James Penner–Hahn, Ph.D., is a Professor in the Department of Chemistry and Chair of the Biophysics Research Division at the University of Michigan. He received his B.S. in Chemistry from Purdue in 1979 and his Ph.D. in Chemistry from Stanford University in 1984, with a dissertation on structural characterization of the metal sites in plastocyanin and cytochrome P–450. He joined the staff of the Stanford Synchrotron Radiation Laboratory, where he worked with Professors Hodgson and Solomon on polarized x–ray absorption near–edge structure. He joined the faculty of the University of Michigan in 1985.

He is developing methods for characterizing the distribution and speciation of metal ions in biological samples. This emerging area of inorganic physiology includes both micrometer–scale imaging of metal distributions in biological tissues and nanometer–scale imaging of the subcellular distribution of metal ions.