Adsorbent For Preconcentration Research Articles

Adsorption Preconcentration of Flavonoids on Ordered Mesoporous Silica Synthesized in the Presence of a Potential Adsorbate

Adsorption Preconcentration of Flavonoids on Ordered Mesoporous Silica Synthesized in the Presence of a Potential Adsorbate

Preparation of IL@ZIF-8 composite as a new adsorbent for preconcentration of Cd (II) and Co (II) ions from environmental samples with vortex-assisted dispersive solid phase microextraction

Ionic liquid (IL) was incorporated into a zeolitic imidazolate framework-8 (ZIF-8) under mild conditions. (1)-methylimidazole and 1-bromobutane were combined to form the IL inside the pore structure of ZIF-8 using the ship-in-bottle (SIB) method. The IL@ZIF-8 composite has been thoroughly characterized using X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Brunauer-Emmett-Teller analysis (BET), and Fourier transform infrared spectroscopy (FTIR). IL@ZIF-8 composite was used as a new adsorbent For the preconcentration and measurement of Cd (II) and Co (II) ions in a variety of sample matrices, such as soil, vegetable juice, and water. This methodology was achieved by integrating vortex-assisted dispersive solid phase microextraction (VA-DSPME) and flame atomic absorption spectrometry (FAAS). Under optimal conditions, the method demonstrated a favorable linear dynamic range within the range of 0.001–2 and 0.008–10 µg mL−1, with a lower limit of detection values of 0. 33 and 2.42 µg/L for Cd (II) and Co (II) ions, respectively. Furthermore, the method preconcentration factor was 25 for both metal ions. The relative standard deviations (RSDs) of this work were found to be below 1.0 % for the concentration of 0.5 µg mL−1.

Magnetic graphene oxide functionalized dimercaptosuccinic acid/putrescine as a selective and stable solid-phase extraction adsorbent for preconcentration and speciation of arsenic (III) in water samples

ABSTRACT It is challenging for environmental scientists to identify the trace value of arsenite (As(III)) as an essential hazardous material in the presence of arsenate (As(V)) and other metal ions. This paper proposes a method of magnetic solid-phase extraction (MSPE) for the trace analysis of As(III) using magnetite graphene oxide (MGO) covalently functionalised with dimercaptosuccinic acid (DMSA) and putrescine (PUT). The hydrothermally synthesised MGO/DMSA-PUT adsorbent was carefully characterised by using energy-dispersive X-ray spectroscopy analysis, Fourier transform infrared, dynamic light scattering, scanning electron microscopy, zeta potential analyser, X-ray diffraction, and vibrating sample magnetometer techniques in detail. Maximum adsorption capacity of MGO/DMSA-PUT for As(III) was determined 144 mg g−1 which considerably improved vs. graphene oxide with the adsorption capacity of 54.8 mg g−1. Sample pH of 6 with a volume of 50 mL, contact time of 5 minutes, initial concentration of 50 μg L−1, adsorbent dosage of 0.1 g and volume of eluent 3 mL were obtained as the optimised parameters for the developed MSPE procedure. According to experimental data obtained with hydride generation atomic absorption spectroscopy, the linear range and detection limit of the proposed method for As(III) measurement was found to be 0.4–5000 µg L−1 and 9.914 ng L−1, respectively. According to experimental results, a preconcentration limit (PL) of 1.72 µg L−1 was achieved for As(III), corresponding to a preconcentration factor of 965. Statistical analysis of standard reference materials confirmed the accuracy of the method against systematic and constant errors (>95% recovery with <5% RSD). Because of the selectivity of MGO/DMSA-PUT towards the As(III), the developed MSPE procedure is capable for successful speciation and determination of As(III) in water samples with satisfactory analytical results.

