Imaging free zinc levels in vivo - What can be learned?

► Tracking the many forms of Zn in vivo is of prime importance. ► Deep-tissue labile or “free” aqueous Zn(II) in cells can be imaged in vivo, e.g., MRI. ► Rational Zn chelate design must consider KD, pZn, and the target microenvironment. ► Non-invasive Zn(II) tracking will need expertise in chemistry, biology, and medicine.