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Vermiculite is extensively utilized for several applications, including as a hydroponic substrate, for soil conditioning, oil cleansing, and addressing trace metal pollution. In this study, the expansion of natural vermiculite was easily achieved by utilizing hydrogen peroxide (H2O2) with the aid of microwave technology. The characterization of expanded vermiculite involved the use of X‐ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), nitrogen adsorption isotherm (BET), and energy dissipation X‐rays (EDX). The vermiculite has been enlarged to have a structure resembling flakes, and its surface area measures 73.9 m2/g. The adsorption of Alizarin Red S onto expanded vermiculite was investigated under varying conditions, such as pH, starting concentration, adsorbent content, and duration of exposure. The enlarged vermiculite achieved a maximum adsorption capacity of 182.5 mg/g for Alizarin Red S. Out of the three adsorption isotherm models, both the Freundlich and Temkin models accurately describe the adsorption of Alizarin Red S onto expanded vermiculite. When studying adsorption kinetics, the second‐order adsorption kinetic model is more appropriate than the first‐order adsorption kinetic model, as indicated by an R2 value of 0.8964. [ABSTRACT FROM AUTHOR]

The presented work focused on the preparation of a voltammetric sensor for hydroquinone (HQ) determination using a polycrystalline platinum electrode modified with Alizarin Red S (ARS). The electrode was prepared by electropolymerization of ARS on a platinum electrode through the application of 100 cyclic voltammetric segments between –0.4 and 1.2 V against Ag/AgCl (quasi-reference electrode). The modified poly (ARS)-Pt electrode was characterized in terms of stability and cyclic voltammetric behavior as a sensor for HQ in aqueous media. The modified electrode showed excellent stability and higher current than the unmodified electrode for the electrooxidation of HQ. Thus, the oxidation of HQ at poly (ARS)-Pt electrode exhibits notable electrocatalytic performance. The limit of detection is 0.16 µM, and the standard curve exhibits a linear relationship over the range from 0.25 to 15 µM (R2 = 0.999). Investigation of the response to some potential interferences indicated that the electrode is unresponsive to Na+, K+, Mg2+, Ca2+, Zn2+, Mn2+, Mo2+, Co2+, Bi2+, Cd2+, Ni2+, Al3+, , , Cl–, phenol and resorcinol, but shows marginal change towards Hg2+ and Cu2+. Recovery tests indicated recovery values between 97.0% and 100.81% when analyzing real samples at the modified electrode. [ABSTRACT FROM AUTHOR]

The present work aimed to highlight an efficient, readily accessible, and costeffective adsorbent derived from Dalbergia sissoo (DS) leaf powder for removing the environmentally hazardous dye "alizarin red S" (ARS) from hydrous medium. A variant of the adsorbent is activated via sulfuric acid and composited with magnetic iron oxide nanoparticles (DSMNC). Both adsorbents are thoroughly characterized using techniques such as Fourier transform infrared spectroscopy, point of zero charge, energy-dispersive X-ray spectroscopy, and scanning electron microscopy, which show that they have a porous structure rich in active sites. Different adsorption conditions are optimized with the maximum removal efficiency of 76.63% for DS and 97.89% for DSMNC. The study was highlighted via the application of various adsorption isotherms, including Freundlich, Langmuir, Temkin, and Dubinin-Radushkevich, to adsorption data. Pseudo-first-order, pseudo-second-order, and intra-particle diffusion models were utilized to investigate the kinetics and mechanism of adsorption. The Freundlich model and pseudo-second-order kinetics exhibited the best fit, suggesting a combination of physical interactions, as confirmed by the D-R and Temkin models. The dominant adsorbate-adsorbent interactive interactions responsible for ARS removal were hydrogen bonding, dispersion forces, and noncovalent aromatic ring adsorbent pi-interactions. Thermodynamic parameters extracted from adsorption data indicated that the removal of the mutagenic dye "ARS" was exothermic and spontaneous on both DS and DSMNC, with DSMNC exhibiting higher removal efficiency. [ABSTRACT FROM AUTHOR]

In this study, the pressing issue of persistent organic pollutants in wastewater was addressed by designing and fabricating a magnetically separable MnFe2O4/rGO heterostructure catalyst for efficient mineralization of bisphenol A (BPA) and dyes such as alizarin red S (anionic) and malachite green (cationic), which are known for their resistance to biodegradation and carcinogenic properties. Comprehensive structural and surface analyses using XRD, XPS, SEM, and TEM/HRTEM coupled with magnetic and optical property measurements revealed the formation of the MnFe2O4/rGO heterostructures. Among all, the MnFe2O4/rGO-10 catalyst with 10% wt% of rGO exhibited 100% efficiency in the mineralization of BPA and both dyes under visible light illumination within 60 min. The stability and recyclability of the catalyst, assessed through XRD and VSM studies, demonstrated its consistent performance over multiple uses. The cost-effectiveness and stability of this catalyst underscore its potential for practical application in wastewater treatment, offering a viable solution to the persistent challenge of removing stubborn organic contaminants. [ABSTRACT FROM AUTHOR]

Accurate age estimation is essential for population dynamics modeling and fisheries management. Otoliths serve as a critical resource for age determination in ichthyological studies, capitalizing on the embedded growth increments. The periodicity of these increments, however, requires thorough validation to confirm the accuracy of age assessments. This study validated daily increment deposition in sagittal otoliths of young-of-year Pagellus acarne from Çanakkale, Turkey using Alizarin Red S (ARS), a fluorescent calcium-binding marker. Specimens (n=107; 1.8-4.7cm TL) were exposed to ARS concentrations of 0 (control), 50, 100, 150, 200, and 300mg/L for 24h, then reared 13 days. After a recovery period of 13 days, the second dyeing was performed with the aim of having a specific fluorescent mark to test the 13 rings found between the 2 fluorescent marks. Otoliths were examined under fluorescent microscopy. ARS marks were detectable in 81.57% of otoliths at ≥100mg/L, with the highest visibility at 300mg/L. Survival exceeded 84.2% across treatments. Increment counts between the first and second ARS marks (13 days) and from the second mark to the edge (20 days) matched elapsed time. Ages from wild fish (n=95) ranged 39-201 days with a growth rate of 0.176mm/day. This research demonstrates ARS is an effective, low-impact tool for periodicity validation and provides the basis for accurate age determination and population modeling of this ecologically important species in the region. [ABSTRACT FROM AUTHOR]

