Dye Phenol Research Articles

Peculiarities of solvatochromism of 4-[[(2,4-dinitrophenyl)methylene]imino-2,6-diphenyl]phenol and Reichardt’s dye. DFT calculations

One of the current directions of development of modern physical chemistry is the working out of sensor devices and molecular probes for the study of various properties of solutions, colloidal systems and biological objects. The latter include solvatochromic dyes, which, thanks to Reichardt's classic works, have found wide application for quantitative assessment of the solvating ability of individual and, to a lesser extent, mixed solvents of various nature. The different behavior of Reichardt and 4-[[(2,4-dinitrophenyl)methylene]imino-2,6-diphenyl]phenol dyes in pure water and mixed water-organic solvents, when their composition is changed, indicates that their electronic structure undergoes a fundamental change during the transition from the ground state to the first excited state. The aim of the work was to study and compare the HOMO and LUMO structure of the standard Reichardt betaine dye and the 4-[[(2,4-dinitrophenyl)methylene]imino-2,6-diphenyl]phenol dye using the stationary and time-dependent density functional theory (DFT). It is proved that the 4-[[(2,4-dinitrophenyl)methylene]imino-2,6-diphenyl]phenol dye has two active exchangeable solvation centers and therefore has an excellent solvation mechanism, at least in aqueous solution, compared to Reichardt dye, which should appear upon its solvation also in mixed water-organic solvents with a high water content in them.

An efficient and unique method for the growth of spindle shaped Mg-doped cerium oxide nanorods for photodegradation of p-Nitrophenol

Photocatalytic degradation of phenolic dyes has always been a challenge in front of the research community. Therefore, to resolve the problem, present work aims to synthesize the unique cerium oxide nanorods using modified solvothermal method. These nanorods are combined in such a manner that they form spindle-shaped morphology. X-ray diffraction (XRD) and transmission electron microscopy (TEM) measurements confirmed the formation of spindle-shaped cerium oxide nanorods. Raman and X-ray photoelectron spectroscopy (XPS) are employed to explore the electronic properties, and lattice defects. The unique morphology and lattice defects are responsible for effective p-Nitrophenol (PNP) degradation up to 90.2 % in 5 h using 6 % Mg doped CeO2 photocatalyst in the presence of UV light. The oxygen vacancies in the form of lattice defects increased the magnetization in Mg doped CeO2 that have been explained based on F-center exchange (FCE) mechanism. Hence, Mg doped cerium oxide has been proven as a bi-functional material for spintronics and photocatalysis.

The Effects of Lanthanide Ions Doping and Chromophore Anchoring on the Photocurrent Response and Photocatalytic Behaviours of Titanium‐Oxo‐Clusters

AbstractLanthanide‐titanium‐oxo‐clusters (LnTOCs) have been attractive as a rapidly growing class of molecular materials due to their use as molecular models and precursors of nano titanium oxide. Although various applications of LnTOCs with alkoxide/carboxylate ligands have been documented, phenol dyes coordination LnTOCs applications in antibiotics fields have not been reported yet. Herein three LnTOCs formulated as [Ti2Ln2O(OiPr)6(NO3)4(2,3‐DN)2]2 ⋅ 3.5Et3N ⋅ 2HOiPr (Ln=Tb (1), Eu (2) and Yb (3)) were designed and synthesized. Their structures consisted of a Ti2Tb2O subunit and two 2, 3‐DN ligands. Using cluster 1, Ti2(2, 3‐DN)2 and Ti2Tb2, photocurrent response and photocatalytic dye degeneration were examined. The improvements in photocurrent intensity and photocatalytic activity of dye‐degradation could be attributed to the cooperative effect of the Ln3+ doping and 2, 3‐DN coordination. Furthermore, using cluster 1 as a precursor, F1 exhibited high photoactivity for tetracycline. The antibiotics application of LnTOCs was evaluated firstly. The results indicate that clusters 1–3 have potential applications as a molecule based photodegeneration catalyst.

