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ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Foodborne Toxin Detection and Prevention Research » Research » Publications at this Location » Publication #280331

Title: Centrifugal microfluidic platform for ultrasensitive detection of Botulinum Toxin

item KOH, CHUNG-YAN - Sandia National Laboratory
item SCHAFF, ULRICH - Sandia National Laboratory
item PICCINI, M - Sandia National Laboratory
item Stanker, Larry
item Cheng, Luisa
item RAVICHANDRAN, EASWARRAN - University Of Massachusetts
item SING, BAL-RAM - University Of Massachusetts
item SOMMER, GREG - Sandia National Laboratory
item SINGH, ANUP - Sandia National Laboratory

Submitted to: Analytical Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/17/2014
Publication Date: 12/18/2014
Citation: Koh, C., Schaff, U.Y., Piccini, M., Stanker, L.H., Cheng, L.W., Ravichandran, E., Sing, B., Sommer, G.J., Singh, A.K. 2014. Centrifugal microfluidic platform for ultrasensitive detection of Botulinum Toxin. Analytical Chemistry. 87(2):922-928. DOI: 10.1021/ac504054u.

Interpretive Summary: Botulism is a serious, often fatal neuroparalytic disease in humans and animals caused by a protein toxin (botulinum toxin, BoNT) produced by the bacterium Clostridium botulinum. BoNT is considered the most toxic biological toxin known. Because of its high toxicity, the need for a long recovery period requiring extensive treatment, and the ease of producing BoNT,it is considered a class A bioterrorism agent. These same properties make the toxin difficult to study. In this report a rapid, ultra-sensitive assay for BoNT using a novel biosensor that purifies and measures the toxin in a single device. The availability of this assay will enhance our ability to monitor for toxin in food and provide enhanced public safety.

Technical Abstract: Botulinum neurotoxin – a global public health threat and category A bioterrorism agent - is the most toxic substance known and one of the most challenging toxins to detect due to its lethality at extremely low concentrations. Hence the live-mouse bioassay because of its superior sensitivity, remains the gold-standard despite its exceedingly high cost, need for specialized facilities and expertise, and time-consuming protocols. We have developed a simple, sample-to-answer microfluidic platform that vastly outperforms the antiquated live-mouse bioassay for botulinum neurotoxin serotype A (BoNT/A). The SpinDxTM platform employs a sedimentation-based centrifugal immunoassay and requires no sample preparation for clinical, food, and environmental samples. A blind, head-to-head comparison study of SpinDxTM versus the live-mouse bioassay demonstrates 100-fold improvement in sensitivity (limit of detection = 0.09 pg/mL), while achieving total sample-to-answer time of <30 minutes with 2-uL required volume of unprocessed sample. We further demonstrate BoNT/A quantification without any loss of sensitivity directly from the sera of intravenously-, orally-, and intranasally-intoxicated mice, as well as from untreated food samples including canned meat, carrot juice, peanut butter, and salad dressing with no additional sample preparation.