Spectrophotometric Determination Of Trace Amounts Research Articles

Solution structure, crystal structure, Hirshfeld surface analysis of copper(II) diamide species as an optical chemical sensor

Optical chemical sensors are promising tools for the detection of metal ions in various samples. Copper(II) has received significant attention among metal ions due to its toxic nature and widespread applications in various industrial processes. In recent years, several optical chemical sensors have been developed to detect copper(II) with high sensitivity and selectivity. This paper describes the spectrophotometric determination of trace amounts of copper(II) using N1-(2-aminoethyl)-N2-((pyridin-2-yl)methyl)oxalamide (H2(555)NH2) as an optical chemical sensor. The protonation and formation constants of the Cu(II)/(H2(555)NH2) system were determined at 25 °C and the ionic strength of 0.15 mol dm−3 using glass electrode potentiometry. The structures of the different species, present in solution at different pH values, were determined using UV–vis, 1H NMR, and EPR spectroscopic techniques. At pH 5, the [Cu(H2(555)NH2)]2+ species was formed with the Cu(II) coordinated to the pyridole nitrogen and the terminal amine. Above pH 8, [Cu(H2(555)NH2)H-2] is the most predominant species in solution. Here the Cu(II) coordinates to all four nitrogen atoms. In the solid state, a dinuclear complex, [Cu(H(55)NH3)Cl]2[Cu(H2O)2(NO3)2Cl2]H2O, was formed. Single crystal X-ray structure showed the Cu(II) to be coordinated to the pyridine and the amide N-atoms in addition to an O-atom from one of the two carbonyl groups. The coordination environment was completed by two bridged chloride ions to give a slightly distorted trigonal bipyramidal coordination geometry around the copper centre. The amine was not coordinated. The proposed sensor was successfully applied to determine copper(II) in real samples, with recoveries ranging from 10−5 to 10−3 mol/dm−3. Using H2(555)NH2 as an optical chemical sensor emerged as a powerful tool for detecting copper(II) ions in different aqueous samples.

Spectrophotometric Determination of Trace Amount of Nitrite in Water and Soil

A simple, sensitive, rapid and economical spectrophotometric method for the determination of trace amount of nitrite present in the water and soil samples is investigated. This method is based on the diazo-coupling reaction where nitrite reacts with p-nitroaniline in presence of hydrochloric acid to form diazonium cation which is subsequently coupled with 1-naphthol in presence of sodium hydroxide to form a stable azo-dye. The absorption maximum (λmax) for azo-dye is found to be 610 nm and the method obeys Beer-Lambert’s law at this analytical wavelength over the concentration range 0.02-0.12 μg/mL of nitrite. The molar absorptivity is found to be 3.29 x 104 liter.mol-1cm-1.

Spectrophotometric Determination of Trace Amount of Total FeII/FeIII and Live Cell Imaging of a Carboxylato Zn(II) Coordination Polymer.

The coordination polymer, (Zn(II)-CP, 1), {[Zn(2,6-NDC)(4-Cltpy)](H2O)4} (1) (2,6-H2NDC = 2,6-naphthalene dicarboxylic acid and 4-Cltpy = 4'-chloro-[2,2';6',2″]terpyridine) is structurally characterized by single crystal X-ray diffraction measurement and other physicochemical studies (PXRD, FTIR, thermal analysis, microanalytical data). 4-Cltpy acts as end-capping ligand, and NDC2- is a carboxylato bridging motif to constitute ZnN3O2 distorted trigonal bipyramid core that propagates to construct 1D chain. The coordination polymer, 1, detects total iron (Fe3+ and Fe2+) in aqueous solution by visual color change, colorless to pink. Absorption spectrophotometric technique in aqueous medium measures the limit of detection (LOD) 0.11 μM (Fe2+) and 0.15 μM (Fe3+), and binding constants (Kd) are 6.7 × 104 M-1 (Fe3+) and 3.33 × 104 M-1 (Fe2+). Biocompatibility of 1 is examined in live cells, and intracellular Fe2+ and Fe3+ are detected in MDA-MB 231 cells. Zn(II) substitution is assumed upon addition of FeIII/FeII solution to the suspension of the coordination polymer, 1, in water-acetonitrile (41:1) (LZnII + FeIII/II → LFeIII + ZnII, where L is defined as coordinated ligands), which is accompanied by changing from colorless to pink at room temperature. The color of the mixture may be assumed to the charge transfer transition from carboxylate-O to Cltpy via Fe(II/III) bridging center (carboxylate-O-Fe-CltPy). The product isolated from the reaction is finally characterized as Fe(III)@1-CP. It is presumed that product Fe(II)@1-CP may undergo fast aerial oxidation to transform Fe(III)@1-CP. The FeIII exchanged framework (Fe(III)@1-CP) has been characterized by PXRD, IR, TGA and energy dispersive X-ray analysis (EDX)-SEM. The MTT assay calculates the cell viability (%), and the tolerance limit is 100 μM to total Fe2+ and Fe3+.

