Selective fluorimetric method for the determination of histamine in seafood samples based on the concept of zone fluidics

In the present article we report our results on the development of a selective automated method for the determination of histamine in seafood using the concept of zone fluidics. The method is based on the sequential on-line reaction of the analyte with o-phthalaldehyde in the absence of a nucleophilic reagent, followed by acidification. The careful selection of the chemical and instrumental variables enabled the determination of the analyte with adequate sensitivity at the low micromolar level and with specificity against other biogenic amines and amino acids such as histidine. The LOD was 0.05 μmol L⁻¹ (0.6 mg kg⁻¹) and linearity was obeyed in the range of 0.5–15 μmol L⁻¹ (5.5–170 mg kg⁻¹). The proposed method offers a satisfactory sampling rate of 15 h⁻¹ and adequate accuracy and precision for the analysis of seafood products after minimum sample preparation and without employing a separation technique.