Triphenylmethane Dyes Research Articles

Oxidative removal of Fast Green FCF and ponceaux 4R dyes by H2O2/NaHCO3, UV and H2O2/UV processes: A comparative study

In this work, we explored the use of reactive oxygen species generated by either bicarbonate activated hydrogen peroxide (BAP), UV and UV/H2O2 system for degradation of triarylmethane dye, Fast Green FCF (FG), and azo dye Ponceau 4R (P4R). The degradation rate constant is supposed to be a pseudo-first-order. By bicarbonate activated peroxide (BAP) system which generates hydroxyl radicals and superoxide anion radical (O2-) able to attack the dyes molecules, in 20 min the conversions ware up to 65% for FG and 50% for P4R, respectively. The most efficient degradation is achieved through UV irradiation in the presence of hydrogen peroxide, where the kinetic constants increase by an order of magnitude for both dyes. The total organic carbon (TOC) data showed that for chemical oxidation of FG, the mineralization degree is 86% instead in the case of P4R, the chemical oxidation with BAP system does not lead to mineralization (mineralization degree is about 5%). In the mixture, the degradation of dyes in the BAP system occurs with higher rates for both dyes; in the photolysis, the degradation of FG is slightly increased in the mixture, while the degradation of P4R is much slower. In the case of the UV/H2O2 system, the degradation of both dyes is slower in the mixture. The results obtained by HPLC-MS led to the identification of some organic intermediates and a plausible reaction mechanism for FG and P4R degradation process was proposed.

Influence of Methyl Groups in Triphenylmethane Dyes on Their Adsorption on Biochars from Coffee Husks

Influence of Methyl Groups in Triphenylmethane Dyes on Their Adsorption on Biochars from Coffee Husks

Biodegradation of malachite degradation by laccsae from Bacillus licheniformis NS2324

Malachite green, a triphenylmethane dye, is used in aquaculture to limit the growth of protozoans and fungi in fish. It is also employed in the food, medicinal, and textile sectors. MG has high toxicity covering micro organisms and higher eukaryotes. Its toxic effects include organ damage, developmental abnormalities and mutagenic/carcinogenic potentials. Hence it is of utmost importance to degrade MG. Therefore, in this study with the help of catalytic properties of laccase, biodegradation of dye-malachite green was studied with respect to different factors like temperature, pH, enzyme dose and treatment time. The maximum of 99.31±0.97% MG decoloration was obtained under the conditions of 10 U ml-1 enzyme, pH 8.0 incubation time 1h and a temperature of 50°C. MG was degraded without any mediator of laccase in the current study.

A visible light-response La-doped MnIn2S4 with enhanced performance for removing tetracycline hydrochloride and triphenylmethane dyes in wastewater

Impurity element doping is widely considered to be one of most efficient methods to adjust the electronics construction and the photocatalyst photo-generated separation of charge. In this work, a series of novel flower-like La-doped MnIn2S4 photocatalysts (x wt% La-doped MnIn2S4, x = 0, 5, 10, 20, 30) were prepared by hydrothermal synthesis and adopted various analysis techniques. The results showed that La-doped MnIn2S4 manifested significant photocatalytic performance for the photodegradation of tetracycline hydrochloride (TCH) and triphenylmethane dyes. The removal efficiency of malachite green (MG) and TCH reach 98.1% and 97.9% in 60 min, respectively. In the presence of visible light, the apparent reaction rate of 10 wt% La-doped MnIn2S4 (10 L-MIS) obtained 0.1237 min−1, approximately 13 times that of MIS. The mechanism of photocatalytic degradation has been established that •O2− is the primary active species in the degradation process. At the same time, by researching the antibacterial activity of La-doped MnIn2S4, both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus are resistant to the antibacterial capabilities of the La-doped MnIn2S4 nanocomposite material. The Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus were selected to study the antibacterial activity of La-doped MnIn2S4. The antibacterial results reflect that the synthesized La-doped MnIn2S4 nanocomposite material has excellent antibacterial properties. For the sake of verifying the low toxicity of La-doped MnIn2S4, HCT-116 and HEB were used to investigate the cytotoxicity of La-doped MnIn2S4. Due to the synergistic effect of increased visible-light absorption ability and favorable photogenerated charge carrier separation, the photoactivity of doped MnIn2S4 was significantly increased. The developed La-doped MnIn2S4 nanocomposite materials present high-efficiency photocatalytic activity and have broad application prospects in wastewater and pollutant treatment.

