Presence Of Resorcinol Research Articles

Clouding of Triton X-100 solutions in the presence of resorcinol or β-naphthol and their application for mercury cloud point extraction

The clouding behavior of Triton X-100 solutions was investigated in the presence of resorcinol or β-naphthol. Both agents can effectively decrease the cloud point of Triton X-100 solutions. Resorcinol is active over a wider pH range, while β-naphthol is required at concentrations 10–50 times lower than resorcinol. It was also shown that about 60–70 % of β-naphthol transfers to the micellar phase, whereas resorcinol barely enters the micellar phase (about 10–15 %). Thermodynamic parameters of the clouding process were also calculated, revealing no significant differences between thermodynamic parameters for these two substances studied. Based on the results obtained, we assume different mechanisms of phase separation by these agents. Using the systems studied, mercury cloud point extraction was successfully carried out with 8-hydroxyquinoline as a ligand. The optimal parameters for extraction were determined as follows: pH of 8 (β-naphthol) and 6 (resorcinol), ligand concentration of 0.03–0.26 mmol L−1, and surfactant concentration of 1.7 g L−1.

A novel colorimetric sensor through peroxymonosulfate activated by CoFe@CN nanozymes for on-site resorcinol detection

The presence of resorcinol (RS) in water contaminated with pollutants may engender environmental and ecosystem risks. In this study, we developed rapid and efficient colorimetric methods for the on-site quantitative determination of RS. Specifically, a synthetic nanozyme composed of nitrogen-doped carbon-coated cobalt-iron (CoFe@CN) was utilized to initiate the oxidation reaction of 3,3′,5,5′-tetramethylbenzidine (TMB) with the activator of peroxymonosulfate (PMS). Compared to the activator of hydrogen peroxide (H2O2), PMS demonstrated a sixfold enhancement in catalytic efficacy, markedly elevating the detection performance. Density Functional Theory calculations indicate that RS can serve as a reducing agent for oxTMB, confirming the theoretical feasibility of this process. A linear relationship between inhibition rate (IR %) of RS concentration and absorbance was established and the colorimetric analysis revealed a linear relationship between RS concentration and gray scale values over the range of 0–45 μM, with a detection limit of 3.39 μM. Furthermore, smartphone-based analysis of color images allows for on-site quantitative analysis of RS concentration, leveraging portability and real-time detection capabilities. This study provides pioneering analytical support for on-site water quality monitoring within the ecological environment.

Reactivity of Resorcinol on Pt(511) Single-Crystal Surface and Its Effect on the Kinetics of Underpotentially Deposited Hydrogen and Hydrogen Evolution Reaction in 0.1 M NaOH Electrolyte.

This article presents cyclic voltammetry, Tafel polarization, and ac. impedance spectroscopy examinations of resorcinol (RC) ion reactivity on Pt(511) single-crystal plane and the effect of surface-electrosorbed RC ions on the kinetics of UPD H (underpotentially deposited hydrogen) and HER (hydrogen evolution reaction) processes in 0.1 M NaOH solution. Obtained data delivered a proof for the RC ion surface adsorption and its later electroreduction over the potential range characteristic for the UPD H. A favourable role of platinum-adsorbed resorcinol anions on the kinetics of the UPD H and HER processes is also discussed. The above was explained via the recorded capacitance and charge-transfer resistance parameters (the presence of resorcinol at 1.5 × 10-3 M in 0.1 M NaOH caused significant reduction in the resistance parameter values by 3.9 and 2.6 times, correspondingly, for the UPD of H at 50 mV and the HER process, examined at -50 mV vs. RHE) along with the charge transients, produced by injecting small amounts of RC-based 0.1 M NaOH solution to initially RC-free base electrolyte on the Pt(511) electrode plane (a large cathodic charge-transient density of -90 µC cm-2 was recorded at the electrode potential of 50 mV).

