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1.
Environ Geochem Health ; 46(8): 266, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954124

RESUMO

Recently, the hazardous effects of antibiotic micropollutants on the environment and human health have become a major concern. To address this challenge, semiconductor-based photocatalysis has emerged as a promising solution for environmental remediation. Our study has developed Bi2WO6/g-C3N4 (BWCN) photocatalyst with unique characteristics such as reactive surface sites, enhanced charge transfer efficiency, and accelerated separation of photogenerated electron-hole pairs. BWCN was utilized for the oxidation of tetracycline antibiotic (TCA) in different water sources. It displayed remarkable TCA removal efficiencies in the following order: surface water (99.8%) > sewage water (88.2%) > hospital water (80.7%). Further, reusability tests demonstrated sustained performance of BWCN after three cycles with removal efficiencies of 87.3, 71.2 and 65.9% in surface water, sewage, and hospital water, respectively. A proposed photocatalytic mechanism was delineated, focusing on the interaction between reactive radicals and TCA molecules. Besides, the transformation products generated during the photodegradation of TCA were determined, along with the discussion on the potential risk assessment of antibiotic pollutants. This study introduces an approach for utilizing BWCN photocatalyst, with promising applications in the treatment of TCA from various wastewater sources.


Assuntos
Antibacterianos , Oxirredução , Tetraciclina , Poluentes Químicos da Água , Poluentes Químicos da Água/química , Antibacterianos/química , Tetraciclina/química , Catálise , Águas Residuárias/química , Bismuto/química , Grafite/química , Compostos de Nitrogênio/química , Compostos de Tungstênio/química , Fotólise , Purificação da Água/métodos , Esgotos/química
2.
Nat Commun ; 15(1): 5508, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951161

RESUMO

Keratoconus, a disorder characterized by corneal thinning and weakening, results in vision loss. Corneal crosslinking (CXL) can halt the progression of keratoconus. The development of accelerated corneal crosslinking (A-CXL) protocols to shorten the treatment time has been hampered by the rapid depletion of stromal oxygen when higher UVA intensities are used, resulting in a reduced cross-linking effect. It is therefore imperative to develop better methods to increase the oxygen concentration within the corneal stroma during the A-CXL process. Photocatalytic oxygen-generating nanomaterials are promising candidates to solve the hypoxia problem during A-CXL. Biocompatible graphitic carbon nitride (g-C3N4) quantum dots (QDs)-based oxygen self-sufficient platforms including g-C3N4 QDs and riboflavin/g-C3N4 QDs composites (RF@g-C3N4 QDs) have been developed in this study. Both display excellent photocatalytic oxygen generation ability, high reactive oxygen species (ROS) yield, and excellent biosafety. More importantly, the A-CXL effect of the g-C3N4 QDs or RF@g-C3N4 QDs composite on male New Zealand white rabbits is better than that of the riboflavin 5'-phosphate sodium (RF) A-CXL protocol under the same conditions, indicating excellent strengthening of the cornea after A-CXL treatments. These lead us to suggest the potential application of g-C3N4 QDs in A-CXL for corneal ectasias and other corneal diseases.


Assuntos
Reagentes de Ligações Cruzadas , Grafite , Oxigênio , Pontos Quânticos , Riboflavina , Pontos Quânticos/química , Animais , Grafite/química , Oxigênio/metabolismo , Riboflavina/farmacologia , Coelhos , Masculino , Reagentes de Ligações Cruzadas/química , Compostos de Nitrogênio/química , Espécies Reativas de Oxigênio/metabolismo , Ceratocone/tratamento farmacológico , Ceratocone/metabolismo , Raios Ultravioleta , Córnea/efeitos dos fármacos , Córnea/metabolismo , Córnea/patologia , Humanos , Fármacos Fotossensibilizantes/farmacologia , Substância Própria/metabolismo , Substância Própria/efeitos dos fármacos
3.
Environ Geochem Health ; 46(8): 302, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990227

RESUMO

In this study, a highly efficient CoFe2O4-anchored g-C3N4 nanocomposite with Z-scheme photocatalyst was developed by facile calcination and hydrothermal technique. To evaluate the crystalline structure, sample surface morphology, elemental compositions, and charge conductivity of the as-synthesized catalysts by various characterization techniques. The high interfacial contact of CoFe2O4 nanoparticles (NPs) with g-C3N4 nanosheets reduced the optical bandgap from 2.67 to 2.5 eV, which improved the charge carrier separation and transfer. The photo-degradation of methylene blue (MB) and rhodamine B (Rh B) aqueous pollutant suspension under visible-light influence was used to investigate the photocatalytic degradation activity of the efficient CoFe2O4/g-C3N4 composite catalyst. The heterostructured spinel CoFe2O4 anchored g-C3N4 photocatalysts (PCs) with Z-scheme show better photocatalytic degradation performance for both organic dyes. Meanwhile, the efficiency of aqueous MB and Rh B degradation in 120 and 100 min under visible-light could be up to 91.1% and 73.7%, which is greater than pristine g-C3N4 and CoFe2O4 catalysts. The recycling stability test showed no significant changes in the photo-degradation activity after four repeated cycles. Thus, this work provides an efficient tactic for the construction of highly efficient magnetic PCs for the removal of hazardous pollutants in the aquatic environment.


