Transcript NSF Nuggets 2010: Silica-Polypeptide Composite Particles (and Worms)

Silica-Polypeptide Composite Particles (and Worms)
Paul S. Russo (Louisiana State University),
We make small (1/1000th of a
millimeter) particles, each composed of a
solid, glass-like core and magnetic
“nougat”, all coated by a soft, protein-like
shell. The particles may someday be
used to carry anticancer drugs to tumor
sites, guided by interaction of the
magnetic nougat with an applied
magnetic field. A sample particle appears
as the top image.
This year, progress has been made in
preparing these materials by a new,
more efficient chemistry, and we have
located collaborators familiar with
anticancer therapy. But this report
focuses on what happens when things
go wrong. The lower figure shows a
“microworm”, an unwanted byproduct.
What is the best approach when things
go wrong?
DMR-Award #1005707
Nice,
round
particle
Undesirable
microworm
Silica-Polypeptide Composite Particles (and Worms)
Paul S. Russo (Louisiana State University),
A radio wave has a wavelength of 100 m and the speed
of light is 3 x 108 m/sec. What is its frequency (per sec)?
a) 30,000 b) 3 x 1010 c) 3.0 x 106 d) 3.33 x 10-5
What is the charge on the atoms or ions pictured
below (from left to right)?
a) +1, 0, -2 b) 0, +1, +2 c) -1, 0, +2 d) +1, 0, -1
Two questions from the Chemical Educational Foundation’s “You be the Chemist “ Challenge (Grades 5-8).
2010 National Challengers in Philadelphia, PA , June 18.
Louisiana State Champ, Jaylun Brumfield (seated, 2nd
from left) will join the laboratory of colleague John Pojman
this fall. The 2009 National Champion works afternoons in
our lab, supported by NSF, and the 2009 State runner-up
will join colleague Donghui Zhang ‘s group this fall.
DMR-Award #1005707
Technical Broader Impact. The “bad”
microworms in Slide #1 can be isolated
from the “good” spheres, but could we do
more? Nature provides a clue. The worms
resemble magnetotactic bacteria , microorganisms which know north from south
and use their end-attached tails to swim
accordingly. We will try to attach
polypeptide tails to the worms; although
they will not swim, we may succeed at
guiding the particles as they move through
solution under an applied field. NSF is
training young scientists to convert
hardship to opportunity. As mom
instructed, given lemons, make lemonade.
Non-technical Broader Impact. Work
with the Chemical Educational Foundation
continues. Shown are sample questions
the contestants must answer orally and
without calculators during CEF’s “You be
the Chemist Challenge” (a national quiz
bowl competition). We help to write and vet
these questions and promote the program
in Louisiana.