Electrochemical detection and quantification of catechol based on a simple and sensitive poly(riboflavin) modified carbon nanotube paste electrode

In the present research work, selective and sensitive catechol (CT) detection and quantification were shown in the presence of resorcinol (RS) in 0.2 M phosphate buffer (PB) solution by preparing a low-cost, simple, and green carbon nanotube paste electrode (CNTPE) surface activated with electropolymerized riboflavin (PRF). The morphological, conductivity, and electrochemical features of the modified electrode (PRFMCNTPE) and bare carbon nanotube paste electrode (BCNTPE) materials were analyzed using electrochemical impedance spectroscopy (EIS), field emission scanning electron microscopy (FE-SEM), cyclic voltammetry (CV), and differential pulse voltammetry (DPV). The PRF-activated electrode displays outstanding sensitivity, stability, selectivity, reproducibility, and repeatability for the redox feature of CT with improved electrochemical current and declined electrochemical potential compared to BCNTPE. The peak currents of CT are correlated to the different CT concentrations (CV method: 6.0–60.0 μM & DPV method: 0.5–7.0 μM), and the obtained detection limit (DL) and quantification limit (QL) are found to be 0.025 μM and 0.085 μM (CV method) and 0.0039 μM and 0.0132 μM (DPV method), respectively. The prepared PRFMCNTPE material was advantageous for the examination of CT in environmentally important tap water sample as a real-time application.

Porous carbon fabricated by a residue from Longquan lignite ethanolysis as an electrochemical sensor for simultaneous detection of hydroquinone and catechol in the presence of resorcinol

Catechol (CC), resorcinol (RS), and hydroquinone (HQ) are regarded as both important raw materials widely applied in chemical industry and highly toxic organic pollutants, so accurately detecting them is very necessary. In this work, Longquan lignite residue with low added value was fabricated as highly active porous carbons (PCs). The morphology, specific surface area (SSA), and electrocatalytic oxidation performance of the PCs prepared at different activated temperatures (600 ∼ 900 °C) were studied in detail. All PCs have different portions of micropores and mesoporous, and their SSAs can reach up to 3028 m2/g. Such well-developed microporous and mesoporous structures can provide abundant active sites to facilitate ion and electron transport, and thereby improving the electrocatalytic performance. Among them, the PC prepared at 800 °C shows the best detection performance. It can successfully detect HQ and CC simultaneously in the presence of RS, with detection limits of 0.15 and 0.81 µM for HQ, 0.09 and 0.53 µM for CC comparable to some graphene-based electrochemical sensors. Additionally, the constructed electrochemical sensor also displays a good reproducibility, stability, and anti-interference, which makes it a promising candidate material for monitoring phenolic compounds in actual water samples.

Poly DY 11/Zn/CuO modified electrochemical sensor for the detection of catechol and hydroquinone: A voltammetric study

In the present work, Zn doped CuO nanoparticles (Zn/CuO Npcs) was synthesized by co-precipitation method for the fabrication of electrode towards the detection of Catechol (CA) and Hydroquinone (HY). The particle size and surface morphology of Zn/CuO Npcs was characterized by X-ray diffraction technique (XRD) and Scanning electron microscopy (SEM). Further cyclic voltammetric technique was used for the electropolymerization of Direct Yellow 11 (DY 11) on the surface of Zn doped CuO modified carbon paste electrode (MCPE) and applied for the determination of CA and HY at optimum pH 7.4. After the modification, the PolyDY11/Zn/CuO electrode exhibits very stable and sensitive current responses towards the CA and HY. The various parameters like scan rate, pH and concentration of both CA and HY were studied. Simultaneous determination of CA and HY in presence of Resorcinol (RE) was investigated by using cyclic voltammetry, Selectivity study of CA and HY was studied using the differential pulse voltametric technique. The fabricated electrode exhibits adsorption controlled and limit of detection (LOD) calculated for CA and HY in range (10–90 μM) was found to be CA(6 μM) and HY(7 μM) respectively, The real sample analysis in tap water showed better recovery between 90 and 96% for CA and 90–94% for HY respectively.

