title: The importance of nonelectrostatic materials in holding chambers for delivery of hydrofluoroalkane albuterol.
abstract: BACKGROUND
  Electrostatic attraction of aerosolized particles to the inner walls of an aerosol holding chamber (HC) made from a nonconducting material can reduce medication delivery, particularly if there is a delay between actuation and inhalation.
  
  
  OBJECTIVE
  Compare total emitted mass and fine-particle mass (mass of particles < 4.7 microm) of hydrofluoroalkane-propelled albuterol from similar-sized HCs manufactured from conductive material (Vortex), charge-dissipative material (AeroChamber Max), and nonconductive material (OptiChamber Advantage, ProChamber, Breathrite, PocketChamber, and ACE), with and without wash/rinse pretreatment of the HC interior with ionic detergent, and with 2-s and 5-s delays between actuation and inhalation.
  
  
  METHODS
  All the HCs were evaluated (1) directly from their packaging (with no wash/rinse pretreatment) and (2) after washing with ionic detergent and rinsing and drip-drying. We used an apparatus that interfaced between the HC mouthpiece and the induction port of an 8-stage Andersen cascade impactor to simulate a poorly coordinated patient, with delays of 2 s and 5 s between actuation and inhalation/sampling, at 28.3 L/min.
  
  
  RESULTS
  With the 2-s delay, the delivered fine-particle mass per actuation, before and after (respectively) wash/rinse pretreatment was: AeroChamber Max: 23.8 +/- 4.8 microg, 21.5 +/- 3.2 microg; Vortex: 16.2 +/- 1.7 microg, 15.5 +/- 2.0 microg; OptiChamber Advantage: 2.6 +/- 1.2 microg, 6.7 +/- 2.3 microg; ProChamber: 1.6 +/- 0.4 microg, 5.1 +/- 2.5 microg; Breathrite: 2.0 +/- 0.9 microg, 3.2 +/- 1.8 microg; PocketChamber: 3.4 +/- 1.6 microg, 1.7 +/- 1.6 microg; ACE: 4.5 +/- 0.9 microg, 5.4 +/- 2.9 microg. Similar trends, but greater reduction in aerosol delivery, were observed with the 5-s delay. Significantly greater fine-particle mass was delivered from HCs made from conducting or charge-dissipative materials than from those made from nonconductive polymers, even after wash/rinse pretreatment (p < 0.01). The fine-particle mass was also significantly greater from the AeroChamber Max than from the Vortex, irrespective of wash/rinse pretreatment or delay interval (p < 0.01).
  
  
  CONCLUSIONS
  HCs made from electrically conductive materials emit significantly greater fine-particle mass, with either a 2-s or 5-s delay, than do HCs made from nonconducting materials, even with wash/rinse pretreatment.
authors.affiliation: Cardiopulmonary Care Sciences, Georgia State University, Atlanta, Georgia 30084, USA. joerau@comcast.net
authors.forename: Joseph L
authors.initials: JL
authors.lastname: Rau
authors.forename: Dominic P
authors.initials: DP
authors.lastname: Coppolo
authors.forename: Mark W
authors.initials: MW
authors.lastname: Nagel
authors.forename: Valentina I
authors.initials: VI
authors.lastname: Avvakoumova
authors.forename: Cathy C
authors.initials: CC
authors.lastname: Doyle
authors.forename: Kimberly J
authors.initials: KJ
authors.lastname: Wiersema
authors.forename: Jolyon P
authors.initials: JP
authors.lastname: Mitchell
mesh_terms: D000335:Aerosol Propellants / Q000032:analysis*; D000420:Albuterol; D016503:Drug Delivery Systems; D004868:Equipment Failure; D006801:Humans; D006845:Hydrocarbons, Fluorinated; D009864:Ontario; D019064:Product Packaging; D055672:Static Electricity; D005466:Fluorocarbons
chemical_list: D000335:Aerosol Propellants; D000420:Albuterol; D006845:Hydrocarbons, Fluorinated; C094049:apaflurane; D005466:Fluorocarbons