title: Real-time monitoring of magnetic drug targeting using fibered confocal fluorescence microscopy.
abstract: Magnetic drug targeting has been proposed as means of concentrating therapeutic agents at a target site and the success of this approach has been demonstrated in a number of studies. However, the behavior of magnetic carriers in blood vessels and tumor microcirculation still remains unclear. In this work, we utilized polymeric magnetic nanocapsules (m-NCs) for magnetic targeting in tumors and dynamically visualized them within blood vessels and tumor tissues before, during and after magnetic field exposure using fibered confocal fluorescence microscopy (FCFM). Our results suggested that the distribution of m-NCs within tumor vasculature changed dramatically, but in a reversible way, upon application and removal of a magnetic field. The m-NCs were concentrated and stayed as clusters near a blood vessel wall when tumors were exposed to a magnetic field but without rupturing the blood vessel. The obtained FCFM images provided in vivo in situ microvascular observations of m-NCs upon magnetic targeting with high spatial resolution but minimally invasive surgical procedures. This proof-of-concept descriptive study in mice is envisaged to track and quantify nanoparticles in vivo in a non-invasive manner at microscopic resolution.
authors.affiliation: Institute of Pharmaceutical Science, Faculty of Life Sciences & Medicine, King's College London, SE1 9NH, UK.
authors.forename: Jie
authors.initials: J
authors.lastname: Bai
authors.affiliation: Institute of Pharmaceutical Science, Faculty of Life Sciences & Medicine, King's College London, SE1 9NH, UK.
authors.forename: Julie Tzu-Wen
authors.initials: JT
authors.lastname: Wang
authors.affiliation: Institute of Pharmaceutical Science, Faculty of Life Sciences & Medicine, King's College London, SE1 9NH, UK.
authors.forename: Kuo-Ching
authors.initials: KC
authors.lastname: Mei
authors.affiliation: School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
authors.forename: Wafa T
authors.initials: WT
authors.lastname: Al-Jamal
authors.affiliation: Institute of Pharmaceutical Science, Faculty of Life Sciences & Medicine, King's College London, SE1 9NH, UK. Electronic address: khuloud.al-jamal@kcl.ac.uk.
authors.forename: Khuloud T
authors.initials: KT
authors.lastname: Al-Jamal
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D016503:Drug Delivery Systems; D005260:Female; D060328:Magnetic Phenomena; D008807:Mice, Inbred BALB C; D018613:Microscopy, Confocal; D053769:Nanocapsules / Q000008:administration & dosage* / Q000737:chemistry / Q000627:therapeutic use; D009369:Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D011108:Polymers / Q000008:administration & dosage / Q000737:chemistry / Q000627:therapeutic use; D047368:Tumor Burden / Q000187:drug effects
chemical_list: D053769:Nanocapsules; D011108:Polymers
keywords: Cellvizio®; Magnetic drug targeting; Nanomedicine; Superparamagnetic iron oxide nanoparticles (SPIONs); Tumor