Background: The individual teratogenicity profiles of Lumacaftor and Ivacaftor are known, but the combined effects remain unexplored. Purpose: To evaluate the teratogenic profile of a combination of Lumacaftor and Ivacaftor in Sprague-Dawley Rats. Materials and Methods: This study adhered to the Committee for Control and Supervision of Experiments on Animals (CCSEA) and Organisation for Economic Co-operation and Development (OECD) guidelines. Sprague–Dawley rats were acclimated and housed individually under controlled conditions. A polygamous breeding scheme was implemented, and pregnant female rats were assigned to control, vehicle control or treatment group following OECD Test Guideline 414. Lumacaftor and Ivacaftor were administered to pregnant rats at various doses, such as MRHD, 5MRHD, 8MRHD and 10MRHD, from gestation days 6 to 17. Clinical observations, body weight and food consumption of pregnant rats were monitored. Postmortem examinations included caesarean section, reproductive performance (the number of corpora lutea, implantation sites, early and late resorptions and live foetuses) and assessment of foetal analysis. The foetal analysis incorporated external malformation evaluation, visceral examination and skeletal examination using alizarin red solution. Results: In pregnant rats exposed to Lumacaftor and Ivacaftor, the external examination was conducted on 206, 209, 199, 184, 198 and 201 foetuses in their respective groups, each consisting of 19 litters. Within this cohort, approximately 33% of foetuses underwent visceral examination. Additionally, across six groups approximately 50% of foetuses underwent skeletal examination. Importantly, no abnormalities were detected in skeletal, visceral or histopathological assessments across the treatment groups encompassing doses of a combination of Lumacaftor and Ivacaftor at MRHD, 5MRHD, 8MRHD and 10MRHD. Additionally, no significant morbidity or mortality related to the treatment was observed. Conclusion: In conclusion, the study indicates that the combination of Lumacaftor and Ivacaftor at doses equivalent to MRHD, 5MRHD, 8MRHD and 10MRHD did not induce significant teratogenic effects, affirming their safety during pregnancy in rats. [ABSTRACT FROM AUTHOR]

The present work aimed to highlight an efficient, readily accessible, and cost-effective adsorbent derived from Dalbergia sissoo (DS) leaf powder for removing the environmentally hazardous dye “alizarin red S” (ARS) from hydrous medium. A variant of the adsorbent is activated via sulfuric acid and composited with magnetic iron oxide nanoparticles (DSMNC). Both adsorbents are thoroughly characterized using techniques such as Fourier transform infrared spectroscopy, point of zero charge, energy-dispersive X-ray spectroscopy, and scanning electron microscopy, which show that they have a porous structure rich in active sites. Different adsorption conditions are optimized with the maximum removal efficiency of 76.63% for DS and 97.89% for DSMNC. The study was highlighted via the application of various adsorption isotherms, including Freundlich, Langmuir, Temkin, and Dubinin–Radushkevich, to adsorption data. Pseudo-first-order, pseudo-second-order, and intra-particle diffusion models were utilized to investigate the kinetics and mechanism of adsorption. The Freundlich model and pseudo-second-order kinetics exhibited the best fit, suggesting a combination of physical interactions, as confirmed by the D–R and Temkin models. The dominant adsorbate–adsorbent interactive interactions responsible for ARS removal were hydrogen bonding, dispersion forces, and noncovalent aromatic ring adsorbent pi-interactions. Thermodynamic parameters extracted from adsorption data indicated that the removal of the mutagenic dye “ARS” was exothermic and spontaneous on both DS and DSMNC, with DSMNC exhibiting higher removal efficiency.

This study assessed the otolith (sagittae, lapilli, and asterisci) increment deposition rate in the range‐shifting damselfish, A. vaigiensis, using different concentrations of Alizain Red S and evaluated the impact of staining on increment width. Daily increment deposition was verified in all otolith types and presented clearer fluorescent markings in the lapilli and sagittae than the asterisci, with high stain concentration showing the best clarity. Higher stain concentrations were found to decrease increment width, suggesting care is needed when using stained otoliths as a proxy for growth for this species. [ABSTRACT FROM AUTHOR]

In the current work, a rapid, selective, and sensitive technique was developed for the detection of Alizarin Red S (ARS) by applying poly leucine modified carbon paste electrode (PLMCPE). Electrochemical impedance spectroscopy (EIS) and Scanning electron microscopy (SEM) were utilized to study the surface morphology of unmodified carbon paste electrode (UMCPE) and PLMCPE. The active surface area for UMCPE and PLMCPE was found to be 0.0012 cm2 and 0.0026 cm2 respectively. The electrochemical response of ARS at UMCPE and PLMCPE was analyzed using cyclic voltammetry (CV) in the potential window of 0.4 to 1.0 V. The cyclic voltammogram obtained for varying the pH of 0.2 M phosphate buffer (PB) solution showed maximum current for the oxidation of ARS at pH 6.5. The electrochemical reaction of ARS was found to be irreversible and adsorption controlled. The effect of variation of concentration of ARS on the oxidation peak current was evaluated using CV and linear scan voltammetry (LSV). A linear relationship between the concentration variation and current was obtained in the linear range of 1.5 μM–3.5 μM and 0.2 μM–5.0 μM for CV and LSV respectively. The limit of detection (LOD) of 0.68 μM for the CV method and 0.29 μM for the LSV method was exhibited by the developed sensor. The simultaneous study of ARS along with tartrazine (TZ) showed good selectivity for ARS. The interferents of foreign molecules showed no effect on the selectivity of the electrode. The applicability of PLMCPE on real samples gave good recovery ranging from 97.46–101.2%; hence, the sensor can be utilized on real samples. The developed sensor has good stability and sensitivity. [ABSTRACT FROM AUTHOR]

Evaluation of effective and low‐cost materials as catalysts to combat the threat of pollution is a significant and growing trend. With this aim, we have synthesized calcium ferrite brownmillerite by wet preparation approach as a catalyst for pollution. The structural analysis is established by the X‐ray diffraction of Ca2Fe2O5, whereas the tetrahedral and octahedral sites band stretching for ferrite specimen has been deduced using FTIR. The bandgap energy has been estimated by the Tauc relation (2.17 eV). Ca2Fe2O5 brownmillerite exhibits a BET surface area of 10 m2/g and a BJH pore volume of 0.121 cm3/g with the average particle size of 70 nm. Importantly, the alizarin Red S dye degradation has been studied using the prepared ferrite catalyst, under dark ambient conditions and without the presence of any acidic or basic additives. Degradation is also supported by both FTIR and TOC analysis. Surface properties of brownmillerite Ca2Fe2O5 have been characterized using electronic spectroscopy and CO2 temperature programmed desorption (TPD) analysis and revealed that the basic surface of brownmillerite Ca2Fe2O5 offers active sites that are suitable for degradation processes. All results show that the preparation of brownmillerite Ca2Fe2O5 via the Pechini method is suitable to produce fine surfaces and pores with nanosized particles. [ABSTRACT FROM AUTHOR]

