1. • BASi C3 static cell
• Working macro electrodes (glassy carbon and platinum both tested)
• Platinum counter electrode and Ag/AgCl reference
• Cyclic Voltammetry (CV) and Square Wave Voltammetry (SWV) both tested
• For space, best graphs displayed.
• Low levels of beta-carotene correlate with risk of myocardial infarction
• No point of care detection method exists
• A point of care sensor for beta-carotene is needed
• Serum levels of beta-carotene are on the nM scale
Electrochemical Detection of Antioxidants Using Surface Modified Electrodes
Garrett Thompson1 and Jeffrey M. Halpern2
University of New Hampshire: 1MCBS and 2Chemical Engineering
Scheme 1: Beta-carotene interacting
with a bare glassy carbon electrode
Figure 1: CV of a beta-carotene serial dilution
Figure 2: Calibration curve of the above (Fig 1.) beta-carotene serial dilution
Scheme 2: a) BCD modified platinum electrode
b) with methylene blue c) with beta-carotene
Scheme 3: Tween 20 removes
methylene blue from BCD
Figure 3: SWV of beta-carotene serial dilution in a Tween/PBS solution with a beta-
cyclodextrin/methylene blue modified electrode.
Figure 4: Calibration curve comparing a beta-carotene serial dilution (Fig. 3) and
tween 20 control using beta-cyclodextrin/methylene blue modified electrode.
Scheme 4: Decylaniline modified glassy carbon
electrode interacting with beta-cyclodextrin
Figure 5: SWV of a beta-carotene serial dilution with a decylaniline modified glassy
carbon electrode.
Figure 6: Calibration curve of the above (Fig 5.) beta-carotene serial dilution
Introduction Methods
Unmodified Glassy Carbon Electrode
Beta-cyclodextrin Methylene Blue Modified
Platinum Electrode
Decylaniline Modified Glassy Carbon
Electrode
Conclusion Acknowledgements
• Beta-carotene is electrochemically active
• Sensitivity at a bare electrode surface is not high enough to detect beta-carotene in serum
• Cyclodextrin methylene blue modified electrode approach is not specific to beta-carotene
• Preliminary data on decylaniline modification shows positive results
• Further testing of decylaniline modification must be run
• Decylaniline modified electrode will be tested with other antioxidants
• Additional aniline modifications will be tested
• Honors Program
• Halpern Lab members: Mariah Arral, Alexis Mack,
Elnaz Mohammadi, Micaela Schones, and Sabrina Marnoto
• Hamel Center for Undergraduate Research
• College of Engineering and Physical Sciences
• Department of Chemical Engineering
• Department of Molecular, Cellular, and Biomedical Sciences