Assuntos
Cobalto , Compostos Férricos , Azul de Metileno , Nanocompostos , Rodaminas , Poluentes Químicos da Água , Cobalto/química , Compostos Férricos/química , Catálise , Nanocompostos/química , Rodaminas/química , Poluentes Químicos da Água/química , Azul de Metileno/química , Fotólise , Luz , Compostos Inorgânicos de Carbono/química , Nitrilas/química , Processos Fotoquímicos , Compostos de Nitrogênio/química , Grafite
4.
Anal Chim Acta ; 1316: 342867, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-38969430

RESUMO

BACKGROUND: Kanamycin (KAN) residues in animal-derived foods continuously enter the human body, which will pose serious threats to human health such as hearing loss, nephrotoxicity and other complications. Therefore, to sensitively detect KAN residues by a reliable technology is extremely urgent in food quality and safety. Compared with traditional methods being limited by cost and complexity, photoelectrochemical (PEC) biosensors benefit from some merits such as rapid response, excellent sensitivity and good stability. In this study, the construction of a highly efficient PEC platform to realize KAN residues detection is discussed. RESULTS: Herein, a novel p-n heterojunction consisting of flower-like BiOI microspheres and graphite carbon nitride (g-C3N4) nanoflakes was developed to establish a PEC aptasensor for KAN detection at 0 V. The prepared g-C3N4/BiOI heterostructure showed not only significantly enhanced PEC activity due to the larger specific surface area but also greatly increased charge separation efficiency owing to the strong internal electric field. Meanwhile, using g-C3N4/BiOI as a highly efficient photoactive material for binding amine-functionalized aptamers to capture KAN, the photocurrent signals showed a 'turn off' mode to achieve the sensitive detection of KAN. The proposed PEC aptasensor exhibited linear response for KAN from 5 × 10-9 to 3 × 10-7 mol L-1 with a low detection limit of 1.31 × 10-9 mol L-1, and satisfactory recoveries (97.44-107.38 %) were obtained in real food samples analysis. SIGNIFICANCE: This work presented a novel p-n heterojunction-based PEC aptasensor with strong selectivity and stability, rendering it allowed to detect KAN in animal-derived foods including milk, honey and pork. Additionally, the detection range satisfied the MRLs for KAN specified by the national standards, demonstrating the potential application for food analysis. The study provides a new insight into the development of efficient and practical biosensors for antibiotic residues detection.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Técnicas Eletroquímicas , Grafite , Canamicina , Aptâmeros de Nucleotídeos/química , Técnicas Eletroquímicas/métodos , Grafite/química , Técnicas Biossensoriais/métodos , Canamicina/análise , Processos Fotoquímicos , Limite de Detecção , Contaminação de Alimentos/análise , Compostos de Nitrogênio/química , Animais , Nitrilas/química , Antibacterianos/análise , Bismuto
5.
Mikrochim Acta ; 191(7): 411, 2024 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900245

RESUMO

Ratiometric fluorescence and colorimetric strategies for detecting activity of butyrylcholinesterase (BChE) in human serum were developed by using g-C3N4 nanosheets, silver ion (Ag+) and o-phenylenediamine (OPD) as chromogenic agents. The oxidation-reduction reaction of OPD and Ag+ generates 2,3-diaminophenazine (oxOPD). Under exciation at 370 nm, g-C3N4 nanosheets and oxOPD emit fluorescence at 440 nm (F440) and 560 nm (F560), respectively. Additionally, oxOPD exhibits quenching ability towards g-C3N4 nanosheets via photoinduced electron transfer (PET) process. Thiocholine (TCh), as a product of BChE-catalyzed hydrolysis reaction of butylthiocholine iodide (BTCh), can coordinate with Ag+ intensively, and consequently diminish the amount of free Ag+ in the testing system. Less amount of free Ag+ leads to less production of oxOPD, resulting in less fluorescence quenching towards g-C3N4 nanosheets as well as less fluorescence emission of oxOPD. Therefore, by using g-C3N4 nanosheets and oxOPD as fluorescence indicators, the intensity ratio of their fluorescence (F440/F560) was calculated and employed to evaluate the activity of BChE. Similarly, the color variation of oxOPD indicated by the absorbance at 420 nm (ΔA420) was monitored for the same purpose. These strategies were validated to be sensitive and selective for detecting BChE activity in human serum, with limits of detection (LODs) of 0.1 U L-1 for ratiometric fluorescence mode and 0.7 U L-1 for colorimetric mode.


