Ellen Sletten

3:15 p.m. – Public research seminar, Taylor Auditorium
4:30 p.m. – Research proposal, A81

Exploiting Orthogonality in Chemical Biology and Materials Science

The development of functional group-specific, or orthogonal, chemistries is of long-standing interest to chemists and has facilitated the synthesis of highly complex molecules.  However, the demands for orthogonal chemistry are significantly greater when one moves from a reaction flask to a living organism or functional device.  In the first portion of this seminar, I will discuss covalent chemical reactions that can be rapidly performed on proteins, live cells and in living animals without disrupting the surrounding environment.  Reactions that meet these criteria have been termed “bioorthogonal” and I will focus on two transformations: Cu-free click chemistry between azides and cyclooctynes, and the ligation of quadricyclane and nickel bis(dithiolenes).  In the second part of the seminar, I will describe how non-covalent chemical orthogonality can be applied to develop solution-based fluorescent sensors.  The fluorous phase, a dense, non-polar phase that separates from organic and aqueous solutions, is used as a platform to create stable, yet dynamic, materials. Through the course of this work, an array of fluorescent perfluorocarbon nanoemulsions with different surface properties has been prepared.  The facile self-assembly of emulsions with defined functionality poises these materials to have far-reaching applications in sensing, in vivo imaging, and spray-on electronics.   with broad utility in chemical analysis, environmental monitoring, diagnosis of disease, and protection of public safety.