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1.
Luminescence ; 39(5): e4758, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38712530

RESUMEN

The ability of heterogeneous photocatalysis to effectively remove organic pollutants from wastewater has shown great promise as a tool for environmental remediation. Pure zinc ferrites (ZnFe2O4) and magnesium-doped zinc ferrites (Mg@ZnFe2O4) with variable percentages of Mg (0.5, 1, 3, 5, 7, and 9 mol%) were synthesized via hydrothermal route and their photocatalytic activity was checked against methylene blue (MB) taken as a model dye. FTIR, XPS, BET, PL, XRD, TEM, and UV-Vis spectroscopy were used for the identification and morphological characterization of the prepared nanoparticles (NPs) and nanocomposites (NCs). The 7% Mg@ZnFe2O4 NPs demonstrated excellent degradation against MB under sunlight. The 7% Mg@ZnFe2O4 NPs were integrated with diverse contents (10, 50, 30, and 70 wt.%) of S@g-C3N4 to develop NCs with better activity. When the NCs were tested to degrade MB dye, it was revealed that the 7%Mg@ZnFe2O4/S@g-C3N4 NCs were more effective at utilizing solar energy than the other NPs and NCs. The synergistic effect of the interface formed between Mg@ZnFe2O4 and S@g-C3N4 was primarily responsible for the boosted photocatalytic capability of the NCs. The fabricated NCs may function as an effective new photocatalyst to remove organic dyes from wastewater.


Asunto(s)
Compuestos Férricos , Azul de Metileno , Compuestos de Nitrógeno , Energía Solar , Contaminantes Químicos del Agua , Zinc , Catálisis , Contaminantes Químicos del Agua/química , Compuestos Férricos/química , Azul de Metileno/química , Zinc/química , Magnesio/química , Fotólisis , Procesos Fotoquímicos , Colorantes/química , Nanocompuestos/química , Grafito/química , Aguas Residuales/química , Nitrilos/química
2.
Bioresour Technol ; 401: 130712, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38641300

RESUMEN

The growing interest in utilizing lignin for dye removal has gained momentum, but there is limited information on the intricate relationship between lignin structural characteristics and adsorption efficacy, especially for its biochar derivatives. This study focused on three types of lignin and their corresponding biochar derivatives. Among them, ZnCl2-activated acidic/alkali densified lignin preparation of lignin-derived active carbon exhibited superior adsorption performance, achieving 526.32 mg/g for methylene blue and 2156.77 mg/g for congo red. Its exceptional adsorption capacity was attributed to its unique structural properties, including low alkyl and O-alkyl group content and high aromatic carbon levels. Furthermore, the adsorption mechanisms adhered to pseudo-second-order kinetics and the Langmuir model, signifying a spontaneous process. Intriguingly, lignin-derived active carbon also demonstrated remarkable recovery capabilities. These findings provide valuable insights into the impact of structural attributes on lignin and its biochar's adsorption performance.


Asunto(s)
Carbón Orgánico , Lignina , Lignina/química , Adsorción , Carbón Orgánico/química , Cinética , Azul de Metileno/química , Rojo Congo/química
3.
Chemosphere ; 357: 141982, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38608778

RESUMEN

Powdered activated carbon (PAC) has been extensively used as an effective adsorbent. Despite its excellent adsorption ability, PAC has drawbacks, including difficulty in filtration and reactivation after use, limitations of mass transfer in deeper areas because of its aggregated powder form, and limited applicability in high-flow systems. To overcome these limitations, we used a three-dimensional (3D) printing system to fabricate PAC into a 3D structure. Spectral and microscopic analyses indicated that PAC was embedded into 3D monolith and exhibited high porosity suitable for facile mass transfer. The designed 3D PAC filter effectively removed 200 ppm-methylene blue (MB) within 8 h and showed an adsorption efficiency of 93.4 ± 0.9%. The adsorption of MB onto the 3D PAC filter was described by the pseudo-first-order kinetic and Freundlich isotherm models. The negatively charged 3D PAC filter might attract the positively charged MB, thus favoring the physical adsorption of MB onto the 3D PAC filter. The adsorption performance of the 3D PAC filter was tested at various pH levels of 4-10 and against MB spiked in seawaters and freshwaters to evaluate its feasibility for use in real environments. Finally, the reproducibility and reusability of the 3D PAC filter were demonstrated through repeated adsorption and desorption processes against MB.