Assuntos
Butirilcolinesterase , Colorimetria , Nanoestruturas , Fenilenodiaminas , Prata , Espectrometria de Fluorescência , Humanos , Colorimetria/métodos , Prata/química , Fenilenodiaminas/química , Butirilcolinesterase/sangue , Butirilcolinesterase/química , Espectrometria de Fluorescência/métodos , Nanoestruturas/química , Compostos de Nitrogênio/química , Limite de Detecção , Nitrilas/química , Grafite , Fenazinas
6.
Environ Res ; 257: 119293, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38838749

RESUMO

Recently, photocatalysis combined peroxydisulfate activation under visible light (PC-PDS/Vis) was developed as a promising technology for removing antibiotics in water. Herein, Mn doped FeOOH (Mn-FeOOH) nanoclusters were grown in-situ on the surface of graphitic carbon nitride nanosheets (CNNS) using a wet chemical method, which served as a visible-light-driven photocatalyst for peroxydisulfate (PDS) activation. Photovoltaic property characterizations revealed that Mn-FeOOH/CNNS owned superior light capture ability and carrier separation efficiency. According to DFT calculations, the synergistic effect between Mn and Fe species was proved to enhance the adsorption and activation of PDS. 99.7% of tetracycline (TC) was rapidly removed in 50 min in the PC-PDS/Vis system. In addition, Mn-FeOOH/CNNS exhibited high recycling stability with low iron leaching, attributed to the interaction between Mn-FeOOH clusters and carbon species. Quenching experiments and electron spin resonance (ESR) tests unveiled that •O2- played a significant role in TC removal, while •OH and SO4•- acted as additional roles contributing to the overall process. These findings given a new strategy for antibiotics degradation by photocatalysis, offering deeper insights for the advancement of sustainable and cutting-edge wastewater treatment technologies.


Assuntos
Grafite , Luz , Tetraciclina , Poluentes Químicos da Água , Tetraciclina/química , Poluentes Químicos da Água/química , Grafite/química , Catálise , Antibacterianos/química , Manganês/química , Sulfatos/química , Compostos de Nitrogênio/química , Ferro/química , Processos Fotoquímicos
7.
Environ Geochem Health ; 46(7): 219, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849667

RESUMO

This study investigates the removal of amoxicillin micropollutants (AM) from hospital wastewater using CoMoO4-modified graphitic carbon nitride (CMO/gCN). Consequently, CMO/gCN exhibits notable improvements in visible light absorption and electron-hole separation rates compared to unmodified gCN. Besides, CMO/gCN significantly enhances the removal efficiency of AM, attaining an impressive 96.5%, far surpassing the performance of gCN at 48.6%. Moreover, CMO/gCN showcases outstanding reusability, with AM degradation performance exceeding 70% even after undergoing six cycles of reuse. The removal mechanism of AM employing CMO/gCN involves various photoreactions of radicals (•OH, •O2-) and amoxicillin molecules under light assistance. Furthermore, CMO/gCN demonstrates a noteworthy photodegradation efficiency of AM from hospital wastewater, reaching 92.8%, with a near-complete reduction in total organic carbon levels. Detailed discussions on the practical applications of the CMO/gCN photocatalyst for removal of micropollutants from hospital wastewater are provided. These findings underline the considerable potential of CMO/gCN for effectively removing various pollutants in environmental remediation strategies.


Assuntos
Amoxicilina , Grafite , Oxirredução , Águas Residuárias , Poluentes Químicos da Água , Amoxicilina/química , Águas Residuárias/química , Grafite/química , Poluentes Químicos da Água/química , Fotólise , Hospitais , Compostos de Nitrogênio/química , Catálise , Purificação da Água/métodos
8.
Colloids Surf B Biointerfaces ; 240: 113998, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38823340

