GE HEALTHCARE Biacore T100, Handbook

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4 Application wizards
4.3 Surface preparation wizards
48
Biacore T100 Software Handbook BR-1006-48 Edition AE
Choose the way in which immobilization will be controlled:
• If you choose Aim for immobilized level , you specify a target level. The
immobilization procedure will attempt to reach this level as described
below.
• If you choose Specify contact time and flow rate , enter the settings in the
respective fields.
• If you choose Blank immobilization , the surface will be activated and
deactivated in accordance with the immobilization method but no ligand
will be injected.
Enter the ligand name. To dilute the ligand solution immediately before
injection, check
Dilute ligand and enter a percentage value and a solution
name. This option can be used for ligands that have limited stability in
immobilization buffer, and that are diluted from a stock solution just before
immobilization. A setting of 90% will mix one part of ligand solution with 9 parts
of the specified diluent.
Aiming for immobilized level
The option Aim for immobilized level injects a pulse of ligand over the
unactivated surface in order to estimate the rate of preconcentration. The
surface is washed to remove traces of ligand and then activated. The procedure
then uses ligand contact times based on the preconcentration estimate to
attempt to reach the specified target level. If preconcentration is either too fast
or too slow to permit the target level to be reached, this will be reported and
immobilization will not be performed.
The preconcentration injection injects 10 µl ligand solution at a flow rate of
5 µl/min, giving a contact time of 2 minutes. This injection is included in
predefined methods for CM-series sensor chips but is optional in customized
methods (see below). If
Aim for immobilized level is chosen together with a
custom method that does not include a preconcentration injection, the
immobilization procedure will activate the surface and then inject short pulses
of ligand until either the target level or the maximum total ligand volume of
150 µl is reached. This option can be used to conserve valuable ligand without
losing the benefits of aiming for a target immobilization level, and can be useful
for sensor chips where preconcentration cannot be performed, e.g. Sensor Chip
SA.