Carpenter Research Bio:
William (Memo) Carpenter got his first taste of research as an undergraduate at UC
Berkeley (2009-2013) working in the lab of Professor Rich Saykally to study ion
speciation at the air-water interface. William then pursued his PhD at the University of
Chicago (2014-2020) in the lab of Professor Andrei Tokmakoff, where he developed
two-dimensional infrared (2DIR) spectroscopy experiments to study the structures and
dynamics of the common but mysterious aqueous proton H+(aq). His experiments
uncovered direct spectroscopic fingerprints of proton hopping between water molecules
and connected these hops to the collective hydrogen-bonding dynamics of the solution.
Upon graduation, William began his postdoctoral fellowship in the lab of W.E. Moerner
at Stanford, monitoring individual biological nanocontainers in a solution-phase anti-
Brownian trap. These experiments simultaneously probed various chemical and
physical properties of these single objects, such as internal redox chemistry and single-
particle masses for improved models of the assembly and function of these objects.
William will open his lab in August 2024, incorporating advanced molecular
spectroscopy into single-particle observation for fundamental research on new
nanoparticles used for biomedical and sustainability science.

Research Summary:
Our group will focus on fundamental relationships between the chemical and physical
properties of nanoparticles made from biological building blocks. As these nanoparticles
are made of molecules like proteins or lipids, they are self-assembled by many weak
noncovalent interactions, but they ultimately form singular objects. This leads us to ask
many questions about their assembly and molecular behavior, such as:

 How do molecular contacts and chemical environment influence physical
properties like cargo loading and density?
 Conversely, how does the physical assembly affect access to internalized cargo
such as enzymes?
 What principles do biological nanocontainers use that we could apply to drug
delivery or generating specific molecules?
 How can we measure these effects on a benchtop microscope?

A key piece in studying these objects is that they can be highly heterogeneous in their
properties: each object is different in terms of aspects like their size, stoichiometry, and
molecular arrangement within the particle, which means that we need to observe these
various properties simultaneously on single members in the population. Our group will
be developing sensitive single-particle observation techniques such as anti-Brownian
trapping, single-molecule spectroscopy, and cryo-electron microscopy to determine
relationships between the various properties in these soft nanoparticle systems. These
methods will allow us to observe single objects with unprecedented detail and inspire
new strategies for designing next-generation biomolecular nanoparticles.

 

Publications:

A full list can be found on my Google Scholar Profile:

Selected publications prior to OSU:

WB Carpenter, AA Lavania, JS Borden, LM Oltrogge, D Perez, PD Dahlberg, DF Savage, and W.E. Moerner, “Ratiometric Sensing of Redox Environments Inside Individual Carboxysomes Trapped in Solution,” J Phys Chem Lett. 2022, 13, 4455.

AA Lavania, WB Carpenter, LM Oltrogge, D Perez, JB Turnsek, DF Savage, and W.E. Moerner, “Exploring masses and internal mass distributions of single carboxysomes in free solution using fluorescence and interferometric scattering in an anti-Brownian trap,” J Phys Chem B, 2022, 126, 8747.

B Dereka, Q Yu, NHC Lewis, W.B. Carpenter, JM Bowman, and A Tokmakoff, “Crossover from Hydrogen to Chemical Bonding,” Science, 2021, 371, 160. (Press release)

WB Carpenter, NHC. Lewis, JA Fournier, and A Tokmakoff, “Entropic Barriers in the Kinetics of Aqueous Proton Transfer,” J Chem Phys. 2019, 151, 034501.

JA Fournier, WB Carpenter, NHC Lewis, and A Tokmakoff, “Broadband 2D IR Spectroscopy Reveals Dominant Asymmetric H5O+2 Proton Hydration Structures in Acid Solutions,” Nature Chem. 2018, 10, 932 (Press release)

WB Carpenter, JA Fournier, NHC Lewis, and A Tokmakoff, “Picosecond Proton Transfer Kinetics in Water Revealed with Ultrafast IR Spectroscopy,” J Phys Chem B. 2018, 122, 2792.