ORGN 405 |
| Matthew F. L. Parker, Clifford B. Murphy, Kristyn Pluchino, Thomas Noriega, and Wayne E. Jones Jr.. Department of Chemisty, Institute for Materials Research, and Center for Research on Environmental Systems, State University of New York, Vestal Parkway East, Binghamton, NY 13902 |
| It has been shown in the past that phenyleneethynylene-thiopheneethynylene polymers (PPETE) with oligopyridine pendant groups behave as highly sensitive chemosensors for cationic Lewis acid analytes. The enhanced chemosensory behavior is primarily due to electronic communication that occurs between receptor sites along the conjugated polymer backbone. We have developed an energy transfer based mathematical model, which describes this behavior. In order to test the role of receptor spacing on this communication, we have designed a series of PPETE polymers in which the receptor is present at every other monomer unit and also at every fourth, sixth, and eighth monomer unit. This was accomplished by employing a molecular design approach in which a third thiophene monomer free of any receptor unit is systematically incorporated. This new polymer series have absorption maximums ranging from 430 to 446 nm and emission maximums ranging from 474 to 508 nm, both of which exhibit a blue shift as the receptor loading decreases. Experiments show incomplete quenching occurring for all but the original PPETE polymer. These results provide insight into how these polymers behave and interact with the analyte including suggestions for improving polymer structure that should result in enhanced sensitivity and/or selectivity. |
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Materials, Devices, and Switches
8:00 AM-12:00 PM, Wednesday, March 31, 2004 Anaheim Convention Center -- 303A, Oral
Division of Organic Chemistry |