Asunto(s)
Carbón Orgánico , Colorantes , Azul de Metileno , Impresión Tridimensional , Contaminantes Químicos del Agua , Purificación del Agua , Carbón Orgánico/química , Adsorción , Colorantes/química , Contaminantes Químicos del Agua/química , Azul de Metileno/química , Purificación del Agua/métodos , Polvos , Cinética , Cationes/química , Filtración/métodos , Porosidad , Carbono/química , Concentración de Iones de Hidrógeno
4.
Int J Biol Macromol ; 267(Pt 1): 131432, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38583849

RESUMEN

The potential applications of cellulose nanofibril-based foam materials can be expanded by their enhanced water durability. This study proposes two crosslinking methods to improve the water durability of the oven-dried carboxymethylated cellulose nanofibril (CMCNF) foam. The first method involves the addition of a crosslinker, polyamideamine epichlorohydrin. The second method is the self-crosslinking of CMCNFs via heat treatment at 140 °C for less than an hour, which is a simple way to crosslink CMCNF-based materials. Both crosslinking methods resulted in excellent water durability and wet resilience of the foams, which also exhibited high water absorbency. Furthermore, neither method affected the structural nor mechanical properties of the oven-dried CMCNF foams. In particular, self-crosslinking by heat treatment proved to be as effective as using a crosslinking agent. Compared to the freeze-dried foam, the oven-dried foam exhibited slower methylene blue (MB) dye adsorption but a higher maximum adsorption capacity (238-250 mg/g), attributed to the closed pore structure and a larger specific surface area. In addition, the isotherm and reusability of the foam for MB adsorption were investigated. These crosslinking processes expanded the potential use of oven-dried CMCNF foams as adsorbents for cationic dyes.


Asunto(s)
Celulosa , Colorantes , Reactivos de Enlaces Cruzados , Azul de Metileno , Nanofibras , Agua , Nanofibras/química , Adsorción , Agua/química , Celulosa/química , Celulosa/análogos & derivados , Colorantes/química , Azul de Metileno/química , Reactivos de Enlaces Cruzados/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Epiclorhidrina/química
5.
Int J Mol Sci ; 25(8)2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38673952

RESUMEN

This study focuses on synthesizing and characterizing a graphene oxide/ZnTiO3/TiO2 (GO/ZTO/TO) composite to efficiently remove methylene blue (MB) from water, presenting a novel solution to address industrial dye pollution. GO and ZTO/TO were synthesized by the modified Hummers and sol-gel methods, respectively, while GO/ZTO/TO was prepared using a hydrothermal process. The structural and surface properties of the composite were characterized using various analytical techniques confirming the integration of the constituent materials and suitability for dye adsorption. The study revealed that GO/ZTO/TO exhibits an adsorption capacity of 78 mg g-1 for MB, with only a 15% reduction in adsorption efficiency until the fifth reuse cycle. Furthermore, the study suggests optimal adsorption near neutral pH and enhanced performance at elevated temperatures, indicating an endothermic reaction. The adsorption behavior fits the Langmuir isotherm, implying monolayer adsorption on homogeneous surfaces, and follows pseudo-second-order kinetics, highlighting chemical interactions at the surface as the rate-limiting step. The photocatalytic degradation of MB by GO/ZTO/TO follows pseudo-first-order kinetics, with a higher rate constant than that of GO alone, demonstrating the enhanced photocatalytic activity of the composite. In conclusion, GO/ZTO/TO emerges as a promising and sustainable approach for water purification, through an adsorption process and subsequent photocatalytic degradation.


