Fluorometric microbore amino acid analyzer: the construction of an inexpensive, highly sensitive instrument using o-phthalaldehyde as a detection agent.

The construction of a highly sensitive microbore amino acid analyzer is described. It is based on a standard column chromatographic separation technique with fluorometric detection utilizing o-phthalaldehyde. This analyzer has several desirable features: low column chromatographic pressure, high sensitivity, and easy maintenance. Good precision at a level of 10 pmol is obtained and as little as 0.2 μg protein has been hydrolyzed for composition analysis. It incorporates the use of the single-column method and constant molarity buffers to shorten the analysis time. It is fully automatic and capable of analyzing 130 samples within 7 days with attention required only for reloading 20 samples while the instrument is in operation. Amino acid composition determination based on the peak area and the peak height is discussed.