Professor
Department of Chemistry and Biochemistry
University of Delaware
102 Lammot DuPont Laboratory
Newark DE 19716-2522
Email: mvj@udel.edu
Phone: (302) 831-8014
Fax: (302) 831-6335
Ph.D., Chemistry, University of Wisconsin, 1980
B.S., Chemistry, Bucknell University, 1976
Dr. Johnston and his research team use various combinations of lasers and mass spectrometry to study a variety of chemical problems. For example, his group uses matrix-assisted laser desorption ionization (MALDI) and electrospray ionization (ESI) to gently vaporize and ionize large biomolecules for accurate molecular mass determination. When combined with standard enzyme reactions, these methods can provide sequence information as well.
According to Dr. Johnston, there are no longer any apparent limitations to the size of a sample that can be handled by mass spectrometry. Even macromolecules in the 100 kD range, or viruses in the 50 MD range, can be characterized. Using the technology developed in his group and elsewhere, individual airborne particles and bacteria can be analyzed in real-time.
After earning his Ph.D. from the University of Wisconsin, Dr. Johnston served a post doctoral fellowship at Northwestern University. He then taught at the University of Colorado at Boulder until coming to the University of Delaware in 1990.