Asunto(s)
Grafito , Azul de Metileno , Titanio , Contaminantes Químicos del Agua , Purificación del Agua , Azul de Metileno/química , Azul de Metileno/aislamiento & purificación , Titanio/química , Adsorción , Grafito/química , Catálisis , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Cinética , Procesos Fotoquímicos , Concentración de Iones de Hidrógeno , Zinc/química
6.
Sci Rep ; 14(1): 9279, 2024 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654039

RESUMEN

A simple and rapid electrochemical sensing method with high sensitivity and specificity of aptamers was developed for the detection of methylamphetamine (MAMP). A short anti-MAMP thiolated aptamer (Apt) with a methylene blue (MB) probe at 3'-end was immobilized on the surface of a gold electrode (MB-Apt-S/GE). The electrochemical signal appeared when MAMP presenting in the sample solution competed with cDNA for binding with MB-Apt-S. Under optimized conditions, the liner range of this signal-on electrochemical aptasensor for the detection of MAMP achieved from 1.0 to 10.0 nmol/L and 10.0-400 nmol/L. LOD 0.88 nmol/L were obtained. Satisfactory spiked recoveries of saliva and urine were also obtained. In this method, only 5 min were needed to incubate before the square wave voltammetry (SWV) analysis, which was much more rapid than other electrochemical sensors, leading to a bright and broad prospect for the detection of MAMP in biological sample. This method can be used for on-site rapid detection on special occasions, such as drug driving scenes, entertainment venues suspected of drug use, etc.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Técnicas Electroquímicas , Metanfetamina , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Aptámeros de Nucleótidos/química , Humanos , Metanfetamina/orina , Metanfetamina/análisis , ADN Complementario/genética , Saliva/química , Saliva/metabolismo , Electrodos , Límite de Detección , Oro/química , Azul de Metileno/química
7.
Biosens Bioelectron ; 256: 116273, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38621341

RESUMEN

Simple and reliable profiling of tumor-derived exosomes (TDEs) holds significant promise for the early detection of cancer. Nonetheless, this remains challenging owing to the substantial heterogeneity and low concentration of TDEs. Herein, we devised an accurate and highly sensitive electrochemical sensing strategy for TDEs via simultaneously targeting exosomal mucin 1 (MUC1) and programmed cell death ligand 1 (PD-L1). This approach employs high-affinity aptamers as specific recognition elements, utilizes rolling circle amplification and DNA nanospheres as effective bridges and signal amplifiers, and leverages methylene blue (MB) and doxorubicin (DOX) as robust signal reporters. The crux of this separation- and label-free method is the specific response of MB and DOX to G-quadruplex structures and DNA nanospheres, respectively. Quantifying TDEs using this strategy enabled precise discrimination of lung cancer patients (n = 25) from healthy donors (n = 12), showing 100% specificity (12/12), 92% sensitivity (23/25), and an overall accuracy of 94.6% (35/37), with an area under the receiver operating characteristic curve (AUC) of 0.97. Furthermore, the assay results strongly correlated with findings from computerized tomography and pathological analyses. Our approach could facilitate the early diagnosis of lung cancer through TDEs-based liquid biopsy.


Asunto(s)
Aptámeros de Nucleótidos , Antígeno B7-H1 , Técnicas Biosensibles , Doxorrubicina , Técnicas Electroquímicas , Exosomas , Neoplasias Pulmonares , Humanos , Técnicas Biosensibles/métodos , Exosomas/química , Técnicas Electroquímicas/métodos , Neoplasias Pulmonares/química , Aptámeros de Nucleótidos/química , Doxorrubicina/química , ADN/química , Azul de Metileno/química , Nanosferas/química , G-Cuádruplex
8.
J Environ Manage ; 357: 120738, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38574710