Preparation of modified multiwalled carbon nanotubes (l-Arg-CS/MWCNTs-COOH/Fe3O4) as sorbent for dispersive solid phase extraction of Cu(II), Pb(II) and Cd(II) in wastewater samples

A new modified multiwalled carbon nanotube (l-Arg-CS/MWCNTs-COOH/Fe3O4) as sorbent of dispersive solid phase extraction (DSPE) was synthesized for preconcentration and determination of Cu (II), Pb (II), and Cd (II) in wastewater samples. The successful formation of sorbent was characterized by FTIR (Fourier transform infrared) spectroscopy, SEM (Scanning electron microscope), and XRD (X-ray diffraction). Batch experiments such as solution pH, amount of adsorbent, extraction time, type and volume rate of eluent and etc were achieved to study the sorption process. At optimized conditions the adsorbent shows good recovery with 4mL ethylene diamine tetra acetic acid) EDTA( as eluent. Good fitting of sorption kinetics by pseudo-second-order model was obtained. Limits of detection were found in the range of 0.10-0.12 μg L−1 for metal ions, the liner range was 5-1000 μg L−1 for Cd(II) and 10-1000 μg L−1 for Cu(II) and Pb(II) and the preconcentration factor 60, 65 and 55 for Cu(II), Pb(II) and Cd(II), respectively. The relative standard deviation was in the range of 1.5-2.3 %. Results showed that the new magnetic nanosorbent was an efficient DSPE adsorbent for preconcentration and determination of Cu (II), Pb (II), and Cd (II) in wastewater samples.

Analytical perspective and environmental remediation potentials of magnetic composite nanosorbents.

The synthesis and application of magnetic nanosorbents to remove emerging pollutants have been considered the best environmental remediation and sustainability option. Incorporating magnetism shortens the treatment time and allows the sorbent to be recovered quickly using external magnetic with many cycles. The implementation of magnetic solid-phase extraction (MSPE) using magnetic materials of different shapes, sizes, and surface morphology can be a valuable tool in applying materials to prepare analytical samples. In MSPE applications, materials with strong magnetic domain can be used as precursors for constructing magnetic composite as a promising sorbent. This article focuses on the most recent and exceptional applications of magnetic adsorbents for preconcentration and removal purposes. Magnetic adsorbents, such as nanoparticles (NPs), foam, sponges, nanocomposites, hydrogels, and beads with multifunctional attributes have been comprehensively studied in terms of preparation procedures, limitations, advantages, and interactions between pollutants and magnetic composites. The role of magnetic sorbents in sample preparation methods, such as simple solid-phase extraction and microextraction, as well as sorptive extraction using a stir bar, was also examined. The use of magnetic adsorbents with analytical techniques, such as solid-phase extraction and solid-phase microextraction improves the method for preparing samples concerning the influential role of magnetic adsorbents. Towards the end, promising features and future outlook are also directed.

Development of copper nanoflowers based dispersive solid-phase extraction method for cadmium determination in shalgam juice samples using slotted quartz tube atomic absorption spectrometry

In this work, dispersive solid-phase extraction procedure was developed for trace cadmium determination before flame atomic absorption spectrometry (FAAS) measurement. Copper(II) based nanoflowers were synthesized to utilize as adsorbent for preconcentration of cadmium. The detection power of the spectrometric system was enhanced by placing a slotted quartz tube (SQT) onto the flame burner which increases the residence time of the analyte atoms in the flame region. The analytical performance of the developed system was evaluated with and without SQT equipment and the enhancement in detection power was calculated by the ratio of detection limits of CuNF-DSPE-FAAS (copper nanoflower based dispersive solid phase extraction-flame atomic absorption spectrometry) and FAAS system. Enhancement was determined as 73 and 104.3 times for CuNF-DSPE-FAAS and CuNF-DSPE-SQT-FAAS (CuNF-DSPE-slotted quartz tube-FAAS), respectively. Percent recovery results indicated the applicability of the developed method for the determination of trace cadmium.

