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Chemosphere Oct 2023Dyestuff wastewater and pharmaceutical wastewater have become typical representatives of water pollution. In this study, a novel nano-silica-biochar composite (NSBC) was...
Dyestuff wastewater and pharmaceutical wastewater have become typical representatives of water pollution. In this study, a novel nano-silica-biochar composite (NSBC) was synthesized based on corn straw as raw material, by a combination of ball milling, pyrolysis and KOH activation. The modified biochar with rough surface had higher specific surface area (117.67-132.82 m/g), developed pore structure (0.12-0.15 cm/g) and abundant surface functional groups (-OH, -COOH, Si-O and aromatic CC were dominated). These provided abundant active sites for the adsorption of pollutants. The adsorption capacities of NSBC for Methylene Blue (MB) and Tetracycline (TC) were both higher than that of other similar products, the maximum adsorption capacity of Langmuir were 247.22 and 86.95 mg/g, respectively. After five adsorption-desorption cycle experiments, the adsorption capacities of NSBC for both were still excellent, reaching 99.30 and 19.87 mg/g, respectively. Due to the different structure and molecular size of MB and TC, the adsorption capacities of NSBC were significantly different, especially the influence of solution pH value. The adsorption mechanisms were comprehensively discussed by FTIR and XPS of the samples before and after adsorption, and combining experimental results of BET and simultaneously, which were manifested as monolayer chemisorption, specifically surface complexation, hydrogen bonding, n-π/π-π conjugation, electrostatic interaction and pore filling.
Topics: Methylene Blue; Silicon Dioxide; Wastewater; Adsorption; Charcoal; Anti-Bacterial Agents; Tetracycline; Water Pollutants, Chemical; Kinetics
PubMed: 37399993
DOI: 10.1016/j.chemosphere.2023.139395 -
Methylene blue as adjunctive therapy in septic shock: correct drug diluent derives optimal efficacy.Critical Care (London, England) Aug 2023
Topics: Humans; Methylene Blue; Shock, Septic; Dental Care; Patients
PubMed: 37644588
DOI: 10.1186/s13054-023-04615-2 -
Biotechnic & Histochemistry : Official... Nov 2024Romanowsky staining was an important methodological breakthrough in diagnostic hematology and cytopathology during the late 19 and early 20 centuries; it has facilitated... (Review)
Review
Romanowsky staining was an important methodological breakthrough in diagnostic hematology and cytopathology during the late 19 and early 20 centuries; it has facilitated for decades the work of biologists, hematologists and pathologists working with blood cells. Despite more than a century of studying Romanowsky staining, no systematic review has been published that explains the chemical processes that produce the "Romanowsky effect" or "Romanowsky-Giemsa effect" (RGE), i.e., a purple coloration arising from the interaction of an azure dye with eosin and not due merely to their simultaneous presence. Our review is an attempt to build a bridge between chemists and biomedical scientists and to summarize the available data on methylene blue (MB) demethylation as well as the related reduction and decomposition of MB to simpler compounds by both light and enzyme systems and microorganisms. To do this, we analyze modern data on the mechanisms of MB demethylation both in the presence of acids and bases and by disproportionation due to the action of light. We also offer an explanation for why the RGE occurs only when azure B, or to a lesser extent, azure A is present by applying experimental and calculated physicochemical parameters including dye-DNA binding constants and electron density distributions in the molecules of these ligands. Finally, we discuss modern techniques for obtaining new varieties of Romanowsky dyes by modifying previously known ones. We hope that our critical literature study will help scientists understand better the chemical and physicochemical processes and mechanisms of cell staining with such dyes.
Topics: Azure Stains; Staining and Labeling; Coloring Agents; Methylene Blue; Eosine Yellowish-(YS)
PubMed: 37929609
DOI: 10.1080/10520295.2023.2273860 -
Sensors (Basel, Switzerland) Nov 2023This paper describes the development of a simple voltammetric biosensor for the stereoselective discrimination of myo-inositol (myo-Ins) and D-chiro-inositol...
