Abstract: Objective To propose a method for determination of tetrodotoxin（TTX） in human blood, urine and liver by liquid chromatography with tandem mass spectrometry（LC-MS/MS）. Methods Solid phase extraction is used after the samples are precipitated, then the samples will be analyzed by LC-MS/MS. Results The limits of detection were 2 ng/mL in blood and urine and 4 ng/g in liver for TTX respectively, the linear correlation coefficients were not less than 0.997 3, both of the intra-day and inter-day precisions were less than 12.80%, the recoveries for all kinds of specimens were more than 47.2%. Conclusion This method is efficient, sensitive and accurate and was successfully validated for implementation in forensic toxicological analysis.

Key words: forensic toxicology, tetrodotoxin, solid phase extraction, liquid chromatography-tandem mass spectrometry