Bragg William A, Lemire Sharon W, Coleman Rebecca M, Hamelin Elizabeth I, Johnson Rudolph C
Centers for Disease Control and Prevention, 4770 Buford Highway, MS F44, Atlanta, GA 30341, USA.
ORISE, Centers for Disease Control and Prevention, National Center for Environmental Health, Division of Laboratory Sciences, Atlanta, GA 30341, USA.
Toxicon. 2015 Jun 1;99:118-24. doi: 10.1016/j.toxicon.2015.03.017. Epub 2015 Mar 27.
Saxitoxin (STX) and neosaxitoxin (NEO) are potent neurotoxins that cause paralytic shellfish poisoning (PSP). PSP typically occurs through the ingestion of bivalve shellfish that have consumed toxin producing dinoflagellates. Due to initial presentation of symptoms being nonspecific, a clinical measurement is needed to confirm exposure to these toxins. Our group has developed an online solid phase extraction hydrophilic interaction liquid chromatography (HILIC) method for the analysis of STX and NEO in human urine with tandem mass spectrometry. A unique feature of this online method is the incorporation of a new synthetic (15)N4-STX labeled internal standard used for quantitation. Manual sample preparation time was reduced by approximately 70% for 98 urine samples as compared to a previously reported method. The lowest reportable limit for STX was improved from 5.0 ng/mL to 1.01 ng/mL and from 10.0 ng/mL to 2.62 ng/mL for NEO. Three analysts validated the method with 20 calibration curves total over 30 days with precision and accuracy within ±15% for all QCs. This new online method rapidly identifies STX and NEO exposure with improved sensitivity, which can facilitate the work of public health authorities to confirm the cases of PSP, complementing the many shellfish monitoring programs worldwide.
石房蛤毒素（STX）和新石房蛤毒素（NEO）是强效神经毒素，可导致麻痹性贝类中毒（PSP）。PSP通常是通过食用摄食了产生毒素的甲藻的双壳贝类而发生的。由于最初的症状表现不具有特异性，因此需要进行临床检测来确认是否接触了这些毒素。我们团队开发了一种在线固相萃取亲水作用液相色谱法（HILIC），用于通过串联质谱分析人尿液中的STX和NEO。这种在线方法的一个独特之处是采用了一种新的合成的（15）N4-STX标记内标用于定量。与之前报道的方法相比，98份尿液样本的手工样品制备时间减少了约70%。STX的最低报告限从5.0 ng/mL提高到1.01 ng/mL，NEO的最低报告限从10.0 ng/mL提高到2.62 ng/mL。三位分析人员在30天内总共用20条校准曲线对该方法进行了验证，所有质量控制样品的精密度和准确度均在±15%以内。这种新的在线方法能够以更高的灵敏度快速识别STX和NEO暴露情况，有助于公共卫生当局确认PSP病例，对全球众多贝类监测项目起到补充作用。