Light‐gated chemical reactions allow spatial and temporal control of chemical processes. Here, we suggest a new system for controlling pH‐sensitive processes with light using two photobases of Arrhenius and Brønsted types. Only after light excitation do Arrhenius photobases undergo hydroxide ion dissociation, while Brønsted photobases capture a proton. However, none can be used alone to reversibly control pH due to the limitations arising from excessively fast or overly slow photoreaction timescales. We show here that combining the two types of photobases allows light‐triggered and reversible pH control. We show an application of this method in directing the pH‐dependent reaction pathways of the organic dye Alizarin Red S simply by switching between different wavelengths of light, i. e., irradiating each photobase separately. The concept of a light‐controlled system shown here of a sophisticated interplay between two photobases can be integrated into various smart functional and dynamic systems. [ABSTRACT FROM AUTHOR]

A series of Cu-substituted NiZn ferrite nanoparticles (Ni0.5Zn0.5-xCuxFe2O4; 0 ≤ x ≤ 0.2) were synthesized by the polyol method and then characterized and investigated for their efficiency for the adsorptive removal of Alizarin Red S (ARS) dye as well as for their reusability. The effect of Cu2+ substitution for Zn2+ on the phase formation, crystal structure, microstructure and magnetic properties was investigated. The powders were pure phases with a cubic spinel structure and a slight departure of the unit cell parameter from the expected linearity variation as a function of Cu2 content. The particles are ultrasmall sized nanoparticles (~4–6 nm) with an almost spherical shape. The surface chemistry and the core local structure of the nanoparticles were ascertained from infrared. Magnetic study revealed a superparamagnetic behavior, and the variation observed for the main magnetic characteristics was interpreted on the basis on the changes in chemical composition, cation distribution and nanoparticles morphology. Adsorption–desorption of ARS onto the nanoparticles was investigated by varying various physicochemical parameters. The ferrite member with x = 0.15 exhibited the best removal capacity. At the optimum pH (pH2.0) the adsorption was fast during the first stage of adsorption process. Three kinetic models were tested. The adsorption data were best fitted with the pseudo-second-order model. The adsorption isotherms were measured and analyzed by Langmuir and Freundlich models. Based on Freundlich model, the maximum adsorption capacity was found to be high (~ 181 mg g−1). Besides, good reusability performance was observed after five adsorption–desorption-regeneration cycles. The mechanisms of both adsorption and desorption were proposed. [ABSTRACT FROM AUTHOR]

Nickel (II)–alizarin red S (Ni–ARS) complexes were synthesized using different mole ratios and pH. This study aims to analyze the effect of mole ratio and pH on the resulting complex structure and to determine the relationship between the geometric stability of the complex structure and its antibacterial ability using molecular docking studies. The variation in moles (1:2 and 1:3) did not affect the type or structure of the complex produced, but variations in pH affected the type of complex obtained. The dimer complex was obtained at pH 7 and 8, while the monomer complex was obtained at pH 6. ARS ligand complexation occurred in the carbonyl and hydroxyl (peri-hydroxy carbonyl) groups. DFT studies show that monomeric complexes are more stable than dimeric complexes while confirming a higher yield of monomeric complexes than dimeric complexes. Although DFT calculations show that monomer complexes are more stable than dimers, molecular docking showed antibacterial activity of E. coli and S. aureus from dimer complexes > monomer complexes > ARS. This study concluded that geometric stability is not always directly proportional to its bioactivity ability. [ABSTRACT FROM AUTHOR]

Abstract Evaluation of effective and low‐cost materials as catalysts to combat the threat of pollution is a significant and growing trend. With this aim, we have synthesized calcium ferrite brownmillerite by wet preparation approach as a catalyst for pollution. The structural analysis is established by the X‐ray diffraction of Ca2Fe2O5, whereas the tetrahedral and octahedral sites band stretching for ferrite specimen has been deduced using FTIR. The bandgap energy has been estimated by the Tauc relation (2.17 eV). Ca2Fe2O5 brownmillerite exhibits a BET surface area of 10 m2/g and a BJH pore volume of 0.121 cm3/g with the average particle size of 70 nm. Importantly, the alizarin Red S dye degradation has been studied using the prepared ferrite catalyst, under dark ambient conditions and without the presence of any acidic or basic additives. Degradation is also supported by both FTIR and TOC analysis. Surface properties of brownmillerite Ca2Fe2O5 have been characterized using electronic spectroscopy and CO2 temperature programmed desorption (TPD) analysis and revealed that the basic surface of brownmillerite Ca2Fe2O5 offers active sites that are suitable for degradation processes. All results show that the preparation of brownmillerite Ca2Fe2O5 via the Pechini method is suitable to produce fine surfaces and pores with nanosized particles.

Nanoparticles differ significantly from their bulk counterparts in terms of their characteristics, and they have a wide range of scientific uses. The use of green nanoparticles have received considerable attention. Recent advances in green nanomaterial production have made it possible to utilize these materials in catalysis. Many techniques have been applied to treat the textile wastewater. In the current study, Alizarin Red S dye is photocatalytically degraded utilizing green synthesized NiO nanoparticles derived from green tea extract. Utilizing techniques such as FT-IR, UV-Visible spectroscopy, EDAX, SEM, and XRD, the synthesized nanoparticles were examined. The morphology of the nanoparticle was studied using the SEM images. The XRD analysis was used to find the size of the crystal. The formula developed by Debye Scherer was used to determine the crystallite size. It was seen that the crystallite size was 29.75 nm. Using EDAX, the existence of Ni was verified. FT-IR analysis was used to find the functional groups present in the nanoparticle. According to morphological research, the nanoparticles are flake-shaped and have a larger surface area. Systematically the impact of many parameters on dye degradation, including catalyst dosage, dye concentration, and pH was examined. The findings showed that NiO can be used as a good nanocatalyst to degrade organic dyes. The kinetics of photodegradation were studied. Antibacterial and antifungal activities carried out on the synthesized nanoparticle and the precursor green tea shows that they have good activity over bacteria and fungi. The right selection of operating conditions allows to degrade the pollutant effectively.

