Mario Alpuche-Aviles
University of Nevada-Reno, NV·Chemistry
A nanoparticle is roughly a million times smaller than the period at the end of this sentence, and at that scale the behavior of the whole population can hide what individual particles do. Two projects here share one approach: shrink the electrode down to nanometer or micrometer dimensions so that electrical current can be measured from a single particle or a single molecular complex.
- Fields
Chemistry
Materials Science
Biomedical Engineering
- Topics
single-entity electrochemistry
single nanoparticle detection
ultramicroelectrodes
- Grants
- 2 known grants, through Aug 2027
What they work on
- Develop a redox-mediated electrochemical scheme that detects antibody-gold-nanoparticle conjugates at ultramicroelectrodes under 30 micrometers across, selecting redox mediator pairs using Marcus theory of electron transfer.
- Test antibody-antigen detection in biological samples, assessing selectivity, non-specific binding and particle aggregation, and using electron transfer through pinholes to overcome biofouling of the electrode.
- Use the distance dependence of electron transfer, seen as a time dependence of the measured current, to distinguish specific from non-specific antibody-antigen interactions, validating against conventional ensemble assays such as ELISA.
- Measure photocurrent from single TiO2 and CdSe nanoparticles attached to nanoelectrodes as a function of electrochemical potential and light intensity to determine how electronic structure and metal contact govern hole transfer rates.
- Disentangle electron-hole recombination, hole trapping at surface defects and charge transfer to solution molecules by modeling single-nanoparticle photocurrent data with finite element simulations.
- Fabricate electrodes with nanometer dimensions and advance electrochemical instrumentation to improve the sensitivity of single-entity measurements.
More about the research
One project applies that idea to detecting biomolecules for medical diagnosis; the other uses it to follow light-driven chemistry on semiconductor surfaces. Both involve building the electrodes and instruments needed to make such small currents measurable.
Why it matters
Detecting antibody-antigen binding down to a single nanoparticle-bioconjugate could allow disease markers to be measured rapidly with minimal supplies and simple instrumentation, potentially identifying infection or disease before symptoms appear and informing treatment and isolation decisions. Separately, understanding how light-generated charges move across a single nanoparticle surface could inform better ways of converting sunlight into electricity and chemical fuels.
Known grants
From NIH and NSF research grants. Labs often have other funding we can't see.
Closest labs
Lior Sepunaru
University of California-Santa Barbara, CA·Chemistry
Develop a nanoscale electrochemical method to record the electronic response of individual enzymes during catalysis, revealing how single redox enzymes fluctuate in activity at the molecular level.
Vignesh Sundaresan
University of Mississippi, MS·Chemistry·Early-career
Fabricate monolithic nanopore electrode arrays with precisely defined pore size and interconnectivity to test how nanoscale confinement and mass transport govern the efficiency and product selectivity of hydrogen evolution and carbon dioxide reduction.
Dorsa Parviz
Arizona State University Campus Immersion, AZ·Chemistry·Early-career
Synthesize mixed-metal oxides with controlled composition gradients, defects and surface terminations to create tunable nanoscale electrostatic landscapes, and map them with surface-potential measurements.
The school
University of Nevada-Reno: 11 labs on PI Pages, $194M a year on research, 186 research doctorates a year.
Reach out
A start for your email. Fill in the brackets.