Immobilization of Laccase on Hybrid Super-Structured Nanomaterials for the Decolorization of Phenolic Dyes

In the present work, hybrid super-structured nanomaterials were synthesized by the combination of smectite nanoclays with various carbon-based nanomaterials (graphene oxide, carbon nanotubes and adamantylamine) and were used as nanosupports for the covalent and non-covalent immobilization of laccase from Trametes versicolor (TvL). TvL was successfully immobilized on these hybrid nanomaterials, achieving high immobilization yields (up to 85%), while its conformation remained unaltered upon immobilization. The apparent kinetic constants Vmax and Km of the immobilized enzymes strongly depended on the immobilization procedure and the composition of hybrid nanomaterials. Immobilized TvL preserved up to 50% of its initial activity after 24 h of incubation at 60 °C, while free enzyme was totally deactivated. The TvL-hybrid nanomaterials bioconjugates were efficiently applied for the degradation of various synthetic dyes, exhibiting excellent decolorization capacity, as well as high reusability (up to 11 successive catalytic cycles), providing insights into the use of these bionanoconjugates on applications with environmental, and industrial interest.

اصطناع بوليميرات آزو ببلمرة مشتاقات إيتيرية لبروميد الآليل ودراسة فجوتها الطاقية وتعيين بعض خصائصها الفيزيائية

في هذا البحث، اُصطنع مشتقان ايتريين لاصبغة ازو فينولية عن طريق تفاعل ويليمسون وفقاً لآلية. الاستبدال النيكلوفيلي SN2. تمت بلمرة المركبات المحضرة بلمرةً جذرية باستخدام (AIBN) كبادئ وأُثبتت بنى المركبات المصطنعة بواسطة مطيافيات FT-IR و 1H-NMR. بالإضافة إلى دراسة الخصائص الحرارية للبوليميرات المُحضرة بواسطة (DSC). دُرست عرض الفجوة الطاقية وذلك لمعرفة امكانية استعمال البوليميرات كأنصاف نواقل ضوئية وكانت قيمتها 2.4ev, 2.8ev لكل من P(AO2) و P(AON1) على التوالي. كماعُينت كل من قرينة الانكسار واللزوجة الكيناميكية والكثافة ودرجة العكارة.

Effect of Ag doped MnO2 nanostructures suitable for wastewater treatment and other environmental pollutant applications

A modest sol-gel method has been employed to prepare the pure and Ag doped MnO2 nanoparticles and methodologically studied their physical, morphological, and photosensitive properties through XRD, TEM, EDAX, Raman, UV, PL and N2 adsorption - desorption study. Tetragonal crystalline arrangement with spherical nanoparticles was found out through XRD and TEM studies. The EDAX studies further supported that formation Ag in the MnO2 crystal matrix. The bandgap energy of Ag doped MnO2 was absorbed through UV spectra. Photo -generated recombination process and surface related defects were further recognized by PL spectra. Through visible light irradiation, the photo - degradation of methyl orange (MO) and phenol dye solutions were observed. The optimum condition of (10 wt% of Ag) Ag doped MnO2 catalyst showed tremendous photocatalytic efficiency towards MO than phenol under same experimental study.

A ratiometric fluorescent probe for sensing hypochlorite in physiological saline, bovine serum albumin and fetal bovine/calf serum

HClO/ClO-, as one of important reactive oxygen species, is a highly reactive unavoidable by-product generated from normal cell metabolism. In recent years, efficient method for detectiing HClO/ClO- is of great important to research its pathological or physiological function in bio-systems. In this work, we have constructed a fluorescent probe (P-Hc) with ratiometric signal for sensing HClO/ClO- in aqueous solution, physiological saline and different serums based on 2-(benzo[d]thiazol-2-yl)phenol dye. The structure of P-Hc was characterized by NMR and HRMS spectrum. The sensing mechanism has also been verified by 1H NMR spectrum. The P-Hc displays good sensitivity and selectivity for HClO/ClO- with a limit of detection (LOD) of 2.03 × 10-6 M. Furthermore, P-Hc has been applied for sensing HClO/ClO- in physiological saline and different serums. Thus, P-Hc may provide a novel method for ratiometric fluorescent sensing HClO/ClO- in bio-samples.

