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

RESUMO

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


Assuntos
Cobalto , Eletroquímica , Eletrodos , Nanocompostos , Níquel , Nanocompostos/química , Níquel/química , Cobalto/química , Difração de Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Luminescência , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Fenômenos Magnéticos , Nanopartículas/química , Luz , Catálise , Óxidos/química , Azul de Metileno/metabolismo
2.
Luminescence ; 39(5): e4758, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38712530

RESUMO

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.


Assuntos
Compostos Férricos , Azul de Metileno , Compostos de Nitrogênio , Energia Solar , Poluentes Químicos da Água , Zinco , Catálise , Poluentes Químicos da Água/química , Compostos Férricos/química , Azul de Metileno/química , Zinco/química , Magnésio/química , Fotólise , Processos Fotoquímicos , Corantes/química , Nanocompostos/química , Grafite/química , Águas Residuárias/química , Nitrilas/química
3.
J Appl Oral Sci ; 32: e20230447, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38695448

RESUMO

OBJECTIVE: To evaluate whether antimicrobial photodynamic therapy (aPDT) repairs bisphosphonate-related osteonecrosis of the jaw (BRONJ) modulated by the reduction of NF-kB protein in a murine model. METHODOLOGY: Male Wistar rats (N=30) were divided into the following groups (n=6/group): negative control (NC); experimental osteonecrosis (ONE); ONE + photosensitizer (PS); ONE + photobiomodulation (PBM); and ONE + aPDT. Over 8 weeks, ONE was induced by zoledronic acid 250 µg/kg injections, except in the NC group, which received sterile 0.9% saline, followed by extraction of the lower left first molar. Red light laser irradiation (wavelength ~660 nm, power 50 mW, energy of 2 J, energy dose of 66.67 J/cm2 for 40 s) was performed once a week for 4 weeks. Methylene blue 0.3% was used as PS. The animals were euthanized and examined macroscopically for the presence of exposed bone and epithelial repair and microscopically by histochemical (hematoxylin-eosin and Masson's trichrome staining) and immunohistochemical (anti-NF-kB) methods. Macroscopic and histomorphometric data were analyzed by one-way ANOVA and Tukey's post-test (p<0.05). RESULTS: Mucosal repair, viable osteocytes, and NF-kB immunostaining were observed in the NC, ONE+PS, ONE+PBM, and ONE+aPDT groups. The ONE group showed no mucosal repair, showing empty lacunae and multifocal immunostaining for NF-kB. The ONE+PBM and ONE+aPDT groups had greater deposition of extracellular matrix and less necrotic bone tissue (p<0.05). CONCLUSION: PBM and aPDT treatments for BRONJ were effective for bone and epithelial repair, in addition to reducing inflammation mediated by the decrease of NF-kB protein in the irradiated regions.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Modelos Animais de Doenças , Imuno-Histoquímica , NF-kappa B , Fotoquimioterapia , Fármacos Fotossensibilizantes , Ratos Wistar , Animais , Masculino , Fotoquimioterapia/métodos , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/patologia , NF-kappa B/análise , Fármacos Fotossensibilizantes/farmacologia , Fatores de Tempo , Reprodutibilidade dos Testes , Ácido Zoledrônico/farmacologia , Resultado do Tratamento , Imidazóis/farmacologia , Difosfonatos/farmacologia , Terapia com Luz de Baixa Intensidade/métodos , Azul de Metileno/farmacologia , Azul de Metileno/uso terapêutico , Análise de Variância , Distribuição Aleatória , Conservadores da Densidade Óssea/farmacologia
4.
J Med Life ; 17(1): 28-34, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38737667

