ProteOn XPR36, User Manual

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ProteOn XPR36 System | C Surface Plasmon Resonance
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Analyte Interaction Process
Analyte Step
During this step, injected analyte flows across the immobilized ligand, with
real-time monitoring of the interaction. The phases of the SPR response
during this step are:
• Association phase — Interval during which injected analyte
interacts with the ligand surface
• Dissociation phase — Interval during which analyte-free running
buffer flows over the sensor chip surface, causing the ligand-
analyte complex to dissociate
Important considerations for accurate interaction analysis are appropriate
buffer conditions, analyte concentration, flow rate, contact time (interaction
time), and dissociation time (buffer running time).
• Running buffer — Analyte is prepared in a buffer of appropriate pH
and ionic strength to support optimum activity of both reaction
partners. Dilution of analyte in running buffer is recommended to
minimize bulk effects (refractive index difference between two
solutions)
ProteOn phosphate buffered saline with Tween 20 (PBST), pH 7.4,
is the recommended running buffer for most ProteOn XPR36
system applications. The running buffer should contain salt
(ProteOn PBS contains 10 mM sodium phosphate and 150 mM
sodium chloride, pH 7.4) and a surfactant, such as Tween 20, to
minimize the adsorption of proteins to the microfluidics tubing and