A Portable Immunoassay Platform for Multiplexed Detection of Biotoxins in Clinical and Environmental Samples

Journal Article · Wed Dec 31 23:00:00 EST 2014 · Sandia journal manuscript; Not yet accepted for publication

OSTI ID:1427244

Koh, Chung-Yan ^[1]; Piccini, Matthew Ernest ^[2]; Schaff, Ulrich Y. ^[3]; Stanker, Larry H. ^[4]; Cheng, Luisa W. ^[4]; Ravichandran, Easwaran ^[5]; Singh, Bal-Ram ^[5]; Sommer, Greg J. ^[3]; Singh, Anup K. ^[1]

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1. Sandia National Lab. (SNL-CA), Livermore, CA (United States)
2. Sandia National Lab. (SNL-CA), Livermore, CA (United States); Cepheid, Sunnyvale, CA (United States)
3. Sandia National Lab. (SNL-CA), Livermore, CA (United States); Sandstone Diagnostics, Livermore, CA (United States)
4. US Dept. of Agriculture, Albany, CA (United States). Western Regional Research Center, Foodborne Contaminants Research Unit
5. Univ. of Massachusetts, Dartmouth, MA (United States)

Multiple cases of attempted bioterrorism events using biotoxins have highlighted the urgent need for tools capable of rapid screening of suspect samples in the field (e.g., mailroom and public events). We present a portable microfluidic device capable of analyzing environmental (e.g., white powder), food (e.g., milk) and clinical (e.g., blood) samples for multiplexed detection of biotoxins. The device is rapid (<15-30 min sample-to-answer), sensitive (< 0.08 pg/mL detection limit for botulinum toxin), multiplexed (up to 64 parallel assays) and capable of analyzing small volume samples (< 20 μL total sample input). The immunoassay approach (SpinDx) is based on binding of toxins in a sample to antibody-laden capture particles followed by sedimentation of particles through a density-media in a microfluidic disk and quantification using a laser-induced fluorescence detector. A direct, blinded comparison with a gold standard ELISA revealed a 5-fold more sensitive detection limit for botulinum toxin while requiring 250-fold less sample volume and a 30 minute assay time with a near unity correlation. A key advantage of the technique is its compatibility with a variety of sample matrices with no additional sample preparation required. Ultrasensitive quantification has been demonstrated from direct analysis of multiple clinical, environmental and food samples, including white powder, whole blood, saliva, salad dressing, whole milk, peanut butter, half and half, honey, and canned meat. We believe that this device can met an urgent need in screening both potentially exposed people as well as suspicious samples in mail-rooms, airports, public sporting venues and emergency rooms. The general-purpose immunodiagnostics device can also find applications in screening of infectious and systemic diseases or serve as a lab device for conducting rapid immunoassays.

• Research Organization: Sandia National Laboratories (SNL-CA), Livermore, CA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); National Institutes of Health (NIH)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 1427244
• Report Number(s): SAND--2015-0079J; 558359
• Journal Information: Sandia journal manuscript; Not yet accepted for publication, Journal Name: Sandia journal manuscript; Not yet accepted for publication; ISSN 9999-0014
• Publisher: Sandia
• Country of Publication: United States
• Language: English