RESUMO

This study assessed the efficacy of antimicrobial photodynamic therapy (PDT) using a 650 nm diode laser combined with methylene blue (MB) as a photosensitizer to inhibit the growth of Candida albicans (C. albicans). Oral samples were collected from 75 patients diagnosed with oral thrush. C. albicans was isolated and identified using traditional methods and the VITEK 2 YST system. Samples (n = 25) were divided into five groups: Group 1 (control, n = 5) consisted of C. albicans suspensions in saline; Group 2 (n = 5) treated with nystatin; Group 3 (n = 5) exposed to a 650 nm diode laser in continuous mode at 200 mW for 300 seconds; Group 4 (n = 5) treated with 650 nm laser and MB as a photosensitizer; Group 5 (n = 5) exposed to the laser in combination with nystatin. Statistical analysis using ANOVA, Dunnett's t-test (P = 0.05), and LSD (P = 0.001) revealed significant differences in C. albicans counts pre- and post-treatment. Group 5 showed the most significant reduction in C. albicans, followed by Group 4, while Groups 2 and 3 showed the least variation. The findings suggest that PDT using a 650 nm diode laser with methylene blue (in continuous mode at 200 mW for 300 seconds) effectively reduced the prevalence of C. albicans.


Assuntos
Candida albicans , Azul de Metileno , Fotoquimioterapia , Fármacos Fotossensibilizantes , Candida albicans/efeitos dos fármacos , Fotoquimioterapia/métodos , Humanos , Azul de Metileno/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Lasers Semicondutores/uso terapêutico , Candidíase Bucal/tratamento farmacológico , Candidíase Bucal/microbiologia , Nistatina/farmacologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico
5.
Bioresour Technol ; 401: 130712, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38641300

RESUMO

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.


Assuntos
Carvão Vegetal , Lignina , Lignina/química , Adsorção , Carvão Vegetal/química , Cinética , Azul de Metileno/química , Vermelho Congo/química
6.
Chemosphere ; 357: 141982, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38608778

RESUMO

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.


Assuntos
Carvão Vegetal , Corantes , Azul de Metileno , Impressão Tridimensional , Poluentes Químicos da Água , Purificação da Água , Carvão Vegetal/química , Adsorção , Corantes/química , Poluentes Químicos da Água/química , Azul de Metileno/química , Purificação da Água/métodos , Pós , Cinética , Cátions/química , Filtração/métodos , Porosidade , Carbono/química , Concentração de Íons de Hidrogênio
7.
Int J Biol Macromol ; 267(Pt 1): 131432, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583849

RESUMO

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.


Assuntos
Celulose , Corantes , Reagentes de Ligações Cruzadas , Azul de Metileno , Nanofibras , Água , Nanofibras/química , Adsorção , Água/química , Celulose/química , Celulose/análogos & derivados , Corantes/química , Azul de Metileno/química , Reagentes de Ligações Cruzadas/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Epicloroidrina/química
8.
Int J Mol Sci ; 25(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38673952

RESUMO

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.


Assuntos
Grafite , Azul de Metileno , Titânio , Poluentes Químicos da Água , Purificação da Água , Azul de Metileno/química , Azul de Metileno/isolamento & purificação , Titânio/química , Adsorção , Grafite/química , Catálise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Cinética , Processos Fotoquímicos , Concentração de Íons de Hidrogênio , Zinco/química
9.
Med Sci Monit ; 30: e941102, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38650310

RESUMO

BACKGROUND This retrospective study of 42 patients with popliteal cysts (or Baker cysts) aimed to compare the effects on duration and outcomes of arthroscopic surgical debridement with and without the use of cyst injection with methylene blue (MB). MATERIAL AND METHODS Medical records of patients who underwent conventional arthroscopic surgery (n=20) or arthroscopic surgery after MB injection (n=22) for popliteal cysts between 2018 and 2021 were reviewed. The MB group underwent arthroscopic popliteal cystectomy with MB as the marker, and the control group underwent conventional arthroscopic popliteal cystectomy. Surgical time of cyst resection, postoperative bruising extent, complication rate, and cyst recurrence rate of the 2 groups were compared. RESULTS The MB group had a faster surgical cyst removal time (16.5±1.5 min) than the control group (24.5±1.6 min; P<0.05). The MB group had less postoperative bruising (1 case, 4.5%) than the control group (5 cases, 25%; P<0.05). The surgical results were similar in both groups, with a Lysholm score of 87.23±1.80 in the MB group and 87.23±1.62 (P>0.05) in the control group. CONCLUSIONS This study showed that preoperative injection of MB for popliteal cysts before arthroscopic debridement improved cyst localization and ease and accuracy of surgery and reduced operative time, adjacent tissue damage, postoperative complications, and recurrence rate.