RESUMO

Photoactivated therapy has gradually emerged as a promising and rapid method for combating bacteria, aimed at overcoming the emergence of drug-resistant strains resulting from the inappropriate use of antibiotics and the subsequent health risks. In this work, we report the facile fabrication of Zn3[Fe(CN)6]/g-C3N4 nanocomposites (denoted as ZHF/g-C3N4) through the in-situ loading of zinc hexacyanoferrate nanospheres onto two-dimensional g-C3N4 sheets using a simple metal-organic frameworks construction method. The ZHF/g-C3N4 nanocomposite exhibits enhanced antibacterial activity through the synergistic combination of the excellent photothermal properties of ZHF and the photodynamic capabilities of g-C3N4. Under dual-light irradiation (420 nm + 808 nm NIR), the nanocomposites achieve remarkable bactericidal efficacy, eliminating 99.98% of Escherichia coli and 99.87% of Staphylococcus aureus within 10 minutes. Furthermore, in vivo animal experiments have demonstrated the outstanding capacity of the composite in promoting infected wound healing, achieving a remarkable wound closure rate of 99.22% after a 10-day treatment period. This study emphasizes the potential of the ZHF/g-C3N4 nanocomposite in effective antimicrobial applications, expanding the scope of synergistic photothermal/photodynamic therapy strategies.


Assuntos
Antibacterianos , Escherichia coli , Nanocompostos , Staphylococcus aureus , Cicatrização , Nanocompostos/química , Cicatrização/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Animais , Fotoquimioterapia , Testes de Sensibilidade Microbiana , Camundongos , Esterilização/métodos , Ferrocianetos/química , Ferrocianetos/farmacologia , Tamanho da Partícula , Zinco/química , Zinco/farmacologia , Terapia Fototérmica , Propriedades de Superfície , Compostos de Nitrogênio/química , Compostos de Nitrogênio/farmacologia , Grafite
9.
Bioresour Technol ; 404: 130915, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823561

RESUMO

This work proposes the pyrolysis of the cassava plant shoot system biomass and a comprehensive chemical characterization of the resulting bio-oil. The highest yields of liquid products were obtained at 600 °C, with 12.6 % bio-oil (organic fraction), which presented the lowest total acid number of 65.7 mg KOH g-1. The bio-oil produced at 500 °C exhibited the highest total phenolic content of approximately 41 % GAE, confirmed by GC/MS analysis (33.8 % of the total area). FT-Orbitrap MS analysis found hundreds of oxygenated constituents in the bio-oils, belonging to the O2-7 classes, as well as nitrogen compounds from the Ny and OxNy classes. Higher pyrolysis temperatures resulted in more oxygenated phenolics (O4-7) undergoing secondary degradation and deoxygenation reactions, generating O2-3 compounds. Additional classes affected were O3-5N2-3, while O1-2N1 presented more stable compounds. These findings show that cassava bio-oils are promising sources of renewable chemicals.


Assuntos
Manihot , Oxigênio , Brotos de Planta , Pirólise , Manihot/química , Brotos de Planta/química , Oxigênio/metabolismo , Nitrogênio , Biocombustíveis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas/métodos , Compostos de Nitrogênio/química , Óleos de Plantas , Polifenóis
10.
Chemosphere ; 361: 142522, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38838869

RESUMO

Selecting safe, non-toxic, and non-metallic semiconductor materials that facilitate the degradation of pollutants in water stands out as an optimal approach to combat environmental pollution. Herein, graphitic carbon nitride (g-C3N4)-based hollow nanospheres nonmetallic photocatalyst modified with covalent organic framework materials named TpMA, based on 1, 3, 5-trimethylchloroglucuronide (Tp) and melamine (MA), was successfully synthesized (abbreviated as CNTP). The ordered electron donor-acceptor structure inherent in TpMA contributed to enhancing the transport efficiency of photogenerated carriers in CNTP. The CNTP photocatalysts exhibited excellent performance in degrading rhodamine B and tetracycline in visible light, with optimal degradation rates reached more than 90% in 60 and 80 min, respectively, which were 5.3 and 3.0 times higher than those of pure CNNS. The increased photocatalytic efficiency observed in CNTP composites could be traced back to the covalently connection between the two molecules, forming a π-conjugated system that facilitated the separative efficiency of photogenerated electron-hole pairs and intensified the utilization of visible light. This study provided a new means to design and fabricate highly efficient and environmentally friendly non-metallic photocatalytic materials.


Assuntos
Grafite , Nanosferas , Compostos de Nitrogênio , Rodaminas , Triazinas , Poluentes Químicos da Água , Nanosferas/química , Catálise , Triazinas/química , Grafite/química , Rodaminas/química , Compostos de Nitrogênio/química , Poluentes Químicos da Água/química , Luz , Tetraciclina/química , Nitrilas/química , Processos Fotoquímicos , Fotólise
11.
Chemosphere ; 361: 142517, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38830464

