title: Nanoparticle-stabilized colloids in compressible hydrofluoroalkanes.
abstract: In this work, we show that nanoparticles (NPs) dispersed in compressible hydrofluoroalkanes (HFAs) at small volume fractions are capable of stabilizing micrometer-sized particle colloids, which otherwise flocculate due to strong van der Waals forces. Water-soluble, biodegradable NPs with a chitosan (CS) core, grafted with highly HFA-philic moieties, can be readily dispersed in the low dielectric HFAs and are capable of imparting stability to a wide range of therapeutic particles having different chemistries (polar or hydrophobic; small and large molecular weight, including peptides and proteins) and morphologies (micronized crystals or amorphous). These NP systems thus serve as a broadly applicable platform for the noninvasive delivery of therapeutics to and through the lungs using propellant-based, portable inhalers, and are also of potential relevance in other industries where HFAs are employed as solvents or propellants. This concept may also be applicable to other compressible solvents.
authors.affiliation: Department of Chemical Engineering and Materials Science, Wayne State University, Detroit, Michigan 48202, USA.
authors.forename: Libo
authors.initials: L
authors.lastname: Wu
authors.forename: Sandro R P
authors.initials: SR
authors.lastname: da Rocha
mesh_terms: D048271:Chitosan / Q000737:chemistry; D003102:Colloids / Q000737:chemistry; D006845:Hydrocarbons, Fluorinated / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D003102:Colloids; D006845:Hydrocarbons, Fluorinated; D048271:Chitosan