Assuntos
Artroscopia , Desbridamento , Azul de Metileno , Cisto Popliteal , Humanos , Artroscopia/métodos , Cisto Popliteal/cirurgia , Masculino , Desbridamento/métodos , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto , Complicações Pós-Operatórias/etiologia , Idoso
10.
Int J Mol Sci ; 25(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38612599

RESUMO

Methemoglobinemia is a potentially life-threatening, rare condition in which the oxygen-carrying capacity of hemoglobin is diminished. We present the case of a 3-year-old boy treated for T-cell acute lymphoblastic leukemia (T-ALL) who developed methemoglobinemia (MetHb 57.1%) as a side effect of ifosfamide administration. Due to his critical condition, the patient was transferred to the intensive care unit (ICU). The therapy included methylene blue administration, an exchange transfusion, catecholamine infusion, and steroids. Improving the general condition allowed for continuing chemotherapy without ifosfamide and completion of the HR2 block. Vigilance for methemoglobinemia as a very rare side effect should be widespread when using ifosfamide in the treatment protocols.


Assuntos
Metemoglobinemia , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Masculino , Humanos , Pré-Escolar , Metemoglobinemia/induzido quimicamente , Ifosfamida/efeitos adversos , Azul de Metileno/efeitos adversos , Catecolaminas
11.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612671

RESUMO

This paper offers a thorough investigation of hyperparameter tuning for neural network architectures using datasets encompassing various combinations of Methylene Blue (MB) Reduction by Ascorbic Acid (AA) reactions with different solvents and concentrations. The aim is to predict coefficients of decay plots for MB absorbance, shedding light on the complex dynamics of chemical reactions. Our findings reveal that the optimal model, determined through our investigation, consists of five hidden layers, each with sixteen neurons and employing the Swish activation function. This model yields an NMSE of 0.05, 0.03, and 0.04 for predicting the coefficients A, B, and C, respectively, in the exponential decay equation A + B · e-x/C. These findings contribute to the realm of drug design based on machine learning, providing valuable insights into optimizing chemical reaction predictions.


Assuntos
Ácido Ascórbico , Azul de Metileno , Desenho de Fármacos , Aprendizado de Máquina , Redes Neurais de Computação
12.
Sci Rep ; 14(1): 9279, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654039

RESUMO

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.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Técnicas Eletroquímicas , Metanfetamina , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Aptâmeros de Nucleotídeos/química , Humanos , Metanfetamina/urina , Metanfetamina/análise , DNA Complementar/genética , Saliva/química , Saliva/metabolismo , Eletrodos , Limite de Detecção , Ouro/química , Azul de Metileno/química
13.
Biosens Bioelectron ; 256: 116273, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621341

RESUMO

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.


Assuntos
Aptâmeros de Nucleotídeos , Antígeno B7-H1 , Técnicas Biossensoriais , Doxorrubicina , Técnicas Eletroquímicas , Exossomos , Neoplasias Pulmonares , Humanos , Técnicas Biossensoriais/métodos , Exossomos/química , Técnicas Eletroquímicas/métodos , Neoplasias Pulmonares/química , Aptâmeros de Nucleotídeos/química , Doxorrubicina/química , DNA/química , Azul de Metileno/química , Nanosferas/química , Quadruplex G
14.
Chemosphere ; 355: 141879, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38570050

