title: Sequential injection determination of orthophosphate as ion associate of 12-molybdophosphate with Astra Phloxine.
abstract: A simple and fast reaction between 12-molybdophosphate heteropoly anion and the polymethine dye Astra Phloxine was used for the development of a new SIA method for the determination of orthophosphate. The suggested method has higher sensitivity and a broader calibration range than existing SIA methods. It can be used to detect phosphate in the range from 0.2 to 10 μmol L(-1) with a detection limit of 0.1 μmol L(-1) and an acceptable throughput of 20 samples h(-1). The comparably low molybdate (5.6 mmol L(-1)) and dye (0.1 mmol L(-1)) concentrations led to an improvement in the stability of the base line. Inter-day reproducibility was better than 5%, while the intra-day RSD was in the range 0.8-3.5%. The method was used for the analysis of natural water samples and phosphorus-containing chemicals having a low content of orthophosphate.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Oles Gonchar Dnipropetrovsk National University, Gagarina 72, Dnipropetrovsk 49010, Ukraine.
authors.forename: Svitlana V
authors.initials: SV
authors.lastname: Khlyntseva
authors.forename: Andriy B
authors.initials: AB
authors.lastname: Vishnikin
authors.forename: Mohammed K E A
authors.initials: MK
authors.lastname: Al-Shwaiyat
authors.forename: Hana
authors.initials: H
authors.lastname: Sklenářová
authors.forename: Petr
authors.initials: P
authors.lastname: Solich
authors.forename: Yaroslav R
authors.initials: YR
authors.lastname: Bazel
authors.forename: Vasil
authors.initials: V
authors.lastname: Andruch