Isolation of Ligands of Trace Metals from Plant Samples by Immobilized Metal Affinity Chromatography

Abstract

Isolation of ligands of trace elements from plants by affinity chromatography with a metal immobilised on iminodiacetate resin has been investigated. To simulate various types of bioligands the following compounds were tested: phytic acid, peptides containing Cys and peptides containing Asp. Optimal conditions allowing isolation of the peptides with good efficiency comprise the use of Ga³⁺ ion, sample adsorption at pH = 4 and elution of the compounds by 0.3 mol/l NH₃. Phytic acid was bound too tightly and was not eluted. The procedure was used for purification of extracts of rye flour. The purified sample is suitable for analysis by MALDI-MS.

Keywords:

• Affinity chromatography
• Speciation
• Trace elements

The financial supports of the Grant Agency of Czech Republic (project no. 525=07=0903) and of the Ministry of Education, Youth and Sports of the Czech Republic (project no. MSM 6046137307) are gratefully acknowledged.