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Flame Retardants: Analytical Aspect of Brominated Flame Retardants
Published in Narendra Kumar, Vertika Shukla, Persistent Organic Pollutants in the Environment, 2021
Devendra Kumar Patel, Sandeep Kumar, Neha Gupta
Solid-phase extraction (SPE) is a technique in which compounds are separated from each other in a mixture according to their physical and chemical properties. It is effective in extraction from different matrices such as urine, water, blood, beverages, soil, and animal tissue, and especially in determining neutral and acidic BFRs in human plasma (Thomsen et al., 2001a, 2001b). Plasma is mixed in a mixture of isopropanol and formic acid and then sonicated, after which it is diluted and then transferred to the conditioned SPE column (made of polystyrene-divinylbenzene), followed by washing the SPE column with a mixture of water and isopropanol. The lipids retained in the column are directly decomposed by adding sulfuric acid, followed by again washing the column with methanol, water, and acetate buffer. Finally, a mixture of dichloromethane and water is used for elution of the analyte. Phenolic BFRs can similarly be extracted from human milk using a SPE column made of copolymeric sorbent by copolymerization of divinylbenzene and N-vinylpyrrolidone (Thomsen et al., 2001a, 2001b). To process human plasma, an additional cleanup step is required.
Per- and Polyfluoroalkyl Substance Analysis to Support Site Characterization, Exposure, and Risk Management
Published in David M. Kempisty, Yun Xing, LeeAnn Racz, Perfluoroalkyl Substances in the Environment, 2018
Kavitha Dasu, David M. Kempisty, Marc A. Mills
For aqueous samples, such as surface water, groundwater, drinking water, and wastewater, solid-phase extraction (SPE) is commonly used for separating and concentrating the target compounds from the sample. In general, the sample volume required for analysis varies from 5 to 1000 mL and depends on the SPE media and the sensitivity of the analytical instrument (ISO 2009; Quiñones and Snyder 2009; ASTM 2016). Common SPE phases used for sample concentration and cleanup are weak anion exchange (WAX), hydrophilic–lipophilic balance (HLB), hydrophobic C8, and C18 (Jin et al. 2009; Quiñones and Snyder 2009; Eschauzier et al. 2012). Typically, once the target analytes are bound to the SPE media, matrix interferences are washed off the media using a solvent (e.g., methanol). Further, the target analytes are subsequently eluted using various solvents or solvent mixtures (e.g., ammonium hydroxide in methanol, methyl tert-butyl ether, and methanol solvent mixtures). As PFAS analytes include different functionalities (e.g., sulfonates, carboxylates, and sulfonamides) and diverse chain lengths (e.g., C4–C14), it has been reported that the pH and polarity of the conditioning and elution solvents dramatically effect the analyte recoveries and reproducibility of the method (Taniyasu et al. 2005).
Use of Carbon Nanotubes as Sorbents for Heavy Metal Remediation from Wastewater
Published in Chaudhery Mustansar Hussain, Ajay Kumar Mishra, Nanocomposites for Pollution Control, 2018
Akil Ahmad, David Lokhat, Siti Hamidah Mohd Setapar, Asma Khatoon, Mohammad Shahadat, Mohd Rafatullah
Hence, in spite of the advances in analytical instrumentation, the preconcentration and separation procedures have been employed prior to the determination of metal ions, which decreases the detection limits. Solid phase extraction (SPE) is a most common preconcentration method, which designed for a rapid, selective sample preparation and purification prior to analysis that can be applied for both off-line and online systems. The basic principle of SPE is to transfer the analytes such as trace metal ions from the aqueous phase to the active sites of the solid sorbents. In SPE, solid sorbents are packed in column or microcolumn. After sorption of metal ions on active site of sorbents which can be desorbed with an appropriate eluting agent. Nowadays, various types of solid sorbents, including silica based sorbents, oxides of metals (e.g. aluminium, magnesium, zirconium, titanium and thorium), graphitized carbon or carbon based, polymeric sorbents (synthetic resins and its derivatives, styrene, acrylamide, methacrylic acid or methyl methacrylate) and biological substrates (bacteria, algae or fungus free or immobilized in a solid-support) are used in the solid-phase extraction (Pereira and Arruda, 2003; Camel, 2003).
