Stable fluorimetric detection of histamine using o-phthaldialdehyde derivatizing agent and surfactants in water-acetonitrile mixed solvent

Abstract

A new analytical method for the rapid detection of histamine (HA) in beverages using fluorescence detection has been devised. It is primarily based on the use of o-phthalaldehyde (OPA) as a derivatizing agent. This unstable complex has been efficiently stabilized by addition of surfactants. The physicochemical variables that influence the sensitivity of the method and the fluorescence properties of the complex species in surfactant solutions have been optimized. Different surfactants were checked: the anionic sodium dodecyl sulfate, the cationic hexadecyltrimethylammonium chloride and the nonionic tricosa(ethylene glycol)dodecyl ether C12E23. All surfactants stabilize the HA:OPA complex for long times. C12E23 provides excellent stability to the complex and higher fluorescence emission, allowing robust analysis conditions. Linear calibration curves allowing effective histamine determination and low limits of detection and quantification were established and the characteristics of the analysis method was validated. The correlation coefficient for histamine detection by fluorescence was 0.9978. The detection and quantification limits for histamine were 0.576 and 1.92 mg∙L−1, respectively.