Speciation analysis of manganese in tea samples using flame atomic absorption spectrometry after cloud point extraction

Yalçın S., Filik H., Apak R.

JOURNAL OF ANALYTICAL CHEMISTRY, vol.67, no.1, pp.47-55, 2012 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 67 Issue: 1
  • Publication Date: 2012
  • Doi Number: 10.1134/s1061934812010194
  • Journal Name: JOURNAL OF ANALYTICAL CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.47-55
  • Istanbul University Affiliated: Yes

Abstract

The speciation of Mn(II) in tea infusion was studied using cloud point extraction (CPE). In tea infusion, the flavonoid-bound Mn(II) was extracted at pH 5.0 using Triton X-100 (TX-100), the remaining free aquated Mn(II) and weakly-complexed Mn(II) in solution were both chelated with 8-hydroxyquinoline (HOx) and CPE-preconcentrated with TX-100. The enriched analyte was determined by flame AAS. The optimal concentrations for CPE of 0.02 ppm Mn were as follows: TX-100, 0.2% (v/v); HOx, 1.0 x 10(-4) M; NaCl, 1.0% (w/v). LOD was 1.9 mu g/L with a preconcentration factor of 10-20. The method was validated using a standard XAD-resin separation procedure and applied to synthetic seawater and CRM samples.