RESUMEN

The pyrolysis of mint stalks and lemon peels was performed to synthesize mint-stalks (MBC) and lemon-peels (LBC) derived biochars for adsorbing methylene blue (MB). The preparation, characterization, and application of MBC in adsorption have not been reported in the literature. MBC showed higher surface area and carbon content than that of LBC. The removal ratios of MB were 87.5% and 60% within 90 min for MBC and LBC, respectively at pH 7, temperature of 30oC, adsorbent dose of 0.5 g/L, and MB concentration of 5 mg/L. The optimal MBC dose was 1 g/L achieving a removal efficiency of 93.6% at pH 7, temperature of 30oC, contact time of 90 min, and initial dye concentration of 5.0 mg/L. The adsorption efficiency decreased from 98.6% to 31.33% by raising the dye concentration from 3.0 mg/L to 30 mg/L. Further, the increase of adsorbent dose to 10 g/L could achieve 94.2%, 90.3%, 87.6%, and 84.1% removal efficiencies of MB in the case of initial concentrations of 200 mg/L, 300 mg/L, 400 mg/L, and 500 mg/L, respectively. MBC showed high stability in adsorbing MB under five cycles, and the performed analyses after adsorption reaffirmed the stability of MBC. The adsorption mechanism indicated that the adsorption of MB molecules on the biochar's surface was mainly because of the electrostatic interaction, hydrogen bonding, and π-π stacking. Pseudo-second-order and Langmuir models could efficiently describe the adsorption of MB on the prepared biochar. The adsorption process is endothermic and spontaneous based on the adsorption thermodynamics. The proposed adsorption system is promising and can be implemented on a bigger scale. Moreover, the prepared biochar can be implemented in other applications such as photocatalysis, periodate, and persulfate activation-based advanced oxidation processes.


Asunto(s)
Azul de Metileno , Contaminantes Químicos del Agua , Azul de Metileno/química , Adsorción , Concentración de Iones de Hidrógeno , Carbón Orgánico/química , Termodinámica , Cinética
9.
ACS Sens ; 9(4): 2141-2148, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38578241

RESUMEN

The glycated hemoglobin (HbA1c) level, which is defined as the ratio of HbA1c to total hemoglobin (tHb, including glycated and unglycated hemoglobin), is considered one of the preferred indicators for diabetes monitoring. Generally, assessment of the HbA1c level requires separate determination of tHb and HbA1c concentrations after a complex separation step. This undoubtedly increases the cost of the assay, and the loss or degradation of HbA1c during the separation process results in a decrease in the accuracy of the assay. Therefore, this study explored a dual-signal acquisition method for the one-step simultaneous evaluation of tHb and HbA1c. Quantification of tHb: graphene adsorbed carbon quantum dots and methylene blue were utilized as the substrate material and linked to the antibody. tHb was captured on the substrate by the antibody. The unique heme group on tHb catalyzed the production of •OH from H2O2 to degrade methylene blue on the substrate, and a quantitative relationship between the tHb concentration and the methylene blue oxidation current signal was constructed. Quantification of HbA1c: complex labels with HbA1c recognition were made of ZIF-8-ferrocene-gold nanoparticles-mercaptophenylboronic acid. The specific recognition of the boronic acid bond with the unique cis-diol structure of HbA1c establishes a quantitative relationship between the oxidation current of the label-loaded ferrocene and the concentration of HbA1c. Thus, the HbA1c level can be assessed with only one signal readout. The sensor exhibited extensive detection ranges (0.200-600 ng/mL for tHb and 0.100-300 ng/mL for HbA1c) and low detection limits (4.00 × 10-3 ng/mL for tHb and 1.03 × 10-2 ng/mL for HbA1c).


Asunto(s)
Hemoglobina Glucada , Azul de Metileno , Hemoglobina Glucada/análisis , Humanos , Azul de Metileno/química , Grafito/química , Oro/química , Nanopartículas del Metal/química , Puntos Cuánticos/química , Hemoglobinas/análisis , Hemoglobinas/química , Ácidos Borónicos/química , Compuestos Ferrosos/química , Metalocenos/química , Límite de Detección , Técnicas Electroquímicas/métodos , Peróxido de Hidrógeno/química
10.
Molecules ; 29(8)2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38675629

RESUMEN

In this study, we prepared high-nitrogen self-doped porous carbons (NPC1 and NPC2) derived from the pruned branches and seeds of Zanthoxylum bungeanum using a simple one-step method. NPC1 and NPC2 exhibited elevated nitrogen contents of 3.56% and 4.22%, respectively, along with rich porous structures, high specific surface areas of 1492.9 and 1712.7 m2 g-1 and abundant surface groups. Notably, both NPC1 and NPC2 demonstrated remarkable adsorption abilities for the pollutant methylene blue (MB), with maximum monolayer adsorption capacities of 568.18 and 581.40 mg g-1, respectively. The adsorption kinetics followed the pseudo-second-order kinetics and the adsorption isotherms conformed to the Langmuir isotherm model. The adsorption mechanism primarily relied on the hierarchical pore structures of NPC1 and NPC2 and their diverse strong interactions with MB molecules. This study offers a new approach for the cost-effective design of nitrogen self-doped porous carbons, facilitating the efficient removal of MB from wastewater.