Fluorescence “turn-on” of silicon-containing nanoparticles for the determination of resorcinol

A fluorescent nanosensor based on silicon-containing nanoparticles (Si CNPs) with green fluorescence (FL) was prepared by one-step method. The prepared Si CNPs emitted green FL at 470nm under the excitation at 350nm. The FL signal of Si CNPs reveals an obvious enhancement in the presence of resorcinol (RC), due to the passivation of surface trap states of Si CNPs via the binding of OH group of RC with the NH group of Si CNPs, which allowed the formation of new radiative electron-hole recombination centers. This was confirmed by some analytical experiments performed on zeta potential, FL lifetime steady state, and the FTIR spectra. Most importantly, this nanosensor could selectively determine RC with high sensitivity and without interference from hydroquinone (HQ) and catechol (CT) as RC isomers. RC was detected in the linear range 0.05-40μM, with a detection limit of 0.012μM. The synthesized nanosensor was applied to the determination of RC in fresh fruit juice and water samples. The collected results confirmed the feasibility of our approach with high accuracy.

Electrochemical Discrimination of Dihydroxybenzene Isomer at Different Thiols Self-Assembled Monolayers on Gold and Simultaneous Determination of Catechol and Hydroquinone

The discrimination effect of dihydroxybenzene isomer including catechol (CAT), hydroquinone (HQ) and resorcinol (RE) on bare gold, and a series of thiols self-assembled monolayers (SAMs) including mercaptohexanol (MCH), 6-mercaptohexanoic acid (MHA), mercaptoethylamine (MEA), thiol-modified double-stranded DNA (ds-DNA), single-stranded DNA (ss-DNA) is first investigated by cyclic voltammetry (CV) and linear scan voltammetry (LSV). Results show that CAT, HQ and RE can not be electrochemically discriminated simultaneously by bare gold or thiols SAMs based on their oxidation or reduction peaks. Furthermore, RE has a big interference on the electrochemical response of CAT and HQ. At acidic solution (pH 4.4), in presence of RE, CAT and HQ can not be discriminated on bare gold, ds-DNA or ss-DNA SAMs. However, CAT and HQ can be discriminated well at MCH, MHA, and MEA SAMs on gold based on the difference of reduction peak potentials (ΔE pc) as 219, 212 and 165 mV respectively. MCH SAMs is chosen to study simultaneous determination of CAT and HQ due to bigger ΔE pc and current response. We fix the potential at 0.7 V for 60 s to enrich the oxidation products of CAT and HQ, then investigated the relationships of reduction peak current (i pc) with the concentrations of CAT and HQ. The i pc values are linear with the concentrations of CAT and HQ in the range of 7.0 × 10−6∼1.04 × 10−3 M. The limit of detection (LOD) is calculated to be 5.9 × 10−7 M for CAT and 8.3 × 10−7 M for HQ (S/N = 3). The MCH SAMs on gold is applied to the simultaneous determination of CAT and HQ in lake water sample and satisfactory result is obtained.

Synthesis and characterization of nanocomposite based on reduced graphene oxide-gold nanoparticles-carbon dots: electroanalytical determination of dihydroxybenzene isomers simultaneously

This work describes the synthesis, characterization, and application of a new ternary rGO-AuNPs-Cdots nanocomposite, which was extensively characterized by high-resolution electron microscopy (HR-TEM), UV-Vis spectroscopy, Raman spectroscopy, atomic force microscopy (AFM), X-ray diffraction (XRD), and electrochemical techniques. The nanocomposite was used to modify the surface of the glassy carbon electrode aiming to develop an electrochemical sensor for simultaneous determination of phenolic isomers. Electrochemical studies were performed in acetate buffer, pH 5.5. The modified rGO-AuNPs-Cdots electrode showed good electrocatalytic response for simultaneous determination of hydroquinone and catechol in the presence of resorcinol with detection limit of 1.2 × 10−8 mol L−1 and 9.6 × 10−8 mol L−1, respectively. This electrode also showed good electrocatalytic response for simultaneous determination of hydroquinone and catechol in real samples in the presence of other interferents.

