ProteOn XPR36, Руководство пользователя

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ProteOn XPR36 System | C Surface Plasmon Resonance
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Deactivation and Stabilization Steps
Following immobilization of the ligand, any remaining activated carboxylic
groups on the chip surface are deactivated with 1M (Molar)
ethanolamine
hydrochloride, pH 8.5. Addition of this reagent also removes any remaining
electrostatically bound proteins. The flow rate is generally the same as that
used for activation and immobilization, and the contact time is dictated by the
degree of activation used. For strong activations, longer contact times are
used for deactivation (6 min). For mild activations, use shorter contact times
(3–4 minutes).
Following deactivation, an optional—but recommended—stabilization
(preconditioning) step is performed to wash nonspecifically bound molecules
from the chip surface. Stabilization of the sensor chip surface can be
accomplished by performing one or more blank injections or by using
reagents from the ProteOn regeneration kit. In applications that use high
ligand densities, such as small-molecule interactions, the high ligand
concentrations and contact times used during immobilization may cause
some ligand to bind noncovalently to the chip surface and generate a baseline
drift. Stabilization is performed to achieve a stable, nondrifting baseline. Any
one of the regeneration solutions can be used for preconditioning, but an
empirical choice should be made for every case. The chosen solution should
yield optimum stabilization with minimal impact on the ligand activity. The
exposure time to the stabilization solution should be as short as possible to
minimize possible damage to the ligand.