1. Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269
2. Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland 20892
3. Laboratory of Bioengineering and Physical Science, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland 20982
4. Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut 06032