Determination of 40 dyes in oxidative hair dye products by high performance liquid chromatography

氧化型染发产品中的多种染发剂具有不同程度的致敏性及其他毒性,建立快速、准确检测多种染发剂的方法,为该类产品监管提供有效的技术手段,十分必要。该研究建立了氧化型染发类产品中40种染发剂的高效液相色谱测定方法。染发产品经含70%乙醇的亚硫酸氢钠水溶液涡旋、超声提取,并经亚硫酸氢钠水溶液稀释后,以0.02 mol/L乙酸铵水溶液(含4%乙腈)和乙腈为流动相,采用Waters Atlantis® T3 MV Kit色谱柱(250 mm×4.6 mm, 5 μm)分离,配合柱温变化进行梯度洗脱,二极管阵列检测器检测,检测波长为235 nm和280 nm,外标法定量。结果表明,40种染发剂在各自范围内线性关系良好,相关系数均大于0.999; 40种染发剂的检出限为5~168 μg/g,定量限为16~504 μg/g;各染发剂在3个添加水平下的平均回收率为81.4%~109.6%, RSD均小于5%;各染发剂标准溶液在24 h内稳定性良好,RSD为0.2%~2.2%。与现行标准检验方法相比,该方法较大程度地增加了单一液相色谱条件下可测定的染发剂,特别是准用染发剂种类(36种),提高了检测效率,并可保证检测结果的灵敏度与准确性,适用于氧化型染发产品中多种染发剂的检测分析。

Ex situ Coloration of Laccase-Entrapped Bacterial Cellulose with Natural Phenolic Dyes

This study aimed to ex situ colorize laccase-entrapped bacterial cellulose (BC) with natural phenolic dyes, namely,madder, turmeric, and cochineal, and to determine the effect of laccase entrapment on the dyeability of BC using color strength (K/S) analysis. Results showed that laccase entrapment improved the dyeability of BC and that pre-entrapment was the most effective method, compared with meta-entrapment and post-entrapment methods. In addition, surface characterizations confirmed the successful entrapment of laccase inside the BC nanostructure and retention of the cellulosic and crystalline structures of BC. The washing durability test confirmed that the K/S value of BC had improved after laccase entrapment. Furthermore, laccase-entrapped BC colorized with cochineal dye had the highest washing durability due to the high molecular weight of cochineal dyerelative to the other dyes. This study suggests a novel method for enhancing the dyeability and washing durability of BC colorized ex situ with natural phenolic dyes by laccase entrapment.

Surface photosensitization of ZnO by ZnS to enhance the photodegradation efficiency for organic pollutants

It is challenging to develop a material which has low cost, high activity, good stability and recyclability under light exposure. Apart from these properties, the photocatalyst should also have good visible region absorbance and low electron-hole pair recombination rate. Keeping all this in view, we have designed a simple scalable synthesis of ZnO–ZnS heterostructures for the photocatalytic treatment of industrial waste (p-nitrophenol and methyl orange). The ZnO–ZnS heterostructures are synthesized via a solvent-free route by thermal annealing of solid-state mixture of ZnO and thiourea (a sulphur source) which results in ZnO–ZnS core shell kind of heterostructure formation. The interface formation between the ZnO–ZnS heterostructure favored the band-gap reduction in comparison to the bare ZnO and ZnS nanoparticles. Further, these ZnO–ZnS heterostructures were utilized as a photocatalyst for the degradation of toxic phenolic molecules (p-nitrophenol) and harmful organic dyes (methyl orange) present in the water under the light exposure (> 390 nm).

Removal of Phenol Dye by CoFe 2 O 4 -CdFe 2 O 4 Nanocomposites

This work includes the study of adsorption of phenol red dye by using spinel Co1- xCdxFe2O4 was prepare by Co-precipitation method at different ratios of (0.2:0.8, 0.5:0.5, 0.8:0.2) and calcinations at temperature 600 0C for three hours. The conclusion showed that (0.5:0.5) percentage has high activity than other ratio at different temperature. The prepared powder was differentiated by X-ray diffraction, Fourier Transform Technique (FT-IR), UV-Visible Spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Atomic Force Microscope (AFM), high performance liquid chromatography (HPLC).

