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1.
Chemosphere ; 353: 141544, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38408573

RESUMO

Meeting societal demand for potable water supply remains one of the prioritized challenges faced in the modern era. The anthropogenic intervention has led to a dire situation threatening ecological balance and human health. There is an inevitable need for the development of new technologies and innovations in existing technologies for water treatment. Photocatalytic Membrane technology, encompassing the merits of membrane filtration and photocatalytic degradation has evolved as a potential and reliable technology for sustainable water treatment. Innovations in photocatalytic materials and membrane fabrication techniques can lead to the goal of commercialization of membrane water treatment technology. Herein, we demonstrate the potential of graphitic carbon nitride (g-C3N4) and its functionalized analog as photocatalytic membranes for sustainable water treatment. g-C3N4 and Tetracarboxyphenylporphyrin sensitized g-C3N4 (g-C3N4/TCPP) was introduced onto commercial nylon membrane surface via a layer-by-layer (LBL) assembly method using chitosan and sodium salt of polystyrene sulphonic acid as polyelectrolytes. The fabricated membranes were characterized to ensure the integration of the photocatalysts. The performance of the membranes for water treatment was assessed by selecting some common dyes as model pollutants. The modified membranes exhibited excellent flux recovery and could afford high rejection rates upon irradiation indicating the prospects for sustainable filtration.


Assuntos
Grafite , Purificação da Água , Humanos , Grafite/efeitos da radiação , Compostos de Nitrogênio , Purificação da Água/métodos , Catálise
2.
Chemosphere ; 352: 141511, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38401862

RESUMO

The surface hydrophilicity of a photocatalyst is an important factor that directly influences its interactions with organic pollutants and significantly impacts its degradation. In this study, we investigated the impact of increased hydrophilicity of g-C3N4 (CN) by alkaline solvothermal treatment on the degradations of three antibiotics (oxytetracycline (OTC), oxolinic acid (OA), and sulfamethoxazole (SMX)) with different log Kow values. Scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), and Fourier-transform infrared (FT-IR) spectroscopy showed no significant differences in the morphology, crystalline structure, and surface functional groups of CN after alkaline solvothermal treatment (Nv-HPCN). However, contact angle analysis revealed that Nv-HPCN (31.8°) was more hydrophilic than CN (61.1°). To assess the hydrophilicity of the antibiotics, the log Kow values of SMX (0.77), OA (0.43), and OTC (-0.34) were measured. Nv-HPCN showed faster OTC degradation than CN, whereas the opposite pattern was observed for the degradation of OA. Scavenger tests showed that O2•- and h+ mainly contributed to the degradation of these antibiotics. Furthermore, the influences of NOM and coexisting anions on antibiotic degradation were investigated. This study thus offers perspectives on the impact of surface hydrophilicity of photocatalysts on the degradation of antibiotics.


Assuntos
Grafite , Compostos de Nitrogênio , Oxitetraciclina , Antibacterianos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Oxitetraciclina/química , Grafite/química , Catálise
3.
Chemosphere ; 352: 141352, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307332

RESUMO

Benzopyrene (BaP) stands as a potent polycyclic aromatic hydrocarbon (PAH) molecule, boasting five fused aromatic rings, making its way into the human food chain through soil contamination. The persistent environmental presence of PAHs in soil, attributed to industrial exposure, is primarily due to their low molecular weight and hydrophobic nature. To preemptively address the entry of BaP into the food chain, the application of nanocomposites was identified as an effective remediation strategy. Post-synthesis, comprehensive characterization tests employing techniques such as UV-DRS, XRD, SEM-EDX, FTIR, and DLS unveiled the distinctive features of the g-C3N4-SnS nanocomposites. These nanocomposites exhibited spherical shapes embedded on layers of nanosheets, boasting particle diameters measuring 88.9 nm. Subsequent tests were conducted to assess the efficacy of eliminating benzopyrene from a combination of PAH molecules and g-C3N4-SnS nanocomposites. Varied parameters, including PAH concentration, adsorbent dosage, and suspension pH, were systematically explored. The optimized conditions for the efficient removal of BaP utilizing the g-C3N4-SnS nanocomposite involved 2 µg/mL of benzopyrene, 10 µg/mL of the nanocomposite, and a pH of 5, considering UV light as the irradiation source. The investigation into the mechanism governing BaP elimination closely aligned with batch adsorption results involved a thorough exploration of adsorption kinetics and isotherms. Photocatalytic degradation of benzopyrene was achieved, reaching a maximum of 86 % in 4 h and 36 % in 2 h, with g-C3N4-SnS nanocomposite acting as the catalyst. Further validation through HPLC data confirmed the successful removal of BaP from the soil matrix.