Stearic Acid Functionalized Iron Nanoparticle Based Magnetic Solid-Phase Extraction (MSPE) for the Determination of Oxadiazon in Purslane by High-Performance Liquid Chromatography (HPLC)

An accurate, simple, and sensitive method was developed for the determination of the herbicide oxadiazon in purslane. The method was based on magnetic solid phase extraction (MSPE) using stearic acid modified iron oxide nanoparticles (Fe3O4@SA) as the adsorbent for preconcentration, followed by the reverse phase high performance liquid chromatography (HPLC) determination of oxadiazon. The MSPE method was optimized using the univariate approach of optimization, where one parameter was tested at different variables and the other parameters were held constant. Using the optimum conditions, the oxadiazon limits of detection and quantification (LOD and LOQ) were 0.29 and 1.0 ng mL−1. The calibration plot of the method was linear across a broad dynamic range from 1.0 to 1000 ng mL−1 with a coefficient of determination equal to 0.9988. The accuracy and applicability of the method was validated by performing spike recovery experiments with purslane samples. The matrix matching calibration strategy was used to mitigate interferences from the sample to attain recovery values between 90 and 110%. The high recoveries and low standard deviations (<10%) verified the accuracy and precision of the developed protocol.

A magnetic covalent organic framework as selective adsorbent for preconcentration of multi strobilurin fungicides in foods

A new method that utilizes a magnetic covalent organic framework (Fe3O4@BTA-TAPM) as a selective solid-phase extraction adsorbent has been developed for the simultaneous preconcentration of trace eleven kinds of strobilurin fungicides (SFs) in foods combined with ultra-high performance liquid chromatography-tandem mass spectrometry. The preconcentration conditions were optimized, including the adsorbent amount, extraction time, pH value, shaking time, elution solvent, desorption time and the interference ions. The maximum adsorption capacity of the adsorbent was ranging from 42.84 mg g−1 to 54.18 mg g−1 for eleven SFs. The low limits of detection were 0.003–0.072 μg kg−1. The recoveries of eleven SFs spiked at levels of 0.25–1000 μg kg−1 ranged from 80.2% to 109.3%, and the relative standard deviations were <6.8% (n = 3). The utility of the adsorbent was demonstrated to determine traces SFs in four different samples.

Synthesis and comparison of two different morphologies of graphitic carbon nitride as adsorbent for preconcentration of heavy metal ions by effervescent salt-assisted dispersive micro solid phase extraction method

The g-C3N4 (GCN) adsorbent with two different morphologies, coral (CGCN) and nano fiber (GCNNF), was synthesized and recruited for extraction and preconcentration of lead and copper metal ions by effervescent salt-assisted dispersive micro solid phase extraction procedure. The structures of the two adsorbents were affirmed by Fourier-transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy and Brunauer–Emmett–Teller analyses. The factors affecting the extraction efficiency were carefully studied and the optimum values of the parameters for both adsorbents were pH 6.5, adsorbent dosage 8 mg, desorption time 3 min, and the elution solvent 300 μL of 2 mol L−1 of HNO3. The detection limits of Pb(II (and Cu(II) ions for CGCN were 0.9 and 0.3 μgL−1 and for GCNNF were 1.56 and 0.7 μgL−1, respectively. The percent relative standard deviations were obtained to be 1.32% and 2.23% for CGCN (n = 3) and 1.24% and 2.29% for GCNNF (n = 3), respectively for the lead and copper metal ions. In addition, the adsorbents could be used up to 7 times without an imperative reduction in the percentages of analytes recovery. Finally, the performance of CGCN and GCNNF were used for preconcentrate of lead and copper ions in honey, canned fish, and human hair samples.

Adsorption properties of Danthron-impregnated carbon nanotubes and their usage for solid phase extraction of heavy metal ions

Keeping the efficiency of adsorbents in view with devising new solid phase extraction (SPE) methods, this study was aimed at preparation and examination of a new beneficial adsorbent for heavy metal ions. A suitable extractant, 1,8-Dihydroxyanthraquinone (Danthron), was impregnated onto MWCNTs and, firstly, the adsorption properties of Danthron-impregnated MWCNTs (Danthron/MWCNTs) were checked towards some targeted metal ions, i.e. Pb2+, Cu2+, Zn2+, Cd2+, Co2+, and Ni2+ ions. Langmuir isotherm fitted with equilibrium data, kinetic studies vouchsafed the obedience of experimental data from pseudo-second-order model, and thermodynamic appraisals revealed the endothermic nature of adsorption process. Secondly, provided with good sorption properties of the adsorbent, a mini-column packed with Danthron/MWCNTs was recruited for pre-concentration of the interested analytes prior to their determination by inductively coupled plasma (ICP) instrument. The detection limits were in a range between 0.301 and 0.016 µg·L−1 and the new SPE method showed a high efficiency in tackling analysis of natural waters, herbal infusion samples, and certified reference materials. Overall, the results vouchsafed that Danthron/MWCNTs can be regarded as a suitable adsorbent for preconcentration of the targeted metals.