Spectrophotometric determination of trace amount of iron in water, food, and pharmaceutical samples

The present study aimed to determine the trace amount of iron by using highly selective and sensitive spectrophotometric reagents in water, food, and pharmaceutical samples. For this, as-triazine containing ferroin-yielding chromogens; 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine (PDT) and 3-(2-pyridyl)-5,6-bis(p-methoxyphenyl)-1,2,4-triazine (PBMPT) have been synthesized. The absorptiometric characteristics of the iron(II) complexes with PDT and PBMPT such as complex formation, sensitivity determination, composition determination have also been studied. It has been observed that these highly sensitive and selective ferroin-yielding reagents act as bidentate ligands and form intensive colored tris-complexes with iron(II) ions. The application of these spectrophotometric reagents for the determination of iron in water, food, and pharmaceutical samples has been described. Bangladesh J. Sci. Ind. Res.56(4), 299-306, 2021

Spectrophotometric determination of trace amounts of Sb(III) and Sb(V) in water and biological samples by in-tube dispersive liquid–liquid microextraction and air-assisted liquid–liquid microextraction

Spectrophotometric determination of trace amounts of Sb(III) and Sb(V) in water and biological samples by in-tube dispersive liquid–liquid microextraction and air-assisted liquid–liquid microextraction

4, 4’-Diantipyrylmethane (DAM): A tool for spectrophotometric microdetermination of cerium (IV)

A simple and hasty method has been employed for the direct spectrophotometric determination of trace amount of Ce(IV) using a complexing agent 4,4’-diantipyryl methane (DAM) with absorption maximum at 445-455nm in acidic medium at 1.3 -1.5 pH. Molar absorptivity and Sandell’s sensitivity were calculated to be 9.1 × 103 l mol-1 cm-1 and 0.015 μg Ce cm-2. Beer’s law was found to be defensible over the cerium concentration range of 0-5.5 μg ml-1. Effect of large number of cations, anions and complexing agents was also studied and several analytically important ions do not cause interference in the procedure except thiourea and EDTA. The method has good reproducibility and has been satisfactorily applied in the determination of cerium in samples.

Preparation and Identification of Metal Ions Complexes for 4-(P-Phenyl azo sulfonic acid)-1-Naphthol Dye

The organic reagent, 4-(p-phenyl azo sulfonic acid)-1-naphthol), was found to be sensitive and selectivereagent for the spectrophotometric determination of trace amounts of Cobalt and Nickle. The preparedcomplexes and azo reagent were characterized using FT-IR and UV-Vis spectroscopic method. The complexeshave a maximum absorption at (453) nm and (446) nm for both Cobalt (II) and Nickle (II(respectively,Beer›s law was obeyed in the range (0.5-2.5) ppm of Cobalt and molar absorptivity ? = 3.24 × 104 L.mole-1.cm-1, as for Nickle, the range was (0.1-2) ppm and molar absorptivity ? =) 0.96×104(L.mol-1.cm-1. Theaccuracy and reproducibility of the determination method for various known amounts of cobalt (II) andNickle (II(were tested . The results obtained are both precise (RSD was better than 1.6 %, 3 %) for bothCobalt (II) and Nickle (II(respectively and accurate (relative error was better than 1 %, 2 %) for both Cobalt(II) and Nickle (II(respectively

Spectrophotometric determination of trace amount of Vanadium in rise and flour using 1-[(4-antipyl azo)] 2-Naphthol as new chromogenic spectrophotometry