Synthesis and Investigation of Template Effects on Nanoporous Bi2O3 Morphologies by Sol Gel Method as Photocatalysts for Degradation of Some Organic Dyes as Water Pollutants

Effect of triethanolamine, n-octylamine, starch, polyethylene glycol and hexadecyltrimethylammonium bromide as template have been investigated on the formation of Bi2O3 prepared via sol gel method. The prepared catalysts were characterized using X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared, UV–visible diffuse reflectance and Brunauer–Emmett–Teller techniques and subsequently used as photodegradation catalyst to purify contaminated water by Congo red and methylene blue as phenolic dyes. It was found that whereas Bi2O3-starch, Bi2O3-CTAB and Bi2O3-PEG have the most photodegradation effect on methylene blue under visible irradiation, Bi2O3-starch and Bi2O3-CTAB are the most active catalysts for Congo red under UV irradiation. In other word, the type of organic dyes, photocatalyst morphologies and templates are important factors on the photodegradation and adsorption phenomena.

Immobilization of anthocyanin extract from red-cabbage into electrospun polyvinyl alcohol nanofibers for colorimetric selective detection of ferric ions

An effective nanofibrous metallochromic sensor mat was developed. Electrospun nanofibers were generated from a solution of polyvinyl alcohol (PVA) as a host polymer and anthocyanin extract from red-cabbage as an active detection sites. Using PVA as a supramolecular hosting matrix and anthocyanin phenolic dye (AC) as a spectroscopic probe, a novel, simple, rapid, portable and colorimetric sensor was developed for ferric ions (Fe3+) in aqueous environments. Binding these toxic ferric cations causes an appreciable color change from colorless to pink as proved by the CIE Lab color parameters. The visible color variation was found to change proportionally depending on increasing the concentration of ferric ions. The naked-eye recognition of Fe3+ was rationalized on the basis of Fe(III)-phenolic anthocyanin complex formation. High Performance Liquid Chromatography Mass Spectrometry (HPLC-MS) was applied to characterize the anthocyanin extract. The surface morphology and structural characterization of the generated nanofibers were explored by scanning electron microscopy (SEM) and energy-dispersive X-ray analyzer (EDS). The generated electrospun PVA-AC nanofibrous film displayed an average diameter of 150–250 nm. They were firstly cross-linked using the vapors of glutaraldehyde to turn them into water-insoluble nanofibers. Both selectivity and detection limit have been also studied. The anthocyanin-containing nanofibers display an excellent simplicity and reusability with a limit of detection in the range between 1 and 350 mg/L. The detection limit was monitored as low as 1 mg/L. PVA-AC showed excellent selectivity compared to other transition metal ions, including Cu2+, Mg2+, Hg2+, Co2+, Ba2+, Zn2+, Ni2+, Cr3+, Al3+, Ca2+, K+, Na+, Cd2+ and Mn2+. The best optimized conditions for the detection of Fe3+ was achieved in a pH range from 3.75 to 6.0. The proposed assay has the advantage of rapidity, simplicity, facile fabrication, low cost, environmental safety and easy to operate compared to other detection techniques.

Micellar effect of CTAB on Phenol red sodium salt: A model system may be used for cell membrane study

This communication reports the effect of micelles on the molecular organisation of an anionic fluorescent dye Phenol Red Sodium salt (PRSS) in Langmuir-Blodgett (LB) film. PRSS is a water soluble anionic fluorescent dye generally used as a pH marker for cell tissue culture. Below and Above CMC of CTAB the spectral characteristics.Of PRSS molecules changes which confirms the interactions of the PRSS molecules with micelles of the CTAB. UV–vis absorption and fluorescence spectroscopic studies confirm this. So we can modified the spectral behavior of the PRSS molecules in solution as well as in LB films which may be useful as an indicator in different biological process.

