Encapsulation of Water-Immiscible Solvents in Polyglutamate/ Polyelectrolyte Nanocontainers


  • X.T. is thankful to the China Scholarship Council for a research fellowship and to Dr. Oliver Kreft for kindly helping with the confocal microscopy measurements. We also thank Rona Pitschke for electron microscopy analysis. This work was supported by FP6 EU-project “NANOCAPSULE” and STREP-NMP3-CT-2006–033410 “MatSILC”.


A novel approach for encapsulation of hydrophobic materials into a hydrophilic multifunctional shell is presented, based on combining an ultrasonic technique and a layer-by-layer protocol. Polyglutamate/polyethyleneimine (PEI)/polyacrylic acid (PAA) and polyglutamate/PEI/PAA/silver nanocontainers loaded with a hydrophobic dye, 5,10,15,20-tetraphenylporphin, dissolved in toluene, are fabricated. Uniform, stable, and monodisperse polyglutamate/PEI/PAA nanocontainers of about 600 nm are obtained. The hydrophobic core of the nanocontainers might contain a huge variety of water-insoluble drugs and the outer polyelectrolyte shell may provide controlled permeability and desired multifunctionality. Confocal fluorescence microscopy and scanning electron microscopy are employed for the characterization of the resulting nanocontainers. Using sodium dodecyl sulfate as surfactant, the amount of nanocontainers, their monodispersity, and stability can be increased dramatically.