Mak's research focuses on the structural characterization of stable terminal states and unstable intermediates involved in the enzymatic cycles of heme proteins that play important roles in human physiology, as well as those that have potential for application to biotechnological processes. These goals are achieved using mainly resonance Raman (rR) spectroscopy, which has long been recognized as a remarkably effective probe of heme-containing enzymes. The coupling of rR spectroscopy with cryoradiolysis method, which involves γ-irradiation of the freeze-trapped dioxygen adducts, provides an effective method to generate, trap and structurally characterize otherwise elusive enzymatic intermediates
