory diseases was observed in the UK. This could be attributed to improvements in working conditions which resulted in reduced metal exposure but could also be due to closure of industries that might have generated case returns.


Assuntos
Cromo , Cobalto , Níquel , Doenças Profissionais , Exposição Ocupacional , Humanos , Reino Unido/epidemiologia , Masculino , Pessoa de Meia-Idade , Níquel/efeitos adversos , Cromo/efeitos adversos , Feminino , Cobalto/efeitos adversos , Doenças Profissionais/epidemiologia , Doenças Profissionais/induzido quimicamente , Adulto , Exposição Ocupacional/efeitos adversos , Incidência , Pneumoconiose/epidemiologia , Pneumoconiose/etiologia , Doenças Respiratórias/epidemiologia , Doenças Respiratórias/etiologia , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/etiologia
20.
Waste Manag ; 181: 199-210, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38643515

RESUMO

Supercritical CO2 (scCO2) extraction assisted by complexing copolymers is a promising process to recover valuable metals from lithium-ion batteries (LIBs). CO2, in addition to being non-toxic, abundant and non-flammable, allows an easy separation of metal-complexes from the extraction medium by depressurization, limiting the wastewater production. In this study, CO2-philic gradient copolymers bearing phosphonic diacid complexing groups (poly(vinylbenzylphosphonic diacid-co-1,1,2,2-tetrahydroperfluorodecylacrylate), p(VBPDA-co-FDA)) were synthesized for the extraction of lithium and cobalt from LiCoO2 cathode material. Notably, the copolymer was able to play the triple role of leaching agent, complexing agent and surfactant. The proof of concept for leaching, complexation and extraction was achieved, using two different extraction systems. A first extraction system used aqueous hydrogen peroxide as reducing agent while it was replaced by ethanol in the second extraction system. The scCO2 extraction conditions such as extraction time, temperature, functional copolymer concentration, and the presence of additives were optimized to improve the metals extraction from LiCoO2 cathode material, leading to an extraction efficiency of Li and Co up to ca. 75 % at 60 °C and 250 bar.


Assuntos
Dióxido de Carbono , Cobalto , Lítio , Polímeros , Cobalto/química , Cobalto/isolamento & purificação , Lítio/química , Dióxido de Carbono/química , Polímeros/química , Óxidos/química , Reciclagem/métodos , Eletrodos , Fontes de Energia Elétrica
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