title: Formation and characterization of polyglutamate core-shell microspheres.
abstract: The need for organ-targeted delivery of drugs and imaging agents creates an interest in biocompatible, biodegradable vesicles. We make protein microspheres using high-intensity ultrasound; these microspheres have a protein shell and a hydrophobic interior, making them ideal for delivering hydrophobic materials. We have previously shown that various proteins, e.g., bovine serum albumin (BSA), form a microsphere shell stabilized by interprotein cross-linking of cysteine residues. In this study, polyglutamate was used to form core-shell microspheres at slightly basic pH using sonication. These particles are smaller than our previous protein microspheres and are stable under conditions encountered in vivo. The stability of polyglutamate microspheres appears to be due to hydrogen bonding networks and not covalent cross-linking.
authors.affiliation: Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Dibbern
authors.forename: Farah Jean-Jacques
authors.initials: FJ
authors.lastname: Toublan
authors.forename: Kenneth S
authors.initials: KS
authors.lastname: Suslick
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis; D004355:Drug Stability; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D008863:Microspheres; D009994:Osmolar Concentration; D011099:Polyglutamic Acid / Q000737:chemistry*; D013696:Temperature; D014465:Ultrasonics
chemical_list: D001672:Biocompatible Materials; D011099:Polyglutamic Acid