title: Silica-F127 nanohybrid-encapsulated manganese oxide nanoparticles for optimized T1 magnetic resonance relaxivity.
abstract: To properly engineer MnO nanoparticles (MONPs) of high r1 relaxivity, a nanohybrid coating consisting of silica and F127 (PEO106PPO70PEO106) is designed to encapsulate MONPs. Achieved by an interfacial templating scheme, the nanohybrid encapsulating layer is highly permeable and hydrophilic to allow for an optimal access of water molecules to the encapsulated manganese oxide core. Hence, the efficacy of MONPs as MRI contrast agents is significantly improved, as demonstrated by an enhancement of the MR signal measured with a pre-clinical 7.0 T MRI scanner. The nanohybrid encapsulation strategy also confers high colloidal stability to the hydrophobic MONPs by the surface decoration of PEO chains and a small overall diameter (<100 nm) of the PEO-SiO2 nanohybrid-encapsulated MONPs (PEOMSNs). The PEOMSNs are not susceptible to Mn-ion leaching, and their biocompatibility is affirmed by a low toxicity profile. Moreover, these hybrid nanocapsules exhibit a nano-rattle structure, which would favor the facile loading of various therapeutic reagents for theranostic applications.
authors.affiliation: NUS Graduate School for Integrative Sciences and Engineering (NGS), National University of Singapore, 28 Medical Drive, 117456, Singapore. msewangj@nus.edu.sg.
authors.forename: Benedict You
authors.initials: BY
authors.lastname: Wei Hsu
authors.forename: Miao
authors.initials: M
authors.lastname: Wang
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Vimalan
authors.initials: V
authors.lastname: Vijayaragavan
authors.forename: Siew Yee
authors.initials: SY
authors.lastname: Wong
authors.forename: Alex
authors.initials: A
authors.lastname: Yuang-Chi Chang
authors.forename: Kishore Kumar
authors.initials: KK
authors.lastname: Bhakoo
authors.forename: Xu
authors.initials: X
authors.lastname: Li
authors.forename: John
authors.initials: J
authors.lastname: Wang
mesh_terms: D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003287:Contrast Media / Q000737:chemistry* / Q000633:toxicity; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008279:Magnetic Resonance Imaging; D017895:Manganese Compounds / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008823:Micelles; D010087:Oxides / Q000737:chemistry*; D011095:Polyethylenes / Q000737:chemistry*; D011126:Polypropylenes / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D003287:Contrast Media; D017895:Manganese Compounds; D008823:Micelles; D010087:Oxides; D011095:Polyethylenes; D011126:Polypropylenes; C027424:manganese oxide; D012822:Silicon Dioxide; C078661:UCON 50-HB-5100