Ethylenediaminetetraacetate functionalized ordered Santa Barbara Amorphous‐15 mesoporous silica as an effective adsorbent for preconcentration of some heavy metals followed by inductively coupled plasma atomic emission spectrometry

AbstractA simple and sensitive method was developed for preconcentration of the several transition metal ions using Santa Barbara Amorphous‐15 mesoporous silica functionalized with the ethylenediaminetetraacetate functional group. The determination of the metal ions was performed by inductively coupled plasma atomic emission spectrometry. The effective parameters on the extraction efficiency of the ions were investigated. The optimized conditions were: the sample solution pH 4, adsorbent amount = 10 mg, adsorption time = 30 min, elution solvent = 1.5 M of HCl, and desorption time = 5 min. Under the optimum conditions, limits of detection of 50, 5, 10, 50, 10, and 500 ng/L were obtained for Co2+, Mn2+, Cu2+, Cd2+, Zn2+, and Fe3+ respectively. The relative standard deviations for determination of the selected metal ions at concentration level of 50 μg/L (n = 4) were in the range of 1.7–5.8%. Linear ranges for Co2+ and Cd2+ (0.1–250 μg/L), Cu2+ and Zn2+ (0.05–250 μg/L), Fe3+ (1–250 μg/L), and Mn2+ (0.01–25 and 50–500 μg/L) were obtained with perfect correlation coefficients (R = 0.9958–0.9996, n = 8). The applicability of the method was evaluated by the extraction and determination of the heavy metal ions in different water samples.

Phytic Acid Functionalized Magnetic Adsorbents for Preconcentration of Trace Rare Earth Elements in Environmental Water and Atmospheric Particulates Followed by Inductively Coupled Plasma Mass Spectrometry Detection

Phytic Acid Functionalized Magnetic Adsorbents for Preconcentration of Trace Rare Earth Elements in Environmental Water and Atmospheric Particulates Followed by Inductively Coupled Plasma Mass Spectrometry Detection

Adsorption Separation of Arsenic(III) and Arsenic(V) using Functionalized Silica Gels

A method for the adsorption separation of inorganic arsenic species (As(III)/As(V)) using sequentially connected preconcentrating columns filled with functionalized silica gels and their determination by inductively coupled plasma optical emission spectrometry was proposed. As(V) was effectively retained at pH 3.5–6.5 by an adsorbent containing groups of quaternary phosphonium bases on the surface and exhibiting the properties of an anion exchanger. In this pH range, As(III) was not extracted, which made it possible to separate As(V) from As(III). As(III) was retained in a wide pH range of 1–6 by a complexing adsorbent containing mercapto groups on the surface. Adsorbed As(V) was quantitatively eluted from the surface with 1M HNO3, and As(III) – with 5 % unithiol solution in 2M HCl. The use of «non-aggressive» eluents allows us to reuse adsorbents for preconcentration of As(III) and As(V) at least 5 times. The separation efficiency was confirmed by the analysis of model solutions

SOLID PHASE EXTRACTION BASED ON Mn3O4-TIO2 NANOCOMPOSITE FOR THE DETERMINATION OF MOLYBDENUM IN WATER SAMPLES

The Mn3O4-TiO2 nanocomposite was applied as a new solid phase adsorbent for preconcentration of Molybdenum before determination by an UV-Vis spectrophotometer. The solid-phase extraction conditions as pH, the mass of sorbent, contact time, stirring speed, and the elution condition were investigated. Under optimized conditions, the adsorption capacity of adsorbent was 20.69 mg/g, and the elution condition was 0.2M NaOH solution. Molybdenum ions were determined based on its catalytic effect on the oxidation of 1-amino-2- naphthol-4-sulfonic acid (ANSA) with H2O2. The linear calibration graph was in the range of 0.2–2.5 µg/L (r2 = 0.995) with a detection limit of 0.0502 µg/L. The relative standard deviation for five measurements of 2 µg/L of Mo (VI) was 3,37%. The method was applied to the determination of Molybdenum in water samples.