Residues of veterinary drugs in fish and fish products: An analysis of RASFF data over the last 20 years

An analysis of the notifications in the European Union (EU) Rapid Alert System for Food and Feed (RASFF) portal due to residues of veterinary drugs in fish and fish products over the period 2001–2021 was conducted examining the following data: number and type of notifications; year of notification; notification basis; notifying country; country of origin; action taken; distribution status; risk decision; fish product type; residue found. A total of 292 notifications were found (mean number/year 9.8 ± 13.8 SD), mostly information notifications (60.9%). The most common notification basis was “border control - consignment detained” (38.4%), followed by “official control on the market” (37.9%) and “border control - consignment released” (13.7%). Over half (54.1%) of the notifications were issued by the United Kingdom, Germany and Spain, dominant countries in the fish processing market. Thirty-one countries of origin were recorded, but 48.6% of the notifications were referred to products from Vietnam, followed by China (15.7%), that are among the leading fish producing countries. The most common actions taken were re-dispatch (23.3%), followed by recall from consumer (10.3%), withdrawal from recipients (9.9%), destruction (9.6%), and import not authorised (9.2%). Overall, 28.8% of the notifications involved fish products belonging to the Pangasiidae family ( Pangasius spp. and Pangasianodon spp.), followed by tilapia (12.7%), trout (11.0%), eel (8.6%), catfish (7.9%) and salmon (3.4%). Triphenylmethane dyes and their metabolites were the most frequent category of residues found, accounting for 51.4% of the total notifications, followed by a wide range of antibiotics classes, of which nitrofurans and metabolites (19.5%) were the most common, while amphenicols (6.8%), quinolones and fluoroquinolones (6.5%), sulphonamides and potentiators (5.1%), tetracyclines and metabolites (3.4%) and other classes were less represented. Avermectins and unspecified residues were also found in a few cases (2.7%). The annual frequency of these issues varied and was probably influenced by dedicated monitoring plans, as well as by specific sanitary problems occurring in farms. Nevertheless, by providing historical trends and current issues, our analysis identified hazards to be closely monitored, through coordinated official controls especially in the most involved countries. • 20 years of RASFF notifications for veterinary drugs residues in fish products were analysed. • Triphenyl-methane dyes were the most frequent residue found (51.4% notifications). • Several antibiotics classes were found, mainly nitrofurans (19.5% of the notifications). • Historical and current issues to be specifically monitored were pointed out.

Quantification of twenty pharmacologically active dyes in water samples using UPLC-MS/MS

This study presents a multi-compound method for the determination of 20 pharmacologically active dyes from 5 different chemical classes in environmental water samples. These compounds, including triphenylmethane dyes (malachite green, crystal violet, brilliant green, ethyl violet, methyl violet 2B, pararosaniline, victoria blue B, victoria blue R, victoria pure blue BO), phenothiazine dyes (methylene blue, azure A, azure B, azure C, new methylene blue, thionine), phenoxazine dye (nile blue A), acridine dyes (acriflavine, proflavine) and xanthene dyes (rhodamine B, rhodamine 6G) constitute pharmacologically active substances (PASs). For the optimisation of sample preparation, different solid-phase extraction (SPE) sorbents and a wide range of pH (from 2 to 12) of water samples were tested. Finally, water samples were preconcentrated and cleaned up on diol SPE cartridges. Extracts were analysed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) operating in the positive electrospray ionisation (ESI+) mode. The chromatographic separation of the 20 pharmacologically active dyes was achieved within 5 min by using a pentafluorophenyl (F5) analytical column and mobile phases of ammonium acetate buffer (0.05 M, pH = 3.5) and acetonitrile with gradient elution. The developed method was validated proving to be suitable for the determination of all tested compounds. Limits of quantification were 0.01–0.1 μg/l, are sensitive enough to quantify very low concentration levels of the dyes in environmental water samples. The obtained recovery values for all tested analytes were between 71.2 and 104.9% with a good RSD, less than 14 % at all fortification levels. The application of the developed method to water samples allows the detection of dyes such as crystal violet, rhodamine B, and methyl violet in two wastewater samples in concentration range from 0.017 to 0.0043 μg/l).