Aluminium is preferred over iron for various uses as it is lighter, rust-proof and has an exceptional strength-to-weight ratio. Aluminium is more reactive than iron because of its higher standard reduction potential but it forms a self-protective layer of Al2O3 due to its higher reducing potential. Still, aluminium is corroded in acidic and alkaline media. The present research paper reports the corrosion behaviour of aluminium in 0.1 M NaOH solution with Alizarin Red S (ARS) or Xylenol Orange (XO) as an inhibitor. Corrosion potential, Corrosion current, Tafel slopes (βc) and (βa) for aluminium corrosion have been potentiodynamically investigated. The weight loss method has also been used to calculate the inhibition efficiencies of these additives. The corroded surfaces have been characterized by SEM images. It is found that corrosion potential values change significantly towards the anodic direction in the presence of ARS but they are sifted towards a cathodic direction at a high concentration of XO. While ARS shows a corrosion inhibition effect, XO shows a reverse effect. The inhibition efficiency values of ARS and XO calculated from corrosion current in potentiodynamic polarization studies tally with those calculated from weight loss studies. Studies on a laboratory model of aluminium-air batteries in 0.1 M NaOH containing these organic additives show that the discharge curve of the cell is improved in the presence of ARS and XO in combination. The results are explained in terms of the formation of well-known Al+3.3ARS− and Al+3-XO6− complexes. At room temperature, 1.0 × 10−3 M solution of ARS is found effective in inhibiting the corrosion of aluminium while the same concentration of XO is acting as a corrosion accelerator. This interesting study can be very vital in the field of corrosion science.

The use of conductive polymers as an adsorbent has gained attention as a potentially effective treatment for environmental issues owing to their high adsorption capacity, adjustable surface characteristics, sustainability, environmental stability, ease of application, low toxicity, and low cost. In this study, PANI/PTh was synthesized and its adsorption properties were investigated for the first time. The copolymer was utilized for the adsorption of the ARS and 2NSA. Langmuir isotherm was determined to be the most applicable for the sorption of ARS and 2NSA on the PANI/PTh. Maximum adsorption capacities from this isotherm were determined as 4629.6 and 3021.2 mg/g for ARS and 2NSA, respectively. Moreover, different kinetics were applied to the sorption data and it was found that both studies followed the PSO kinetic. Additionally, from the intraparticle diffusion and Avrami kinetic, the existence of more than one adsorption mechanism was determined. Thermodynamic parameters were calculated by adsorption studies performed at different temperatures. According to enthalpy values, it was determined that ARS (-7.22 kJ/mol) and 2NSA (-26.92 kJ/mol) adsorption were exothermic indicating both ARS and 2NSA adsorption occurred spontaneously. All of the results demonstrated that the PANI/PTh is a promising adsorbent for the removal of various contaminants from wastewater. [ABSTRACT FROM AUTHOR]

The influence of phosphate buffer on the reaction of boronic acid with 1,2‐diol was studied using a reaction system suitable for kinetics and the reaction of 3‐nitrophenylboronic acid (3‐NO2PhB(OH)2) with alizarin red S. The reaction was accelerated with increasing concentrations of phosphate buffer. 1H and 11B NMR spectra were recorded for four pH‐controlled solutions, each containing different boronic acids, to determine the cause of the reaction rate acceleration. The results indicated that HPO42− interacted with both 3‐NO2PhB(OH)2 and 3‐NO2PhB(OH)3−, whereas H2PO4− hardly interacted with either 3‐NO2PhB(OH)2 or 3‐NO2PhB(OH)3−. The reaction rates were enhanced by the formation of outer‐sphere complexes between RB(OH)2 and HPO42− and RB(OH)3− and HPO42−. [ABSTRACT FROM AUTHOR]

Alizarin red S is a sulfonated, water-soluble derivative of alizarin. This work presents femtosecond studies of alizarin red S (ARS) nanoparticles in comparison to ARS in aqueous solution and to alizarin in DMSO. The femtosecond studies cover a probing spectral range of 350–750 nm using different excitation wavelengths, taking into account the variation of the absorption spectra with the pH values of the solvent. Stationary absorption spectra show slight differences between solution and nanoparticles. Excitation at 530 nm results in low and noisy responses, therefore, we additionally recorded transient spectra of the nanoparticles at λex = 267 nm. While the results in DMSO are comparable to previous studies in non-aqueous solvents, we report a relatively fast relaxation of 14 ps in [La(OH)2][ARS] nanoparticles in aqueous solution after excitation at 530 nm, which is similar to Na(ARS) solution (19 ps). The dynamics changed with lower pH, but still without significant differences between nanoparticles and solution. We propose [La(OH)2][ARS] nanoparticles as a suitable alternative to dissolved molecules with similar spectroscopic properties, for example, with regard to biomarker applications. [ABSTRACT FROM AUTHOR]

This work presents the synthesis of MoO3 and zirconium doped MoO3 nanoparticles by hydrothermal method and their characterizations by several analytical techniques. The XRD patterns of all the undoped and doped samples could be indexed to the hexagonal phase with rod shaped morphologies which were obtained from SEM images. The EDX patterns show the respective elemental composition in the samples thus revealing the effective doping of zirconium into the host lattice of MoO3 without any impurities. The structural features were substantiated by FTIR and Raman spectral studies. The band-gap energies tend to decrease on increasing the dopant concentration. The decrease in PL intensities after doping reveals the lower electron–hole recombination rate which is an important characteristic of photocatalytic studies. The XPS spectra of the NPs were studied to confirm the oxidation state of Zr ions. The doping of zirconium with MoO3 nanoparticles enhanced the photodegradation of Alizarin red S (ARS) in visible region which were studied by varying certain parameters such as catalytic dosage, dye concentration and so on. [ABSTRACT FROM AUTHOR]

Fungi were used as one of the most common bioremediation methods. From this perspective, our study highlights the optimization of Alizarin Red S (ARS) dye adsorption performance for the sodium alginate (SA) by using the fungus Aspergillus terreus (A. terreus) to form a composite bead and the possibility of its reusability. This was accomplished by mixing SA with different ratios of biomass powder of A. terreus, including 0%, 10%, 20%, 30%, and 40%, to form composite beads of A. terreus/SA-0%, A. terreus/SA-10%, A. terreus/SA-20%, A. terreus/SA-30%, and A. terreus/SA-40%, respectively. The ARS adsorption characteristics of these composite mixtures were analyzed at various mass ratios, temperatures, pH values, and initial concentrations. Moreover, sophisticated techniques, such as scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR), were employed to detect the morphological and chemical properties of this composite, respectively. The experimental results revealed that A. terreus/SA-20% composite beads have the highest adsorption capacity of 188 mg/g. Its optimum adsorption conditions were achieved at 45 °C and pH 3. Moreover, the ARS adsorption was well explained by the Langmuir isotherm (qm = 192.30 mg/g) and pseudo-second-order and intra-particle diffusion kinetics. The SEM and FTIR findings corroborated the superior uptake of A. terreus/SA-20% composite beads. Lastly, the A. terreus/SA-20% composite beads can be employed as an eco-friendly and sustainable alternative to other common adsorbents for ARS. [ABSTRACT FROM AUTHOR]

