Waters Viridis SFC Columns - Manual (Page 3)

[ Care and Use ManUal ]
3 Viridis SFC Columns
3. If the sample is not dissolved in the mobile-phase modifier,
ensure that the sample, solvent and mobile phases are miscible
in order to avoid sample precipitation. Filter sample with 0.2 μm
membranes to remove particulates. If the sample is dissolved in
a solvent, ensure that the membrane material does not dissolve
in the solvent. Contact the membrane manufacturer with solvent
compatibility questions. Pall Gelman Laboratory Acrodisc
®
filters are recommended. (Refer to the Waters Chromatography
Columns and Supplies Catalog for additional information.)
Alternatively, centrifugation for 20 minutes at 8,000 rpm,
followed by the transfer of the supernatant liquid to an appropriate
vial, could be considered.
b. Solvents
To maintain maximum column performance, use high quality chro-
matography grade solvents. Solvents containing suspended particulate
materials will generally clog the outside surface of the inlet distri-
bution frit of the column. This will result in higher operating pres-
sure, reduced column lifetime, and compromised performance.
c. Pressure
Viridis SFC columns can tolerate pressures of up to 6,000 psi (400
bar or 40 Mpa) although pressures greater than 4,000 – 5,000 psi
should be avoided in order to maximize column and system lifetimes.
IV. sCALInG UP/DoWn IsoCRAtIC MetHoDs
The following formulas are used for scaling separations.
If column i.d. and length are altered:
F
2
= F
1
(r
2
/r
1
) 2
or
Injection volume
1
= Injection volume
2
(r
2
/r
1
) 2 (L
2
/L
1
)
Where: r = Radius of the column (mm)
F = Flow rate (g/min)
L = Length of column (mm)
1 = Original, or reference column
2 = New column
Table 3 may be helpful in scaling-up the flow rate to maintain sepa-
rations in larger column internal diameters.
Table 3. Flow Rate Scaling Chart
Column Diameter (mm)
4.6 10 19 30 50
Fl
ow r
at
e (
g/
m
in
)
2.5 11.8 42.7 106.3 295.4
3 14.2 51.2 127.6 354.4
3.5 16.5 59.7 148.9 413.5
4 18.9 68.2 170.1 472.6
4.5 21.3 76.8 191.4 531.7
5 23.6 85.3 212.7 590.7
6 28.4 102.4 255.2 708.9
7 33.1 119.4 297.7 827.0
8 37.8 136.5 340.3 945.2
9 42.5 153.5 382.8 1063.3
10 47.3 170.6 425.3 1181.5
V. ConneCtInG tHe CoLUMn to tHe sFC sYsteM
a. Column Connectors and System Tubing Considerations
Tools needed:
 3/8 inch wrench
 5/16 inch wrench
Handle the column with care. Do not drop or hit the column on a
hard surface as it may disturb the bed and affect its performance.
1. Correct connection of 1/16 inch outer diameter stainless steel
tubing leading to and from the column is essential for high
quality chromatographic results.
2. When using standard stainless steel compression screw fit-
tings, it is important to ensure proper fit of the 1/16 inch
outer diameter stainless steel tubing. When tightening or loos-
ening the compression screw, place a 5/16 inch wrench on the
compression screw and a 3/8 inch wrench on the hex head of
the column endfitting.
Note: If one of the wrenches is placed on the column tube flat
during this process, the endfitting will be loosened and leak.