Gas chromatography of amino acids: Use of a fused-silica capillary column in the determination of plasma amino acids

✍ Scribed by Labadarios, D. ;Moodie, I. M. ;Burger, J. ;Shephard, G. S.

• Publisher: John Wiley and Sons
• Year: 1986
• Tongue: English
• Weight: 411 KB
• Volume: 9
• Category: Article
• ISSN: 0935-6304
• DOI: 10.1002/jhrc.1240091003

✦ Synopsis

A capillary chromatographic procedure using a fused silica column is described which can be used to quantitatively determine amino acids in plasma following the pre-chromatographic "clean-up" described in a recent paper [l]. In substituting this procedure for that involving a packed column, advantage has been taken of the greater resolving power to separate amino acids from background component peaks. lnorderto extend this advantage and provide a sound basis for quantitative analysis, the technique of cold on-column injection was employed. As a result, good precision of standard analysis was obtained with relative standard deviation (RSD) values for all amino acids of less than 4%. Application of the entire procedure to plasma samples yields RSD values of better than 10% for all amino acids with recoveries ranging from 72% to 104%. Simultaneous determination of plasma amino acid levels by gas chromatography (GC) using capillarycolumnsand by classical ion exchange (CIE) showed reasonable agreement. Statistical evaluation showed no significant difference between twelve amino acids. Values for the remaining two, namely, phenylalanine and histidine are significantly different (p< 0.005). Comparison of thevaluesobtained from GC capillary and packed columns reveals no significant difference between fourteen amino acids. Significant differences exist between results for phenylalanine and tyrosine (p < 0.001). It is concluded that there is good agreement betweendataobtained by GCcapillaryandCIEtechniquesand that differences between results for phenylalanine and histidine are method related.