The efficient removal of harmful dyes from wastewater, employing green methods, is a subject of growing interest. Anthraquinone dyes alizarin red (AR) S and methyl orange (MO) were used as model pollutants in this investigation, and magnetic chitosan particles were used to extract them from aqueous solution. SEM–EDX, XRD, FTIR ATR, and TGA DSC were used to examine the physicochemical, thermal, and morphological properties of the synthesized material. The effect of pH, dye concentration, duration, and adsorbent loading on dye degradation was examined. After adsorption, the material could be easily separated with the assistance of an external magnet. The selective adsorption of alizarin red S dye to methyl orange was studied in single and binary solutions. The dye uptake capacity provided by the use of the pseudo-second-order model is higher as compared to the pseudo-first order. The dye was adsorbed at 201.5 mg/g for 120 min. The batch adsorption followed the Freundlich isotherm (R2 = 0.995) with alizarin red adsorption being endothermic with the presence of multimolecular layer adsorption. Desorption efficiency decreases to 90% after the first cycle. For repeated usage, the material proved to be extremely stable and easy to recycle. The adsorption mechanism of AR and MO dye removal by magnetic chitosan adsorbent is proposed. [ABSTRACT FROM AUTHOR]

Spirulina platensis is abundant biomass of cyanobacteria (blue-green algae) which is applied in the current study as a biosorbent. A statistical Box–Behnken approach was adopted to remove the toxic dye of alizarin red S (ARS) from synthetic solutions. A polynomial equation was developed to predict the dye removal efficiency and elucidate the interaction effects of variables. The maximum removal efficiency of ARS (69.1%) was obtained at pH 6.5, mixing time of 42.5 min, dye concentration of 100 mg. L−1 and S. platensis dose of 1.5 g. L−1. The findings indicated that the biosorption rate of ARS had a direct relationship with the ARS concentration, pH, reaction time, and S. platensis dose. The quadratic model suggested that the ARS concentration is the major variable in ARS removal. The isotherms and kinetics data could be suitably reflected by the Langmuir model and the pseudo-first-order equation. The maximum adsorption capacity of S. cerevisiae was obtained to be 17.15 mg. g−1 based on the Langmuir model. The results showed that the removal rates of ARS from the first cycle up to the fourth cycle were varied from 55% to 20%, respectively. In conclusion, S. platensis shows suitable adsorptive characteristics and hence could be suggested as a viable option for future studies. [ABSTRACT FROM AUTHOR]

Environmental pollution by organic pollutants because of population growth and industrial expansion is a global concern. Following this, the fabrication of single and efficient nanomaterials for pollution control is highly demanded. Under this study, highly efficient and stable copper oxide nanoparticles (CuO NPs) were synthesized through the green method using Moringa stenopetala seed extract. XRD, UV–vis, FT-IR, and SEM were applied to characterize the synthesized material. From XRD data, the average particle size was found to be 6.556 nm, and the nanoparticles are crystalline in nature. The formation of CuO NPs was demonstrated by FT-IR spectra of Cu–O in different bending vibration bands at 535 cm-1 and 1122 cm-1, as well as stretching vibration of Cu–O at 1640 cm-1. From UV–visible spectroscopic measurements, the energy band gap of greenly synthesized CuO NPs was found to be 1.73 eV. The SEM result shows that the nanoparticles' surfaces are rough, with some of the particles having spherically random orientation. The photodegradation efficiency of green synthesized CuO NPs photocatalyst was found to be 98.35% for Congo red at optimum experimental parameters (initial concentration, 25 mg/L; exposure time, 120 min; catalyst dose, 0.2 g; and pH, 5) and 95.4% for Alizarin Red S at optimum experimental parameters (catalyst dose, 0.25 g; initial concentration, 40 mg/L; exposure time, 120 min; and pH, 4.6). The COD values determined for the degraded product strongly support the complete mineralization of the dyes toward nontoxic materials. Reusability of the catalyst was investigated for five cycles, and the results clearly indicate the green synthesized CuO NPs are highly stable, can be used for several times, and are cost-effective as well. The degradation of Congo red and Alizarin red S on the surface of the CuO NPs follows the MBG kinetic model.

It was demonstrated that the mechanism of the inner filter effect (IFE) can emerge well in the resonance Rayleigh scattering (RRS) technique and be utilized as a new analytical method in the design of innovative IFE-based sensors. To prove this process, silver nanocubes (Ag NCs) with tunable extinction spectra were selected as RRS probes, and three analytes, doxorubicin (DOX), sunitinib (SUN), and Alizarin Red S (ARS), were considered as the typical absorbers. In addition, in the presence of SUN as a typical analyte, the quenching of the RRS signal of Ag NCs, with λmax of 419 nm, was linear in the range 0.01 to 2.5 µM of SUN. The limit of detection (LOD) was 0.0025 µM. The introduced method was then used to develop a dual-signal assay for the ratiometric determination of Al3+ ions. The suggested dual-signal assay was based on the color changes of ARS caused by Al3+ and the IFE between ARS and Ag NCs. The obtained results showed that the two characteristics of response sensitivity and linear dynamic range are very satisfactory for sensing Al3+ ions. The findings of this study demonstrate that the newly developed IFE mechanism can be employed as an attractive and highly efficient analytical technique for measuring different analytes. [ABSTRACT FROM AUTHOR]

Marking technology is essential to evaluate the growth performance of shellfish species in aquaculture. Some fluorochromes have been widely used in shellfish growth studies, but their marking quality remains unresolved. In order to establish an effective marking technology in bivalves, three fluorochromes are used to evaluate the suitability of in situ growth markers in spats of commercially important bivalve, Manila clam Ruditapes philippinarum. Three different concentrations of calcein (CAL; 25 mg/L, 50 mg/L and 100 mg/L), alizarin red S (ARS; 5 mg/L, 10 mg/L and 20 mg/L) and oxytetracycline hydrochloride (OTC; 250 mg/L, 500 mg/L and 750 mg/L) were used to examine their potential effects on marker quality, growth and survival of spats. In general, marking quality scores for the three fluorochromes have a positive correlation with their increased concentrations. CAL (50–100 mg/L) and ARS (10–20 mg/L) have produced healthy spats with a bright and clear fluorescent shell mark after the recovery culture for 69 days. In contrast, OTC appears to have the weak staining signals at all concentrations. The growth and survival rates affected by fluorochrome immersion are negligible at all concentrations. The present findings indicate that in situ CAL and ARS marking of spats with moderate concentrations are non-invasive and effective method for growth studies in clams. The suitability of CAL and ARS as in situ growth markers in clams will provide new marking techniques to distinguish cohorts or families in aquaculture.