This paper describes the development of a simple voltammetric biosensor for the stereoselective discrimination of myo-inositol (myo-Ins) and D-chiro-inositol (D-chiro-Ins) by means of bovine serum albumin (BSA) adsorption onto a multi-walled carbon nanotube (MWCNT) graphite screen-printed electrode (MWCNT-GSPE), previously functionalized by the electropolymerization of methylene blue (MB). After a morphological characterization, the enantioselective biosensor platform was electrochemically characterized after each modification step by differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). The results show that the binding affinity between myo-Ins and BSA was higher than that between D-chiro-Ins and BSA, confirming the different interactions exhibited by the novel BSA/MB/MWCNT/GSPE platform towards the two diastereoisomers. The biosensor showed a linear response towards both stereoisomers in the range of 2-100 μM, with LODs of 0.5 and 1 μM for myo-Ins and D-chiro-Ins, respectively. Moreover, a stereoselectivity coefficient α of 1.6 was found, with association constants of 0.90 and 0.79, for the two stereoisomers, respectively. Lastly, the proposed biosensor allowed for the determination of the stereoisomeric composition of myo-/D-chiro-Ins mixtures in commercial pharmaceutical preparations, and thus, it is expected to be successfully applied in the chiral analysis of pharmaceuticals and illicit drugs of forensic interest.
Topics: Inositol; Methylene Blue; Stereoisomerism
PubMed: 38005597
DOI: 10.3390/s23229211 -
The American Journal of Nursing Apr 2024
Topics: Humans; Promethazine
PubMed: 38511703
DOI: 10.1097/01.NAJ.0001010556.28403.79 -
Bioresource Technology Jul 2023Hydrochars are promising sorbents for wastewater treatment. Herein, two acrylate-modified hydrochars (AMHC and AMHC) were obtained by grafting acrylic acid on the...
Hydrochars are promising sorbents for wastewater treatment. Herein, two acrylate-modified hydrochars (AMHC and AMHC) were obtained by grafting acrylic acid on the surface of two hydrochars (MHC and MHC hydrothermally carbonized in water and acidic medium respectively) with free radical polymerization. Characterizations show that MHC is more prone to free radical polymerization than MHC does, and has higher carboxylate content after modification. The adsorption amounts of AMHC over methylene blue (MB) and Pb(II) are much higher than those of AMHC. Pseudo-second-order kinetic and Langmuir isotherm equations well fit the Pb(II) and MB sorption data of AMHC. The Pb(II) adsorptive mechanism is mainly inner-surface complexation accompanied by ion exchange and cation-π interaction. MB adsorption involves ion exchange, electrostatic interaction, H-bonding and π-π interaction. Hence, the one-step modification method of free radical polymerization under alkaline condition has great potential for preparing carboxylate-modified hydrochars to adsorb cationic pollutants.
Topics: Methylene Blue; Lead; Adsorption; Water Pollutants, Chemical; Acrylates; Water; Kinetics; Carboxylic Acids; Hydrogen-Ion Concentration
PubMed: 37080438
DOI: 10.1016/j.biortech.2023.129067 -
Diseases of Aquatic Organisms Sep 2023The emerging fungal pathogen Batrachochytrium dendrobatidis (Bd) threatens hundreds of amphibian species globally. During laboratory-based experiments it is often...
The emerging fungal pathogen Batrachochytrium dendrobatidis (Bd) threatens hundreds of amphibian species globally. During laboratory-based experiments it is often essential to quantify live Bd cells, but a comparison of the effectiveness of methods for counting and assessing the viability of the infectious zoospore life stage has not been done. A direct comparison of staining methods that assess viability will ensure that the most accurate and efficient method is used. Here, we compared the use of 2 relatively cheap common stains, trypan blue and methylene blue, and assessed their accuracy and precision for estimating the viability of Bd zoospores during both manual counting and colorimetric assays. We stained known proportions of killed Bd zoospores (0, 0.25, 0.50, 0.75, and 1.00) with each stain and estimated the proportion of stained (dead) and unstained (viable) cells in each sample using both manual counting and colorimetric assays. Trypan blue was found to be a much more effective stain than methylene blue for both microscopy and colorimetric assays. Additionally, counting zoospores via microscopy was both a more accurate and precise technique. We recommend using manual counts via microscopy using the trypan blue stain for assessing Bd zoospore viability.
