Ultrasensitive flow-injection electrochemical method for determination of histamine in tuna fish samples

Histamine is a potentially hazardous compound and one of the major concerns in food chemistry. High amount of histamine may be found in food as a consequence of the use of poor quality raw materials, contamination and inappropriate conditions during food processing and storage. A novel method for the determination of histamine in flow-injection systems has been developed for use in seafood quality inspection and food quality control laboratories. The developed technique is very simple, precise, accurate, time saving and economic as compared to all of the previously reported methods. The effects of various parameters on the sensitivity of the method were investigated. The best performance was obtained with the conditions, pH value of 2.0, and sweep rate value of 40 V/s, accumulation potential of 900 mV and accumulation time of 0.4 s. In this work, we introduce a special computer based numerical method, for calculation of the analyte signal and noise reduction. The electrode response was calculated based on partial and total charge exchanges at the electrode surface after subtracting the background current from noise. The waveform potential consisting of potential steps for cleaning and accumulation of analyte, and potential ramp was applied on an Au disk microelectrode (with a radius of 12.5 μm). The method was linear over the concentration range of 1.1–5555 pg/ml (r = 0.998) with a limit of detection and quantification 0.35 and 1.16 pg/ml, respectively.