RESUMO

Indoor volatile formaldehyde is a serious health hazard. The development of low-temperature and efficient nonhomogeneous oxidation catalysts is crucial for protecting human health and the environment but is also quite challenging. Single-atom catalysts (SACs) with active centers and coordination environments that are precisely tunable at the atomic level exhibit excellent catalytic activity in many catalytic fields. Among two-dimensional materials, the nonmagnetic monolayer material g-C3N4 may be a good platform for loading single atoms. In this study, the effect of nitrogen defect formation on the charge distribution of g-C3N4 is discussed in detail using density functional theory (DFT) calculations. The effect of nitrogen defects on the activated molecular oxygen of Pt/C3N4 was systematically revealed by DFT calculations in combination with molecular orbital theory. Two typical reaction mechanisms for the catalytic oxidation of formaldehyde were proposed based on the Eley-Rideal (E-R) mechanism. Pt/C3N4-V3N was more advantageous for path 1, as determined by the activation energy barrier of the rate-determining step and product desorption. Finally, the active centers and chemical structures of Pt/C3N4 and Pt/C3N4-V3N were verified to have good stability at 375 K by determination of the migration energy barriers and ab initio molecular dynamics simulations. Therefore, the formation of N defects can effectively anchor single-atom Pt and provide additional active sites, which in turn activate molecular oxygen to efficiently catalyze the oxidation of formaldehyde. This study provides a better understanding of the mechanism of formaldehyde oxidation by single-atom Pt catalysts and a new idea for the development of Pt as well as other metal-based single-atom oxidation catalysts.


Assuntos
Teoria da Densidade Funcional , Formaldeído , Oxirredução , Platina , Formaldeído/química , Catálise , Platina/química , Compostos de Nitrogênio/química , Simulação de Dinâmica Molecular , Oxigênio/química , Grafite
12.
Water Sci Technol ; 89(11): 3047-3078, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38877630

RESUMO

Graphitic carbon nitride (g-C3N4) is a widely studied visible-light-active photocatalyst for low cost, non-toxicity, and facile synthesis. Nonetheless, its photocatalytic efficiency is below par, due to fast recombination of charge carriers, low surface area, and insufficient visible light absorption. Thus, the research on the modification of g-C3N4 targeting at enhanced photocatalytic performance has attracted extensive interest. A considerable amount of review articles have been published on the modification of g-C3N4 for applications. However, limited effort has been specially contributed to providing an overview and comparison on available modification strategies for improved photocatalytic activity of g-C3N4-based catalysts in antibiotics removal. There has been no attempt on the comparison of photocatalytic performances in antibiotics removal between modified g-C3N4 and other known catalysts. To address these, our study reviewed strategies that have been reported to modify g-C3N4, including metal/non-metal doping, defect tuning, structural engineering, heterostructure formation, etc. as well as compared their performances for antibiotics removal. The heterostructure formation was the most widely studied and promising route to modify g-C3N4 with superior activity. As compared to other known photocatalysts, the heterojunction g-C3N4 showed competitive performances in degradation of selected antibiotics. Related mechanisms were discussed, and finally, we revealed current challenges in practical application.


Assuntos
Antibacterianos , Grafite , Luz , Compostos de Nitrogênio , Poluentes Químicos da Água , Antibacterianos/química , Grafite/química , Catálise , Compostos de Nitrogênio/química , Poluentes Químicos da Água/química , Fotólise , Processos Fotoquímicos , Nitrilas
13.
Talanta ; 277: 126321, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38805945

RESUMO

In this article, ferric ion-doped floral graphite carbon nitride (Fe-CN-3, energy donor) was used to construct the substrate of the immunosensor and copper oxide nanocubes (Cu2O, energy acceptor) were taken as an efficient ECL quenching probe. A sandwich quench electrochemiluminescence (ECL) immunosensor for soluble cytokeratin 19 fragment (Cyfra21-1) detection was preliminarily developed based on a novel resonant energy transfer donor-acceptor pair. Fe-CN-3, a carbon nitride that combines the advantages of metal ion doping as well as morphology modulation, is used in ECL luminophores to provide more excellent ECL performance, which makes a significant contribution to the application and development of carbon nitride in the field of ECL biosensors. The regular shape, high specific surface area and excellent biocompatibility of the quencher Cu2O nanocubes facilitate the labeling of secondary antibodies and the construction of sensors. Meanwhile, as an energy acceptor, the UV absorption spectrum of Cu2O can overlap efficiently with the energy donor's ECL emission spectrum, making it prone to the occurrence of ECL-RET and thus obtaining an excellent quenching effect. These merits of the donor-acceptor pair enable the sensor to have a wide detection range of 0.00005-100 ng/mL and a low detection limit of 17.4 fg/mL (S/N = 3), which provides a new approach and theoretical basis for the clinical detection of lung cancer.