Electrochemical preparation of poly (direct yellow 11) modified pencil graphite electrode sensor for catechol and hydroquinone in presence of resorcinol: A voltammetric study

Present study describes the fabrication of new electrochemical sensor by electropolymerization of direct yellow 11 on the surface of pencil graphite electrode (PGE) for the investigation of catechol (CC) and hydroquinone (HQ) in the presence of resorcinol (RS). The modified electrode surface was further characterized by Transmission electron microscopy (TEM) and Field Emission Scanning Electron Microscope (FESEM). After the modification of PGE, it exhibits an excellent electrochemical response for the analytes using cyclic voltammetry (CV) and differential pulse voltammetric (DPV) technique. Specific parameters including varying concentration of analytes, sweep rate and pH solution were optimized to the electrode. The kinetic property of a modified electrode was got to be both adsorption and diffusion controlled and it give lower detection limit for CC (0.11 µM) and HQ (0.16 µM) respectively. In the simultaneous electroanalysis, bare PGE was failed to depict the oxidation peaks, whereas modified electrode gives well separated three anodic peaks for CC, HQ and RS with superior enhancement in peak current. The proposed modified electrode was applied for the quantification of CC, HQ and RS in a tap water and obtained a consistent recovery in-between 96 and 100 %. The proposed sensor can be fabricated using a simple method with a low cost.

A remarkable enhancement between optical transparency and SHG efficiency on doped-KHP single crystals

Potassium hydrogen phthalate (KHP) single crystals are non-linear optical materials and their transmittance window are remarkably enhanced by an organic dopant such as resorcinol. The present study was mainly focused on the growth and characterization of the single-crystal KHP doped with resorcinol which was synthesized by a slow evaporation solution technique and its dimension was found to be $$8 \times 7 \times 2.75 \hbox { mm}^{3}$$ at ambient temperature. Vibrational assignments of the functional groups confirmed the presence of dopants. The optical behaviour of the grown crystal was explored by ultraviolet–visible–near-infrared studies which result in 99% of the transmittance with the cut-off wavelength of 250 nm. The mechanical property was analysed by the Vickers microhardness test. The apparent microhardness increases with increasing applied indentation load revealing the reverse indentation size effect behaviour. Organic impurity increases the second harmonic generation efficiency of KHP, suggesting that the molecular alignment in the presence of resorcinol results in enhanced non-linearity.

Glycoluril Clips for the Construction of Chemoresponsive Supramolecular Polymer Networks through Homodimer Cross-Links.

The formation of polymer supramolecular networks exhibiting selective sensitivity toward a narrow class of organic compounds is still a significant challenge within the area of reversibly cross-linked materials. Glycoluril molecular clips are U-shaped molecules, which, besides the ability to undergo self-sorting homodimerization, exhibit selectively high molecular recognition of dihydroxyaromatic species. A glycoluril clip diol was introduced into a polymer backbone by using standard polyurethane chemistry. Immobilization of the molecular clip along the polyurethane macromolecule (Glyc Clip-polyurethane) was shown to preserve the native association properties of the clip. Clip motifs embedded in macromolecules form homodimer cross-links in CHCl3 and the resulting structures have a thermoresponsive character. The strength of homodimerization Khomodimer varies from 7.74 104 l mol-1 at 265 K to 9.47 102 l mol-1 at 315 K. A 30 wt % solution of Glyc Clip-polyurethane undergoes gelation at room temperature and exhibits a constant elastic modulus, approximately 3.1 ⋅ 104 Pa, in the broad investigated frequency range. The obtained organogels exhibit selective chemoresponsive properties in the presence of resorcinol, which was demonstrated with 1 H high-resolution magic-angle-spinning NMR spectroscopy and rheological measurements.