Assuntos
Grafite , Nanocompostos , Compostos de Nitrogênio , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Nanocompostos/química , Grafite/química , Benzo(a)pireno , Benzopirenos , Solo , Catálise
4.
Chemosphere ; 346: 140551, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303398

RESUMO

The synthesis and characterization of graphitic carbon nitride (GCN) and its composites with calcined layered double hydroxide (CLDH) were examined in this investigation. The goal was to assess these composites' maximum adsorption capacity (qmax) for U(VI) ions in wastewater. Several different characterization methodologies were utilized to examine the fabricated substances. These methods encompass X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The GCN-CLDH composite displayed enhanced adsorption ability towards U(VI) ions due to its high surface functionality. Langmuir adsorption isotherm analysis showed that more than 99% of U(VI) ions were adsorbed, with a qmax of 196.69 mg/g. The kinetics data exhibited a good fit for a pseudo-second-order (PSO) model. Adsorption mechanisms involving precipitation and surface complexation via Lewis's acid-base interactions were proposed. The application of the GCN-CLDH composite in groundwater demonstrated adsorption below the maximum permissible limit established by USEPA, indicating improved cycling stability. These observations underscore the capacity of the GCN-CLDH composite's proficiency in adsorbing U(VI) aqueous solutions containing radioactive metals.


Assuntos
Grafite , Compostos de Nitrogênio , Poluentes Químicos da Água , Água , Espectroscopia de Infravermelho com Transformada de Fourier , Hidróxidos/química , Adsorção , Cinética , Poluentes Químicos da Água/análise
5.
J Environ Sci (China) ; 141: 287-303, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38408829

RESUMO

Graphitic carbon nitride with nanorod structure (Nr-GCN) was synthesized using melamine as a precursor without any other reagents by hydrothermal pretreatment method. XRD, FTIR, SEM, N2 adsorption-desorption from BET, UV-Vis DRS spectroscopy, and photoluminescence were used to characterize the prepared samples. Also, the photoelectrochemical behavior of nanoparticles was studied by photocurrent transient response and cyclic voltammetry analysis. Polystyrene (PS) fibrous mat was fabricated by electrospinning technique and used as a support for the stabilization of the nanoparticles. The performance of the synthesized nanoparticles and photocatalytic fibers (PS/Nr-GCN) was evaluated in oilfield-produced water treatment under visible light irradiation. During this process, oil contaminants were adsorbed by hydrophobic polystyrene fibers and simultaneously degraded by Nr-GCN. The removal efficiency of chemical oxygen demand (COD) has been obtained 96.6% and 98.4% by Nr-GCN and PS/Nr-GCN, respectively, at the optimum conditions of pH 4, photocatalyst dosage 0.5 g/L, COD initial concentration 550 mg/L, and illumination time 150 min. The gas chromatography-mass spectroscopy analysis results showed 99.3% removal of total petroleum hydrocarbons using photocatalytic fibers of PS/Nr-GCN. The results demonstrated that the GCN has outstanding features like controllable morphology, visible-light-driven, and showing high potential in oily wastewater remediation. Moreover, the synergistic effect of adsorption and photocatalytic degradation is an effective technique in oilfield-produced water treatment.


Assuntos
Grafite , Nanotubos , Compostos de Nitrogênio , Poliestirenos , Adsorção , Campos de Petróleo e Gás
6.
ACS Appl Bio Mater ; 7(3): 1579-1587, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38386014