Assuntos
Antígenos de Neoplasias , Técnicas Biossensoriais , Cobre , Técnicas Eletroquímicas , Grafite , Queratina-19 , Medições Luminescentes , Cobre/química , Queratina-19/análise , Queratina-19/imunologia , Técnicas Eletroquímicas/métodos , Humanos , Grafite/química , Técnicas Biossensoriais/métodos , Medições Luminescentes/métodos , Imunoensaio/métodos , Antígenos de Neoplasias/análise , Antígenos de Neoplasias/imunologia , Limite de Detecção , Compostos de Nitrogênio/química , Nitrilas/química
14.
ACS Appl Mater Interfaces ; 16(20): 25727-25739, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38742469

RESUMO

The development of engineered nanomaterials has been considered a promising strategy to control oral infections. In this study, silver-embedded carbon nitrides (Ag@g-CN) were synthesized and tested against Candida albicans, investigating their antifungal action and biocompatibility in animal cells. Ag@g-CN was synthesized by a simple one-pot thermal polymerization technique and characterized by various analytical techniques. X-ray diffraction (XRD) analysis revealed slight alterations in the crystal structure of g-CN upon the incorporation of Ag. Fourier transform infrared (FT-IR) spectroscopy confirmed the presence of Ag-N bonds, indicating successful silver incorporation and potential interactions with g-CN's amino groups. UV-vis spectroscopy demonstrated a red shift in the absorption edge of Ag@g-CN compared with g-CN, attributed to the surface plasmon resonance effect of silver nanoparticles. Field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) confirmed the 2D layered sheet like morphology of both materials. The Ag 3d peaks found in X-ray photoelectron spectroscopy (XPS) confirmed the presence of metallic Ag0 nanoparticles in Ag@g-CN. The Ag@g-CN materials exhibited high antifungal activity against reference and oral clinical strains of C. albicans, with minimal inhibitory concentration (MIC) ranges between 16-256 µg/mL. The mechanism of Ag@g-CN on C. albicans was attributed to the disruption of the membrane integrity and disturbance of the biofilm. In addition, the Ag@g-CN material showed good biocompatibility in the fibroblastic cell line and in Galleria mellonella, with no apparent cytotoxicity observed at a concentration up to 1000 µg/mL. These findings demonstrate the potential of the Ag@g-CN material as an effective and safe antifungal agent for the treatment of oral fungal infections.


Assuntos
Antifúngicos , Candida albicans , Nanopartículas Metálicas , Prata , Candida albicans/efeitos dos fármacos , Prata/química , Prata/farmacologia , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/síntese química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Animais , Testes de Sensibilidade Microbiana , Compostos de Nitrogênio/química , Compostos de Nitrogênio/farmacologia , Compostos de Nitrogênio/toxicidade , Camundongos , Nitrilas
15.
Anal Chim Acta ; 1311: 342715, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38816154

RESUMO

BACKGROUND: Due to that the higher activity of nanozymes would bring outstanding performance for the nanozyme-based biosensing strategies, great efforts have been made by researchers to improve the catalytic activity of nanozymes, and novel nanozymes with high catalytic activity are desired. Considering the crucial role in controlling blood glucose level, strategies like colorimetric and chemiluminescence to monitor α-glucosidase are developed. However, multi-mode detection with higher sensitivity was insufficient. Therefore, developing triple-mode detection method for α-glucosidase based on great performance nanozyme is of great importance. RESULTS: In this work, a novel nanozyme Cu-BCN was synthesized by loading Cu on boron doped carbon substrate g-C3N4 and applied to the colorimetric-fluorescent-smartphone triple-mode detection of α-glucosidase. In the presence of H2O2, Cu-BCN catalyzed the generation of 1O2 from H2O2, 1O2 subsequently oxidized TMB to blue colored oxTMB. In the presence of hydroquinone (HQ), the ROS produced from H2O2 was consumed, inhibiting the oxidation of TMB, which endows the possibility of colorimetric and visual on-site detection of HQ. Further, due to that the fluorescence of Mg-CQDs at 444 nm could be quenched by oxTMB, HQ could also be quantified through fluorescent mode. Since α-glucosidase could efficiently hydrolyze α-arbutin into HQ, the sensitive detection of α-glucosidase was realized. Further, colorimetric paper-based device (c-PAD) was fabricated for on-site α-glucosidase detection. The LODs for α-glucosidase via three modes were 2.20, 1.62 and 2.83 U/L respectively, high sensitivities were realized. SIGNIFICANCE: The nanozyme Cu-BCN possesses higher peroxidase-like activity by doping boron to the substrate than non-doped Cu-CN. The proposed triple-mode detection of α-glucosidase is more sensitive than most previous reports, and is reliable when applied to practical sample. Further, the smartphone-based colorimetric paper-based analytical device (c-PAD) made of simple materials could also detect α-glucosidase sensitively. The smartphone-based on-site detection provided a convenient, instrument-free and sensitive sensing method for α-glucosidase.