Modified magnetic graphene oxide as an efficient adsorbent for preconcentration of tartrazine

In this research, novel magnetic Graphene Oxide/Fe3O4/Thiourea/Cethyltrimethyammonium Bromide nanocomposites were designed and fabricated as an efficient adsorbent in the service of micro-solid phase extraction for preconcentration of Tartrazine (Tar) before UV-Vis spectrophotometric detection. This adsorbent was fully characterized by Fourier Transform Infrared (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Energy Dispersive X-ray (EDX) analysis. The mechanism of Tar adsorption was discussed. The operating parameters affecting preconcentration efficiency and spectrophotometric determination were optimized. Under the optimum conditions, this method exhibited a linear range from 5.0 to 1200.0 ng mL−1 (R2=0.9993), with a detection limit of 1.1 ng mL−1. Relative standard deviations (RSD) for intra (n = 10) and inter-day (n = 8) of Tar (400 ng mL−1) were 2.2 and 4.8%, respectively. The satisfactory results of analysis of real samples indicate that the method is very favored in the analysis of various complex matrices.

Multi-Walled Carbon Nanotubes Magnetic Composite as an Adsorbent for Preconcentration and Determination of Trace Level Vanadium in Water Samples

Magnetic solid phase microextraction (m-SPME) is a well-defined strategy for the preconcentration and separation of hydrophobic species from aqueous samples without the use of toxic organic solvents. This work identifies a new analytical procedure for trace level vanadium(V) by inductively coupled plasma mass spectrometry coupled to magnetic solid phase microextraction. The procedure is based on the preconcentration of the V(V)–H2O2–4-(2-pyridylazo)resorcinol complex. Magnetic Fe3O4 nanoparticles decorated multi-walled carbon nanotubes as an adsorbent were investigated systematically. The calibration curve obtained by using m-SPME for vanadium(V) was linear from 0.011 to 10 µg/L. The method detection limit was found to be 1.5 ng/L. The m-SPME method was applied to the assay of vanadium in a certified reference water sample and the result was in total balance with the declared value. Finally, the proposed method was applied to the determination of vanadium in real water samples.

Magnetic Fe3O4@Mg/Al-layered double hydroxide adsorbent for preconcentration of trace metals in water matrices

A magnetic Fe3O4@MgAl-layered double hydroxide (MLDH) nanocomposite was successfully synthesized and applied as an effective adsorbent for preconcentration of trace As(III), Cd(II), Cr(III), Co(II), Ni(II), and Pb(II) ions from complex matrices. The quantification of the analytes was achieved using the inductively coupled plasma optical emission spectrometry (ICP-OES) technique. The nanocomposite was then characterized using BET, FTIR, SEM, and EDS. Due to its high adsorption surface area, compared to traditional metal oxide-based adsorbents, MLDH nanocomposite exhibited high extraction efficiency. Several experimental parameters controlling the preconcentration of the trace metals were optimized using response surface methodology based on central composite design. Under optimum conditions, the linearity ranged from 0.1 to 500 µg L−1 and the correlation of coefficients (R2) were higher than 0.999. The limits of detection (LODs) and quantification (LOQs) were 0.11–0.22 µg L−1 and 0.35–0.73 µg L−1, respectively. The intra-day (n = 10) and inter-day precisions (n = 5 working days) expressed in the form of percent relative standard deviations (%RSDs) were below 5%. The proposed method was successfully applied for the analysis of the As(III), Cd(II), Cr(III), Co(II), Ni(II), and Pb(II) ions in different environmental water samples.

