An amperometric biosensor for the rapid assessment of histamine level in tiger prawn (Penaeus monodon) spoilage

Histamine could accumulate in seafood when bacteria spoilage commenced and caused histamine poisoning without altering the fish normal appearance and odor. Therefore, a histamine biosensor using immobilized enzyme diamine oxidase (DAO) has been developed for the rapid monitoring of the histamine levels in tiger prawn (Penaeus monodon). The histamine biosensor had a response time of <1 min and optimum pH of operation was 7.4 with reproducibility and repeatability (n = 5) of 4.87% and 5.26% relative standard deviations (RSD) respectively. Recoveries ranging from 93.11% to 100.58% were obtained for histamine spiked at levels from 5 to 20 ppm. The variation in histamine levels of some tiger prawn samples after a 5-h exposure at temperature of 30 °C ± 2 were studied using the histamine biosensor and the results were comparable to histamine levels determined by an HPLC method. The two methods showed a linear correlation with R2 = 0.9612 (Y = 0.9164x + 5.58). The limit of detection was 0.65 ppm of histamine, which is below the indicator level of 50 ppm established by USA FDA. The reusable biosensor is simple and can be used for direct histamine determination without further sample pretreatment, and is suitable for the routine analysis of histamine in tiger prawns to monitor spoilage.