The Synthesis and Use of Rotaxane Molecules as Transfer Agents for Ions

Abstract

By Alyssa Tobin, Chemistry

Advisor: David Smithrud

Presentation ID: 92

Abstract: Being able to selectively bind and transport varieties of particles to specific locations is an extremely useful strategy in areas such as targeting specific cells, such as cancer cells, and developing MRI contrast agents. Rotaxane molecules can selectively bind ions and act as this type of transport agent. We synthesized rotaxane molecules, specifically rotaxane-18-crown-6, in the laboratory in order to test its ability to transfer a variety of particles- in this case, metal cations. Different metal cations (positive ions) are transferred by these rotaxanes at different concentrations. To detect and measure cation concentrations, we need to use a sensitive instrument that can detect trace levels of ions. Inductively coupled plasma mass spectroscopy (ICP-MS) provides the necessary sensitivity to measure very dilute concentrations of elements in solution. We utilized ICP-MS to measure the levels of cation transfer to the rotaxane molecules synthesized in the lab. After analyzing transfers for calcium, sodium, and potassium cations to the rotaxane, we found that the calcium ion is transferred at the highest concentration.