RESUMO

In this study, a nanocomposite was synthesized by incorporating graphitic carbon nanosheets, carboxyl-functionalized multiwalled carbon nanotubes, and zirconium oxide nanoparticles. The resulting nanocomposite was utilized for the modification of a glassy carbon electrode. Subsequently, matrix metalloproteinase aptamer (AptMMP-9) was immobilized onto the electrode surface through the application of ethyl-3-(3-(dimethylamino)propyl)carbodiimide hydrochloride-N-hydroxysuccinimide (EDC-NHS) chemistry. Morphological characterization of the nanomaterials and the nanocomposite was performed using field-emission scanning electron microscopy (FESEM). The nanocomposite substantially increased the electroactive surface area by 205%, facilitating enhanced immobilization of AptMMP-9. The efficacy of the biosensor was evaluated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Under optimal conditions, the fabricated sensor demonstrated a broad range of detection from 50 to 1250 pg/mL with an impressive lower limit of detection of 10.51 pg/mL. In addition, the aptasensor exhibited remarkable sensitivity, stability, excellent selectivity, reproducibility, and real-world applicability when tested with human serum and saliva samples. In summary, our developed aptasensor exhibits significant potential as an advanced biosensing tool for the point-of-care quantification of MMP-9, promising advancements in biomarker detection for practical applications.


Assuntos
Aptâmeros de Nucleotídeos , Grafite , Nanocompostos , Nanotubos de Carbono , Compostos de Nitrogênio , Zircônio , Humanos , Nanotubos de Carbono/química , Metaloproteinase 9 da Matriz , Técnicas Eletroquímicas/métodos , Saliva , Reprodutibilidade dos Testes , Limite de Detecção , Aptâmeros de Nucleotídeos/química , Nanocompostos/química
7.
ACS Appl Bio Mater ; 7(3): 1910-1924, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38391158

RESUMO

Creating polymers that combine various functions within a single system expands the potential applications of such polymeric materials. However, achieving polymer materials that possess simultaneously elevated strength, toughness, and self-healing capabilities, along with special properties, remains a significant challenge. The present study demonstrates the preparation of S and Mo codoped graphitic carbon nitride (g-C3N4) (Mo@S-CN) nanohybrid and the fabrication of self-healing waterborne polyurethane (SHWPU)/Mo@S-CN (SHWPU/NS) nanocomposites for advanced applications. Mo@S-CN is an intriguing combination of g-C3N4 nanosheets and molybdenum oxide (MoOx) nanorods, forming a complex lamellar structure. This unique arrangement significantly improves the inborn properties of SHWPU to an impressive degree, especially mechanical strength (28.37-34.11 MPa), fracture toughness (73.65-140.98 MJ m-2), and thermal stability (340.17-348.01 °C), and introduces fluorescence activity into the matrix. Interestingly, a representative SHWPU/NS0.5 film is so tough that a dumbbell of 15 kg, which is 53,003 times heavier than the weight of the film, can be successfully lifted without any significant crack. Remarkably, fluorescence activity is developed because of electronic excitations occurring within the repeating polymeric tris-triazine units of the Mo@S-CN nanohybrid. This fascinating feature was effectively harnessed by assessing the usability of aqueous dispersions of the Mo@S-CN nanohybrid and photoluminescent SHWPU/NS nanocomposites as sustainable stains for bioimaging of human dermal fibroblast cells and anticounterfeiting materials, respectively. The in vitro fluorescence tagging test showed blue emission from 365 nm excitation, green emission from 470 nm excitation, and red emission from 545 nm excitation. Most importantly, in vitro hemocompatibility assessment, in vitro cytocompatibility, cell proliferation assessment, and cellular morphology assessment supported the biocompatibility nature of the Mo@S-CN nanohybrid and SHWPU/NS nanocomposites. Thus, these materials can be used for advanced applications including bioimaging.


Assuntos
Grafite , Nanocompostos , Compostos de Nitrogênio , Poliuretanos , Humanos , Proliferação de Células , Eletrônica , Nanocompostos/toxicidade , Polímeros
8.
Environ Geochem Health ; 46(3): 76, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38367100

RESUMO

The escalating global industrial expansion has led to the extensive release of organic compounds into water bodies, resulting in substantial pollution and posing severe threats to both human health and the ecosystem. Among common micropollutants, bisphenol A (MP-BA) has emerged as a significant endocrine-disrupting chemical with potential adverse effects on human health and the environment. This study aims to develop an efficient photocatalyst, specifically by incorporating palladium-doped graphitic carbon nitride (Pd@GCN), to eliminate MP-BA pollutants present in industrial wastewater. The examination of optical properties and photoluminescence indicates that incorporating Pd into GCN enhances the visible light absorption spectra, which extends beyond 570 nm, and accelerates the separation rate of electron-hole pairs. The photocatalytic degradation efficiency of MP-BA increases from 81.7 to 98.8% as the solution pH rises from 5.0 to 9.0. Moreover, Pd@GCN significantly improves the removal rate of MP-BA in wastewater samples, reaching an impressive 92.8% after 60 min of exposure to solar light. Furthermore, the Pd@GCN photocatalyst exhibits notable reusability over six cycles of MP-BA degradation, indicating its promising potential for the treatment of organic pollutants in wastewater under solar light conditions.


