For instance, Belfiore et al. quantitatively estimated the amount of targeting moieties (specifically, plasminogen activator inhibitor-2 (PAI-2) and trastuzumab (TZ, Herceptin®) targeting cancer cell surface biomarkers) on functionalized liposomes [39], showing how this experimental/analytical approach can be applied for the characterization of a multifunctional drug delivery system. Here, SERPINB2 is linked to cancer.