Cyclodextrin-derivatized hybrid nanocomposites as novel magnetic solid-phase extraction adsorbent for preconcentration of trace fluoroquinolones from water samples coupled with HPLC-MS/MS determination

A novel cyclodextrin-derivatized hybrid magnetic nanocomposite, denoted as Fe3O4@SiO2@CD, was fabricated and employed as the adsorbent of magnetic solid-phase extraction (MSPE) for preconcentration of elven fluoroquinolones (FQs) from water samples. The prepared nanoparticles exhibited excellent magnetic responsiveness (56.7 emu g−1), uniform size distribution (about 300 nm), good thermal and chemical stability, excellent reusability and superior chemical affinities to the target FQs via hydrogen bond, host–guest inclusion complexation and π–π interactions. Under the optimized conditions, the MSPE was coupled with HPLC-MS/MS to sensitively quantify trance levels of FQs in environmental water. The developed method revealed satisfactory precision with RSDs lower than 4%, good linearity (R2 ≥ 0.9981), low limits of detection (0.0014–0.023 µg L−1) and satisfactory recoveries (93.2–105%). Furthermore, the proposed approach was validated by analyzing the Certified Reference Material of GBW 10152 and GBW 10153 chicken meat powder. These results demonstrated that the Fe3O4@SiO2@CD nanoparticles are a promising magnetic adsorbent for FQs, and the established MSPE-HPLC-MS/MS approach is suitable for simultaneous analysis of trace levels of FQs in actual samples.

Magnetic polyamidoamine dendrimer grafted with 4-mercaptobenzoic acid as an adsorbent for preconcentration and sensitive determination of polycyclic aromatic hydrocarbons from environmental water samples

Polyamidoamine dendrimer decorated Fe3O4 magnetic nanoparticles was synthesized and grafted with 4-mercaptobenzoic acid (4-MBA). The resulting material was utilized to develop an effective magnetic solid phase extraction method in combination with high performance liquid chromatography for trace determination of polycyclic aromatic hydrocarbons including phenanthrene (PHE), anthracene (ANT), fluoranthene (FLT), pyrene (PYR) and benzo(a)pyrene (BaP). The MNPs@G3.0@4-MBA exhibited to be an efficient extracting medium due to the existence of terminal benzene ring groups, the internal pores, and strong hydrophobic interactions and π-π interactions. The experiments demonstrated that the proposed method possessed excellent linearity in the concentration range of 0.1–300 μg L−1 with correlation coefficients (R) larger than 0.997, and the limits of detection (LODs, S/N = 3) according to the ratio of signal to noise equal to three of PHE, ANT, FLT, PYR and BaP were 0.014 μg L−1, 0.032 μg L−1, 0.055 μg L−1, 0.027 μg L−1 and 0.039 μg L−1, respectively. The proposed method was applied to real water samples and the spiked recoveries were over the range of 92–99%. The results showed that the method earned good repeatability and high sensitivity, and the as-prepared materials were stable and reusable, which displayed that the proposed method would have a wonderful application prospect.

Amine-functionalized magnetic activated carbon as an adsorbent for preconcentration and determination of acidic drugs in environmental water samples using HPLC-DAD

AbstractIn the present study, a convenient and highly effective method was developed for the quantification of acidic drugs in wastewater and river water samples. Ultrasonic-assisted magnetic solid phase extraction employing magnetic waste tyre-based activated carbon nanocomposite functionalized with [3-(2-aminoethylamino)propyl]trimethoxysilane as a cost-effective and efficient adsorbent was used for the extraction and preconcentration of acidic drugs (naproxen [NAP], ketoprofen (KET) and diclofenac [DIC]). The quantification of target analytes was achieved by high‐performance liquid chromatography with diode array detector. Under optimum conditions, the detection limit, quantification limit and relative standard deviation obtained for the analytes of interest ranged from 0.38 to 0.76, 1.26 to 2.54 µg L−1 and 2.02 to 4.06%, respectively. The applicability of the developed method was assessed by the spike recovery tests and the relative recoveries proved that the method is reliable for the determination of acidic drugs in wastewater. Thereafter, the method was applied successfully for the determination of NAP, KET and DIC in river water, influent and effluent wastewater.