The study included follow-up of the interaction of the prepared reagent 1- (4 -Anti-pyrail-Azo) 2- naphthol (APANOL) with vanadium (V) ion, which gave a greater wavelength of absorption (533) nm as well as a study of the best conditions of the size and concentration of the reagent (1 × 10-3) molar and acidic function (pH = 3) and the stability of the complex for more than two hours and temperature from 10 to 40 degrees Celsius and the linearity range falls within the concentrations (0.10-4.00) ppm and correlation coefficient (R2 = 0.9945) and the value of molar absorption coefficient ε (1.02 x 104) l. Mol-1 cm-1 and sandal allergy (0.004) micrograms cm-2. And determined the accuracy and accuracy of the analytical method followed using standard solutions of ion with a standard concentration of the reagent, so the frequency (RSD %) with respect to concentrations (2.00, 3.00) ppm of vanadium ion (V) equal to (0.9 and 0.9), Erel. %) Was equal to (0.2, 0.3) %

Deep eutectic solvent-based ligandless ultrasound-assisted liquid-phase microextraction for extraction of cobalt ions from food samples prior to spectrophotometric determination

An innovative environmentally friendly deep eutectic solvent-based ligandless ultrasound-assisted liquid-phase microextraction was introduced for spectrophotometric determination of trace amount of cobalt. n-phenyliminodiacetic acid: choline chloride (2:1 mol ratio) as a novel DES was prepared for extraction of cobalt ions which is both as chelating agent and extraction solvent. The pivotal factors affecting the proposed method including pH, time, temperature, extraction solvent volume, ionic strength, and sample volume were investigated. At optimum conditions, limit of detection and limit of quantification of 5.23 µg L−1 and 17.67 µg L−1 were achieved respectively. The linear range of 20–200 µg L−1 and precision (relative standard deviation %) of 3.4 for 100 µg L−1 Co+2 solution were gained. The proposed method was successfully applied in water samples, tomato sauce, black and green tea, and dark chocolate with high recovery values (%) of 94–105.

Cloud Point Extraction for Pre-Concentration and Spectrophotometric Determination of Trace Amounts of Silver Ions

During the last years, the cloud point extraction was applied for determination, separation, and enrichment of the elements. The current study used cloud point extraction (CPE) for the extraction of Ag(I) ions pre-concentration from watery solutions by a non-ionic surfactant (Triton X-114) and chelating agent a 6-(4-bromo-phenylazo)m-anisidine[6-(4-BrPAA)], then estimation by using the spectrophotometry at 514 nm. Several condition effects on the efficiency of the cloud-point extraction included Triton X-114 concentration, [6-(4-BrPAA)] concentration, pH, time, and incubation temperature. The silver reacts with [6-(4-BrPAA)] to produce complex at a ratio of one to one. 0.009 to 1.5 μg mL-1 is the range of linearity. The detection limit and quantification of Ag(I) ion were 0.0054 and 0.0182 μg mL-1, respectively. The interference of the cations was examined. The cloud-point extraction was used for the evaluation of silver concentration in the water specimen.

Spectrophotometric Determination of Trace Amounts of Benzotriazole in Aqueous Solutions Using Gold Nanoparticles: Artificial Neural Network Modeling

AbstractIn this study, ultraviolet–visible (UV–Vis) spectrophotometry method was applied to determine benzotriazole (BTA) in aqueous solutions based on surface plasmon resonance (SPR) property of gold nanoparticles (AuNPs). The experimental variables such as pH, time, the volume of various buffers, the concentration of different electrolytes, and concentrations of AuNPs were investigated. Under optimum conditions, the proposed method represented a linear range between 10 to 150 μg L−1 (R2= 0.9941) with a detection limit (LOD) of 5 μg L−1. This method was successfully used to measure trace amounts of BTA in Ahwaz drinking water and Ramin power plant cooling water samples. The proposed spectrophotometry assay is accurate, low‐cost, simple, and does not need any separation steps compared to the other methods. In the next step, an artificial neural network (ANN) using Levenberg‐Marquardt (LM) and Resilient Back propagation (RP) algorithms, was used to predict the absorbance of the mentioned factors. For each algorithm, 2 layers and for each layer 2,4,6,8, and 10 neurons were studied. According to mean square error (MSE) and coefficient of determination (R2), the LM algorithm was better than the RP algorithm for the prediction of absorbance.