Structural, spectroscopic and electrical investigations of novel organic thin films bearing push-pull azo – Phenol dye for UV photodetection applications

In the current study, novel thin films of a phenol-based push-pull azo dye, 2-acetyl-4-(4-chloro-phenylazo) phenol (ACAP), with tunable optical and electronic properties were designed, synthesized and characterized for UV photodetection applications. The crystalline structure and morphological features of the thermally evaporated ACAP thin films are investigated. The fabricated thin films exhibit an amorphous-like structure with low-intensity crystalline regions of average crystallite size of about 29.51 nm and a smooth surface with nanostructured sheets formation. The optical transmittance, reflectance, and absorption of ACAP thin films are measured in the spectral range UV–vis-NIR. A significant high UV absorption extending from 190 nm to 385 nm is observed with semi-transparency nature in the visible region. Furthermore, a good agreement is obtained between the estimated value of the direct energy gap that is obtained experimentally (3.62 eV) and that calculated from the theoretical DFT approach (3.74 eV). The dispersion behavior is analyzed in terms of the single oscillator model and is employed to estimate the dispersion parameters. Finally, an organic/inorganic heterojunction device based on Au/ACAP/n-Si/Al for UV photodetection is successfully fabricated. The current–voltage relations of the manufactured photodetector showed significant stability and sensitivity to the incident UV illumination. The fabricated UV photodetector exhibits responsivity ~25.7 mA/W, specific detectivity ~2 × 109 Jones, efficiency ~16.74%, a fast and reproducible ON/OFF switching behavior with 480 ms and 218 ms rise and fall time, respectively.

Fibre-optic biosensor for the detection of xanthine for the evaluation of meat freshness

Xanthine is produced by guanine deaminase and xanthine oxidase from guanine and hypoxanthine, respectively. It serves as an indicator of spoilage of meat and various pathological conditions. An optical biosensor has been fabricated for the detection of xanthine by absorption transmission approach. The bioassay principle used in this study is conversion of xanthine to uric acid and H2O2 by XO. Due to the production of uric acid, pH of the reaction decreases and falls in range of 7.5 - 6. The absorptive dye phenol red has been screened to visualize the change in colour. The coimmobilization of XO and dye phenol red indicator was done with sol-gel method onto the circular plastic discs for the development of biosensor. Volume of sample required for detection has been miniaturized to 10μl. The linear range of concentration and limit of detection were 0.5μM – 150μM and 0.5 μM respectively, have been achieved for xanthine. The designed biosensor was successfully employed for the detection of xanthine in chicken meat sample. Present study leads to the development of a fast and dependable biosensor with miniaturized sample volume and also mass scale screening possible through colour visualization.

Studies of MnO2/g-C3N4 hetrostructure efficient of visible light photocatalyst for pollutants degradation by sol-gel technique

MnO2 and g-C3N4 heterostructure were constructed by simple sol-gel technique combined with annealing process were characterized different variety of techniques to understand the structural, morphological, optical and elemental composition were using XRD, TEM, Raman, UV, PL, BET and EDAX analysis. In fact, XRD and FESEM results shows that α-phase MnO2 structure were individually spherical shaped - like morphology nanostructures the average diameter 25 nm to 40 nm was observed apparently. In order to understand, the optical bandgap properties and specific surface area of MnO2/g-C3N4 nanocomposites were ranging from 2.55 eV - 2.78 eV & 67.23 - 105.21 m2/g, which is confirmed through UV–vis DRS and N2 nitrogen absorption desorption study. Therefore, the photocatalytic activity of the photocatalysts were estimated by degradation effect of methyl orange (MO) and toxic phenol pollutants. Among the results reveal that the MnO2/g-C3N4 hybrid catalyst have showed to owing the degradation effect 98% and high stability (only loss 3.5%) towards phenol dye concentration. This can be attributed to the separation of photogenerated electron-hole (e−/h+) pairs, overwhelms the recombination of free charges were reported in detail.

