Miniemulsion Synthesis of Metal–Oxo Cluster Containing Copolymer Nanobeads

Abstract

Hybrid nanobeads containing either a manganese-oxo or manganese-iron-oxo cluster have been prepared via the miniemulsion polymerization technique. Two new ligand substituted oxo clusters, Mn(12)O(12)(VBA)(16)(H(2)O)(4) and Mn(8)Fe(4)O(12)(VBA)(16)(H(2)O)(4) (where VBA = 4-vinylbenzoate), have been prepared and characterized. Polymerization of the functionalized metal-oxo clusters with styrene under miniemulsion conditions produced monodispersed polymer nanoparticles as small as ~60 nm in diameter. The metal-oxo polymer nanobeads were fully characterized in terms of synthetic parameters, composition, structure, and magnetic properties.

Paramagnetic Clusters of Mn3(O2CCH3)6(Bpy)2 in Polyacrylamide Nanobeads as a New Design Approach to a T1–T2 Multimodal Magnetic Resonance Imaging Contrast Agent

“…Using direct miniemulsion polymerization conditions, we synthesized homogenous 50−80 nm beads of Mn 8 Fe 4 (VBA) 16 co-polymerized with styrene, to form Mn 8 Fe 4co-PS. 30 Polystyrene, a hydrophobic polymer, is often used as a noncovalent coating for nanobeads. Importantly, the r 1 for Mn 8 Fe 4 -co-PS increased to 3.37 mM −1 s −1 while the r 2 decreased to 11.2 mM −1 s −1 , making it possible for the nanobeads to support T 1 weighted imaging.…”

Paramagnetic Mn8Fe4-co-Polystyrene Nanobeads as a Potential T1–T2 Multimodal Magnetic Resonance Imaging Contrast Agent with In Vivo Studies

“…Miniemulsion polymerization was adapted from our previously reported synthesis of Mn 8 Fe 4 -co-PS. 5,6 The Mn 8 Fe 4 -co-PS-IO was generated by replacing the hexadecane hydrophobe with iso-octane, as described here.…”

“…Miniemulsion polymerization was adapted from our previously reported synthesis of Mn 8 Fe 4 - co -PS. , The Mn 8 Fe 4 - co -PS-IO was generated by replacing the hexadecane hydrophobe with iso -octane, as described here. Recrystallized Mn 8 Fe 4 VBA (0.1593 g, 0.0435 mmol) (see the Supporting Information for the synthesis) was dissolved in styrene (0.906 g, 8.7 mmol) and divinylbenzene (0.012 g, 0.087 mmol) in a small vial under stirring to which AIBN (0.0394 g, 0.24 mmol), Lumogen F Red 305 (0.002 g, 0.002 mmol), and iso -octane (0.0149 g, 0.13 mmol) were added as the hydrophobe.…”

“…Our pioneering cluster-nanocarrier system takes advantage of preformed discrete molecular clusters with magnetically coupled transition metals (Mn and Fe) that are then grafted within a polymer nanocarrier. − Polystyrene was chosen as the nanocarrier based on its established in vitro and in vivo stability and safety, which has led to its wide investigation for drug delivery . The size and monodispersity of pure polystyrene nanobeads are so finely controllable that they have been utilized as a model to investigate the role of size in nano-biointeractions .…”

Hybrid Materials Based on the Embedding of Organically Modified Transition Metal Oxoclusters or Polyoxometalates into Polymers for Functional Applications: A Review

“…In particular, either a manganese-oxo or manganese-iron-oxo cluster Mn 12 O 12 (VBA) 16 (H 2 O) 4 and Mn 8 Fe 4 O 12 (VBA) 16 (H 2 O) 4 (where VBA = 4-vinylbenzoate), were prepared and characterized. Polymerization of the functionalized metal oxoclusters with styrene, under miniemulsion conditions [200,201], produced monodispersed polymer nanoparticles endowed with magnetic properties for potential magnetic imaging applications [202,203]. …”