I need to remove amino acids presents in water extracts of plants tissues because, binding to the FMOC-Cl, interfere with quantification of the other molecules.
Do you know a method for amino acids removal?
Dear Sir. Concerning your issue about the amino acids removal from water extract of plant leaves. The most perfect method for the determination of the amino acid composition of pure protein, feeds or biological fluids is still the ion exchange column chromatography (IEC). By the help of the lithium buffer system most of the problems on the field of free amino acid analysis of biological fluids can be solved. At IEC most contaminants move rapidly through the post-column system and are discarded before separation of amino acids begins, resulting in better performance. The time of the sample preparation is minimal compared to pre-column methods, and the detection (with ninhydrin or OPA) is chemically specific for amino acids. Nowadays a new off-line sample preparation method was introduced before analysis by anion-exchange chromatography and integrated amperometric detection, which eliminates carbohydrates from amino acid samples. The major problems remained the hydrolysis of the protein, the deproteinization of the biological fluids and the partial decomposition of methionine, cysteine and tryptophan during the sample preparation for analysis. At the moment the traditional IEC with postcolumn ninhydrin derivatization seems to be the best for both pure proteins and feeds and complex mixtures. I think the following below links may help you in your analysis:
http://www.acta.sapientia.ro/acta-alim/C1-1/alim1-1.pdf
http://www.gcu.edu.pk/FullTextJour/JNSM/2008/1%20Amino%20Acid%20analysis.pdf
Thanks