title: Detection of human exposure to saxitoxin and neosaxitoxin in urine by online-solid phase extraction-liquid chromatography-tandem mass spectrometry.
abstract: 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.
authors: Centers for Disease Control and Prevention, 4770 Buford Highway, MS F44, Atlanta, GA 30341, USA.
authors: William A
authors: WA
authors: Bragg
authors: Centers for Disease Control and Prevention, 4770 Buford Highway, MS F44, Atlanta, GA 30341, USA.
authors: Sharon W
authors: SW
authors: Lemire
authors: ORISE, Centers for Disease Control and Prevention, National Center for Environmental Health, Division of Laboratory Sciences, Atlanta, GA 30341, USA.
authors: Rebecca M
authors: RM
authors: Coleman
authors: Centers for Disease Control and Prevention, 4770 Buford Highway, MS F44, Atlanta, GA 30341, USA. Electronic address: eph3@cdc.gov.
authors: Elizabeth I
authors: EI
authors: Hamelin
authors: Centers for Disease Control and Prevention, 4770 Buford Highway, MS F44, Atlanta, GA 30341, USA.
authors: Rudolph C
authors: RC
authors: Johnson
mesh_terms: D053000:Analytic Sample Preparation Methods; D057205:Automation, Laboratory; D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D057230:Limit of Detection; D009498:Neurotoxins / Q000737:chemistry / Q000633:toxicity / Q000652:urine*; D009587:Nitrogen Isotopes; D015203:Reproducibility of Results; D012530:Saxitoxin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000633:toxicity / Q000652:urine*; D012680:Sensitivity and Specificity; D057096:Shellfish Poisoning / Q000175:diagnosis / Q000209:etiology / Q000652:urine*; D052616:Solid Phase Extraction; D053719:Tandem Mass Spectrometry; D066007:Toxicokinetics
chemical_list: D009498:Neurotoxins; D009587:Nitrogen Isotopes; D012530:Saxitoxin; C034902:neosaxitoxin
keywords: LC-MS/MS; Marine toxins; Neosaxitoxin; Online SPE; Saxitoxin