The potential of the raw cuttlebone nano-powder (CBNP), a biomass waste, as a novel and nontoxic adsorbent for the adsorption of Alizarin Red S (ARS) from water solutions was investigated. To achieve the highest efficiency for the removal of ARS, some affecting factors were optimized. Common techniques (FTIR, FESEM, EDX and XRF) were used to characterize the physicochemical features of the adsorbent. Various kinetic and isotherm models were used to obtain the useful information about the adsorption mechanism of the dye onto the adsorbent. The maximum dye removal efficiency was obtained with the adsorbent amount of 500 mg (in 50 mL) and initial pH of 2 in 10 min for 20 mg/L ARS solution. Under these optimum conditions the complete removal of ARS was obtained while the maximum adsorption capacity was 38.51 mg/g. The well fitness of pseudo-second order kinetic model in the adsorption process was proved by kinetic studies. According to the obtained results, Freundlich isotherm model can suitably describe the adsorption of ARS on the sorbent. The achieved results from this study showed the excellent capability of CBNP for the adsorption of ARS.

The increasing water pollution day by day has increased the importance of developing new adsorbent materials. In this study, composite hydrogel containing gelatin, [2-(Acryloyloxy)ethyl] trimethylammonium chloride (AETAC) and Graphene Nanoplate (GNPt) was developed as an adsorbent for the removal of dyes from wastewater. Fourier Transform Infrared Spectrophotometer, Scanning Electron Microscope, X-Ray Diffractometer results confirmed the crosslinked polymer structure of Gelatin/p(AETAC)/GNPt composite hydrogel (Gel 5). In addition, equilibrium swelling ratio, which is a parameter affecting the adsorption behavior, was 48.22 gwater /ggel. The adsorption behavior of Alizarin Red S anionic dyestuff on composite hydrogel from aqueous solutions was investigated under various experimental conditions such as initial dye concentration of solution, amount of adsorbent, contact time, pH of solution, temperature of solution. ARS dye adsorption on composite hydrogel is consistent with Pseudo-Second-Order kinetic model and Langmuir isotherm with max adsorption capacity of 649.35 mg/g. The composite hydrogel with high mechanical strength has high dye removal ability in the ranging pH from 4 to 8. Therefore, it can be said that Gelatin/p(AETAC)/GNPt composite hydrogel has a substantial potential for the removal of anionic dyes from wastewater in a wide pH range. [ABSTRACT FROM AUTHOR]

This work presents an effective and highly sensitive electrochemical detection of Sunset Yellow (SSY) at poly(Alizarin Red‐S) and functionalized multi‐walled carbon nanotubes composite modified glassy carbon electrode (f‐MWCNTs/poly(ALR‐S)/GCE). The electrochemical response of the f‐MWCNTs/poly(ALR‐S)/GCE towards SSY was examined by cyclic voltammetry (CV) and square wave voltammetry (SWV). Both recorded cyclic voltammograms (CVs) and square wave voltammograms (SWVs) showed that the oxidation/reduction peaks of SSY at f‐MWCNTs/poly(ALR‐S)/GCE were found to be much higher than the bare GCE, f‐MWCNTs/GCE, and poly(ALR‐S)/GCE. Calibration curves obtained from the SWVs indicated that the f‐MWCNTs/poly(ALR‐S)/GCE offers a linear response in the range of 0.50 to 256 μM with a low detection limit (LOD) of 0.16 μM and the sensitivity was found to be 9686 μA mM−1 cm−2. The f‐MWCNTs/poly(ALR‐S)/GCE provides excellent performance for the detection of SSY in daily life samples with high accuracy and precision. [ABSTRACT FROM AUTHOR]

The present research reports the adsorption capacity of magnetic NiFe-layered double oxide (NiFe-LDO) derived from the heat treatment of NiFe-layered double hydroxide (NiFe-LDH) on capturing of single anionic dye and mixed dyes in water. The formation and characteristics of NiFe-LDH and NiFe-LDO were verified by XRD, FT-IR, SEM, BET, VSM and UV-VIS. The obtained NiFe-LDO was mainly composed of NiFe2O4 and NiO phases, which showed strong magnetic property and made the adsorbents easily collected by external magnet. The amounts of the anionic dyes were captured on NiFe-LDO surface more than that on NiFe-LDH surface due to the larger surface area (68 m2/g for NiFe-LDO and 50 m2/g for NiFe-LDH). The maximum adsorption capacity of NiFe-LDO was in the range of 256–313 mg/g and 244–300 mg/g for eliminating the anionic dyes in single and multiple dye solution, respectively. The chemical adsorption affinity of the anionic dyes on the positive-charge surface of NiFe-LDO increased as follows: methyl orange

This study depicts the plan, optimization, validation, and utilization of a novel polyvinylchloride (PVC) lattice-assisted membrane sensor to quantify fexofenadine hydrochloride (FFH) by utilizing Alizarin Red S (ARS), β-cyclodextrin (β-CD) and nitrophenyl octyl ether (NPOE) as an ion-exchanger, ionophore, and plasticizer respectively. The PVC network-assisted FFH-ARS sensor answers in <15s with super Nernstian conduct for FFH over 2.5x10-6-1.25x10-3 mol L-1 in the pH of 2.0 to 5.5 range. The regression coefficient acquired for the alignment plot is 0.9921. The determined Nernstian slope of the line is 56.18±1.25 mV/decade. The detection limit (LOD) is viewed as 3.5x10-7 mol L-1. Validation results clarified its appropriateness to assay FFH precisely and definitively. The sensor is a decent one for robust and rugged capability with a mean RSD of 4.39%. The outcomes of the interference study confirmed the non-interference of foreign ions while measuring the potentials. Statistical comparison of the outcomes confirms the good agreement of results of the proposed analytical procedure with the reference one. The percentage of mean recovery of FFH utilizing the proposed FFH-ARS sensor was 98.56 and 95.61% for the tablets and spiked human urine respectively, and this affirmed the selectivity of the solid-state electrode for FFH. [ABSTRACT FROM AUTHOR]

Two fluorescent dyes, alizarin red S (ARS) and calcein (CAL), were applied to evaluate the marking effects on the juveniles of Acanthopagrus schlegelii. The total mortality rates of the experimental groups were significantly lower (p < 0.05) than those of control groups, but no significant difference was detected between those of the two staining methods. The fluorescence microscopy observation results showed that the marking quality of ARS was better than that of CAL, with fin spines and fin rays being the best marking tissues. The optimal concentration for ARS and CAL was 200 mg/L and 350 mg/L, respectively. To ensure mark quality, the recommended dye grade was above 3, and the most suitable marking conditions were suggested to be fluorescence labeling with ARS dye at a concentration of 200 mg/L, with immersion for 24 h. The results will provide useful data information for future research on stock enhancement using the chemical marking method. [ABSTRACT FROM AUTHOR]

