Amino acids

In humans proteins are made of 20 different proteogenic amino acids. Alpha-amino acids consist of a carboxyl- and an amino group linked by a carbon atom. They differ in the rest, which is linked to the carbon atom. The rest could be of acidic, basic or hydrophobic nature. At physiological pH value amino acids are zwitter ionic. The pKa value depends on the rest. Humans are only able to produce 11 out of the 20 proteogenic amino acids. Nine amino acids must be taken by nutrition. Proteins with these essential amino acids are named complete proteins. They are abundant in beef, fish, eggs and milk. Incomplete proteins are included in leaf vegetables, leguminous plants and cereals.

Beside the 20 proteogenic amino acids other amino acids with biological function are known. These rare amino acids are built by specific modifications of complete proteins. They act as neurotransmitters, metabolic intermediates or toxins.

The ImmuChrom LCMSMS-application for 30 amino acids makes it possible to determine them in an easy, fast and precise method. The kit includes all reagents in ready to use form for preparation and separation of the samples with exception of the column (IC4500rp) and the controls (IC4500ko). Both can be supplied by ImmuChrom GmbH.

Beside the complete testkit it is possible to order all components separately. Please request our single component pricelist.

Principle of the method

For the determination of the amino acids a precipitation step, which removes high molecular substances is performed first. After centrifugation the supernatant is injected into the HPLC system.
The HPLC separation is performed by an isocratic method at 20-25° C with a HPLC-column (IC4500rp). Chromatograms are detected by an MSMS-detector (AB-Sciex API4000). The separation takes 15 minutes for each run depending on the column used. Results are quantified by the delivered calibrator and calculated by the “internal standard-method” by integration of the peak areas or heights.