On-line preconcentration and speciation of arsenic by flow injection hydride generation atomic absorption spectrophotometry

Determination of As(III) and total inorganic As in water samples using an on-line solid phase extraction and flow injection hydride generation atomic absorption spectrometry

“…In groundwater, As(III) and As(V) live dominantly in oxoanion forms with As(V) as H 2 AsO 4 − and HAsO 4 2− and As(III) as the neutral form HAsO 2 [2,23]. The different first acid dissociation constants (pK a ) of H 3 AsO 4 and HAsO 2 are 2.3 and 9.3, respectively, and allow the separation of As(III) and As(V) by means of ion-exchange mechanisms at the usual pH range of groundwater [24].…”

Non-chromatographic hydride generation atomic spectrometric techniques for the speciation analysis of arsenic, antimony, selenium, and tellurium in water samples—a review

“…Online pre-concentration of As(III) on activated alumina and total As after prereduction with L-cysteine was also reported [161]. Simultaneous online pre-concentration using an anion-exchange column was reported by Narcise et al [45], in which, the column is selective to As(V) at neutral pH and total As at pH > 12. Interference from methylated species was removed by cation exchange before selective adsorption.…”

Miniaturization of environmental chemical assays in flowing systems: The lab-on-a-valve approach vis-à-vis lab-on-a-chip microfluidic devices

“…As to on-column extraction schemes for hydride-forming species, post-column analyte chemical derivatization for evolving of gaseous species is a must [ 81 ]. And the on-line hyphenation of reversed-phase SPE with HPLC for monitoring of trace level concentration of organic pollutants needs dilution of the alcoholic eluate with aqueous solutions to prevent the broadening of the injection band along the analytical column [ 82 ].…”