Soret peak

A Soret Peak is an intense peak in the blue wavelength region of the visible spectrum. The term is commonly used in absorption spectroscopy, corresponding to a wavelength of maximum absorption. The "soret peak" is used to describe the absorption of vividly pigmented heme-containing moieties, such as various cytochromes. For example, the cytochromes P450, a diverse class of monooxygenase enzymes, exhibit a soret peak at 450nm in their reduced form when saturated with carbon monoxide.