Facile preparation of multifunctional uniform magnetic microspheres for T1-T2 dual modal magnetic resonance and optical imaging

• Published in: Colloids and surfaces, B, Biointerfaces B, Biointerfaces, 2016-08, Vol.144, p.344-354
• Main Authors: Zhang, Li, Liang, Shuang, Liu, Ruiqing, Yuan, Tianmeng, Zhang, Shulai, Xu, Zushun, Xu, Haibo
• Format: Article
• Language: English
• Subjects: Animals; HeLa Cells; Humans; Hydrodynamics; Liver - pathology; Luminescence; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Magnetics; Microspheres; Molecular imaging; Optical Imaging - methods; Particle Size; Rats, Sprague-Dawley; Relaxivity; Spectroscopy, Fourier Transform Infrared; Temperature; X-Ray Diffraction
• ISSN: 0927-7765; 1873-4367
• DOI: 10.1016/j.colsurfb.2016.04.014

[Display omitted] •A facile method using emulsifier-free emulsion polymerization was proposed.•In vitro, in vivo T1 and T2-weighted MRI and luminescence performance were studied.•Samples can be captured by spleen and liver, exhibiting excellent red luminescence.•Posses high resolution rate of histologic structure and sensitive detection. Molecular imaging is of significant importance for early detection and diagnosis of cancer. Herein, a novel core-shell magnetic microsphere for dual modal magnetic resonance imaging (MRI) and optical imaging was produced by one-pot emulsifier-free emulsion polymerization, which could provide high resolution rate of histologic structure information and realize high sensitive detection at the same time. The synthesized magnetic microspheres composed of cores containing oleic acid (OA) and sodium undecylenate (NaUA) modified Fe3O4 nanoparticles and styrene (St), Glycidyl methacrylate (GMA), and polymerizable lanthanide complexes (Gd(AA)3Phen and Eu(AA)3Phen) polymerized on the surface for outer shells. Fluorescence spectra show characteristic emission peaks from Eu3+ at 590nm and 615nm and vivid red fluorescence luminescence can be observed by 2-photon confocal scanning laser microscopy (CLSM). In vitro cytotoxicity tests based on the MTT assay demonstrate good cytocompatibility, the composites have longitudinal relaxivity value (r1) of 8.39mM−1s−1 and also have transverse relaxivity value (r2) of 71.18mM−1s−1 at clinical 3.0 T MR scanner. In vitro and in vivo MRI studies exhibit high signal enhancement on both T1- and T2-weighted MR images. These fascinating multifunctional properties suggest that the polymer microspheres have large clinical potential as multi-modal MRI/optical probes.