Assuntos
Poluentes Ambientais , Grafite , Compostos de Nitrogênio , Fenóis , Águas Residuárias , Humanos , Paládio , Ecossistema , Compostos Benzidrílicos
9.
J Hazard Mater ; 467: 133715, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38359763

RESUMO

Paraquat (PQ) is a widely used and harmful herbicide that must be detected in the environment. This study reports a novel composite (CoS2-GCN) prepared by assembling cobalt disulfide (CoS2) derived from metal-organic frameworks (MOFs) on graphitic carbon nitride (GCN). An electrochemical sensor (CoS2-GCN/ glassy carbon electrode (GCE)) was successfully prepared by modifying CoS2-GCN onto a GCE to sensitively detect PQ. Different concentrations of PQ were detected using square-wave voltammetry, and the CoS2-GCN/GCE electrochemical sensor showed remarkable response signals for PQ in the range of 20 - 1000 nM and 1 - 13 µM, with a detection limit of 4.13 nM (S/N = 3). The CoS2-GCN/GCE electrochemical sensor exhibited high stability, reproducibility, and immunity to interference, which were attributed to the synergistic effects of CoS2 and GCN. In addition, the CoS2-GCN/GCE electrochemical sensor showed high applicability for the analysis of fruit samples. Therefore, the proposed sensor has potential applications in PQ detection.


Assuntos
Frutas , Grafite , Compostos de Nitrogênio , Paraquat , Paraquat/análise , Reprodutibilidade dos Testes , Frutas/química , Limite de Detecção
10.
Environ Pollut ; 345: 123556, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38346635

RESUMO

The direct thermal polymerization techniques were applied to prepare the graphene oxide (GO)-graphitic carbon nitride (gCN) hybrid structure. The prepared hybrid heterojunction GO-gCN nanosheets were utilized as a photocatalyst to remove model pollutants methylene blue (MB) dye. The basic physio-chemical properties of GO-gCN layered materials have been analyzed by various characterization techniques. In addition, the proposed materials have a higher photocatalytic ability toward the degradation of aqueous solution of MB dye under visible light irradiation within a short treatment time. This is because it's the synergistic effects of GO-gCN layer-by-layer structures produced by π─π stacking with charge-transfer interactions. The gCN with GO composite can able to enhance the charge transfer and light-harvesting properties. Under the influence of photocatalyst, the surface of Graphene oxide undergoes the separation and combination of carbonyl radicals, hydroxyl radicals, epoxy radicals, and electron-hole pairs. This enhances the absorption of visible light and improves the degradation of MB, when GO is incorporated into gCN. The removal efficiency of MB reached up to 82.311% within the short treatment time.


Assuntos
Grafite , Azul de Metileno , Compostos de Nitrogênio , Elétrons
11.
Bioresour Technol ; 397: 130476, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387842

RESUMO

The use of solar energy and heterotrophic microbes to synthesize microbial lipids is a promising strategy to solve energy crisis and reduce CO2 emissions. In this study, a photocatalyst, oxygen-doped graphitic carbon nitride (O-g-C3N4), was synthesized and combined with an oleaginous yeast strain, Cutaneotrichosporon dermatis ZZ-46, to construct a photocatalyst-microbe hybrid (PMH) system. Under illumination, the lipid yield of the PMH system reached 1.61 g/L after 96 h (87 % higher than that of control). NADPH/NADP+ ratio of ZZ-46 cells in the PMH system increased. Metabolomics results revealed that glutathione generation was increased, and the fatty acid decomposition pathway in ZZ-46 cells was inhibited in the PMH system. This study provides a new approach for the synthesis of microbial lipids based on solar energy and heterotrophic microbes.


