I am using a biacore t-100 with a CM4 chip. Last week, everything went fine, I immobilized my protein, and measured some interactions.
This week, I opened a package with a new chip, docked it, primed the system, and ran an immobilization scouting (just like last week with the old one, the chip is also the same type). To my surprise, I got absolutely no response to any of the injections (meaning that the baseline is completely flat after each of the injections, regardless of the injected material.) I would at least expect a harsh signal during regeneration with 50 mM NaOH, but no response at all (meaning RU change = 0). The machine absorbs the material, consumes buffer and water, the chip is docked in the right direction, and there are no error messages from the software.
Does anyone have an idea on what's happening? Please tell me it is some ridiculously obvious thing which I haven't noticed.
I appreciate any kind of help.