Bir Hidroksiazo Bileşiği Kullanılarak Gerçek Örneklerde Nikelin Eser Miktarlarının Spektrofotometrik Tayini

Bu makalede, nikel tayini için, herhangi bir ön deriştirme işlemi uygulamadan, pH 5,5 (5-6) 'da 2,3,4,6/-tetrahidroksi-3/-sülfoazobenzen (THSA) ile şelat oluşturarak seçici ve duyarlı bir spektrofotometrik yöntem önerilmiştir. Metal ligand oranı 1: 1 olan kompleksin, 485 nm'de, molar absorplama katsayısı 1,60 ×104 L mol−1 cm−1 'dir. Kompleks bileşik 3 saat kararlılığını korumaktadır. Ayrıca, 50 °C’ye kadar bozulmadan kalır. Geliştirilen yöntem 0,040-2,348 µg mL−1 Ni (II) tayin aralığında Beer’in kanununa uyar. Toprak alkali elementler, alkalin elementler, nadir toprak elementler, halojenürler, fosfatlar, askorbik asit ve katyonlar nikel tayini engellemez. Önerilen yöntem hızlı ve basittir ve nikel tayini için sertifikalı alaşımlara ve çevre suyu örneklerine kolayca uygulanabilir.

Synthesis, characterisation and application of ZnO-bentonite nanocomposite for preconcentration and spectrophotometric determination of trace amounts of bromocresol purple in water and wastewater samples

ABSTRACTZnO nanocomposite was synthesised by immobilisation of ZnO nanoparticles on sodium bentonite surface and the prepared nanocomposite (nZnO-Bn) was used to remove, preconcentrate and to determine spectrophotometrically trace amounts of an anionic dye (bromocresol purple, BCP) in tap, Nile, sea and industrial water samples. nZnO-Bn was characterised via X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and Brunauer–Emmett–Teller (BET) technique. Factors effect on BCP removal as shaking time, solution pH, BCP initial concentration and temperature was explored in a batch mode. In addition, sorption kinetics, isotherms, thermodynamics, and reusability were studied. Pseudo-second-order kinetic model explained well the experimental results. Freundlich isotherm has been found to have a high correlation coefficient. The sorbed BCP was successfully desorbed using acetone and determined spectrophotometrically. The nZnO-Bn nanocomposite could be regenerated efficiently and recycled up to the fifth cycle with a removal efficiency of more than 83%. The proposed method for BCP determination provided a wide linear range from 15.63 to 2000 μg L−1 of BCP. Moreover, the recoveries of BCP from spiked water samples ranged from 90.34% to 100.12%, indicating the suitability of nZnO-Bn as an efficient sorbent for the removal and determination of BCP in real samples.

Spectrophotometric Determination of Trace Amounts of Cu (II) in Water Samples after Micelle-Mediated Extraction

Spectrophotometric Determination of Trace Amounts of Cu (II) in Water Samples after Micelle-Mediated Extraction

Catalytic spectrophotometric determination of trace amount of cerium(IV)

Based on a property that in dilute hydrochloric acid hydrogen peroxide oxidizes Ponceau S to fade and cerium(IV) has a catalytic effect on the reaction, a new spectrophotometric method was developed for the determination of trace cerium(IV). At 450 nm, the cerium(IV) concentration presents a good linear relationship over the range of 0.08‒4 μg/mL with the fading degree ΔA. Its linear regression equation is ΔA = 0.0475c (μg/mL) + 0.0007, with a correlation coefficient of 0.9991. The detection limit of method is 0.05 μg/mL. The method has been successfully applied to the determination of cerium in water and molecular sieve samples with good results. The relative standard deviations of eleven determinations were 0.97‒1.11 and 0.19‒1.01%, respectively. The recoveries of standard additions were 99.4‒99.9 and 99.2‒101.0%, respectively. The reliability of this method was certified by parallel determination against the dibromo-p-chlorochlorophosphonazo spectrophotometry.