Pre-treated glassy carbon electrode sensor for catechol: A voltammetric study

The surface of glassy carbon electrode (GCE) was modified by electrochemical pre-treatment method and has been employed for the cyclic voltammetric determination of catechol (CC) in the presence of resorcinol (RS) in 0.2 M phosphate buffer solution (pH 7.4) with scan rate 50 mV s−1. The electrochemical oxidation of catechol (CC) and resorcinol (RS) was investigated by both cyclic voltammetry (CV) and differential pulse voltammetric (DPV) methods at pre-treated glassy carbon electrode (PGCE). The modified electrode (PGCE) showed excellent electrocatalytic activity towards CC and RS determination. The parameters like effect of scan rate, concentration, and interference study were investigated at PGCE. The electrode process was found to be adsorption-controlled at PGCE. Furthermore, the modified electrode exhibited good limit of detection (CC = 0.94 μM, RS = 0.72 μM) and limit of quantification (CC = 31.5 μM, RS = 24.1 μM) for CC and RS. Hence, the pre-treated glassy carbon electrode shows good electrocatalytic properties and can be applied for the determination of CC and RS individually and simultaneously.

In Situ Fluorogenic and Chromogenic Reactions for the Sensitive Dual-Readout Assay of Tyrosinase Activity.

As a well-known copper-containing oxidase, tyrosinase has been anticipated to serve as the biomarker of skin diseases. We describe here an exquisite label-free fluorescent and colorimetric dual-readout assay of its activity, inspired by the specific oxidation ability of monophenolamine substrates to catecholamines and a unique fluorogenic reaction between resorcinol and catecholamines. By employing commercially available tyramine as the model substrate (dopamine as the product), it is found that the tyrosinase-incubated tyramine solution exhibits obvious pale yellow with intense blue fluorescence in the presence of resorcinol and O2, where the absorbance and fluorescence intensity are directly related to the concentration of added tyrosinase (i.e., the amount of conversion of tyramine to dopamine). The overall process of sensing tyrosinase activity takes less than 100 min at ambient temperature and pressure conditions with exceedingly simple operation procedure, explicit response mechanism, and formation of fluorophore with high quantum yield from scratch. Furthermore, such a convenient, rapid, cost-effective, and highly sensitive dual-readout assay exhibits promising prospect for the tyrosinase activity in extensive bioassays and clinic research as well as in screening potential tyrosinase inhibitors.

Fluorescence quantification of allantoin in biological samples by cap-immobilized allantoinase/resorcinol assay

Abstract Allantoin, the final product of urate degradation in non-hominoid mammals, forms in vivo through an enzyme-dependent pathway whose restoration has been proposed for the treatment of hyperuricemic conditions. Non-enzymatic urate oxidation to allantoin also occurs, making it a potential biomarker of oxidative stress in human physiology and pathology. This justifies the quest for fast and accurate methods for allantoin quantification overcoming the limitations of the current approaches, ranging from chromatographic to mass spectrometry techniques. We propose a simple fluorimetric assay that includes an enzymatic step for the conversion of S -allantoin to allantoate, followed by acid hydrolysis of the latter into glyoxylate in the presence of resorcinol. The lactone forming upon reaction of glyoxylate with resorcinol, in basic conditions, exhibits strong and stable fluorescence emission in the visible range. The assay proved to be specific for allantoin, with a linear response in the range of physiological values for several biological fluids, such as serum, urine, and saliva. We also verified the lack of reactivity by the most common interferents, including urate and its degradation intermediates. The assay, which does not require sophisticated instrumentation other than a conventional spectrofluorometer or a lab bench plate reader, was implemented on a solid support, exploiting enzyme encapsulation in a silica gel matrix, to allow reusability and improve stability over time.

