title: Clearance Pathways and Tumor Targeting of Imaging Nanoparticles.
abstract: A basic understanding of how imaging nanoparticles are removed from the normal organs/tissues but retained in the tumors is important for their future clinical applications in early cancer diagnosis and therapy. In this review, we discuss current understandings of clearance pathways and tumor targeting of small-molecule- and inorganic-nanoparticle-based imaging probes with an emphasis on molecular nanoprobes, a class of inorganic nanoprobes that can escape reticuloendothelial system (RES) uptake and be rapidly eliminated from the normal tissues/organs via kidneys but can still passively target the tumor with high efficiency through the enhanced permeability permeability and retention (EPR) effect. The impact of nanoparticle design (size, shape, and surface chemistry) on their excretion, pharmacokinetics, and passive tumor targeting were quantitatively discussed. Synergetic integration of effective renal clearance and EPR effect offers a promising pathway to design low-toxicity and high-contrast-enhancement imaging nanoparticles that could meet with the clinical translational requirements of regulatory agencies.
authors.affiliation: Department of Chemistry, The University of Texas at Dallas, 800 West Campbell Road, Richardson, Texas 75080, United States.
authors.forename: Mengxiao
authors.initials: M
authors.lastname: Yu
authors.affiliation: Department of Chemistry, The University of Texas at Dallas, 800 West Campbell Road, Richardson, Texas 75080, United States.
authors.forename: Jie
authors.initials: J
authors.lastname: Zheng
mesh_terms: D000818:Animals; D003952:Diagnostic Imaging / Q000379:methods; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry / Q000378:metabolism*; D009369:Neoplasms / Q000175:diagnosis*; D065667:Renal Elimination
keywords: cancer diagnosis; clinical translation; enhanced permeability and retention (EPR) effect; imaging nanoparticles; molecular nanoprobes; renal clearance; reticuloendothelial system (RES); tumor targeting