Article

Applications of amino acid derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate. Analysis of feed grains, intravenous solutions and glycoproteins.

Millipore Corporation, Milford, MA 01757.
Journal of Chromatography (impact factor: 4.53). 03/1994; 661(1-2):25-34. DOI:10.1016/0021-9673(93)E0821-B pp.25-34
Source: PubMed

ABSTRACT Primary and secondary amines are rapidly labelled by 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate to form highly fluorescent asymmetric urea derivatives which are readily amenable to analysis by liquid chromatography. Derivatization consists of a simple, one-step procedure, and the resulting labelled amines can be analyzed without further cleanup. The adducts are extremely stable with no discernible loss in response after storage for one week at room temperature, making the reagent an ideal candidate for pre-column amino acid analysis. Chromatographic methods for protein hydrolysates have been developed for the analysis of samples containing many unusual amino acids including a number of cysteine derivatives, collagen hydrolysates containing hydroxyproline and hydroxylysine, performic acid oxidized samples and glycoprotein hydrolysates containing glucosamine and galactosamine. Samples with potentially interfering matrix components such as hydrolyzed feed grains and intravenous solutions are readily analyzed and are quantified with average per cent relative standard deviations in the 1-2% range. Comparative data on these samples are in good agreement with either ion-exchange amino acid analysis or label information.

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Keywords

cent relative standard deviations
 
collagen hydrolysates
 
Comparative data
 
galactosamine
 
glycoprotein hydrolysates
 
good agreement
 
hydrolyzed feed grains
 
ideal candidate
 
intravenous solutions
 
ion-exchange amino acid analysis
 
label information
 
matrix components
 
one-step procedure
 
performic acid oxidized samples
 
pre-column amino acid analysis
 
protein hydrolysates
 
resulting labelled amines
 
room temperature
 
secondary amines
 
unusual amino acids
 

S A Cohen