Observing mineralization is essential for studying skeletal development, maintenance, and regeneration. Calcein and alizarin red have long been used to visualize mineralization in fixed specimens, but this requires the target animals to be sacrificed. However, several intravital bone‐staining methods have been developed to visualize mineralized tissues in living animals. These methods have been applied to study fin rays and transparent fishes. Xenopus tropicalis is an excellent experimental animal model for studying bone formation and regeneration because skeletal mineralization begins during the free‐living tadpole period, and its regenerative ability changes during metamorphosis. However, intravital bone staining of X. tropicalis has only been reported for tadpoles, and no details on its specificity or appropriate experimental conditions are available. Here, we compared the calcein‐ and alizarin red S (ARS)‐staining methods and optimized these methods for tadpoles and juvenile frogs during and after metamorphosis. Staining with 0.01% ARS yielded acceptable signaling for young tadpoles, whereas calcein either at 0.1 or 0.01% occasionally showed artifactual staining of unmineralized tissues. In addition, 0.1% calcein or 0.1% ARS staining showed a higher signal‐to‐noise ratio with juvenile frogs compared to staining at 0.01%. We propose the use of 0.01% ARS for tadpoles before stage 61 and 0.1% ARS thereafter for staining mineralized tissues. Using this method, we found that ossification of the neural arches occurred at stage 51 in X. tropicalis. This method enables precise staging and manipulation based on the visualized bone structure. [ABSTRACT FROM AUTHOR]

Synthetic dyes, such as Alizarin Red S, contribute significantly to environmental pollution. This study investigates the biosorption potential of Alhagi maurorum biosorbent for the removal of Alizarin Red S (ARS) from aqueous solutions. Fourier transform infrared spectroscopy (FTIR) was used to analyze the biosorbent's adsorption sites. Various parameters were optimized to maximize dye adsorption. An optimal removal efficiency of 82.26% was attained by employing 0.9 g of biosorbent with a 25 ppm dye concentration at pH 6 and 60 °C over 30 min. The data were modeled using various isothermal and kinetic models to understand the adsorption behavior. Thermodynamic parameters indicated that the adsorption process was spontaneous and endothermic. The pseudo-second-order kinetic model best described the data, indicating chemisorption as the rate-limiting step. The data matched best to the Langmuir model, indicating that the adsorption occurs as a monolayer on uniform surfaces with a finite number of binding sites. The model showed a strong correlation (R² = 0.991) and a maximum adsorption capacity (q max ) of 8.203 mg/g. Principal component analysis (PCA) identified temperature as the dominant factor, with the primary component, PC1 capturing 100% of its effect. The mechanisms involved in ARS biosorption on A. maurorum include electrostatic interactions, hydrogen bonding, hydrophobic interactions, dipole-dipole interactions, and π-π stacking. Alhagi maurorum showed promising potential for biosorbing toxic dyes from contaminated water, suggesting further investigation for practical applications., (© 2024. The Author(s).)

Exploration of innovative strategies aiming to boost energy densities of supercapacitors without sacrificing the power density and long-term stability is of great importance. Herein, highly porous nitrogen-doped carbon spheres (NPCS) are decorated onto the graphite sheets (GSs) through a hydrothermal route, followed by a chemical activation. The capacitive performance of the NPCS is then enhanced by hydroquinone sulfonic acid (HSQA) incorporation in both cathodic electrolyte and electrode materials. Later, NPCS are decorated with polypyrrole (PPY), in which HSQA takes a versatile role as conjugated polymer dopant and cathodic redox additive. The capacitive performance of the negative electrodes is enhanced by incorporating of alizarin red S (ARS) as anodic redox additive. Finally, PPY(HQSA)@NPCS-GS//NPCS-GS asymmetric supercapacitor is assembled and tested in dual redox electrolyte system containing HQSA-cathodic and ARS-anodic electrolytes. This device delivers a remarkable energy density of 60.37 Wh kg -1 , which is close or even better than lead acid batteries. Thus, the present work provides a novel pathway to develop high energy supercapacitors using redox active electrolytes for next-generation energy storage applications., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

Alizarin red S is a sulfonated, water-soluble derivative of alizarin. This work presents femtosecond studies of alizarin red S (ARS) nanoparticles in comparison to ARS in aqueous solution and to alizarin in DMSO. The femtosecond studies cover a probing spectral range of 350–750 nm using different excitation wavelengths, taking into account the variation of the absorption spectra with the pH values of the solvent. Stationary absorption spectra show slight differences between solution and nanoparticles. Excitation at 530 nm results in low and noisy responses, therefore, we additionally recorded transient spectra of the nanoparticles at λex = 267 nm. While the results in DMSO are comparable to previous studies in non-aqueous solvents, we report a relatively fast relaxation of 14 ps in [La(OH)2][ARS] nanoparticles in aqueous solution after excitation at 530 nm, which is similar to Na(ARS) solution (19 ps). The dynamics changed with lower pH, but still without significant differences between nanoparticles and solution. We propose [La(OH)2][ARS] nanoparticles as a suitable alternative to dissolved molecules with similar spectroscopic properties, for example, with regard to biomarker applications.

Textile dyes are becoming a growing threat to the environment. This report presents the findings of the study on the toxicity of the textile dye Alizarin Red S on two freshwater microalgae. The acute toxicity assay revealed that 96-h EC50 values of Chlorella vulgaris and Spirulina platensis were 29.81 mg/L and 18.94 mg/L respectively. The pigments chlorophyll-a, b and carotenoids in C. vulgaris on 96-h exposure to the dye were 2.91, 3.29 and 3.01 times lower in analogy to control whereas Spirulina platensis showed 2.89and 2.56 fold decrease in chlorophyll-a and carotenoid content than control. After the test period of 96-h with dye, the protein content of C. vulgaris and S. platensis were 2.33 and 1.77 times lower compared to the control. The growth inhibition rate, pigment as well as the protein content declined in compliance with the rise in dye concentration, which anticipate paradigm about the toxic effects of the textile dye. Highlights: Inhibition of growth rate and changes in the biochemical composition reveals the toxicity of the textile dye. ARS can be considered as harmful to the aquatic organism according to the EU-Directive 93/67/EEC. Dye toxicity to microalgae varies depending on the dose and exposure period. [ABSTRACT FROM AUTHOR]

