Optical Immunoassay for Snake bite Diagnosis
Snake BitesVenom is in concentrations of 0.2-200 ng/mL
3 venomous categories:
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Market Research
Snakebite Diagnosis
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CompetitionCSL Diagnostics: Snake Venom Detection Kit based on the EIA test for use in Australia ($65/test)
- Relative insensitivity- High levels of false positive
results- Cross-reactivity- Use venom from bite site
swab, but does not indicate systemic envenoming
Need StatementPractitioners need an easy, reliable, effective, and cheap way to diagnose snake bites out in the field and in clinics with basic facilities.
Optical ImmunoassayOptical detection is an easy way to detect which antivenom will work!
OIA versus ELISAFor high sensitivity and specificity
Microfluidic Channels- Insert 50uL test sample (blood/plasma/urine/wound exudates/blister
fluid/tissue homogenate) at the center of the chip- Use a heating coil to incubate the sample for 10 minutes- Use centrifugal force spinning the disc to move the sample through several
microfluidic channels:- Rinse sample with washing buffer - Drying the sample with air- Mixing with botinylated antibody solution (50uL)- Incubate for 10 minutes, additional washing and drying cycle- HRP-avidin conjugate (50uL) mixed in and incubated for 5 minutes- Washed and dried again- Substrate solution (50uL) applied to the center of the chip, incubated for 5 minutes- Observe changes in the color spots and intensity for venom specification and concentration
Device Design Principles
Point-of-care Device
Bubble Gate Valves- Provide any necessary heating to buffers
and to speed up antibody binding- Selectively and sequentially switch valves
on/off using an external electronic system
MEMS Fabrication Process
Thanks for your attention!
Any questions?