Asunto(s)
Carbono , Azul de Metileno , Nitrógeno , Zanthoxylum , Zanthoxylum/química , Adsorción , Nitrógeno/química , Azul de Metileno/química , Porosidad , Carbono/química , Cinética , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Aguas Residuales/química
11.
Chemosphere ; 357: 142116, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38663674

RESUMEN

This study explores the utilization of semiconductor-based photocatalysts for environmental remediation through photocatalytic degradation, harnessing solar energy for effective treatment. The primary focus is on the application of photocatalytic technology for the degradation of 2-chlorophenol and methylene blue, critical pollutants requiring remediation. The research involves the synthesis of binary AgAlO2/g-C3N4 nanocomposites through an exchange ion method, subsequent calcination, and sonication. This process enhances the transfer of photogenerated electrons from AgAlO2 to g-C3N4, resulting in a significantly increased reductive electron charge on the surface of g-C3N4. The photocatalytic activity of the synthesized composites is comprehensively examined in the degradation of 2-chlorophenol and methylene blue through detailed crystallographic, electron-microscopy, photoemission spectroscopy, electrochemical, and spectroscopic characterizations. Among the various composites, AgAlO2/20% g-C3N4 emerges as the most active photocatalyst, achieving an impressive 98% degradation of methylene blue and 97% degradation of 2-chlorophenol under visible light. Notably, AgAlO2/20% g-C3N4 surpasses bare AgAlO2 and bare g-C3N4, exhibiting 1.66 times greater methylene blue degradation and constant rate (k) values of 20.17 × 10-3 min-1, 4.18 × 10-3 min-1 and 3.48 × 10-3 min-1, respectively. The heightened photocatalytic activity is attributed to the diminished recombination rate of electron-hole pairs. Scavenging evaluations confirm that O2•- and h+ are the primary photoactive species steering methylene blue photodegradation over AgAlO2/g-C3N4 in the visible region. These findings present new possibilities for the development of efficient binary photocatalysts for environmental remediation.


Asunto(s)
Clorofenoles , Contaminantes Ambientales , Restauración y Remediación Ambiental , Luz , Azul de Metileno , Restauración y Remediación Ambiental/métodos , Clorofenoles/química , Catálisis , Contaminantes Ambientales/química , Azul de Metileno/química , Nanocompuestos/química , Fotólisis
13.
Sci Rep ; 14(1): 9877, 2024 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-38684756

RESUMEN

Our study focused on the optical behavior, methylene blue (MB) dye degradation potential, antibacterial performance, and silver and trioxide mineral interaction with different bacterial species. We found that the addition of silver nanoparticles (Ag NPs) to neodymium oxide (Nd2O3) resulted in a significant response, with an enlargement of the inhibition zone for bacterial species such as Staphylococcus aureus and Escherichia coli. Specifically, the inhibition zone for S. aureus increased from 9.3 ± 0.5 mm for pure Nd2O3 to 16.7 ± 0.4 mm for the Ag/Nd2O3 nano-composite, while for E. coli, it increased from 8.8 ± 0.4 mm for Nd2O3 to 15.9 ± 0.3 mm for Ag/Nd2O3. Furthermore, the optical behavior of the composites showed a clear band-gap narrowing with the addition of Ag NPs, resulting in enhanced electronic localization. The direct and indirect transitions reduced from 6.7 to 6.1 eV and from 5.2 to 2.9 eV, respectively. Overall, these results suggest that the Ag/Nd2O3 nano-composite has potential applications in sensor industries and water treatment, thanks to its enhanced optical behavior, antibacterial performance, and efficient MB degradation capabilities. In terms of MB degradation, the Ag/Nd2O3 mixed system exhibited more efficient degradation compared to pure Nd2O3. After 150 min, the MB concentration in the mixed system decreased to almost half of its starting point, while pure Nd2O3 only reached 33%.


