Design of a Fluorescent Capillary Flow Immunosensor with Increased Sensitivity

1
Design of a Fluorescent Capillary Flow
Immunosensor with Increased Sensitivity

• Katrina Schweiker
• PI Greg Zimmerli
• Biosciences and Technology Branch
• 15 July 2005

2
Acknowledgements

• My Family
• George Makhatadze
• Ann Marie Daniel
• Greg Zimmerli
• Nicole, Mike, and Marius
• NASA Academy
• PA Space Grant

3
Overview

• Background
• Objectives
• Work Accomplished
• Work to be Completed
• The Big Picture
• Other Interesting Information

4
Background Definitions

• Gram Negative Bacteria
• E. coli

• Gram Positive Bacteria
• S. aureus

Both images from http//pathmicro.med.sc.edu/f
ox/cell_envelope.htm
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Background Definitions

• Antigen
• Epitope

Epitope
http//pathmicro.med.sc.edu/fox/cell_envelope.htm
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Background Definitions

• Antibody
• How does it differ from a protein?
• Polyclonal vs. Monoclonal

http//www.accessexcellence.org/RC/VL/GG/antiBD_mo
l.html
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Background Basic Technique

• In the 1990s Ligler, et al. developed the
  capillary flow immunosensor
• Based on ELISA
• Presence of antigen detected by fluorescence
  microscopy

http//users.rcn.com/jkimball.ma.ultranet/BiologyP
ages/E/Elisa.html
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Project Objectives

• Decrease the size of the sensor to 1 cm
• Need to reduce the length dependence of the
  sensitivity of the biosensor
• Increase the sensitivity
• CPG increases surface to volume ratio
• Quantum dots
• Colloidal gold

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Work Completed

• Design of apparatus
• Wire stoppers
• Cleaned Equipment
• Capillary Tube
• CPG
• Sialinization

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Work Completed

• Design of stage for microscope

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Future Work

• Create stretched glass apparatus
• Pattern CPG with anti-E. coli antibodies
• Decrease the autofluorescence of the CPG in the
  FITC spectrum
• Use a red fluorophore (phycoerythrin) next time,
  very little autofluorescence seen in this region
• Run the assay

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The Big Picture
http//www.nasa.gov/centers/glenn/events/vcjan05_p
lanetnews.html
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The Big Picture
Original Credit The Mars Society taken from
http//www.astronomie.de/bibliothek/interview/tart
er/
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The Big Picture
Original Credit NASA JSC taken from
www.bu.edu/bridge/archive/ 2004/12-03/fraser.html
http//ares.jsc.nasa.gov/HumanExplore/Exploration/
EXLibrary/images/Pics/MarsScenario1/08Ascent.gif
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The Big Picture
www.imagineeringezine.com/ e-zine/mars.html
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Fun Facts

• The labs bread and butter
• How microgravity affects gene expression
• Effects of shear stress on gene expression
• Imaging with the fluorescence microscope

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Summary

• Biology is cool
• Biosensors rock
• I hope to continue work in this area after grad
  school
• Applications are endless
• It would be great if Glenn could get more
  involved in biological research
• Health issues related to space travel is an
  enormous field

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Questions?