Assuntos
Boro , Colorimetria , Cobre , Smartphone , alfa-Glucosidases , Colorimetria/métodos , Cobre/química , alfa-Glucosidases/metabolismo , alfa-Glucosidases/química , Boro/química , Compostos de Nitrogênio/química , Limite de Detecção , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Humanos , Grafite
16.
Int J Mol Sci ; 25(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38732166

RESUMO

This current study assessed the impacts of morphology adjustment of perovskite BiFeO3 (BFO) on the construction and photocatalytic activity of P-infused g-C3N4/U-BiFeO3 (U-BFO/PCN) heterostructured composite photocatalysts. Favorable formation of U-BFO/PCN composites was attained via urea-aided morphology-controlled hydrothermal synthesis of BFO followed by solvosonication-mediated fusion with already synthesized P-g-C3N4 to form U-BFO/PCN composites. The prepared bare and composite photocatalysts' morphological, textural, structural, optical, and photocatalytic performance were meticulously examined through various analytical characterization techniques and photodegradation of aqueous rhodamine B (RhB). Ellipsoids and flakes morphological structures were obtained for U-BFO and BFO, and their effects on the successful fabrication of the heterojunctions were also established. The U-BFO/PCN composite exhibits 99.2% efficiency within 20 min of visible-light irradiation, surpassing BFO/PCN (88.5%), PCN (66.8%), and U-BFO (26.1%). The pseudo-first-order kinetics of U-BFO/PCN composites is 2.41 × 10-1 min-1, equivalent to 2.2 times, 57 times, and 4.3 times of BFO/PCN (1.08 × 10-1 min-1), U-BFO, (4.20 × 10-3 min-1), and PCN, (5.60 × 10-2 min-1), respectively. The recyclability test demonstrates an outstanding photostability for U-BFO/PCN after four cyclic runs. This improved photocatalytic activity exhibited by the composites can be attributed to enhanced visible-light utilization and additional accessible active sites due to surface and electronic band modification of CN via P-doping and effective charge separation achieved via successful composites formation.


Assuntos
Bismuto , Fotólise , Rodaminas , Catálise , Bismuto/química , Rodaminas/química , Luz , Compostos Férricos/química , Compostos de Nitrogênio/química , Titânio/química , Processos Fotoquímicos , Nitrilas/química , Cinética , Grafite , Óxidos , Compostos de Cálcio
17.
Bioorg Chem ; 147: 107418, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703441

RESUMO

A key approach in developing green chemistry involves converting solar energy into chemical energy of biomolecules through photocatalysis. Photocatalysis can facilitate the regeneration of nicotinamide cofactors during redox processes. Nicotinamide cofactor biomimetics (NCBs) are economical substitutes for natural cofactors. Here, photocatalytic regeneration of NADH and reduced NCBs (NCBsred) using graphitic carbon nitride (g-C3N4) was developed. The process involves g-C3N4 as the photocatalyst, Cp*Rh(bpy)H2O2+ as the electron mediator, and Triethanolamine as the electron donor, facilitating the reduction of NAD+ and various oxidative NCBs (NCBsox) under light irradiation. Notably, the highest reduction yield of 48.32 % was achieved with BANA+, outperforming the natural cofactor NAD+. Electrochemical analysis reveals that the reduction efficiency and capacity of cofactors relies on their redox potentials. Additionally, a coupled photo-enzymatic catalysis system was explored for the reduction of 4-Ketoisophorone by Old Yellow Enzyme XenA. Among all the NCBsox and NAD+, the highest conversion ratio of over 99 % was obtained with BANA+. After recycled for 8 times, g-C3N4 maintained over 93.6 % catalytic efficiency. The photocatalytic cofactor regeneration showcases its outstanding performance with NAD+ as well as NCBsox. This work significantly advances the development of photocatalytic cofactor regeneration for artificial cofactors and its potential application.


Assuntos
Biocatálise , Oxirredução , Processos Fotoquímicos , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Estrutura Molecular , NAD/química , NAD/metabolismo , Biomimética , Niacinamida/química , Niacinamida/metabolismo , Compostos de Nitrogênio/química , Grafite
18.
Environ Res ; 254: 119163, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38759770

