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• Amino Acid Analyses
• Determination of other amino acids
°Semi  quantitative  determination
°quantitative  determination  GC-FID
°quantitative  determination  GC-MS
• Determination of optical Isomers
• Sequencing and molecular weight
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Semi quantitative determination 
(Order code: A445, SOP: A.0.6.)

1. histidine is not determined.
2. LOD is about 0.3% for Ala, Val, Gly, Thr, Ile, Pro, Leu, Ser, Asp, Met, Phe, Glu, Tyr, Lys, Arg and Trp, for Cys 2%

The results are area % of the sum of all identified amino acids. 2 results are possible:

• If no amino acid is found: Other amino acids are not determined.
  (Limit of detection <0.3% for the following amino acids: Ala, Val, Gly, Thr, Ile, Pro, Leu, Ser, Asp, Met, Phe, Glu, Tyr, Lys, Arg und Trp; <2% for Cys).
• If amino acid area % >0.15% is found: the result is doubled and reported as <x.x%.

It is to pointed out that this is a half quantitative analysis, so that the error of the result might be high:

• The LOQ for Cys, Met and Trp can be influenced by the matrix without any indication.
• But also hydrophobic amino acids can be discriminated by matrix effects
• Known decomposition products ( primarily for amino acid derivatives ) might co-elute with amino acids so that determination is not possible.
• Unknown contaminations can coelute with amino acids and suggest high content of an amino acid because the used detector is able to detect all organic components. With this method verification is not possible.

The analysis  is available as an additional service only eg. in addition to determination of enantiomeric purity.