Role of cerium (Ce) dopant on structural, optical and photocatalytic properties of MgO nanoparticles by wet chemical route

Ce doped MgO nanoparticles with various doping concentrations of cerium ion were prepared by the sol–gel method. Both pure and Ce doped MgO nanoparticles were characterized by powder X-ray diffraction (XRD), Scanning electron microscope (SEM), Field emission scanning electron microscope, Energy-dispersive X-ray spectroscopy, UV–Vis diffuse reflectance spectroscopy, and Photoluminescence spectra analysis. XRD and SEM results suggest that both pristine and Ce doped MgO nanoparticles were in face centered cubic structure with individual spherical shaped nanoparticles with average particles sizes in the range of 20–30 nm. The band gap energy of pure MgO was significantly reduced from 3.81 eV to 3.22 eV. The Ce doped MgO catalyst showed outstanding photocatalytic degradation activity such as high efficiency (95%) and high stability (only loss 3.5%) towards phenol dye under visible light irradiation. The improved photocatalytic mechanism of MgO by Ce doping is also discussed.

Bioprocess optimization of laccase production through solid substrate fermentation using Perenniporia tephropora-L168 and its application in bioremediation of triaryl-methane dye.

Laccases are multi copper oxidases that can oxidize both phenolic and nonphenolic lignin related compounds. Consequently, there has been continuous demand for laccases for the oxidative degradation of phenolic dyes in effluents. In view of this, the present work was focused on laccase production by solid substrate fermentation using a newly isolated fungus Perenniporia tephropora-L168. To intensify the laccase production, the process parameters pH, nitrogen, inducer, and substrate: water ratio were optimized by using statistical model. A set of optimal conditions noted were pH 3, nitrogen 0.001 g/L; inducer 0.5% and substrate: water ratio (1:10), which yielded laccase 1,160 U/g. The crude laccase exhibited noteworthy potential to degrade a triaryl-methane dye especially Malachite green. Also, during bioremediation studies, the statistical process optimization could achieve 81% decolourization within 180 min. The laccase treatment brought chemical transformation in malachite green as evident from UV-Visible spectra, FTIR, HPLC while toxicity against bacteria and fungi was also reduced. During phytotoxicity study, effect of treated and untreated dye on germination of seed was analyzed. Interestingly, the germination index for Vigna aconitifolia and Vigna radiata was increased by two and fourfold, respectively. Overall, this work demonstrates optimized production of laccase using Perenniporia tephropora-L168 and its efficient bioremediation potential for triaryl-methane dye.

“Pillaring Effects” in Cross-Linked Cellulose Biopolymers: A Study of Structure and Properties

Modified cellulose materials (CLE-4, CLE-1, and CLE-0.5) were prepared by cross-linking with epichlorohydrin (EP), where the products display variable structure, morphology, and thermal stability. Adsorptive probes such as nitrogen gas and phenolic dyes in aqueous solution reveal that cross-linked cellulose has greater accessible surface area (SA) than native cellulose. The results also reveal that the SA of cross-linked cellulose increased with greater EP content, except for CLE-0.5. The attenuation of SA for CLE-0.5 may relate to surface grafting onto cellulose beyond the stoichiometric cellulose and EP ratio since ca. 30% of the hydroxyl groups of cellulose are accessible for cross-linking reaction due to its tertiary fibril nature. Scanning electron microscopy (SEM) results reveal the variable surface roughness and fibre domains of cellulose due to cross-linking. X-ray diffraction (XRD) and13C NMR spectroscopy indicate that cellulose adopts a one-chain triclinic unit cell structure (P1 space group) withgauche-trans(gt) andtrans-gauche(tg) conformations of the glucosyl linkages and hydroxymethyl groups. The structural characterization results reveal that cross-linking of cellulose occurs at the amorphous domains. By contrast, the crystalline domains are preserved according to similar features in the XRD, FTIR, and13C NMR spectra of cellulose and its cross-linked forms. This study contributes to an improved understanding of the role of cross-linking of native cellulose in its structure and functional properties. Cross-linked cellulose has variable surface functionality, structure, and textural properties that contribute significantly to their unique physicochemical properties over its native form.