Asunto(s)
Antibacterianos , Escherichia coli , Nanopartículas del Metal , Azul de Metileno , Neodimio , Óxidos , Plata , Staphylococcus aureus , Azul de Metileno/química , Nanopartículas del Metal/química , Plata/química , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Neodimio/química , Óxidos/química , Adsorción
14.
Biomaterials ; 308: 122561, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38603827

RESUMEN

Fungi infection is a serious threat to public health, but an effective antifungal strategy remains a challenge. Herein, a biomimetic nanocomposite with multifunctionalities, including fungi diagnosis, antifungal adhesion, precise fungi elimination, and cytokine sequestration, is constructed for battling Candida albicans (C. albicans) infection. By screening a range of cells, we find that the polarized macrophage cells have the strongest binding tendency toward C. albicans. Thus, their membranes were exfoliated to camouflage UCNPs and then decorated with photosensitizers (methylene blue, MB) and DNA sensing elements. The resulting nanocomposite can tightly bind to fungal surfaces, promote DNA recognition, and squeeze pro-inflammatory cytokines to relieve inflammation. Consequently, this nanocomposite can detect C. albicans with enhanced sensitivity and precisely eliminate fungal cells through photodynamic therapy with minimal phototoxicity because of its switchable fluorescence behavior. The developed nanocomposite with good biocompatibility achieves a satisfactory diagnostic and therapeutic effect in a C. albicans-infected mouse model, which offers a unique approach to fight fungi infection.


Asunto(s)
Antifúngicos , Materiales Biomiméticos , Candida albicans , Candidiasis , Nanocompuestos , Nanomedicina Teranóstica , Animales , Nanocompuestos/química , Ratones , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Candidiasis/tratamiento farmacológico , Candidiasis/diagnóstico , Nanomedicina Teranóstica/métodos , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Antifúngicos/química , Células RAW 264.7 , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Ratones Endogámicos BALB C , Biomimética/métodos , Humanos , Azul de Metileno/química
15.
Int J Biol Macromol ; 266(Pt 2): 131354, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38574933

RESUMEN

A floating adsorbent bead was prepared from polylactide (PLA) and maleic anhydride (MAH)-modified cellulose in a one-pot process (OP bead). Cellulose was extracted from waste lemongrass leaf (LGL) and modified with MAH in the presence of dimethylacetamide (DMAc). PLA was then added directly into the system to form sorbent beads by a phase separation process that reused unreacted MAH and DMAc as a pore former and a solvent, respectively. The chemical modification converted cellulose macrofibres (55.1 ± 31.5 µm) to microfibers (8.8 ± 1.5 µm) without the need for grinding. The OP beads exhibited more and larger surface pores and greater thermal stability than beads prepared conventionally. The OP beads also removed methylene blue (MB) more effectively, with a maximum adsorption capacity of 86.19 mg⋅g-1. The adsorption of MB on the OP bead fitted the pseudo-second order and the Langmuir isotherm models. The OP bead was reusable over five adsorption cycles, retaining 88 % of MB adsorption. In a mixed solution of MB and methyl orange (MO), the OP bead adsorbed 96 % of the cationic dye MB while repelling the anionic dye MO. The proposed method not only reduced time, energy and chemical consumption, but also enabled the fabrication of a green, effective and easy-to-use biosorbent.