Assuntos
Grafite , Luz , Compostos de Nitrogênio , Oxigênio , Catálise , Lipídeos
12.
Sci Total Environ ; 917: 170357, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38286286

RESUMO

The proliferation of harmful algal blooms is a global concern due to the risk they pose to the environment and human health. Algal toxins which are hazardous compounds produced by dangerous algae, can potentially kill humans. Researchers have been drawn to photocatalysis because of its clean and energy-saving properties. Graphite carbon nitride (g-C3N4) photocatalysts have been extensively studied for their ability to eliminate algae. These photocatalysts have attracted notice because of their cost-effectiveness, appropriate electronic structure, and exceptional chemical stability. This paper reviews the progress of photocatalytic inactivation of harmful algae by g-C3N4-based materials in recent years. A brief overview is given of a number of the modification techniques on g-C3N4-based photocatalytic materials, as well as the process of inactivating algal cells and destroying their toxins. Additionally, it provides a theoretical framework for future research on the eradication of algae using g-C3N4-based photocatalytic materials.


Assuntos
Grafite , Microcystis , Humanos , Grafite/química , Catálise , Compostos de Nitrogênio
13.
Chemosphere ; 351: 141218, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266876

RESUMO

The widespread consumption of pharmaceutical drugs and their incomplete breakdown in organisms has led to their extensive presence in aquatic environments. The indiscriminate use of antibiotics, such as sulfonamides, has contributed to the development of drug-resistant bacteria and the persistent pollution of water bodies, posing a threat to human health and the safety of the environment. Thus, it is paramount to explore remediation technologies aimed at decomposing and complete elimination of the toxic contaminants from pharmaceutical wastewater. The review aims to explore the utilization of metal-oxide nanoparticles (MONPs) and graphitic carbon nitrides (g-C3N4) in photocatalytic degradation of sulfonamides from wastewater. Recent advances in oxidation techniques such as photocatalytic degradation are being exploited in the elimination of the sulfonamides from wastewater. MONP and g-C3N4 are commonly evolved nano substances with intrinsic properties. They possessed nano-scale structure, considerable porosity semi-conducting properties, responsible for decomposing wide range of water pollutants. They are widely applied for photocatalytic degradation of organic and inorganic substances which continue to evolve due to the low-cost, efficiency, less toxicity, and more environmentally friendliness of the materials. The review focuses on the current advances in the application of these materials, their efficiencies, degradation mechanisms, and recyclability in the context of sulfonamides photocatalytic degradation.


Assuntos
Grafite , Nanopartículas Metálicas , Compostos de Nitrogênio , Óxidos , Humanos , Sulfonamidas , Águas Residuárias , Sulfanilamida , Preparações Farmacêuticas , Catálise
14.
Food Chem ; 442: 138497, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38271904

RESUMO

The production of sustainable materials with properties aimed at the additive manufacturing of electrochemical sensors has gained prestige in the scientific scenario. Here, a novel lab-made composite material using graphite (G) and carbon nitride (C3N4) embedded into polylactic acid (PLA) biopolymer is proposed to produce 3D-printed electrodes. PLA offers printability and mechanical stability in this composition, while G and C3N4 provide electrical properties and electrocatalytic sites, respectively. Characterizations by Raman and infrared spectroscopies and Energy Dispersive X-rays indicated that the G/C3N4/PLA composite was successfully obtained, while electron microscopy images revealed non-homogeneous rough surfaces. Better electrochemical properties were achieved when the G/C3N4/PLA proportion (35:5:60) was used. As a proof of concept, amaranth (AMR), a synthetic dye, was selected as an analyte, and a fast method using square wave voltammetry was developed. Utilizing the 3D-printed G/C3N4/PLA electrode, a more comprehensive linear range (0.2 to 4.2 µmol/L), a 5-fold increase in sensitivity (9.83 µmol-1 L µA), and better limits of detection (LOD = 0.06 µmol/L) and quantification (LOQ = 0.18 µmol/L) were achieved compared to the G/PLA electrode. Samples of jelly, popsicles, isotonic drinks, and food flavoring samples were analyzed, and similar results to those obtained by UV-vis spectrometry confirmed the method's reliability. Therefore, the described sensor is a simple, cost-effective alternative for assessing AMR in routine food analysis.


