Determination of domoic acid in shellfish by high performance liquid chromatography-tandem mass spectrometry in the central-north sea areas of Fujian Province

In recent years,red tide disasters occur frequently in coastal areas of China,and poisoning incidents caused by eating shellfish occur from time to time.In this study,the conditions for determination of domoic acid(DA)by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)were investigated and verified.The results showed as follows:1)The linear range of DA was 0.5~25.0 μg/L,the limit of quantitation was 5 μg/kg,the average recoveries were 68.7%~92.4%,the intra-day relative standard deviation was 5.4%~8.4%(n=6),and the inter-day relative standard deviation was 3.9%~5.1%(n=6);2)The method was used to detect DA in main cultured mollusks in the central and northern waters of Fujian Province from 2020 to 2021.(1)DA was detected in 27 samples of 136 shellfish samples,with a detection rate of 19.9%.Among them,the detection rate in Lianjiang County of Fuzhou City,Fuding City of Ningde City and Putian City Bei'an District was higher,reaching 40% or more.(2)From April to June 2021,the overall detection rate showed an increasing trend(0%~41.5%).(3)Among 136 samples,DA was mainly detected in clams,oyster and mussel with the detection rate ranging from 13.6% to 35.7%.Abalone and scallop were not detected.This method had the advantages of rapid,high efficiency,high sensitivity and high accuracy,and was suitable for the daily detection and monitoring of domoic acid in shellfish,which was of great significance for strengthening the risk control of shellfish.