Asunto(s)
Biomasa , Celulosa , Azul de Metileno , Poliésteres , Contaminantes Químicos del Agua , Purificación del Agua , Azul de Metileno/química , Azul de Metileno/aislamiento & purificación , Poliésteres/química , Celulosa/química , Adsorción , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Cinética , Agua/química
16.
Chemosphere ; 356: 141867, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38583535

RESUMEN

The rapid development of the industrial world causes wastewater containing dyes to continue to increase. Even in recent years, the food, textile, cosmetic, plastic, and printing industries have developed the use of dyes. Methylene blue (MB) is one of the cationic dyes widely used in dyeing silk, wood, and cotton because of its absorbency and good fastness to materials. The adsorption process is the best technique and preferred in removing dyes from wastewater due to excellent selectivity, high efficiency from high-quality treated effluent, flexibility in design, and simplicity. Therefore, there is a growing interest to identify low-cost alternative adsorbents that have reasonable adsorption efficiency, especially natural materials such as leaves. In this study, research on MB adsorption using leaves was analyzed using bibliometric analysis. Information of bibliometric is extracted from the Scopus database with the keyword "Methylene Blue", "Adsorption or Desorption", and "Leaves or leaf". The results showed that India, Desalination and Water Treatment, and SASTRA Deemed University were the country, journal, and institution that contributed the most publications on this topic. Therefore, it is expected that with the use of bibliometrics, the use of leaf-based MB adsorption processes in their potential for MB dye removal can be investigated especially for large-scale development.


Asunto(s)
Bibliometría , Colorantes , Azul de Metileno , Hojas de la Planta , Aguas Residuales , Azul de Metileno/química , Adsorción , Hojas de la Planta/química , Colorantes/química , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Eliminación de Residuos Líquidos/métodos , India
17.
Environ Geochem Health ; 46(3): 110, 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38460044

RESUMEN

The primary intent of the research is to comprehensively assess the environmental benefits and cost dynamics associated with the adsorption process of CS-RHA (Copper Slag and Rice Husk Ash) to produce a novel geopolymer adsorbent material for application in wastewater treatment. The geopolymer forms a polyiron sialate network under alkali activation by dissolving fayalite, and aluminium silicate to ferro-ferri silicate hydrate gel. The mechanical strength, leaching characteristics, and microstructure of the geopolymer were determined using XRD and FTIR, and magnetic properties by VSM as well surface properties were derived from BET surface area and zeta potential. Recognizing the critical role of sodium iron silicate hydrate (NFS) in the sorption of methylene blue (MB) dyestuff, batch experiments were carried out using different adsorbents. The results indicated that the dye removal efficiency increased from 60% in control samples (FS) to 98% for the blend (FS1) under different pH values. The data was found to fit with the nonlinear form of Freundlich isotherm and follow pseudo-second-order kinetics. The active adsorption sites were deduced as -O-Fe-O-Si-O-Na and Si-OH groups. The addition of RHA increases the adsorption capacity of the geopolymer in a short time through chemical adsorption. The significant negative surface charge promotes MB adsorption via improved electrostatic attraction. The spent adsorbents were recovered through magnetic separation with a retrieval rate of 80-85% and active sites were rejuvenated by calcination. Consequently, waste copper slag emerges as a promising adsorbent with minimum potential ecological risk and high effective recycling capacity.


Asunto(s)
Cobre , Contaminantes Químicos del Agua , Biomasa , Ácido Silícico , Reciclaje , Adsorción , Azul de Metileno/química , Cinética , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/química
18.
Environ Sci Pollut Res Int ; 31(16): 24113-24128, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38436853

RESUMEN

The presence of organic dyes in aquatic systems poses a significant threat to ecosystems and human well-being. Due to recycling challenges, traditional commercial activated carbon is not cost-effective. To address this, an imidazolate acid zeolite framework-8 (ZIF-8)-modified magnetic adsorbent (ZMPLB-800) was synthesized through the in-situ formation of ZIF-8 and subsequent carbonization at 800 °C, using magnetic pineapple leaf biochar (MPLB) as a carrier. The porous structure of ZMPLB-800 facilitates the rapid passage of dye molecules, enhancing adsorption performance. ZMPLB-800 exhibited remarkable adsorption capacity for methylene blue (MB) across a pH range of 3-13, with a maximum adsorption capacity of 455.98 mg g-1. Adsorption kinetics and thermodynamics followed the pseudo-second-order kinetic model and Langmuir isotherm model. Mechanisms of MB adsorption included pore filling, hydrogen bonding, electrostatic interactions, π-π interactions, and complexation through surface functional groups. Additionally, ZMPLB-800 demonstrated excellent regeneration performance, recording a removal efficiency exceeding 87% even after five adsorption/desorption cycles. This study provides a novel strategy for treating dye wastewater with MOF composites, laying the foundation for waste biomass utilization.


