Biomedical Engineering Reference
In-Depth Information
Table 2
Log
D
(7.4) of the compounds
Analyte
A
B
C
D
E
F
Log
D
7.4
−0.32
−0.32
0.83
2.47
6.79
6.98
a
b
20
30
15
25
20
10
15
10
5
5
0
0
0
10
20
30
40
50
60
0
10
20
30
40
50
60
Spotting Volume (
µ
L)
Spotting Volume (
µ
L)
c
d
20
30
25
15
20
10
15
10
5
5
0
0
0
10
20
30
40
50
60
0
10
20
30
40
50
60
Spotting Volume (
µ
L)
Spotting Volume (
µ
L)
Fig. 3
Mean concentration (
center punches
) vs. spotting volume for (
a
) Compound A on VWR
237 paper; (
b
) Compound A on FTA Elute; (
c
) Compound F on VWR 237 paper; (
d
) Compound
F on FTA Elute cards
compound for 5 mL spotting volume on the VWR 237 paper. On the other hand, the
center concentration of Compound A for 50 mL spotting volume was approximately
170 % of that of the same compound for 5 mL spotting volume for the FTA Elute card.
For Compound F with high log
D
, similar trends were observed, and VWR 237 paper
show more consistent mean concentration with larger standard deviation, while the
FTA Elute cards show more change in center spot concentration across different vol-
umes with smaller standard deviation among replicates. Based on the observed trends,
a conclusion can be drawn that a certain measure of control needs to be utilized for the
spotted volume. Depending on the acceptance criteria of the individual assay, more or
less variation of the spotted volume may be acceptable. The most accurate concentra-
tion will still be obtained when an accurate volume is spotted.
