The binding of CNA35 contrast agents to collagen fibrils

CryoTEM demonstrates that a CNA35-bearing liposomal MRI contrast agent selectively binds to poorly assembled collagen type I as opposed to well-assembled collagen fibrils, whereas monomeric CNA35 binds to all forms of collagen. It is shown that upon conjugation to liposomes and micelles CNA35 loses its ability to dissociate ordered collagen fibrils and thereby to create its own binding sites.