title: Enhanced bioavailability of danazol nanosuspensions by wet milling and high-pressure homogenization.
abstract: BACKGROUND
  The majority of drugs obtained through synthesis and development show poor aqueous solubility and dissolution velocity, resulting in reduced bioavailability of drugs. Most of these problems arise from formulation-related performance issues, and an efficient way to overcome these obstacles and to increase dissolution velocity is to reduce the particle size of drug substances to form drug nanosuspensions.
  
  
  METHODS
  Danazol nanosuspensions were prepared by wet milling (WM) and high-pressure homogenization (HPH) methods. The nanosuspensions obtained using these fabrication methods were analyzed for their particle size, surface charge, and the crystallinity of the product was assessed by X-ray diffraction (XRD) and differential scanning calorimetry techniques. To determinein vitroandin vivoperformances of the prepared nanosuspensions, dissolution velocity, and bioavailability studies were performed.
  
  
  RESULTS
  Particle size and zeta potential analysis showed the formation of nanosized particles with a negative charge on the surface. XRD depicted the nanocrystalline nature of danazol with low diffraction intensities. With increased surface area and saturation solubility, the nanosuspensions showed enhanced dissolution velocity and oral bioavailability in rats when compared to the bulk danazol suspension.
  
  
  CONCLUSIONS
  The results suggest that the preparation of nanosuspensions by WM or HPH is a promising approach to formulate new drugs or to reformulate existing drugs with poorly water-soluble properties.
authors.affiliation: Division of Pharmaceutics, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA.
authors.forename: Naveen
authors.initials: N
authors.lastname: Kanthamneni
authors.affiliation: Formulation and Analytical Research and Development, RiconPharma, Denville, NJ 07834, USA.
authors.forename: Satyanarayana
authors.initials: S
authors.lastname: Valiveti
authors.affiliation: Small Molecule Discovery Research, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT 06877, USA.
authors.forename: Mita
authors.initials: M
authors.lastname: Patel
authors.affiliation: Small Molecule Discovery Research, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT 06877, USA.
authors.forename: Heather
authors.initials: H
authors.lastname: Xia
authors.affiliation: Small Molecule Discovery Research, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT 06877, USA.
authors.forename: Yin-Chao
authors.initials: YC
authors.lastname: Tseng
keywords: Danazol; high-pressure homogenization; nanosuspensions; wet milling