Three-Component Reaction of Benzothiazole, Acetylenic Esters, Phenoles; Synthesis of Dialkyl 2-benzo[d]thiazol Derivatives Under Grinding.

Due to biological activity of a significant number of compounds containing benzothiazole ring system and in continuation of our interest in developing new environmentally benign methods for the synthesis of heterocyclic compounds by MCRs in this study we performed an efficient three-component from benzothiazole, acetylenic esters and hydroxyl aromatics compounds to synthesize of 2- benzothiazole derivatives in high yield. IR spectra were recorded using an FTIR apparatus. Melting points measured on an Electrothermal 9100 apparatus. Spectra were obtained in solution of CDCl3 using TMS as internal standard. Elemental analyses were carried out using a Heracus CHN-O- Rapid analyzer. A mixture of benzothiazole, dimethyl acetylenedicarboxylate and phenol were placed in a mortar. The mixture was ground with a mortar and pestle at room temperature for 12 min. After completion of the reaction, as indicated by TLC (ethyl acetate: n-hexane, 1: 3), the solvent was distilled off under reduced pressure and the residue was crystallized from diethyl ether. Treatment of benzothiazole and dialkyl acetylenedicarboxylates in presence of resorcinol and β-naphthol led to products 4 (dialkyl (E)-2-(2-(2-hydroxyphenyl)benzo[d]thiazol-3(2H)-yl-3- methylbut-2-enedioate), while we observed two isomer (Z) and (E) configurations (major and minor) in nearly 70:30 ratio when the reaction was repeated in presence of 8-hydroxy quinolone and DMAD. Also when we examined 2-nitro phenol, 4-nitrophenol, and 4-hydroxy quinoline, only one product 5 was obtained. This indicates that the reaction proceeds efficiently with electron-releasing substituted phenols. The reaction between benzothiazole and dialkyl acetylenedicarboxylates in the presence of some phenols without electron-withdraw substitution, presents a novel, one-pot, clean, convenient, simple and inexpensive approach into the synthesis of 2-benzothiazole derivatives of potential synthetic and pharmacologically interest. This procedure carries significant advantages because of the minimization of labor, time, and cost.

A GREENER APPROACH FOR THE DEGRADATION OF DYE METHYLENE BLUE BY ORGANIC ADDITIVE CATALYSED PHOTO - FENTON PROCESS

Fenton and photo-Fenton processes are proven to be most promising techniques for the wastewater treatment methods. It provides an attractive method for degradation of dyes and breaks them into simple mineral form. These are cost effective and ecologically viable techniques with additional advantages of relatively simple approach, use of less hazards chemicals for the degradation and cyclic nature. Thus, it serves as a green chemical and eco-friendly pathway in reducing pollution caused by complex dye molecule and other organic compounds. Present work has been designed to investigate photochemical degradation of dye Methylene blue by photo-Fenton reaction in presence of resorcinol as an additive. Kinetic study of the reaction has been made by using spectrophotometric techniqueEffect of variation of various operating parameters such as pH, concentration of Fe3+ ion, dye and additive; amount of H2O2 and light intensity has also been observed. A tentative mechanism for the photo-Fenton reaction in presence of organic additive is also given.

Enhancement of Fenton and photo-Fenton processes at initial circumneutral pH for the degradation of the β-blocker metoprolol

