Intact Nanoparticulate Indomethacin in Fast-Dissolving Carrier Particles by Combined Wet Milling and Aerosol Flow Reactor Methods
Drug development is often hindered by a drug's low dissolution rate. We present a method to increase dissolution rate of a drug powder by producing crystalline nanoparticles that are dispersed in carrier microparticles.
Indomethacin crystals of a few hundred nanometers are prepared by media milling using poloxamer 188 as a stabilizer. Nanoparticles are embedded into microparticles with a mannitol matrix and an L-leucine coating layer using an aerosol flow reactor method.
Microparticles stabilize the primary nanoparticles in an intact crystalline form and release them when re-dispersed in aqueous medium. Secondary microparticle structure dissolves rapidly, resulting in a fast release and dissolution of indomethacin. In this manner, it is possible to change the surface layer of the particles from the one needed for nanoparticle production to one more suitable for process formulation of pharmaceuticals for, e.g., tablet or pulmonary products.
Particle assemblies where nano-sized crystalline drug domains are embedded in solid microparticles are presented. The present work is a promising approach towards a “nanos-in-micros” concept as a tool for pharmaceutical nanoparticle processing.
KEY WORDSaerosol flow reactor drug dissolution media milling microparticles nanoparticles
JR, AR, and EK acknowledge support from the Academy of Finland (project no. 133407).
- 13.Eerikäinen H, Peltonen L, Raula J, Kauppinen EI, Hirvonen J. Nanoparticles containing ketoprofen and acrylic polymers prepared by an aerosol flow reactor method. AAPS PharmSciTech. 2004;5:article 68.Google Scholar
- 24.Raula J, Kauppinen EI, Huck D, Kippax P, Virden A. Characterizing carrier-free DPI formulations: using laser diffraction and morphological imaging to examine aerosolization performance of carrier-free inhalation powders. Inhalation. 2010;4(4):8–11.Google Scholar
- 26.Liu P, Rong X, Hirvonen J, Laaksonen T, Peltonen L. Nanosuspension of poorly soluble drugs: preparation and development by wet milling. Int J Pharm. 2011. 10.1016/j.ijpharm.2011.03.050.