Assuntos
Amaranthus , Grafite , Nitrilas , Compostos de Nitrogênio , Corante Amaranto , Reprodutibilidade dos Testes , Eletrodos , Poliésteres , Impressão Tridimensional , Técnicas Eletroquímicas
15.
J Colloid Interface Sci ; 661: 68-82, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38295704

RESUMO

Improving the activation capacity of peroxymonosulfate (PMS) to increase radical and non-radical production is critical for antibiotic degradation. However, how to boost reactive oxygen species (ROS) and speed interfacial charge transfer remains an essential challenge. We report a coupling system of 10 %CNNS/CuBi2O4 photocatalyst and sulfate radical-based advanced oxidation processes (SO4--AOPs) to enhance the activation of PMS and improve antibiotic degradation. Owing to highly efficient oxygen activation and interfacial charge transfer, the degradation efficiency of the photo-assisted PMS system was as high as 51.6 times and 2.8 times that of photocatalyst and SO4--AOPs alone, respectively. Importantly, the highly efficient oxygen activation resulted in the production of O2-, which in turn could utilize the excess electrons generated through efficient interfacial charge transfer to convert into non-radical 1O2. The total organic carbon (TOC) elimination effectiveness of the photo-assisted PMS system reached 82 % via the synergy of radicals and non-radicals (O2-, OH, 1O2, SO4-, h+). This system also had excellent potential for reducing the generation and toxicity of disinfection by-products (DBPs), as evidenced through significant reductions in concentrations of trichloromethane (TCM), dichloroacetic acid (DCAA), and trichloronitromethane (TCNM) by 76 %, 64 %, and 35 %, respectively, providing an effective and eco-friendly strategy for antibiotic treatment.


Assuntos
Grafite , Compostos de Nitrogênio , Oxigênio , Peróxidos , Antibacterianos
16.
Chem Res Toxicol ; 37(1): 72-80, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38176075

RESUMO

Fabrication of a metal-organic framework-based photocatalyst has been gaining much interest due to its higher surface area and reasonable band gap, enhancing its photocatalytic activity. This study attempted a facile synthesis of the hybrid photocatalyst UiO-66 doped with graphitic carbon nitride (GCN) by a simple solvothermal method. This composite minimized the drawback related to photogenerated charge transfer and recombination and helped the absorption of visible light. The material was investigated by using various instrumental techniques. In this work, ciprofloxacin (CIP), a fluoroquinolone drug, was chosen as a target micropollutant, and a photodegradation experiment was carried out by using UiO-66, GCN, and UiO-66/GCN under a visible light source, which exhibited 81.85, 69.48, and 93.60% of degradation, respectively. Finally, liquid chromatography mass spectrometry analysis and theoretical computation were carried out to identify the CIP degradation mechanism, and T.E.S.T. software was used to investigate the toxicity of the intermediate products. Apart from photocatalytic activity, the prepared material was also tested for its antibacterial properties against Staphylococcus aureus and Escherichia coli.


Assuntos
Ciprofloxacina , Grafite , Estruturas Metalorgânicas , Compostos de Nitrogênio , Ácidos Ftálicos , Ciprofloxacina/farmacologia , Antibacterianos/farmacologia , Escherichia coli , Luz
17.
Food Chem ; 441: 138405, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38218142

RESUMO

Flavonoids or phenolic compounds are part of the daily intake of every human being. Though they are positive traders for metabolism, excessive intakes bring about detrimental impacts on human health. Herein, the anti-cancer capacitive nature quercetin (Qc) was electrochemically detected through the rare earth metal-based sphere like praseodymium vanadate (PrVO4) entrapped graphitic carbon nitride (g-CN) as electrode modifiers. The nanocomposite was prepared by the one-pot hydrothermal method and characterized by phase compositional and morphology-based techniques. The existing synergistic nature between the PrV@g-CN (praseodymium vanadate@graphitic carbon nitride) makes them have an enhanced electrochemical response towards the Qc than the individual material. The obtained cyclic voltammogram and differential pulse voltammogram profile show one major oxidation peak which is attributed to the conversion of quercetin to quercetin-o-quinone. The PrV@g-CN/GCE (GCE- glassy carbon electrode) shows a good electrochemical active surface area (A = 110 cm2) and linear range between 0.05 and 252.00 µM with a LOD (limit of detection) of 0.002 µM. Moreover, the PrV@g-CN/GCE exhibits good current retention (94.76 %) around 14 days and appreciable repeatability (RSD- 0.5 %) and reproducibility (RSD- 1.3 %) towards the Qc. The real-time implementation of the proposed sensor exhibits a good recovery range towards the black tea (95.00-98.10 %) and green tea (97.80-99.60 %).


