title: Preparation of Metalloporphyrin-Bound Superparamagnetic Silica Particles via "Click" Reaction.
abstract: A facile approach using click chemistry is demonstrated for immobilization of metalloporphyrins onto the surface of silica-coated iron oxide particles. Oleic-acid stabilized iron oxide nanocrystals were prepared by thermal decomposition of iron(III) acetylacetonate. Their crystallinity, morphology, and superparamagnetism were determined using X-ray diffraction, transmission electron microscopy, and a superconducting quantum interference device. Monodisperse core-shell particles were produced in the silica-coating of iron oxide via microemulsion synthesis. Surface modification of these particles was performed in two steps, which included the reaction of silica-coated iron oxide particles with 3-bromopropyltrichlorosilane, followed by azido-functionalization with sodium azide. Monoalkylated porphyrins were prepared using the Williamson ether synthesis of commercially available tetra(4-hydroxyphenyl) porphyrin with propargyl bromide in the presence of a base. (1)H NMR and matrix-assisted laser desorption ionization confirmed the identity of the compounds. The prepared monoalkyne porphyrins were zinc-metalated prior to their introduction to azide-functionalized, silica-coated iron oxide particles in the click reaction. X-ray photoelectron spectroscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy were used to characterize the surface chemistry after each step in the reaction. In addition, particle size was determined using dynamic light scattering and microscopy. The presented methodology is versatile and can be extended to other photoreactive systems, such as phthalocyanines and boron-dipyrromethane, which may lead to new materials for optical, photonic, and biological applications.
authors.affiliation: Department of Chemistry and Macromolecular Studies Group, Louisiana State University , Baton Rouge, Louisiana 70803, United States.|Department of Chemistry & Physics, University of St. Thomas , Houston, Texas 77006, United States.
authors.forename: Javoris V
authors.initials: JV
authors.lastname: Hollingsworth
authors.affiliation: Department of Chemistry and Macromolecular Studies Group, Louisiana State University , Baton Rouge, Louisiana 70803, United States.
authors.forename: N V S Dinesh K
authors.initials: NV
authors.lastname: Bhupathiraju
authors.affiliation: Dr. Anthony Volpe Research Center, American Dental Association Foundation , 100 Bureau Drive, Stop 8546, Gaithersburg, Maryland 20899, United States.
authors.forename: Jirun
authors.initials: J
authors.lastname: Sun
authors.affiliation: Department of Physics, Florida State University , Tallahassee, Florida 32306, United States.
authors.forename: Eric
authors.initials: E
authors.lastname: Lochner
authors.affiliation: Department of Chemistry and Macromolecular Studies Group, Louisiana State University , Baton Rouge, Louisiana 70803, United States.
authors.forename: M Graça H
authors.initials: MG
authors.lastname: Vicente
authors.affiliation: Department of Chemistry and Macromolecular Studies Group, Louisiana State University , Baton Rouge, Louisiana 70803, United States.|School of Materials Science and Engineering, School of Chemistry and Biochemistry and Georgia Tech Polymer Network, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Russo
mesh_terms: D000480:Alkynes / Q000737:chemistry; D001386:Azides / Q000737:chemistry; D057930:Click Chemistry / Q000379:methods*; D004655:Emulsions / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008665:Metalloporphyrins / Q000138:chemical synthesis* / Q000737:chemistry; D053761:Nanocomposites / Q000737:chemistry; D056951:Photoelectron Spectroscopy; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013818:Thermogravimetry; D014961:X-Ray Diffraction; D015032:Zinc / Q000737:chemistry
chemical_list: D000480:Alkynes; D001386:Azides; D004655:Emulsions; D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; D008665:Metalloporphyrins; C000499:ferric oxide; D012822:Silicon Dioxide; D015032:Zinc
keywords: click chemistry; iron oxide; metalloporphyrin; silica; superparamagnetic