Validating AIM-Based Instrumentation and Associated Measurement Techniques - Good Cascade Impactor Practices, AIM and EDA for Orally Inhaled Products - page 298

13%w/w ethanol

8%w/w ethanol

70
60
50
40
30
20
10
0

70

ACI
FSA
mFSA

ACI

60
50
40
30
20
10
0

FSA
mFSA

**

*

>5 µ m ≤ 5 µ m ≤ 1 µ m

>5 µ m ≤ 5 µ m ≤ 1 µ m

13%w/w ethanol+
1.3% glycerol

26%w/w ethanol

70
60
50
40
30
20
10
0

ACI
FSA
mFSA

70
60
50
40
30
20
10
0

ACI
FSA
mFSA

**

**

>5 µ m ≤ 5 µ m ≤ 1 µ m

≤ 5 µ m

>5 µ m ≤ 1 µ m

Fig. 10.19 Comparison of impactor size fractions (ANOVA; * p < 0.05; ** p < 0.01) from solution
formulations containing 100 L dose ( n = 3; ±SD). mFSA modified FSA as

described above ( From [ 28 ]— used with permission )

μ g BDP per 50 μ

Table 10.8 Residual FSA-measured particle dose values relative to associated ACI values a
( From [ 28 ]— used with permission )

Ethanol content (%w/w)
8%

13% 26%

Metric FSA type μ g % μ g % μ g %

CPM >5.0μm FSA −1.1 4.5 −4.9 13.1 −4.8 8.4

mFSA −0.3 1.2 −1.4 4.1 −2.5 4.4

FPM <5.0μm FSA 3.8 6.2 4.9 9.6 8.4 30.4

mFSA 1.3 2.0 3.8 7.5 3.6 13.0

EPM <1.0μm FSA −2.0 8.6 −2.4 13.0 2.3 22.8

mFSA −3.6 15.5 −3.2 17.3 −0.9 8.9

a Bold typeface indicates a difference of >10% of the ACI reported value

The outcome depicted confirms the previously reported observation of impaction
of partially evaporated droplets from solution MDI formulations containing ethanol
[ 20 ]. However, Keegan and Lewis noted that the addition of the “spacer” stage to
the FSA did not make any significant difference to the BDP deposition observed for