PMID- 18661538
OWN - NLM
STAT- MEDLINE
DCOM- 20090408
LR  - 20191210
IS  - 1520-6017 (Electronic)
IS  - 0022-3549 (Linking)
VI  - 98
IP  - 3
DP  - 2009 Mar
TI  - Cascade impactor practice for a high dose dry powder inhaler at 90 L/min: NGI 
      versus modified 6-stage and 8-stage ACI.
PG  - 1028-39
LID - 10.1002/jps.21501 [doi]
AB  - The compendial methods of particle size distribution (PSD) profile determination 
      for dry powder inhalers (DPIs) were compared between the Next Generation 
      Pharmaceutical Impactor (NGI) and the Andersen Cascade Impactor (ACI). Relenza 
      Rotadisk (zanamivir) and Diskhaler was used as a model DPI and sampled into each 
      impactor via its preseparator (PS), at 90 L/min under various protocols. In the 
      NGI, silicone coating was shown to be indispensable to prevent or minimize 
      particle bounce and reentrainment, and to reduce wall losses to the levels 
      acceptable to the compendia (5%). In contrast, the ACI exceeded this 5% limit, 
      regardless of coating, implying different wall loss mechanisms from the NGI. 
      Particle bounce occurred in both impactors, inaccurately undersizing the PSD 
      profiles for Relenza, unless the collection surfaces were coated or an increased 
      number of doses were employed. Hence, the PSD profile for Relenza following 
      single dose collection in the stage-coated NGI was the most accurate. In 
      contrast, the use of the ACI and its PS for Relenza at 90 L/min suffered from 
      several problems, even though the poorly designed PS still resulted in consistent 
      impactor dose and PSD profiles, compared to those obtained from the NGI and its 
      PS.
CI  - (c) 2008 Wiley-Liss, Inc. and the American Pharmacists Association
FAU - Kamiya, Akihiko
AU  - Kamiya A
AD  - Department of Pharmaceutics, School of Pharmacy, Virginia Commonwealth 
      University, 410 N. 12th Street, P. O. Box 980533, Richmond, Virginia 23298-0533, 
      USA.
FAU - Sakagami, Masahiro
AU  - Sakagami M
FAU - Byron, Peter R
AU  - Byron PR
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Validation Study
PL  - United States
TA  - J Pharm Sci
JT  - Journal of pharmaceutical sciences
JID - 2985195R
RN  - 0 (Silicones)
SB  - IM
MH  - Administration, Inhalation
MH  - Drug Delivery Systems/*instrumentation/methods/standards
MH  - Humans
MH  - Metered Dose Inhalers/*standards
MH  - Particle Size
MH  - Silicones/chemistry
EDAT- 2008/07/29 09:00
MHDA- 2009/04/09 09:00
CRDT- 2008/07/29 09:00
PHST- 2008/07/29 09:00 [pubmed]
PHST- 2009/04/09 09:00 [medline]
PHST- 2008/07/29 09:00 [entrez]
AID - S0022-3549(16)32890-8 [pii]
AID - 10.1002/jps.21501 [doi]
PST - ppublish
SO  - J Pharm Sci. 2009 Mar;98(3):1028-39. doi: 10.1002/jps.21501.