Microwave-assisted synthesis of magnetic Pb(II)-imprinted-poly(schiff base-co-MAA) for selective recognition and extraction of Pb(II) from industrial wastewater
Published in Journal of Dispersion Science and Technology, 2023
Junde Xing, Na Li, Yukun Liang, Fang Zhu
Solid-phase extraction (SPE) is usually used for extraction and enrichment before quantification steps.[31] Compared with the static adsorption, SPE can determine trace metals in aquatic environment.[32,33] SPE has the advantages of flexibility, economy and environment protection, no emulsification, speed and simplicity, more selectivity and high recovery, etc. Zhao et al.[34] prepared a bimorphic polymer coated magnetic nanoparticles with ZnO and Pb(II) and extracted Pb(II) with a detection limit of 9.4 ng·L−1 and a relative standard deviation of 6.9%. Shah et al.[35] prepared a superparamagnetic lead(II)-imprinted sorbent, appling it to the determination of Pb(II) by SPE. The adsorption equilibrium was reached within 20 min. Moreover, the maximal adsorption amount was 377.76 mg·g−1. Ricky Cassio et al.[36] prepared a lead-ion imprinted polymer by double imprinting method, which was used to determine lead in wastewater by solid phase extraction. The recovery of lead was about 82.0%, and the limits of detection and quantification were 6.3 and 10 μg·L−1, respectively.
Identification of transformation products during Doxylamine chloramination for NDMA mitigation
Published in Environmental Technology, 2022
B. Coskun, N. Bilgin-Saritas, E. Aydin, E. Pehlivanoglu-Mantas
Solid phase extraction (SPE) is a tool to enrich the analytes and decrease matrix effect in samples. SPE was applied to all samples before measurement with LC-MS/MS. The SPE method was described in detail by Topuz et al. [46]. SPE extraction was done with Bakerbond Carbon (1000 mg; Mallinckrodt-Baker, Philippsburg, NJ). The Bakerbond Carbon cartridges were conditioned using 2 × 5 mL of acetonitrile, 2 × 5 mL of HPLC grade water. The 1000-mL aliquots of samples were spiked with internal standard (100 ng of deuterated NDMA). Samples passed at a flow rate of ∼3 mL/min from cartridge under vacuum. Cartridges were rinsed with 5 mL of HPLC grade water, and dried under a vacuum for 1 h. The cartridges were eluted with 2 × 2 mL of acetonitrile and 2 × 2 mL of acetone into a conical flask, respectively. Using Turbovap II instrument (Caliper Life Sciences) under 1 bar pressure of Nitrogen gas at 40°C, eluted solvent was evaporated until 0.75 mL extract was left. The extracts were transferred to 2-mL auto sampler vials after the volumes adjusted volumetrically to 1 mL using HPLC grade water. Before transferring of the extracts to vials were filtered using a 0.22-μm syringe filter.
Solid-phase extraction of phytosterols from rapeseed oil deodorizer distillates with magnetic graphene oxide nanocomposite
Published in Journal of Experimental Nanoscience, 2020
Parisa Jafarian-asl, Razieh Niazmand, Moslem Jahani
Solid-phase extraction (SPE) is a sample preparation technique with a low solvent requirement and high extraction efficiency. SPE found widespread applications for the extraction of desired analytes in environmental [11], food [12], and biological matrices [13]. Also, the isolation of phytosterols described with silica gel [14] and molecularly imprinted polymers [15] as SPE adsorbents. Although, samples with significant amounts of phytosterols mostly have grease nature and can affect the extraction efficiency of traditional C18 SPE-adsorbents [16]. Therefore, the development of new adsorbent materials is necessary for the purification and enrichment of phytosterols.