The need for acidification in the Fenton and photo-Fenton process is often outlined as one of its major drawbacks, thus in this work the acidification of the Metoprolol (MET) is avoided by the addition of resorcinol (RES), which is used to simulate model organic matter. The experiments were carried out at natural pH (6.2) with different Fe2+ (1, 2.5, 5, and 10 mg/L) and H2O2 (25, 50, 125 and 150 mg/L) concentrations. The performance of MET and RES degradation was assessed along the reaction time. Working with the highest concentrations (5 and 10 mg/L of ferrous iron and 125 and 150 mg/L of H2O2) more than 90% of MET and RES removals were reached within 50 and 20 min of treatment, respectively, by Fenton process. However a low mineralization was achieved in both cases, likely, due to by-products accumulation. Regarding to photo-Fenton process, within 3 min with the highest iron and hydrogen peroxide concentrations, a complete MET degradation was obtained and 95% of RES conversion was achieved. Parameters such Total Organic Carbon, Chemical Oxygen Demand, and AOS were measured. Intermediates were identified and MET degradation path was proposed in the presence of resorcinol. Finally, a comparison between Fenton and photo-Fenton processes at acid pH and at initial circumneutral pH was discussed. The positive effect of RES on Fenton and photo-Fenton systems has been confirmed, allowing the work at circumneutral pH.

γ-Resorcylate catabolic-pathway genes in the soil actinomycete Rhodococcus jostii RHA1.

The Rhodococcus jostii RHA1 gene cluster required for γ-resorcylate (GRA) catabolism was characterized. The cluster includes tsdA, tsdB, tsdC, tsdD, tsdR, tsdT, and tsdX, which encode GRA decarboxylase, resorcinol 4-hydroxylase, hydroxyquinol 1,2-dioxygenase, maleylacetate reductase, an IclR-type regulator, a major facilitator superfamily transporter, and a putative hydrolase, respectively. The tsdA gene conferred GRA decarboxylase activity on Escherichia coli. Purified TsdB oxidized NADH in the presence of resorcinol, suggesting that tsdB encodes a unique NADH-specific single-component resorcinol 4-hydroxylase. Mutations in either tsdA or tsdB resulted in growth deficiency on GRA. The tsdC and tsdD genes conferred hydroxyquinol 1,2-dioxygenase and maleylacetate reductase activities, respectively, on E. coli. Inactivation of tsdT significantly retarded the growth of RHA1 on GRA. The growth retardation was partially suppressed under acidic conditions, suggesting the involvement of tsdT in GRA uptake. Reverse transcription-PCR analysis revealed that the tsd genes constitute three transcriptional units, the tsdBADC and tsdTX operons and tsdR. Transcription of the tsdBADC and tsdTX operons was induced during growth on GRA. Inactivation of tsdR derepressed transcription of the tsdBADC and tsdTX operons in the absence of GRA, suggesting that tsd gene transcription is negatively regulated by the tsdR-encoded regulator. Binding of TsdR to the tsdR-tsdB and tsdT-tsdR intergenic regions was inhibited by the addition of GRA, indicating that GRA interacts with TsdR as an effector molecule.

Synthesis and characterization of ion-imprinted resin for selective removal of UO2 (II) ions from aqueous medium.

In this work, uranyl ion-imprinted resin based on 2-(((4-hydroxyphenyl)amino)methyl)phenol was synthesized by condensation polymerization of its uranyl complex in presence of resorcinol and formaldehyde cross-linkers. Numerous instrumental techniques including elemental analysis, Fourier transform infrared spectroscopy, ultraviolet, (1) H along with (13) C nuclear magnetic resonance spectroscopy have been employed for complete characterization of the synthesized ligand and its uranyl complex. Additionally, the obtained ion-imprinted and non-imprinted resins were investigated using scanning electron microscope and Fourier transform infrared spectroscopy. The effects of various essential parameters such as pH, temperature and contact time on removal of uranyl ions have been examined, and the results indicated that the obtained resin exhibited the optimum activity at pH 5. Furthermore, the adsorption process was spontaneous at all studied temperatures and followed the second-order kinetics model. Also, Langmuir adsorption isotherm exhibited the best fit with the experimental results with maximum adsorption capacity 139.3 mg/g. Moreover, the selectivity studies revealed that the ion-imprinted resin exhibited an obvious affinity toward the uranyl ions in presence of other metal ions compared with the non-imprinted resin.