RESUMO

The hydrothermal approach was used in the design and construction of the SnWO4 (SW) nanoplates anchored g-C3N4 (gCN) nanosheet heterostructures. Morphology, optical characteristics, and phase identification were investigated. The heterostructure architect construction and successful interface interaction were validated by the physicochemical characteristics. The test materials were used as a photocatalyst in the presence of visible light to break down the antibiotic tetracycline (TC) and the organic Rhodamine B (RhB). The best photocatalytic degradation efficiency of TC (97%) and RhB (98%) pollutants was demonstrated by the optimized 15 mg of gCNSW-7.5 in 72 and 48 min, respectively, at higher rate constants of 0.0409 and 0.0772 min-1. The interface contact between gCN and SW, which successfully enhanced charge transfer and restricted recombination rate in the photocatalyst, is responsible for the enhanced performance of the gCNSW heterostructure photocatalyst. In addition, the gCNSW heterostructure photocatalyst demonstrated exceptional stability and reusability over the course of four successive testing cycles, highlighting its durable and dependable function. Superoxide radicals and holes were shown to be key players in the degradation of contaminants through scavenger studies. The charge transfer mechanism in the heterostructure is identified as Z-scheme mode with the help of UV-vis DRS analysis. Attributed to its unique structural features, and effective separation of charge carriers, the Z-scheme gCNSW-7.5 heterostructure photocatalyst exhibits significant promise as an exceptionally efficient catalyst for the degradation of pollutants. This positions it as a prospective material with considerable potential across various environmental applications.


Assuntos
Luz , Rodaminas , Tetraciclina , Rodaminas/química , Tetraciclina/química , Catálise , Poluentes Químicos da Água/química , Fotólise , Compostos de Nitrogênio/química , Processos Fotoquímicos , Antibacterianos/química , Grafite
19.
Anal Chem ; 96(23): 9704-9712, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38819721

RESUMO

Due to the commonly low content of biomarkers in diseases, increasing the sensitivity of electrochemiluminescence (ECL) systems is of great significance for in vitro ECL diagnosis and biodetection. Although dissolved O2 (DO) has recently been considered superior to H2O2 as a coreactant in the most widely used luminol ECL systems owing to its improved stability and less biotoxicity, it still has unsatisfactory ECL performance because of its ultralow reactivity. In this study, an effective plasmonic luminol-DO ECL system has been developed by complexing luminol-capped Ag nanoparticles (AgNPs) with plasma-treated Fe single-atom catalysts (Fe-SACs) embedded in graphitic carbon nitride (g-CN) (pFe-g-CN). Under optimal conditions, the performance of the resulting ECL system could be markedly increased up to 1300-fold compared to the traditional luminol-DO system. Further investigations revealed that duple binding sites of pFe-g-CN and plasmonically induced hot holes that disseminated from AgNPs to g-CN surfaces lead to facilitate significantly the luminous reaction process of the system. The proposed luminol-DO ECL system was further employed for the stable and ultrasensitive detection of prostate-specific antigen in a wide linear range of 1.0 fg/mL to 1 µg/mL, with a pretty low limit of detection of 0.183 fg/mL.


Assuntos
Técnicas Eletroquímicas , Ferro , Medições Luminescentes , Luminol , Nanopartículas Metálicas , Oxigênio , Prata , Luminol/química , Catálise , Oxigênio/química , Nanopartículas Metálicas/química , Ferro/química , Prata/química , Humanos , Antígeno Prostático Específico/metabolismo , Antígeno Prostático Específico/química , Grafite/química , Limite de Detecção , Domínio Catalítico , Compostos de Nitrogênio/química
20.
Chemosphere ; 360: 142399, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38801903

RESUMO

Herin, a new nanohybrid acid catalyst was fabricated for the efficient biodiesel production. At the first, magnetic porous nanosheets of graphitic carbon nitride (g-C3N4@Fe3O4) was prepared and then functionalized with sulfonic acid. Next, the preparation of the catalyst was completed by mixing this surface modified support with n-methyl imidazolium butyl sulfonate zwitterion to achieve non-covalent immobilized acidic ionic liquid on g-C3N4@Fe3O4 support. The catalyst underwent characterization through various techniques such as 1H and 13C NMR, FTIR, SEM, TEM, TGA, EDX and BET which revealing that the magnetic support loaded acidic ionic liquids via a robust charge interaction effect enabling the one-pot production of biodiesel from low-quality oils. Furthermore, the catalyst could be simply recovered using a permanent magnet and reused multiple times without a significant decline in catalytic activity. Consequently, the solid catalyst based on ionic liquids holds promise for the sustainable and eco-friendly production of biodiesel from low-quality oils. Furthermore, Response Surface Methodology (RSM) and Artificial Neural Networks (ANN) were used to model the yield and various process parameters. The findings underscore the enhanced predictive capabilities of ANN in comparison to RSM.


Assuntos
Biocombustíveis , Grafite , Líquidos Iônicos , Redes Neurais de Computação , Líquidos Iônicos/química , Catálise , Grafite/química , Compostos de Nitrogênio/química
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