Removal and Spectrophotometric Determination of Anionic Dye Using a Polymeric Nanocomposite

Removal and spectrophotometric determination of trace amounts of methyl orange (MO) in tap and Nile water using silver nanoparticles (AgNPs) supported over polyurethane foam were successfully carried out. AgNPs and samples of a nanocomposite of polyurethane foam and silver nanoparticles (PUF/AgNPs) were characterized using UV–vis spectroscopy, field‐emission scanning electron microscopy (FE‐SEM), and Fourier transform infrared spectroscopy (FTIR). Several parameters affecting dye removal such as pH, contact time, initial dye concentration were investigated. Sorption isotherms, kinetics, thermodynamics, desorption, and nanocomposite reusability were investigated. Error analysis data showed the high suitability of the Freundlich model and the pseudo‐second‐order kinetic model for better interpretation of the experimental data. The sorbed MO was desorbed and determined spectrophotometrically. Under the optimized conditions, the calibration curve was linear from 50 to 1000 μg/L with a correlation coefficient 0.9987. The recoveries of the dye ranged from 96.43% to 103.65%, indicating the excellent performance of the proposed method for MO determination in real samples.

Preconcentration and spectrophotometric determination of trace amount of formaldehyde using hollow fiber liquid-phase microextraction based on derivatization by Hantzsch reaction

Formaldehyde is known as a highly toxic compound to humans and identified as a carcinogenic substance. In this study, Hantzsch reaction was utilized for the derivatization of trace amounts of formaldehyde in aqueous samples with acetylacetone in the presence of ammonia to form an extractable colored product named 3,5-diacetyl 1,4-dihydrolutidine (DDL) and its further extraction using two-phase hollow fiber liquid-phase microextraction. The main experimental variables affecting the extraction performance were investigated and optimized. Under the optimum conditions (sample volume 12 mL; reaction temperature 70 °C; ammonium acetate buffer solution 4 mL 0.1 mol L−1; acetylacetone 5 mL 0.15 mol L−1; solvent octanol, salt concentration 20% (w/v) NaCl; pH of donor phase 7.0; stirring speed 400 rpm and extraction time 30 min), the linear dynamic range, limit of detection (LOD as 3Sb/m) and relative standard deviation (RSD %) of the proposed method were obtained as 5–250 μg L−1 (r2 = 0.9979), 3.6 μg L−1 and 2.5%, respectively. Finally, the applicability of the proposed method was examined, and very good results were obtained. The results confirmed the applicability of the proposed method as a versatile, low-cost and sensitive preconcentration method for determination of low concentrations of formaldehyde in aqueous solutions.

Preconcentration and Spectrophotometric Determination of a Naphthalene Analog of Medetomidine Using Modified Maghemite Nanoparticles

A novel and sensitive extraction procedure using sodium dodecyl sulfate (SDS) modified maghemite nanoparticles (MNPs) as an efficient solid phase has been developed for removal, preconcentration, and spectrophotometric determination of trace amounts of a naphthalene analog of dexmedetomidine (4-(1-(na phthalene-1-yl)ethyl)-1Himidazole, NMED). The MNPs were obtained by a coprecipitation method, and their surfaces were furthermore modified by SDS. The size and morphological properties of the synthesized MNPs were determined by X-ray diffraction analysis, FT-IR, vibrating sample magnetometry, and scanning electron microscopy. NMED was adsorbed at pH 3.0. The adsorbed drug was then desorbed and determined by spectrophotometry at 280 nm. The calibration graph was linear in the range 1 × 10–6–1 × 10–4 mol/L of NMED with a correlation coefficient of 0.989. The detection limit of the method for NMED determination was 3.7 × 10–7 mol/L. The method was successfully applied to the determination of NMED in human urine samples.

Rapid spectrophotometric determination of trace amounts of azorubine dye in food samples after dispersive liquid-liquid microextraction

Rapid spectrophotometric determination of trace amounts of azorubine dye in food samples after dispersive liquid-liquid microextraction

Rapid spectrophotometric determination of trace amounts of azorubine dye in food samples after dispersive liquid-liquid microextraction

Rapid spectrophotometric determination of trace amounts of azorubine dye in food samples after dispersive liquid-liquid microextraction