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Refill the reference cell
Introduction
The MicroCal PEAQ-ITC instrument has two cells, the sample cell and the reference cell.
The reference cell must be refilled manually. An underfilled reference cell can result in a
starting baseline position
greater
than specified in the ITC Method.
Refilling the reference cell is recommended approximately once a week.
Procedure
The following steps describes how to refill the reference cell.
Step
Action
1
Gently insert a glass Hamilton syringe into the reference cell until it touches the bottom.
2
Empty the reference cell completely by pulling up the syringe plunger.
Note
: Make sure that no bubbles are trapped in the cell.
3
Remove and empty the syringe. Clean the syringe, if necessary.
4
Pull approximately 300 μl of degassed, distilled water into the syringe.
Tap the syringe glass gently so that all the bubbles are at the top volume of the syringe.
5
Insert the syringe into the cell and gently touch the bottom of the cell with the tip of the
syringe needle.
Raise the needle tip about 1 mm off the bottom of the cell (as illustrated in the trans-
parent cell model), and hold it there during the filling process.