Topics: Animals; Batrachochytrium; Methylene Blue; Trypan Blue; Biological Assay
PubMed: 37706644
DOI: 10.3354/dao03749 -
Cutis Dec 2023Toluidine blue (TB) is a metachromatic dye used as a stain in frozen sections in Mohs micrographic surgery (MMS). The current literature on the use of TB is sparse and... (Review)
Review
Toluidine blue (TB) is a metachromatic dye used as a stain in frozen sections in Mohs micrographic surgery (MMS). The current literature on the use of TB is sparse and generally qualitative in nature. The aim of this systematic review was to summarize and evaluate the existing literature analyzing TB use in MMS. The PubMed and Cochrane databases were searched for relevant studies published before December 1, 2019. Studies that analyzed the use of TB in frozen sections applicable to MMS were included. A total of 25 articles were reviewed, of which 12 fit the inclusion criteria. Our analysis showed that TB may play an important role in the successful diagnosis and treatment of particular cutaneous tumors.
Topics: Humans; Mohs Surgery; Tolonium Chloride; Skin Neoplasms; Coloring Agents; Neoplasm Recurrence, Local
PubMed: 38290073
DOI: 10.12788/cutis.0915 -
Environmental Research Aug 2023In this study, the deployment of post Reverse Osmosis (RO)-carbon as a adsorbent for dye removal from water has been investigated. The post RO-carbon was thermally...
In this study, the deployment of post Reverse Osmosis (RO)-carbon as a adsorbent for dye removal from water has been investigated. The post RO-carbon was thermally activated (RO900), and the material thus obtained exhibited high surface area viz. 753 m/g. In the batch system, the efficient Methylene Blue (MB) and Methyl Orange (MO) removal was obtained by using 0.08 g and 0.13 g/50 mL adsorbent dosage respectively. Moreover, 420 min was the optimized equilibration time for both the dyes. The maximum adsorption capacities of RO900 for MB and MO dyes were 223.29 and 158.14 mg/g, respectively. The comparatively higher MB adsorption was attributed to the electrostatic attraction between adsorbent and MB. The thermodynamic findings revealed the process as spontaneous, endothermic, and accompanied by entropy increment. Additionally, simulated effluent was treated, and >99% dye removal efficiency was achieved. To mimic an industrial perspective, MB adsorption onto RO900 was also carried out in continuous mode. The initial dye concentration and effluent flow rate were among the process parameters that were optimized using the continuous mode of operation. Further, the experimental data of continuous mode was fitted with Clark, Yan, and Yoon-Nelson models. Py-GC/MS investigation revealed that dye-loaded adsorbents could be pyrolyzed to produce valuable chemicals. The cost and low toxicity associated benefits of discarded RO-carbon over other adsorbents reveal the significance of the present study.
Topics: Wastewater; Carbon; Coloring Agents; Adsorption; Water Pollutants, Chemical; Kinetics; Thermodynamics; Methylene Blue; Osmosis; Hydrogen-Ion Concentration
PubMed: 37196691
DOI: 10.1016/j.envres.2023.116165 -
ACS Applied Bio Materials Oct 2023A formate (HCOO) bioanode was developed by utilizing a phenothiazine-based electropolymerized layer deposited on sucrose-derived carbon. The electrode modified with...
A formate (HCOO) bioanode was developed by utilizing a phenothiazine-based electropolymerized layer deposited on sucrose-derived carbon. The electrode modified with NAD-dependent formate dehydrogenase and the electropolymerized layer synergistically catalyzed the oxidation of the coenzyme (NADH) and fuel (HCOO) to achieve efficient electron transfer. Further, the replacement of carbon nanotubes with water-dispersible sucrose-derived carbon used as the electrode base allowed the fabrication of a surfactant-free bioanode delivering a maximum current density of 1.96 mA cm in the fuel solution. Finally, a separator- and surfactant-free HCOO/O biofuel cell featuring the above bioanode and a gas-diffusion biocathode modified with bilirubin oxidase and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) was fabricated, delivering a maximum power density of 70 μW cm (at 0.24 V) and an open-circuit voltage of 0.59 V. Thus, this study demonstrates the potential of formic acid as a fuel and possibilities for the application of carbon materials in bioanodes.
Topics: Surface-Active Agents; Bioelectric Energy Sources; Nanotubes, Carbon; Formates; Phenothiazines; Sucrose
PubMed: 37750824
DOI: 10.1021/acsabm.3c00502