RESUMO

The use of emerging composite materials has been booming to remove environmental pollutants. The aim of this research is to develop a new composite based on Cs3Bi2Cl9 perovskite and graphitic carbon nitride (g-C3N4) to investigate the photocatalytic performance under visible light irradiation. To achieve this, we produce the Cs3Bi2Cl9/g-C3N4 heterojunctions through a simple self-assembly synthesis. The as-synthesized composites are characterized using XRD, FTIR, FESEM, TEM, BET and EDX techniques. The photocatalytic performance of Cs3Bi2Cl9/g-C3N4 is examined in the degradation of various water contaminants, including 4-nitrophenol (4-NP), tetracycline antibiotic (TC), methylene blue (MB) and methyl orange (MO). The experimental results indicate the superior photocatalytic performance of the composites in the degradation of pollutants compared to pure Cs3Bi2Cl9 and g-C3N4. The 10% Cs3Bi2Cl9/g-C3N4 composite achieves the optimal degradation efficiency of 100, 92, 98.7, and 85.1% of 4-NP, TC, MB, and MO, respectively. This superior photocatalytic activity attributes to improved optical and electrochemical properties, including enhanced absorption ability, narrowing band gap, promoted separation efficiency of photogenerated carriers, and a high redox potential, which is confirmed by UV-vis DRS, PL, EIS, and CV analyses. The 10% Cs3Bi2Cl9/g-C3N4 composite also demonstrates high photocatalytic stability after four consecutive cycles. Radical trapping tests show that superoxide radicals (•O2-), holes (h+), and hydroxyl radicals (•OH) contribute to the photocatalytic process. Based on the obtained data, a direct Z-scheme heterojunction mechanism is proposed. Overall, this research offers a new stable photocatalyst with excellent prospect for photocatalytic applications.


Assuntos
Compostos Azo , Poluentes Ambientais , Água , Cinética , Física , Azul de Metileno
15.
J Environ Manage ; 357: 120738, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38574710

RESUMO

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.


Assuntos
Azul de Metileno , Poluentes Químicos da Água , Azul de Metileno/química , Adsorção , Concentração de Íons de Hidrogênio , Carvão Vegetal/química , Termodinâmica , Cinética
16.
J Environ Manage ; 357: 120786, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38583386

RESUMO

An innovative task was undertaken to convert ubiquitous and toxic electronic waste, waste toner powder (WTP), into novel adsorbents. Alkaline modification with KOH, NaOH, and NH4OH was employed for the first time to synthesize a series of surface-modified WTP with enhanced dispersibility and adsorption capacity. XRD, XRF, FTIR, and BET analyses confirmed that the prepared KOH-WTP, NaOH-WTP, and NH4OH-WTP were oxygen-functionalized self-doped iron oxide-graphite nanocomposites. The prepared adsorbents were used to remove methylene blue and tetracycline from aqueous solutions. KOH-WTP (0.1 g/100 mL) adsorbed 80% of 10 mg/L methylene blue within 1 h, while 0.1 g/100 mL NH4OH-WTP removed 72% of 10 mg/L tetracycline in 3 h. Exploring surface chemistry by altering solution pH and temperature suggested that hydrogen bonding, electrostatic interactions, π-π electron stacking, and pore filling were plausible adsorption mechanisms. Scanning electron microscopy revealed a diminishing adsorbents porosity after adsorption proving the filling of pores by the adsorbates. KOH-WTP and NH4OH-WTP removed 77% and 61% of methylene blue and tetracycline respectively in the fourth reuse. The adsorption data of methylene blue and tetracycline fitted the Freundlich isotherm model. The maximum adsorption capacities of KOH-WTP and NH4OH-WTP for methylene blue and tetracycline were 59 mg/g and 43 mg/g respectively. The prepared adsorbents were also compared with other adsorbents to assess their performance. The transformation of waste toner powder into magnetically separable oxygen-functionalized WTP with outstanding recyclability and adsorption capacity showcases a significant advancement in sustainable wastewater treatment. This further aligns with the principles of the circular economy through the utilization of toxic e-waste in value-added applications. Additionally, magnetic separation of surface-modified WTP post-treatment can curtail filtration and centrifugation expenses and adsorbent loss during wastewater treatment.


