Polyurethane modified screen – printed electrode for the electrochemical detection of histamine in fish

Histamine needs to be determined because of its toxicity. Histamine is commonly determined using chromatography, where not only that the instrument is expensive, the process is very tedious and require an expert. A sensor was developed using palm-based polyurethane as an electro-sensor substrate. Palm-based polyurethane (PU) was produced via condensation polymerization between palm kernel oil-based monoester polyol (PKOp) and 4,4'- diphenylmethane diisocyanate (MDI). PU offers high porosity and capability to attach onto screen–printed electrode (SPE) sturdily without being disintegrated. PU–SPE adsorbed histamine onto its pores, before being oxidized. The oxidation process was detected using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Histamine was oxidized electrochemically at +0.31 V (vs. Ag/AgCl, 1 mol·L^-1, pH 7.5). Differential pulse voltemmetric approach were used in order to get a satisfactory response, thus the histamine concentration was made in the range from 1 × 10^-4 to 1 mmol·L^-1. A good sensitivity of 0.1 mmol·L^-1 was attained with 3.07 % during intraday and 9.55 % during interday. The detection and quantification limits of histamine acquired at 0.17 mmol·L^-1 and 0.53 mmol·L^-1, respectively. A wide variety of interfering compounds were also examined in order to establish their effect, if any, on the determination of histamine at the PU modified electrode. The sensor showed an excellent anti – interference property towards the other amines. The developed chemical sensor using PU – SPE has a good potential to determine histamine level in mackerel (Rastrelliger Brachysoma) owing to its simplicity and reproducibility.