Determination of biogenic amines in food by automated pre-column derivatization with 2-naphthyloxycarbonyl chloride (NOC-Cl)

The fluorogenic reagent 2-naphthyloxycarbonyl chloride (NOC-Cl) has been used for the automated precolumn derivatization of biogenic amines (BAs) at ambient followed by liquid-chromatographic separation of the derivatives formed. For optimized derivatization samples in 0.5 M berate buffer (pH 9.0) were derivatized with 5 mM NOC-Cl in acetonitrile (MeCN) for 3 minutes. Excess of reagent was scavenged by addition of 20 mM glycine in water. For HPLC a Superspher(R) RP-18e column and gradient elution using 0.1 M sodium acetate buffer (pH 4.4) and MeCN were used. The NOC-derivatives were detected by fluorescence at an emission wavelength of 335 nm at an excitation wavelength of 274 nm. This method allows the detection of BAs (2-phenylethylamine, putrescine, histamine, cadaverine, tyramine, spermidine, spermine) found in food and beverages (fruit juices, wines, various vinegars, fermented cabbage juice, and salmon). Detection limit of BAs are approximately 49-113 mu g kg(-1) with the exception of histamine (747 mu g kg(-1)) (injected amounts: 18-41 pg histamine 267 pg), at a signal-to-noise ratio of 3:1. The limits of determination are approximately 82-189 mu g kg(-1) (histamine 1245 mu g kg(-1)) at a signal-to-noise ratio of 5:1. The correlation coefficients of linearity are 0.9910-0.9976. Recoveries from different matrices range from 65 to 109%, depending on the sample investigated.