Bio-Rad BioLogic DuoFlow Valves - Manual (Page 2)

Valve Plumbing
Both the V9-8 and AV9-8 valves accept 1/4-28 flat bottom fittings, and either 1/16" OD/0.020" ID Tefzel
tubing or 1/8" OD, 0.062" ID PTFE tubing may be used. To maintain bio-compatibility, all wetted parts are
non-metallic. The V9-8 and AV9-8 Stream Select valves have numerous uses as part of a chromatography
system, and this will determine the plumbing. Three examples are provided in the following pages.
Note: Always manually prime all pre-column valves before initiating a run. Failure to displace air with buffer could stall the
BioLogic Gradient Pumps or lead to erratic flow.
Example 1. Sample Selection.
The AV9-8 may be used for selecting up to 8 samples for consecutive chromatography runs. Typically, one of the
eight positions holds a rinse solution to clean the sample loop and fill lines between sample injections. For this
example, 1/16" OD/0.020" ID Tefzel tubing is recommended.
LOADING DIRECTLY ONTO A LOW PRESSURE COLUMN USING A PERISTALTIC PUMP TO FILL A STATIC LOOP
In the illustration above, the following two configurations are shown:
• Using a peristaltic pump to load directly onto a column: To load samples onto a column with low
backpressure, bypass the sample loop and directly load sample from the Model EP-1 Econo Pump onto
the column.
• Using a peristaltic pump to fill a static loop: The system can be configured so that the Model EP-1
Econo Pump automatically loads the sample loop. Load at least a 3-fold excess of sample into a static
loop with the peristaltic pump. This helps to ensure that the sample loop is completely filled with
sample prior to injection.
EP-1 ECONO
PUMP
1
2
3
4
5
6
9
7
8
SAMPLE #1
SAMPLE #2
SAMPLE #3
1
2
3
4 5
6
7
COLUMN
WASTE
GRADIENT
PUMP
STATIC
LOOP
LOOP OVERFILL
TO WASTE
V7-3 OR AV7-3
LOAD
POSITION
V9-8 OR AV9-8
RINSE
LOAD
PUMP
1
2
3
4
5
6
9
7
8
SAMPLE #1
SAMPLE #2
SAMPLE #3
LOAD
PUMP
PURGE
1
2
3
4 5
6
7
COLUMN
GRADIENT
PUMP
V7-3 OR AV7-3
INJECT
POSITION
V9-8 OR AV9-8
RINSE