CO2 to CO Electroreduction, Electrocatalytic H2 Evolution, and Catalytic Degradation of Organic Dyes Using a Co(II) meso-Tetraarylporphyrin.

The meso-tetrakis(4-(trifluoromethyl)phenyl)porphyrinato cobalt(II) complex [Co(TMFPP)] was synthesised in 93% yield. The compound was studied by 1H NMR, UV-visible absorption, and photoluminescence spectroscopy. The optical band gap Eg was calculated to 2.15 eV using the Tauc plot method and a semiconducting character is suggested. Cyclic voltammetry showed two fully reversible reduction waves at E1/2 = −0.91 V and E1/2 = −2.05 V vs. SCE and reversible oxidations at 0.30 V and 0.98 V representing both metal-centred (Co(0)/Co(I)/Co(II)/Co(III)) and porphyrin-centred (Por2−/Por−) processes. [Co(TMFPP)] is a very active catalyst for the electrochemical formation of H2 from DMF/acetic acid, with a Faradaic Efficiency (FE) of 85%, and also catalysed the reduction of CO2 to CO with a FE of 90%. Moreover, the two triarylmethane dyes crystal violet and malachite green were decomposed using H2O2 and [Co(TMFPP)] as catalyst with an efficiency of more than 85% in one batch.

Light-driven bio-decolorization of triphenylmethane dyes by a Clostridium thermocellum-CdS biohybrid

Widespread application of synthetic dyes could generate colored wastewaters causing a range of serious environmental problems. Due to the complex nature of effluents from textile industries, it is difficult to obtain satisfactory treatment of dyes-contaminated wastewater using one single method. Biohybrids coupling of photocatalysts and biocatalysts have great potential in environmental purification. However, how to select suitable organisms and enhance the hybrid’s catalytic activities remain challenging. Here, a novel biohybrid system (Clostridium thermocellum-CdS), created for light-driven biodecolorization under thermophilic treatment by using non-photosynthetic microorganism C. thermocellum self-photosensitized with CdS nanoparticles was established. The biohybrids exhibited remarkable decolorization effects on triphenylmethane dyes. The highest decolorization rate was 0.206 min−1. More importantly, enhanced catalytic activities of cadmium sulfide (CdS)-based biohybrids by controlling the particle sizes of semiconductors were demonstrated. Biohybrids systems (Clostridium thermocellum-CdS) through the self-precipitation of CdS with different particle sizes not only showed dramatic changes in the optical properties but also exhibited a very different decolorization rate. This work can not only further broaden targeted applications of CdS-based biohybrids but also demonstrate a promising route for improving biohybrids corresponding photocatalytic capabilities through in situ precipitation CdS with different particle sizes.

Anthraquinone acted as a catalyst for the removal of triphenylmethane dye containing tertiary amino group: Characteristics and mechanism

Herein, we found that anthraquinone (AQ) acted as a catalyst for the rapid and effective removal of triphenylmethane dye containing tertiary amino group (TDAG). Results showed that AQ had an enhanced catalytic reactivity towards the removal of TDAG compared to hydro-quinone, which was further proved and explained using density functional theory (DFT) calculations. AQs could achieve a TDAG removal efficiency and rate of approximately 100% and 0.3583 min−1, respectively, within 20 min. Quenching experiments and electron paramagnetic resonance (EPR) tests indicated that the superoxide radical (O2•−) generated through the catalytic reduction of an oxygen molecule (O2) by AQ contributed to the effective removal of the TDAG. In addition, it was found that the electrophilic attack of the O2•− radical on the TDAG was the driving force for the dye degradation process. Decreasing the pH led to protonation of the substituted group of AG, which resulted in formation of an electron deficient center in the TDAG molecule (TDAG-EDC+) through delocalization of the π electron. Therefore, the possibility of the electrophilic attack for the dye by the negative O2•- radical was significantly enhanced. This study revealed that the H+ and the O2•− generated by the catalytic reduction of O2 have synergistic effects that led to a significant increase in the dye removal rate and efficiency, which were higher than those obtained through persulfate oxidation.

