title: Delivery of nasal powders of beta-cyclodextrin by insufflation.
abstract: OBJECTIVE
  Delivery of nasal powders of granulated beta-cyclodextrin by insufflation was studied in order to find the relationship between powder properties and delivery behavior.
  
  
  METHODS
  Three nasal powder formulations, prepared by granulating beta-cyclodextrin with different binders, were delivered from a powder insufflation device, in which the dose to be emitted was loaded in a gelatin capsule. The delivery sequence of powder was recorded and characterized using an image analysis program.
  
  
  RESULTS
  Particle size was the main parameter affecting nasal powder delivery, both as to the amount of dose sprayed and the aspect of cloud produced. Between 50-150 mu m of particle size a substantial change in delivery behavior of powders was observed. Powder of around 100 mu m in size showed useful insufflation characteristics for nasal delivery. Bioavailability of nasal formulations of progesterone/beta-cyclodextrin powders was discussed in term of delivery behavior.
  
  
  CONCLUSIONS
  The formulation approaches for improving nasal delivery of powders require the use of size optimized carriers. Insufflation of powders over 50 mu m can favour the particle deposition by impaction, whereas for powders below 50 mu m, deposition by sedimentation is moved. beta-cyclodextrin is a suitable carrier for achieving high systemic availability following nasal administration of powder formulations.
authors.affiliation: Pharmaceutical Department, University of Parma, Parma, Italy.
authors.forename: A
authors.initials: A
authors.lastname: De Ascentiis
authors.forename: R
authors.initials: R
authors.lastname: Bettini
authors.forename: G
authors.initials: G
authors.lastname: Caponetti
authors.forename: P L
authors.initials: PL
authors.lastname: Catellani
authors.forename: M T
authors.initials: MT
authors.lastname: Peracchia
authors.forename: P
authors.initials: P
authors.lastname: Santi
authors.forename: P
authors.initials: P
authors.lastname: Colombo
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D001682:Biological Availability; D003505:Cyclodextrins / Q000008:administration & dosage*; D004337:Drug Carriers; D007327:Insufflation; D011208:Powders; D011374:Progesterone / Q000008:administration & dosage / Q000493:pharmacokinetics*; D011817:Rabbits; D047392:beta-Cyclodextrins
chemical_list: D003505:Cyclodextrins; D004337:Drug Carriers; D011208:Powders; D047392:beta-Cyclodextrins; D011374:Progesterone; C031215:betadex