1. Department of Chemical and Physical Sciences, Cedar Crest College, 100 College Drive, Allentown, Pennsylvania 18104-6196, United States
2. Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8312, United States
3. Department of Chemistry and Biochemistry and International Forensic Research Institute, Florida International University, University Park, Miami, Florida 33199, United States