Biotage Selekt Enkel, Руководство пользователя

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31
Maintenance
4. Flush the flow cell with a series of miscible solvents or a
detergent solution (see “Wash solution” below) using the
injection maintenance kit supplied with the system.
Wash solution
»
A series of miscible solvents
Select the solvents based on the contamination. It is
possible to use both organic and inorganic solvents and
diluted solutions of acids (e.g. H
2
SO
4
or HNO
3
diluted
with distilled water in a ratio of 1:20 to 1:10), unless they
react with stainless steel, PTFE, or fused silica windows.
»
Detergent solution
It is also possible to use a wash solution with 10%
solution of a selected “detergent” in deionized
water, heated to about 40°C (104°F). The following
detergents are approved to be suitable with the
materials used in the flow cell: Decon 90, Deacon
Neutracon (neutral pH), Deconex, and RBS 25.
Note: Do not leave the flow cell for several hours with these
liquids as they can etch the fiber, due to their basicity.
5. Visually re-examine cell windows for visible contamination.
If contamination is still present, either repeat step 4 or try to
sonicate the flow cell:
a. Place the flow cell in the wash solution (see “Wash
solution” in step 4) in an ultrasonic bath.
b. Sonicate for 40 minutes at 40°C (104°F).
If you are not able to remove the contamination, we
recommend that you replace the flow cell (P/N 416331SP)
and recalibrate the internal UV detector (see page 30).
6. When the flow cell is clean, rinse it with plenty of deionized
water and then with a solvent miscible with the system
solvents. Use the syringe supplied with the system.
7. Carefully insert the flow cell and close the retaining nut:
a. Insert the flow cell cone straight into its housing inside
the UV detector; see the highlighted section in Figure 58.
b. Close the retaining nut.
Tip!
At the last couple of turns,
hold the flow cell flat against the retaining nut while
closing the nut completely.
Note:
The retaining nut should close with little effort. If it is
difficult to close, the flow cell is probably misaligned.
8. Reconnect the tubing to the flow cell.
Figure 58. Cross section of the flow cell properly inserted into the
UV detector.
Monthly Maintenance of the Flow Cell
Perform the following flush procedure as part of your scheduled
preventive maintenance.
1. Press Menu and then Flushes and Purge .
2. Select Bypass from the Path drop-down list.
3. Ensure that the column inlet and outlet tubing are coupled
together, on both channels.
4. Enter “30o mL” in the Volume text box.
5. Enter “40 mL/min” in the
Flow Rate
text box.
6. Enter “100%” for the strongest solvent mounted on the
system. Enter “0%” for the other ones.
7. Press Flush .
8. When the flush is completed, allow the system to stand
overnight.
Clean or Release Check Valves
Clean the Pump Check Valves
If the last purification of the day is performed with a
halogenated solvent (e.g. DCM), we recommend that you assign
methanol or a similar solvent to the inlet line used with the
halogenated solvent (see page 5) and flush the system with
at least 30 mL (see page 20) to rinse the halogenated solvent
from the check valves.
Release Stuck Check Valves
Low or inconsistent flow delivery volume and/or superimposed
periodic UV signals can be signs of stuck check valves.
Warning
»
When releasing a stuck check valve, there is a risk of a small
amount of solvent splashing out.
1. Release the pressure by slowly unscrewing the check
valve cap from one of the
CV OUT
valves using the Torx 50
screwdriver supplied with the system; see Figure 59.
Figure 59. Removing the check valve cap from one of the CV OUT valves.
2. Repeat the procedure for the other three check valves.