柱后衍生高效液相色谱法测定水产品中河豚毒素含量

Determination of tetrodotoxin in aquatic products by post column derivation high performance liquid chromatography

采用柱后衍生高效液相色谱法检测水产品中的河豚毒素含量，选用河豚（Takifugu）和织纹螺（Nassarius）为主要研究对象，样品先由0．1％乙酸提取，经过C18固相萃取柱净化。以庚烷磺酸钠为离子对试剂，应用反相离子对液相色谱分离河豚毒素，采用在线柱后衍生系统，在110℃高温和4mol·L^-1 NaOH强碱条件下，将河豚毒素衍生化成具有荧光特性的C9碱，荧光检测器定量检测。河豚毒素在5～1600ng范围内呈良好的线性相关，相关系数r=0．9997；1、2、8μg·g^-1，3个浓度水平添加样，日内和日间的回收率为80．9％～91．2％、相对标准偏差为1．93％～5．57％；方法定量限为1μg·g^-1；从添加样色谱图上看，河豚毒素目标峰附近没有干扰峰，定性准确性好。采用柱后衍生高效液相色谱法与小鼠生物法检测同一阳性河豚样，检测结果一致性好。实验结果表明，柱后衍生高效液相色谱法适用于水产品中河豚毒素的检测。

Detection of tetrodotoxin（TTX）in aquatic products is a hot topic of research in food security field. Although the mouse bioassay is the current standard method with high sensitivity, its quality and quantification are poor. Detecting TTX by high perfonnanc.e liquid chromatography （HPLC） can improve quality and quantification. In China, the detector of the popular HPLC method is UV detector, its sensitivity and quality can＇t satisfy the food security standard, This article is researching determination of TTX in aquatic products by post column derivation HPLC. The separation characteristic of HPLC and fluorescence detector with selectivity and high sensitivity effectively improve sensitivity, quality and quantification, which make this method satisfy the food security standard. Takifugu and Nassarius were selected as the main research objects. Sample was extracted with 0.1% acetic acid, and then purified with C18 solid-phase extraction cartridge. TTX was separated by reverse phase ion-pair liquid chromatography, of which ion-pair reagent was heptanesulfonic acid sodium salt, then heated with 4 mol·L^-1 NaOH at 110℃ in on-line derivation system. It was converted to C9-base with fluorescence characteristic, quantified by fluorescence detector. Good linearity was observed： the linear range was 5 - 1 600 ng and linear relationship r = 0.9997. For the 1, 2, 8μg·g^-1 spiked samples, within-day and day-to-day recoveries were 80.9% -91.2 %, RSDs were 1.93 % - 5.57 %, and the limitation of quantification were 1 μg·g^-1 This method was good quality because of no interference peak near the TTX target peak in the chromatogram of spiked sample. When a poisonous Takifugu was detected by post column derivatization HPLC and mouse bioassay simultaneously, the results of the two methods were consistent. From the results of above, detection of TTX in aquatic products by post column derivation HPLC is feasible.