Bombarding Surfaces to Understand Chemistry

Winograd Bombarding Surfaces to Understand Chemistry

Winograd’s chemical imaging technique proves long-theorized existence of metabolons in cells.

Winograd joined the Penn State Chemistry Department in 1979, working on imaging capabilities in secondary ion mass spectroscopy across multiple areas of materials and exploring ion beams of argon, gold, bismuth, metal clusters, C60 (bucky-balls), and of late, giant atomic and molecular clusters. For example, Winograd used SIMS methods to understand a wide variety of materials problems, including molecular adsorption and description kinetics on various metals that drive important catalytic reactions. Major insights into the experimental observations that realized these successes were made via collaboration with his spouse and chemistry department colleague Barbara Garrison, using molecular dynamic and first principles approaches to understand the details of the ion beam and secondary ion generation.

However, perhaps the greatest of his many impacts was his biochemistry work. Winograd investigated chemical imaging

at a submicron scale in single biological cells, using time-of-flight secondary ion mass spectrometry (ToF-SIMS). This has opened new opportunities in the understanding of biochemistry in the cell. Winograd’s group surprised the biological community by being able to image phospholipid cell membranes and detect low concentrations of other chemical species, such as drugs and cholesterol.

Most recently, the Winograd group directly detected enzyme clusters, known as metabolons, which are different enzymes that cluster to effectively drive a complex chemical reaction. These metabolons had been predicted for over 40 years, but the Winograd group used SIMS imaging to “see” them and prove their existence. This enables the tracking of metabolic reactions at the subcellular level and will spark exciting new pharmaceutical research, which potentially could include a new class of cancer therapeutics.