Journal of Nanoparticle Research

, Volume 10, Supplement 1, pp 121–130 | Cite as

Combined synthesis and in situ coating of nanoparticles in the gas phase

  • Anna Lähde
  • Janne Raula
  • Esko I. KauppinenEmail author
Research Paper


Combined gas phase synthesis and coating of sodium chloride (NaCl) and lactose nanoparticles has been developed using an aerosol flow reactor. Nano-sized core particles were produced by the droplet-to-particle method and coated in situ by the physical vapour deposition of L-leucine vapour. The saturation of L-leucine in the reactor determined the resulting particle size and size distribution. In general, particle size increased with the addition of L-leucine and notable narrowing of the core particle size distribution was observed. In addition, homogeneous nucleation of the vapour, i.e. formation of pure L-leucine particles, was observed depending on the saturation conditions of L-leucine as well as the core particle characteristics. The effects of core particle properties, i.e. size and solid-state characteristics, on the coating process were studied by comparing the results for coated NaCl and lactose particles. During deposition, L-leucine formed a uniform coating on the surface of the core particles. The coating stabilised the nanoparticles and prevented the sintering of particles during storage.


Aerosol Coating Gas-phase Nanoparticles Pharmaceutical Processing 


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.NanoMaterials Group, Laboratory of PhysicsHelsinki University of TechnologyEspooFinland
  2. 2.VTT BiotechnologyEspooFinland

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