Encapsulation of magnetic and fluorescent nanoparticles in emulsion droplets.
Oils containing both fluorescent semiconductor and magnetic oxide nanoparticles are used to produce oil in water emulsions. This technique produces oil droplets with homogeneous fluorescence and high magnetic nanoparticle concentrations. The optical properties of the oil droplets are studied as a function of the droplet sizes for various concentrations of fluorescent and magnetic nanoparticles. For all concentrations tested, we find a linear variation of the droplet fluorescent intensity as a function of the droplet volume. For a given size and a given quantum dot (QD) concentration, the droplet fluorescence intensity drops sharply as a function of the magnetic nanoparticle concentration. We show that this decrease is due mainly to the strong absorption cross section of the magnetic nanoparticles and to a lesser extent to the dynamic and static quenching of the QD fluorescence. The role of the iron oxide nanoparticle localization in the droplet (surface versus volume) is also discussed.
Mandal
Swapan K
SK
Laboratoire colloïdes et matériaux divisés, CNRS UMR 7612, ESPCI, 10 rue Vauquelin, 75231 Paris, France.
Lequeux
Nicolas
N
Rotenberg
Benjamin
B
Tramier
Marc
M
Fattaccioli
Jacques
J
Bibette
Jerome
J
Dubertret
Benoit
B
D000327:Adsorption; D004655:Emulsions / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D005453:Fluorescence; D008280:Magnetics; D008856:Microscopy, Fluorescence; D049329:Nanostructures; D036103:Nanotechnology; D009821:Oils / Q000737:chemistry*; D010316:Particle Size; D045663:Quantum Dots; D013499:Surface Properties; D013997:Time Factors
D004655:Emulsions; D005290:Ferric Compounds; D009821:Oils; C000499:ferric oxide