失忆性贝毒质谱测定与分析(英文)

Determination and analysis of amnesic shellfish poisoning by mass spectrometry

背景:失忆性贝毒属于海洋神经毒素,是一类具有神经兴奋的氨基酸类物质,其主要成分为软骨藻酸。贝类通过滤食毒藻,将软骨藻酸富集在体内,人类因食用被软骨藻类污染的贝类而中毒。目的:建立液相色谱/四极杆-行时间质谱联用技术对贝类样品中的软骨藻酸实施有效监控,以期提高贝类的食用安全性。设计:前瞻性自身对照实验。单位:上海检验检疫局动植物与食品检验检疫技术中心理化实验室。材料:MUS-1B贻贝组织标样[(36±1)μg软骨藻酸/g,批号MUS-1B0159]和软骨藻酸标准溶液(100mg/L,批号软骨藻类CS-1C352)购自NationalResearchCouncilofCanada(Halifax,Canada)。实际贻贝样品取自历年在东海爆发的赤潮海域收集得到的阳性贝类,空白样品购自市集。高效液相色谱仪(Waters2695)配有紫外检测器(Waters2487)和四极杆-飞行时间质谱仪(QUltima,Micromass)。方法:样品用甲醇-水(体积比为1∶1)提取,经SAX固相萃取柱净化后,用ZorbaxEclipseXDB-18柱(250×2.1mm,3.5μm)色谱分离,流动相为乙腈/水含0.05%甲酸,梯度淋洗,流速0.20mL/min。四极杆-飞行时间质谱选择电喷雾正离子模式,以[M+H]+作为前体离子进行飞行时间质谱扫描测定。主要观察指标:①检测限。②液相色谱/四极杆-飞行时间质谱法的准确度与精密度。

BACKGROUND:Amnesic shellfish poisoning(ASP) is caused by consumption of seafoo d contaminated by marine neurotoxins,mainly domoic acid(DA). OBJECTIVE:To ensure the safety of shellfish consumption by determining DA in s hellfish by means of liquid chromatography(LC) combined with quadrupole time of flight mass spectrometry(Q TOF MS). DESIGN:A self controlled prospective study SETTING:The experiment was carried out in the Center for Animal, Plant and Foo d Inspection and Quarantine,Shanghai Exit Entry Inspection and Quarantine Burea u. MATERIALS:MUS 1B,a nominal sample of homogenized mussel tissue(containing 36 ±1 μg DA per gram,Batch No.MUS 1B 0159) and the standard DA solution (100 mg/ L,Batch No.DACS 1C 352) were purchased from National Research Council of Canada (Halifax,Canada).Positive mussel samples were collected from the waters during the occurrence of red tide in China East Sea,and blank mussel samples were obtai ned from local seafood market.LC system (Waters 2695) combined with Q TOF MS(QU ltima,Micromass) and ultravilet(UV) detection(Waters 2487) was employed for anal ysis of ASP toxins. METHODS:The shellfish tissue samples were extracted with methanol water(1∶1, V/V) and cleansed with a SAX solid phase extraction cartridge.Separation was ca rried out on a Zorbax Eclipse XDB 18 column(250×2.1 mm,3.5 μm) with gradient elution of ACN H2O containing 0.05%formic acid at a flow rate of 0.20 mL per m inute.In a positive electrospray ionization DA was ionized effectively,and colli sion induced dissociation(CID) produced predominant characteristic ions+ allowing sensitive TOF MS detection. MAIN OUTCOME MEASURES:①Limit of quantification(LOQ);②Accuracy and precision of LC/Q TOF MS method. RESULTS:The average recoveries of DA spiked to tissue homogenates through the complete cleanse procedure ranged from 87.8%to 94.6%,and the relative standard deviations(RSD) ranged from 8.4%to 11.9%.The LOQ in the shellfish tissue was 0.1 μg/g. CONCLUSION:LC/Q TOF MS suits well the purpose of detecting and identifying AS P toxins in shellfish with high sensitivity and specificity,and may provide refe rence values for monitoring the safety of consumption of shellfish.