Asunto(s)
Ananas , Contaminantes Químicos del Agua , Zeolitas , Adsorción , Carbón Orgánico/química , Ecosistema , Concentración de Iones de Hidrógeno , Cinética , Fenómenos Magnéticos , Azul de Metileno/química , Hojas de la Planta , Aguas Residuales , Contaminantes Químicos del Agua/química
19.
Environ Pollut ; 348: 123745, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38499169

RESUMEN

The article discusses the removal of methylene blue (MB) dye, a common cationic dye used in the textile industry, from aqueous solutions through an adsorption process. The use of porous components as adsorbents are shown to facilitate complete separation after the process is completed. The substrate was synthesized by connecting zinc copper ferrite (ZnCuFe2O4), polyethyleneimine (PEI), and Graphene Oxide (GO) sheets to MCM-48, which is a mesoporous material. The surface of MCM-48 was modified using CPTMS, which created an O-Si-Cl bridge, thereby improving the adsorption rate. The substrate was shown to have suitable sites for electrostatic interactions and creating hydrogen bonds with MB. The adsorption process from the Freundlich isotherm (R2 = 0.9224) and the pseudo-second-order diagram (R2 = 0.9927) demonstrates the adsorption of several layers of dye on the heterogeneous surface of the substrate. The synthesized substrate was also shown to have good bactericidal activity against E. coli and S. aureus bacterial strain. Furthermore, the substrate maintained its initial ability to adsorb MB dye for four consecutive cycles. The research resulted that ZnCuFe2O4@MCM-48/PEI-GO substrate has the potential for efficient and economical removal of MB dye from aqueous solutions (R = 88.82%) (qmax = 294.1176 mg. g-1), making it a promising solution for the disposal of harmful industrial waste.


Asunto(s)
Compuestos Férricos , Grafito , Nanopartículas , Contaminantes Químicos del Agua , Purificación del Agua , Dióxido de Silicio , Polietileneimina , Cobre , Zinc , Escherichia coli , Porosidad , Staphylococcus aureus , Antibacterianos/farmacología , Azul de Metileno/química , Purificación del Agua/métodos , Adsorción , Cinética , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno
20.
Int J Mol Sci ; 25(6)2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38542365

RESUMEN

Photodynamic therapy (PDT) is a therapeutic option for cancer, in which photosensitizer (PS) drugs, light, and molecular oxygen generate reactive oxygen species (ROS) and induce cell death. First- and second-generation PSs presented with problems that hindered their efficacy, including low solubility. Thus, second-generation PSs loaded into nanocarriers were produced to enhance their cellular uptake and therapeutic efficacy. Among other compounds investigated, the dye methylene blue (MB) showed potential as a PS, and its photodynamic activity in tumor cells was reported even in its nanocarrier-delivered form, including liposomes. Here, we prepared polydopamine (PDA)-coated liposomes and efficiently adsorbed MB onto their surface. lipoPDA@MB vesicles were first physico-chemically characterized and studies on their light stability and on the in vitro release of MB were performed. Photodynamic effects were then assessed on a panel of 2D- and 3D-cultured cancer cell lines, comparing the results with those obtained using free MB. lipoPDA@MB uptake, type of cell death induced, and ability to generate ROS were also investigated. Our results show that lipoPDA@MB possesses higher photodynamic potency compared to MB in both 2D and 3D cell models, probably thanks to its higher uptake, ROS production, and apoptotic cell death induction. Therefore, lipoPDA@MB appears as an efficient drug delivery system for MB-based PDT.


Asunto(s)
Indoles , Fotoquimioterapia , Polímeros , Fotoquimioterapia/métodos , Liposomas , Azul de Metileno/farmacología , Azul de Metileno/química , Especies Reactivas de Oxígeno , Fármacos Fotosensibilizantes/química , Línea Celular Tumoral
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