Investigation on the by-pass line orifice plate assisted hydrodynamic cavitation (B-PLOPA HC) degradation of basic fuchsin (BF) in wastewater

HC technology has been widely used in the field of wastewater treatment due to its advantages of simple operation, low operating cost and large treatment capacity. However, the conventional HC devices that rely solely on the main line cavitator to treat organic pollutants show unsatisfactory degradation effect. Therefore, it is difficult to enhance the degradation effect of organic pollutants only by optimizing the cavitator geometry and experimental operation parameters. In fact, for traditional HC device the pressure in front of the throttle valve in the by-pass line is same as the inlet pressure of the main line cavitator. In this study, the orifice plate cavitator is firstly used to replace the throttle valve in the by-pass line of the traditional HC device to form a by-pass line orifice plate assisted hydrodynamic cavitation (B-PLOPA HC) device after optimizing the cavitator geometry and experimental operation parameters, realizing the synchronous occurrence of HC effects in the main and by-pass line cavitator and greatly enhancing the degradation effect of organic pollutants. A triphenylmethane dye, basic fuchsin, is used as the simulated pollutant to carry the degradation experiment by using an improved HC device. It was found that, under inlet pressures of 3.0, 4.0 and 5.0 bar within 90 min, the degradation ratios of basic fuchsin were increased from 59.72 %, 73.60 % and 65.23 % by using conventional HC device to 80.93 %, 81.15 % and 81.38 % by using B-PLOPA HC device, respectively. Correspondingly, the wastewater treatment costs were reduced by 41.82 %, 26.16 % and 29.87 %, respectively, compared with those before modification. Obviously, such modification not only enhances the degradation effect of organic pollutants, but also reduces the cost of wastewater treatment. Besides, the active substances generated in B-PLOPA HC system were explored by adding free radical trapping agent. According to the determined results from Liquid Chromatograph Mass Spectrometer (LC-MS) and Total Organic Carbon (TOC), the possible degradation path of basic fuchsin is proposed. In a word, the overall HC effect of system is effectively strengthened through the use of the by-pass line orifice plate. This study provides a solid theoretical basis for large-scale application of HC technology in the field of wastewater treatment.© 2021 Elsevier Ltd. All rights reserved.

Magnetic casein aggregates as an innovative support platform for laccase immobilization and bioremoval of crystal violet

In this study, casein@CoFe2O4 was fabricated through a green synthesis methodology and applied to immobilize laccase. The constructed casein@CoFe2O4 exhibited porous structures with distinct cavities and suitable magnetic properties. The abundance of aromatic functional groups on the surface renneted casein and possible π-type interaction between laccase and para-κ-casein resulted in a successful immobilization. The biocatalyst retained 50% of its initial activity after 24 reusability cycles, indicating stable immobilization of laccase onto the casein microstructures. The stability of laccase after immobilization was improved by 300% in comparison with the free enzyme, especially in basic pH values. The constructed laccase@casein@CoFe2O4 was then incorporated to remove crystal violet (CV) as an environmentally harmful synthetic tri-phenylmethane dye. The prepared heterogeneous biocatalyst effectively diminished the antimicrobial activity of CV up to 81.3% in 40 min against some bacterial strains, resulting from the formation of more minor toxic metabolites identified by liquid chromatography coupled with mass spectroscopy after degradation procedure. The proposed green and feasible method for the preparation of magnetic casein aggregates has not been previously reported. The incorporation of casein, which acted as a molecular chaperon, resulted in a significant improvement in the enzymatic stability and exhibited appropriate reusability for the constructed biocatalytic system.