Assuntos
Grafite , Nanocompostos , Compostos de Nitrogênio , Quercetina , Humanos , Flavonoides , Praseodímio , Vanadatos/química , Reprodutibilidade dos Testes , Limite de Detecção , Técnicas Eletroquímicas/métodos , Carbono/química , Eletrodos , Nanocompostos/química
18.
Biomater Adv ; 157: 213737, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211506

RESUMO

Graphitic carbon nitride (g-C3N4) is explored as a novel sustainable visible light photoinitiator for the preparation of biomimetic 3D hydrogel scaffolds comprising gelatin methacrylamide (GelMA) and dopamine methacrylamide for use in tissue engineering. The initiator efficiency was assessed by comparing the swelling behavior and the stability of photopolymerized hydrogels prepared with GelMA of different degrees of functionalization and different comonomer compositions. Bioactive composite hydrogels with a 50 wt% nanohydroxyapatite (nHAp) content, to closely mimic the actual bone composition, were successfully obtained by the introduction of nHAp in the prepolymer solutions followed by photopolymerization. The composite hydrogels demonstrated enhanced mechanical properties and excellent stability in PBS verifying the preparation of robust 3D scaffolds for use in cancellous or pre-calcified bone tissue engineering applications. The in vitro cell response of the composite scaffolds exhibited high cell viability and enhanced differentiation of pre-osteoblasts to mature osteoblasts, demonstrating their osteogenic potential. This work establishes, for the first time, the excellent properties of g-C3N4 as a sustainable, visible light initiator, fully satisfying the principles of green chemistry, for the preparation of robust and biologically relevant hydrogels, and proposes a new approach to overcome the main challenges of conventional photoinitiators in cell scaffold fabrication, such as photobleaching, high cost and non-scalable synthesis employing toxic organic precursors and solvents.


Assuntos
Acrilamidas , Biomimética , Grafite , Compostos de Nitrogênio , Pirenos , Engenharia Tecidual , Luz , Hidrogéis
19.
Appl Microbiol Biotechnol ; 108(1): 105, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38204134

RESUMO

This review presents an analysis of formamide, focussing on its occurrence in nature, its functional roles, and its promising applications in the context of the bioeconomy. We discuss the utilization of formamide as an innovative nitrogen source achieved through metabolic engineering. These approaches underscore formamide's potential in supporting growth and production in biotechnological processes. Furthermore, our review illuminates formamide's role as a nitrogen source capable of safeguarding cultivation systems against contamination in non-sterile conditions. This attribute adds an extra layer of practicality to its application, rendering it an attractive candidate for sustainable and resilient industrial practices. Additionally, the article unveils the versatility of formamide as a potential carbon source that could be combined with formate or CO2 assimilation pathways. However, its attributes, i.e., enriched nitrogen content and comparatively limited energy content, led to conclude that formamide is more suitable as a co-substrate and that its use as a sole source of carbon for biomass and bio-production is limited. Through our exploration of formamide's properties and its applications, this review underscores the significance of formamide as valuable resource for a large spectrum of industrial applications. KEY POINTS: • Formidases enable access to formamide as source of nitrogen, carbon, and energy • The formamide/formamidase system supports non-sterile fermentation • The nitrogen source formamide supports production of nitrogenous compounds.


Assuntos
Formamidas , Nitrogênio , Compostos de Nitrogênio , Carbono
20.
Chemosphere ; 350: 141122, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38184078

RESUMO

A few PAHs (polycyclic aromatic hydrocarbons) which are known to be pervasive and are of high priority are found to be detrimental pollutants having high potential in the destruction of the network. Hence, photocatalytic disintegration of these PAHs, namely benzo [a]pyrene, found in water is explored. A novel nanocomposite of Ag-Ni on g-C3N4 was fabricated. The prepared nanocomposites were characterized by techniques like UV, XRD, SEM-EDAX, FTIR, and DLS to understand their nature. The activity of the same as a catalyst in the deterioration of the benzopyrene molecule in water was investigated under different conditions including change in the concentration of the PAH, dosage of the catalyst prepared, pH of the reaction mixture, and by changing the source of irradiation. In addition, antibacterial analysis of the prepared nanocomposite material was conducted to determine whether it could be applied to environmental cleanup strategies of high quality.


Assuntos
Grafite , Nanocompostos , Compostos de Nitrogênio , Hidrocarbonetos Policíclicos Aromáticos , Prata/química , Benzo(a)pireno , Níquel , Luz , Antibacterianos/farmacologia , Antibacterianos/química , Nanocompostos/química , Água , Catálise
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