Agarose Based Magnetic Solid-Phase Extraction-Magnetic Field Agitation for Determination of Trace Amounts of Molybdenum in Beans

Biopolymers in sorbent-based microextraction methods

“…In the desorption step, tetrahydrofuran was used as desorption solvent and then injected in the GC-MS system for the determination of the analytes. In m-m-dSPE applications, agarose is combined with ferritebased MNPs to synthesize the magnetic sorbent [111,151,152]. In the method reported by Poursheikhi et al, the MNPs were prepared by the coprecipitation method in presence of agarose to obtain the agarose gel matrix containing MNPs [111].…”

“…In m-m-dSPE applications, agarose is combined with ferritebased MNPs to synthesize the magnetic sorbent [111,151,152]. In the method reported by Poursheikhi et al, the MNPs were prepared by the coprecipitation method in presence of agarose to obtain the agarose gel matrix containing MNPs [111]. In the remaining methods, the dispersion of the MNPs in the agarose gel was accomplished by a water-oil emulsion technique using Span-80 [152] or Span-85 [151] as the oil phase, and the aqueous agarose solution as the water phase.…”

“…In all cases, the sorbent particles were subjected to an epoxy activation step, followed by their functionalization with the aim of improving the selectivity for the target compounds. The reported surface modifications included phenylephrine for the extraction of Mo from beans [111], a Schiff base ligand for the formation of complexes and extraction of UO 2 (II) from waters [151], and an aptamer to selectively extract aflatoxins from maize samples [152]. Trapped analytes are desorbed from the magnetic materials using organic solvents, and subsequently determined by spectrophotometric techniques [111,151] or LC-fluorescence detection [152], depending on the nature of the analytes.…”

“…The reported surface modifications included phenylephrine for the extraction of Mo from beans [111], a Schiff base ligand for the formation of complexes and extraction of UO 2 (II) from waters [151], and an aptamer to selectively extract aflatoxins from maize samples [152]. Trapped analytes are desorbed from the magnetic materials using organic solvents, and subsequently determined by spectrophotometric techniques [111,151] or LC-fluorescence detection [152], depending on the nature of the analytes. It is interesting to mention the magnetic field agitation device reported by Hashemi et al [111,151], which could be programmed to change the magnetic field around the sample cell in order to control the dispersion of the magnetic sorbent through the sample.…”

“…Trapped analytes are desorbed from the magnetic materials using organic solvents, and subsequently determined by spectrophotometric techniques [111,151] or LC-fluorescence detection [152], depending on the nature of the analytes. It is interesting to mention the magnetic field agitation device reported by Hashemi et al [111,151], which could be programmed to change the magnetic field around the sample cell in order to control the dispersion of the magnetic sorbent through the sample.…”