In the field of stimuli-responsive materials, introducing a pH-sensitive dyestuff onto textile fabrics is a promising approach for the development of wearable sensors. In this paper, the alizarin red S dyestuff bonded with a sol-gel precursor, namely trimethoxy-[3-(oxiran-2-ylmethoxy)propyl]silane, was used to functionalize polyethylene terephthalate fabrics, a semi-crystalline thermoplastic polyester largely used in the healthcare sector mainly due to its advantages, including mechanical strength, biocompatibility and resistance against abrasion and chemicals. The obtained hybrid halochromic silane-based coating on polyester fabrics was investigated with several chemical characterization techniques. Fourier transform infrared spectroscopy and X-ray Photoelectron Spectroscopy confirmed the immobilization of the dyestuff-based silane matrix onto polyethylene terephthalate samples through self-condensation of hydrolyzed silanols under the curing process. The reversibility and repeatability of pH-sensing properties of treated polyester fabrics in the pH range 2.0–8.0 were confirmed with diffuse reflectance and CIELAB color space characterizations. Polyester fabric functionalized with halochromic silane-based coating shows the durability of halochromic properties conversely to fabric treated with plain alizarin red S, thus highlighting the potentiality of the sol-gel approach in developing durable halochromic coating on synthetic substrates. The developed wearable pH-meter device could find applications as a non-invasive pH sensor for wellness and healthcare fields. [ABSTRACT FROM AUTHOR]

[Display omitted] The broad detection properties of alizarin, not only concerning pH variations but also temperature, glucose and health-like relevant cations alterations, make it a molecule of great scientific interest, particularly for developing multifunctional wearable sensors. Herein, the alizarin red S dyestuff is bonded with trimethoxy-[3-(oxiran-2-ylmethoxy)propyl]silane, as a sol–gel precursor, to functionalize cotton fabrics. The chemical and structural properties of both plain and silane-functionalized dyestuffs are investigated in solution and solid-state by several chemical-physical characterization techniques. The hybrid dyestuff characterization reveals the epoxy ring-opening of the silica precursor, leading to covalent linkages to the sulfonic group of alizarin, which retains its structure during the sol–gel reaction. The silane-functionalized halochromic dyestuff shows similar halochromic behaviour as its pristine solution in the investigated pH range, thus demonstrating a color shift from yellow to red due to the protonation/deprotonation reversible mechanism of the chromophore. The reversibility and repeatability of pH-sensing properties of treated cotton fabrics are confirmed by diffuse reflectance and CIELAB color space characterizations. Cotton fabric functionalized with alizarin-containing sol–gel coating shows excellent durability of halochromic properties, thus emerging as a versatile platform for stimuli-responsive materials. [ABSTRACT FROM AUTHOR]

In order to understand the chelation process and investigate the intermediate species as a step towards verifying the exact functional groups that are involved in bonding with transition metals, specifically Cu(II) and Zn(II), pH-oscillotitrimetric (pHOT) and volumetric-oscillographic (VOG) methods have been profoundly used. Alizarin Red S (ARS) - as one of the chameleon compounds (chromogenic) - confirms its different approach of bonding with copper and zinc in different mediums. These two methods thoroughly confirm the adequate conditions for each metal to chelate with ARS. pH is responsible for the ambience in which the formation energy in its less value for the salt or complex to be formed, confirming that pH = 5 is the value that allows Cu(II) to bond with ARS, whereas Zn(II) bonds at pH = 6. A new approach has been also suggested as to how to discuss the titrimetric curves in both methods, taking into account the importance of ‘volumetric-oscillographs’ that give more information when analysed appropriately. Volumetric-oscillographs have been shown and utilized as fingerprint spectrums to track any change in the solutions and firmly expect the compounds that can be step-by-step formed during titration operation. The resulting-in rules have been suggested during reading the graphs. Moreover, the competition between these two metals to chelate with ARS has been extensively studied.

One-pot, facile and green synthesis of zinc oxide nanoparticles are synthesized using cow dung as fuel by combustion procedure. The synthesized material is characterized by using various techniques such as XRD, FTIR, UV, FESEM, and EDX. To assess the photocatalytic efficacy of the as-synthesized material, harmful cationic and anionic dyes such as methylene blue (MB) and alizarin red S (AZ) dyes, respectively, are selected as benchmark dyes. The influence of light source, dye concentration, photocatalyst dosage, and pH value on the efficiency of photocatalyst and kinetics of photodegradation are systematically studied. The photodegradation results revealed that the synthesized ZnO NPs exhibited removal efficiency of MB and AZ dyes upon irradiation with UV light. Concisely, the removal efficacy of the ZnO NPs under UV light irradiation exhibited an MB and AZ degradation of 99.9% and 96.8%, respectively. A reasonable photo-catalytic mechanism for the high photodegradation efficacy of MB and AZ dyes by the prepared photocatalyst is also proposed. The green fabricated photocatalyst is promising material and could be applied for waste-water remediation and other ecological applications.

Fungi were used as one of the most common bioremediation methods. From this perspective, our study highlights the optimization of Alizarin Red S (ARS) dye adsorption performance for the sodium alginate (SA) by using the fungus Aspergillus terreus (A. terreus) to form a composite bead and the possibility of its reusability. This was accomplished by mixing SA with different ratios of biomass powder of A. terreus, including 0%, 10%, 20%, 30%, and 40%, to form composite beads of A. terreus/SA-0%, A. terreus/SA-10%, A. terreus/SA-20%, A. terreus/SA-30%, and A. terreus/SA-40%, respectively. The ARS adsorption characteristics of these composite mixtures were analyzed at various mass ratios, temperatures, pH values, and initial concentrations. Moreover, sophisticated techniques, such as scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR), were employed to detect the morphological and chemical properties of this composite, respectively. The experimental results revealed that A. terreus/SA-20% composite beads have the highest adsorption capacity of 188 mg/g. Its optimum adsorption conditions were achieved at 45 ∘C and pH 3. Moreover, the ARS adsorption was well explained by the Langmuir isotherm (qm = 192.30 mg/g) and pseudo-second-order and intra-particle diffusion kinetics. The SEM and FTIR findings corroborated the superior uptake of A. terreus/SA-20% composite beads. Lastly, the A. terreus/SA-20% composite beads can be employed as an eco-friendly and sustainable alternative to other common adsorbents for ARS.

In this work, the adsorption of Cr(VI) ions and the organic dye Alizarin Red S (ARS) was investigated using magnetite talc (Fe3O4@Talc) nanocomposite. Different characterization techniques such as scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), and thermogravimetric analysis (TGA) were used to demonstrate the physical and chemical properties of the fabricated Fe3O4@Talc nanocomposite. In addition, the adsorption isothermic, kinetic, and thermodynamic properties were illustrated. The results demonstrate that the investigated adsorption processes obeyed the Langmuir isotherm model for Cr(VI) and the Freundlich isotherm model for ARS dye, with a maximum adsorption capacity of 13.5 and 11.76 mg·g−1, respectively, controlled by pseudo second-order kinetics. Regeneration and reusability studies demonstrated that the prepared Fe3O4@Talc nanocomposite is a promising and stable adsorbent with considerable reusability potential. [ABSTRACT FROM AUTHOR]