title: Long-term prevalence of NIRF-labeled magnetic nanoparticles for the diagnostic and intraoperative imaging of inflammation.
abstract: Inflammation is a very common disease worldwide. In severe cases, surgery is often the method of choice. Today, there is a general need for the implementation of image-based guidance methodologies for reliable target resection. We investigated new near infrared fluorescence (NIRF)-nanoparticles (NPs) as a simple but effective bimodal magnetic resonance imaging (MRI) and optical contrast agent for diagnosis and intraoperative imaging of inflammation. Physicochemical analysis revealed that these NPs were highly fluorescent with similar characteristics like unlabeled NPs (hydrodynamic diameter about 130 nm and zeta potential about -10 mV). NP-uptake and NIR-dye labeling was biocompatible to macrophages (no impact on cellular ATP and reactive oxygen species production). These cells could successfully be tracked with MRI and NIRF-optical imaging. I.v. injection of fluorescent NPs into mice led to highly specific T2-weighted signal of edema due to uptake by phagocytic cells and subsequent migration to the site of inflammation. NIRF signals of the edema region were well detectable for up to 4 weeks, underlining the potential of the NPs for systematic planning and flexible time scheduling in intraoperative applications. NPs were degraded over a time period of 12 weeks, which was not altered due to inflammation. Redistribution of iron might be primarily due to inflammation and not to the presence of NPs per se in a concentration suitable for imaging. Our findings highlight the potential of the NPs to be used as a suitable tool for pre- and intraoperative imaging of inflammation.
authors: a Department of Experimental Radiology , Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena , Jena , Germany .
authors: Jenny
authors: J
authors: Domey
authors: b Chemicell GmbH , Berlin , Germany .
authors: Christian
authors: C
authors: Bergemann
authors: c Institute of Clinical Chemistry and Laboratory Diagnostics, Jena University Hospital - Friedrich Schiller University Jena , Jena , Germany , and.
authors: Sibylle
authors: S
authors: Bremer-Streck
authors: d Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena , Jena , Germany.
authors: Ines
authors: I
authors: Krumbein
authors: d Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena , Jena , Germany.
authors: Jürgen R
authors: JR
authors: Reichenbach
authors: a Department of Experimental Radiology , Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena , Jena , Germany .
authors: Ulf
authors: U
authors: Teichgräber
authors: a Department of Experimental Radiology , Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena , Jena , Germany .
authors: Ingrid
authors: I
authors: Hilger
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003287:Contrast Media; D007249:Inflammation / Q000175:diagnosis*; D008264:Macrophages / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000737:chemistry; D008297:Male; D051379:Mice; D057054:Molecular Imaging / Q000379:methods*; D010586:Phagocytes / Q000378:metabolism; D013050:Spectrometry, Fluorescence / Q000379:methods*
chemical_list: D003287:Contrast Media; D058185:Magnetite Nanoparticles
keywords: Biocompatibility; MRI; biodistribution; degradation; optical imaging