 Assistant Chemistry Professors David Mascotti and Mark Waner – along with
numerous other instructors and students – will use the $35,000 Photon counting
spectrofluorometer to
delve into the fundamental structure of matter. Dr. Mascotti said, “At least
five laboratories, including first year honors chemistry,” will benefit from the
new acquisition, the result of a Special Award in Chemistry from the Henry
Dreyfus Foundation. As its simplified name implies, the fluorometer measures fluorescence
of materials that, when excited by the instrument’s high intensity lamp, give
off a light of their own. Those photons are detected by using a photomultiplier
tube or PMT. The measurement reveals a lot about the target molecule such as its
structure, whether it is interacting with another molecule, and its orientation
with respect to molecules around it. For example, if one molecule absorbs the
highly energetic light photons, that energy can be transferred to a second
molecule which will produce yet another color of light. The efficiency of that
transfer can be used to help determine distance between molecules. “Because
this is such a sweet device,” Mascotti said, pointing to the unique design of
having two independently-controlled PMT's, “we can measure both
the first and second transfer.” He likened the transfer of energy to the handoff
of a baton between two relay runners who must be in just the right proximity to
each other, an analogy appreciated by Dr. Waner ‘91,
who ran track for JCU as an undergraduate. |