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Published on: July 14, 2017
Quantitation of saxitoxin in human urine using immunocapture extraction and LC-MS
William A Bragg1, Alaine Garrett2, Elizabeth I Hamelin1
1Emergency Response Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control & Prevention, Atlanta, GA, 30341 USA.
Aim:
An immunomagnetic capture protocol for use with LC-MS was developed for the quantitation of saxitoxin (STX) in human urine.
Materials & Methods:
This method uses monoclonal antibodies coupled to magnetic beads. STX was certified reference material grade from National Research Council, Canada. Analysis was carried out using LC-MS.
Results:
With an extraction efficiency of 80%, accuracy and precision of 93.0-100.2% and 5.3-12.6%, respectively, and a dynamic range of 1.00-100 ng/ml, the method is well suited to quantify STX exposures based on previously reported cases.
Conclusion:
Compared with our previously published protocols, this method has improved selectivity, a fivefold increase in sensitivity and uses only a third of the sample volume. This method can diagnose future toxin exposures and may complement the shellfish monitoring programs worldwide.
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