This document proposes a new diagnostic technique using magnetic nanoparticles (mNPs) and gold nanoparticles (AuNPs) to rapidly detect biomarkers for diseases like malaria, HIV, and sepsis. The technique uses a microfluidic device with channels at different pH levels to cause the nanoparticles to aggregate and deaggregate based on the presence of target biomarkers. This allows the sample to be run through a test strip containing antibodies to provide a positive or negative result. The innovation combines nanoparticle techniques with microfluidics and immunoassay test strips. The significance is that it aims to provide better rapid diagnostics than existing methods like microscopy or PCR that require specialized equipment or settings. Anticipated problems include ensuring proper nanoparticle behavior at different pH levels

1. Magnetic and Gold
Nanoparticle Interactions
for Rapid Diagnostics
ALBERT NGUYEN, CHENKAI LU, COLLIN WATERTON JR., SNIGDHA
KANUPARTHY

2. Specific Aims
• Cheap and easy to use/ minimal training
• Ensure aggregation between mNP-AuNP-
copolymer complex
• Effective in detecting malaria, HIV, Sepsis
biomarkers

3. Malaria Worldwide
Malaria inpatient deaths by country
Still remains a problem
in developing nations
Problem with
diagnostics
Specifically, a need for
more diagnostics that
do not require a
lab/are rapid
Undiagnosed malaria
could lead to serious
consequences

4. HIV Worldwide
Incidence of HIV Worldwide
Burden of HIV borne
most by nations in
Africa
Developing nations
may not have access to
resources to rapidly
detect and diagnose
HIV/AIDS
Undiagnosed HIV/AIDS
can lead to further
complications

5. Sepsis Worldwide
1
• Afflicts 18 million people worldwide per year
2
• Incidence of sepsis has doubled in the past ten years
3
• If left unrecognized and untreated, has the possibility to
progress to septic shock (50%)

6. Laboratory Resources/Microscopy
Incidence of microscopic tests in areas with malaria
Although diagnostics are
occurring in areas with
malaria, the rate of these
laboratory tests are not
high enough
Laboratory diagnosis may
not coincide with the
patient receiving
information
Examination of microscopy
requires skilled healthcare
professionals

7. Chosen Labs
Yager:
• Microfluidics
• Immunoassays
• Point-of-care diagnostics
• Global health
Stayton:
• Nanomedicine
• Nanotechnology
• Molecular engineering

8. Design (Nanoparticles)
mNPs and Au-NPs bound to pH-
responsive polymer
• Low pH causes particles to aggregate
Au-NP polymers bound to
targeting antibody

9. Design (Microfluidic Device)
Two channels: low pH and high pH
Minimal diffusion across interface
◦ Low Reynolds #
1. Incubate sample with NPs
2. Add to low pH channel; aggregation
3. Magnetophoresis into high pH channel
4. Deaggregation so runs along channel

10. Design (Diagnostic Test Strip)
Run purified sample over test strip
Test strip contains antibody test line and control line

11. Innovation
• Previous approaches have utilized the NP techniques we incorporate in our device
• Combining two approaches to create a novel diagnostic system
• Microfluidic channels with solutions with low Reynolds number
• Using a nitrocellulose test strip and chemistries of NP and antibodies to detect
presence and concentration of targeted biomarker

12. Significance
Blood film
microscopy: high
quality
microscope,
trained personnel
PCR:
contaminations,
controlled
temperature
setting
Better than standard malaria diagnosis (blood film microscopy, PCR)

13. Anticipated Problems
1 • NP’s don’t aggregate/deaggregate in initial pH levels
2 • NP size issues based on pH changes with new complex
3
• New complex may need a stronger magnet than initially
proposed
4
• Purification percentages may not be high enough initially
with new complex
5
• Fabrication issues
• Leaking
• Issues with CAD transfer to fabrication device