|Background: I received my B.S. in Chemistry in May of 1999 from Muhlenberg College in Allentown, Pennsylvania. I then left the beloved east coast to attend the University of Michigan in September of 1999. I am also a die hard sports fan that loves to watch Allen Iverson and Donovan McNabb lead the Sixers and Eagles to the promised land.
Current Research: My work has been focused on the development of magnesium sensitive PEBBLE nanosensors and their potential use for measuring intracellular magnesium fluxes. Although magneisum plays a key rolls in many biological functions, investigations on the role of intracellular free magnesium have been limited due to the lack of an effective sensing scheme that posesses the necessary selectivity over interfereing cations such as potasium, sodium, and most importantly calcium. This has lead to a large discrepency in the understanding of intracellular magnesium mechanisms compared to those for calcium. Without an effective means of measureing magnesium such processes will never be fully understood. We have been able to develop the first ratiometric magnesium sensor with an unprecedented selectivty over interfereing cations. This was done by encorporating a previously undiscovered magneisum sensitive fluorescent dye, coumarin 343 (C343), with a reference dye, texas red dextran. The resultant fluorescence emissions were used to construct calibration curves.
Calibration of magnesium selective PEBBLE sensors without background ions (diamond),in the presence of 1 mM Ca2+ (square), and in the presence of 1 mM Ca2+, 20 mM Na+, and 120 mM K+ (triangle). The samples were excited at 445 nm on the fluorometer and the emission spectra were collected. The peak ratio (FI/FR) is plotted against magnesium concentration.
Spectra of C343/TRD PEBBLEs at various Mg2+ concentrations. The C343 indicator peak at 485 nm increases as Mg2+ concentration is increased. The TRD reference peak remains constant throughout all Mg2+ concentrations.
Park EJ, Brasuel M, Behrend C, Philbert MA, and Kopelman R (2003). Ratiometric optical PEBBLE nanosensors for real-time magnesium ion concentrations inside viable cells. Analytical Chemistry, 75, 3784-3791.