1. Microfluidic Bacterial Detection
for Resource-Limited Areas
Mallory Williams & Willy Leineweber
Santa Clara Micro/Nanosystems Laboratory
SCHOOL OF ENGINEERING

2. Outline:
• Define the problem
• Proposed device solution
• How the device works
• Results and progress
• Future work
• Scope of impact
• Conclusions and acknowledgements

3. SCHOOL OF ENGINEERING
http://lightmeetsdark.com/tag/charity-water
3.4 million deaths yearly

4. Global Health Impact of Bacteria-
Contaminated Water
10% of global health burden
SCHOOL OF ENGINEERING
Source: WHO

5. ASSURED Standard
SCHOOL OF ENGINEERING
A
Affordable
S
Sensitive
S
Specific
U
User
Friendly
R
Rapid &
Robust
E
Equipment
Free
D
Deliverable to
End Users
Conventional
Electrochemical
Indicator Method
Our Device
Source: WHO

6. Proposed Design

7. Device Overview
SCHOOL OF ENGINEERING
1. Collect sample
and load onto
device. 2. Unfold device
to see result
3. Take picture to
interpret result
Leineweber, W., Williams, M., et al. Towards bacterial pathogen detection using
paper-based microfluidic device integrated with a mobile platform. IEEE Healthcare
Innovation Point-of-Care Technologies Conference. Seattle, WA. Oct 2014.

8. ASSURED
Device
Paper-Based Microfluidic Detection
• Cellulose
• Wax Printing
SCHOOL OF ENGINEERING

9. Device Use

10. Assay Design
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11. Assay Steps
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Steps Involved for Device
• Load sample
• Lyse bacterial cells
• Capture the targeted
bacterial RNA
• Produce signal
• Analyze results
TEM of Streotococcus
pyogenes cell lysis
Source: Daniel Nelson, UMD

12. Zirconia-coated cellulose
Immobilized
“Capture” DNA
strand
Bacterial RNA
“Target” strand
DNA/AuNP
“Detection”
strand
Enhancement
Nucleic Acid Assay Design

13. 22uM 11uM 5.5uM 2.8uM 1.4uM Control
Results – Binding Verification
10nM 100pM 1pM Control
Fluorescent Imaging of Target Strand
Fluorescent Imaging of Capture Strand

14. Results – Assay Response
SCHOOL OF ENGINEERING
Concentration of Bacterial RNA
Leineweber, W., Williams, M., et al. Towards bacterial pathogen detection using
paper-based microfluidic device integrated with a mobile platform. IEEE Healthcare
Innovation Point-of-Care Technologies Conference. Seattle, WA. Oct 2014.

15. Results – Analysis by Mobile Application
Leineweber, W., Williams, M., et al. Towards bacterial pathogen detection using
paper-based microfluidic device integrated with a mobile platform. IEEE Healthcare
Innovation Point-of-Care Technologies Conference. Seattle, WA. Oct 2014.

16. Leineweber, W., Williams, M., et al. Towards bacterial pathogen detection using
paper-based microfluidic device integrated with a mobile platform. IEEE Healthcare
Innovation Point-of-Care Technologies Conference. Seattle, WA. Oct 2014.

17. v
vvvv v
vv
vvvvvv
vv
vvv
Load
Sample
Lyse Cell
Bacterial RNA binds
with DNA/AuNP
Capture Pad
Future Directions
Signal Enhancement

18. Potential Impact
Inexpensive
device
Equal access
to technology
Improve
awareness of
preventable
health threats
Uphold the
dignity of the
human person

19. Conclusions
• Bacterial pathogens in
water sourcesProblem
• Affordable pathogen
detection deviceSolution
• Improved health in
resource-limited areasImpact

20. Acknowledgements
• University Honors Program for awarding us the
Hayes Grant
• Miller Center for Social Entrepreneurship for
awarding us the Roelandts Grant
• Dr. Korin Wheeler for her expertise and advice
• Dr. Allia Griffin for her valuable input
• Our wonderful advisor Dr. Ashley Kim for her
continued support and inspiration