A Visible Light-Response La-Doped Mnin2s4 with Enhanced Performance for Removing Tetracycline Hydrochloride and Triphenylmethane Dyes in Wastewater

A Visible Light-Response La-Doped Mnin2s4 with Enhanced Performance for Removing Tetracycline Hydrochloride and Triphenylmethane Dyes in Wastewater

Uncovering mechanisms of RT-LAMP colorimetric SARS-CoV-2 detection to improve assay reliability

In this study, we enhanced the color changes and sensitivity of colorimetric SARS-CoV-2 RT-LAMP assays based on triarylmethane dyes. We determined a mechanism for the color changes and obtained sensitivities of 10 RNA copies per microliter.

Bioremediation of the Triphenylmethane Dye Brilliant Green by a Newly Isolated Bacterial Consortium of Alcaligenes Sp. Sy1 and Enterobacter Asburiae Strain Sg43

Bioremediation of the Triphenylmethane Dye Brilliant Green by a Newly Isolated Bacterial Consortium of Alcaligenes Sp. Sy1 and Enterobacter Asburiae Strain Sg43

Fabrication of Novel Porous Zif-67/Pes Composite Microspheres and the Efficient Adsorption of Triphenylmethane Dyes from Water

Fabrication of Novel Porous Zif-67/Pes Composite Microspheres and the Efficient Adsorption of Triphenylmethane Dyes from Water

Nanoconfinement – amplified, Förster resonance energy transfer in nile red – borne mesoporous silica for ultrasensitive, multiplex assay of triphenylmethane dyes in aqueous milieu

Mesoporous silica is utilized for sub-ppb-level Förester resonance energy transfer-based detection of triphenylmethane dyes in water.

Ag Nanoaprticles Anchored in the Flower-Like of Aluminum/Carbon Nitride for Selective Raman Detection and Photocatalytic Degradation of Triphenylmethane Dyes

Ag Nanoaprticles Anchored in the Flower-Like of Aluminum/Carbon Nitride for Selective Raman Detection and Photocatalytic Degradation of Triphenylmethane Dyes

Selective Raman Detection and Photocatalytic Degradation of Triphenylmethane Dyes Based on Ag Nanoaprticles Anchored in the Flower-Like of Aluminum/Carbon Nitride

Selective Raman Detection and Photocatalytic Degradation of Triphenylmethane Dyes Based on Ag Nanoaprticles Anchored in the Flower-Like of Aluminum/Carbon Nitride

Oxidative Degradation of Brilliant Green by Potassium Iodate in Acidic Medium: A Kinetic and Mechanistic Study

Brilliant green (BG), one of the triphenylmethane dyes, has been extensively applied and produced as a colorant for different industries like medical, paper/textile printing, food additive, cosmetics, etc. Dyes effluents discharged by these industries pose hazardous effects on environmental and human health via releasing toxic and carcinogenic contaminants during its deterioration. The present work evaluates kinetic and mechanistic aspects of oxidative degradation of brilliant green by iodate in acidic solution at 303 K. The influence of different factors such as concentration of various reactants (μ), free radicals, etc. has also been investigated to check feasibility of redox degradation for efficient, easy, low-cost and eco-friendly removal of brilliant green from aquatic medium. The experimental result shows a first-order rate dependence on [BG] and zero-order kinetics with respect to [KIO3]. The reaction showed positive fractional order dependence on the rate for [H+]. Variations in ionic strength of the medium and [Cl–] did not bring about any noticeable change on the rate of reaction. It was found that the reaction rate declined with the decrease in the dielectric constant (D) of the medium in the oxidation of brilliant green. Additionally, the process was carried out at different temperatures to estimate the activation parameters and also to find rate controlling stages of the process. Finally, an appropriate mechanism, a plausible with the experimental observations, also supported by UV-Vis spectra has been proposed.

A Method of Sample Preparation in the Determination of Water-Soluble Triarylmethane Dyes

A Method of Sample Preparation in the Determination of Water-Soluble Triarylmethane Dyes