Assuntos
Compostos Férricos , Grafite , Nanocompostos , Poluentes Químicos da Água , Azul de Metileno , Adsorção , Pós , Hidróxido de Sódio , Tetraciclina , Antibacterianos , Oxigênio , Poluentes Químicos da Água/análise , Cinética , Concentração de Íons de Hidrogênio
17.
Braz J Cardiovasc Surg ; 39(3): e20230066, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38569061

RESUMO

Microvasculature failure is expected in sepsis and at higher amine concentrations. Therefore, special attention focused individually on microcirculation is needed. Here, we present that methylene blue can prevent leukocytes from adhering to the endothelium in a rat model of lipopolysaccharide-induced endotoxemia. As hypothesis evidence, an intravital microscopy image is presented.


Assuntos
Sepse , Vasoplegia , Ratos , Animais , Azul de Metileno/farmacologia , Azul de Metileno/uso terapêutico , Vasoconstritores , Vasoplegia/tratamento farmacológico , Sepse/tratamento farmacológico , Microscopia Intravital
18.
ACS Sens ; 9(4): 2141-2148, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38578241

RESUMO

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).


Assuntos
Hemoglobinas Glicadas , Azul de Metileno , Hemoglobinas Glicadas/análise , Humanos , Azul de Metileno/química , Grafite/química , Ouro/química , Nanopartículas Metálicas/química , Pontos Quânticos/química , Hemoglobinas/análise , Hemoglobinas/química , Ácidos Borônicos/química , Compostos Ferrosos/química , Metalocenos/química , Limite de Detecção , Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio/química
19.
Molecules ; 29(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38675629

RESUMO

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.


Assuntos
Carbono , Azul de Metileno , Nitrogênio , Zanthoxylum , Zanthoxylum/química , Adsorção , Nitrogênio/química , Azul de Metileno/química , Porosidade , Carbono/química , Cinética , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Águas Residuárias/química
20.
BMC Surg ; 24(1): 108, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615003

RESUMO

BACKGROUND: Postoperative hypoparathyroidism caused by parathyroid injury is a problem faced by thyroid surgeons. The current technologies for parathyroid imaging all have some defects. METHODS: Patients with differentiated thyroid carcinoma (DTC) who underwent unilateral thyroidectomy plus ipsilateral central lymph node dissection were recruited. We dissected the main trunk of the superior thyroid artery entering the thyroid gland and placed the venous indwelling tube into the artery. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were calculated. RESULTS: A total of 132 patients enrolled in this single-arm clinical trial, 105 of them completed retrograde catheterization via the superior artery. The sensitivity was 69.23 and 83.33% respectively. The specificity was 72.91 and 64.89%. The accuracy was 72.91 and 64.89%. The PPV was 85.71 and 81.08%. The NPV was 22.58 and 45.45%. There were no patients with allergic reactions to the methylene blue, or methylene blue toxicity. CONCLUSIONS: Retrograde injection of methylene blue via the superior thyroid artery is an effective and safe method to visualize parathyroid glands. This method can accurately locate the target organ by ultraselecting the blood vessel and injecting the contrast agent while avoiding background contamination and reducing the amount of contrast agent. TRIAL REGISTRATION: Clinical trial registration numbers and date of registration: ChiCTR2300077263、02/11/2023.


Assuntos
Glândulas Paratireoides , Glândula Tireoide , Humanos , Artérias , Meios de Contraste , Azul de Metileno , Glândulas Paratireoides/diagnóstico por imagem , Glândulas Paratireoides/cirurgia , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/cirurgia
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