ProTeon Big Issue

Have you guys encountered this? The Bio-rad technical expert came and told me there is no issue. However, I have just started a new chip, and inject water horizontal (3 times) followed by inject water vertical (3 times). And attached is the profiles i got. There are weird traces .....
I hope someone has the same experience and can tell me what to fix.

Hi,

First, I am not familiar with the ProteOn internal workings but it seems to me that it is in the injection system.
SPR instruments are sometimes sensitive to flow rate differences. It might be the case that the injection system is not running smoothly all the time during the injection and in this way making pressure differences.
With Biacore type of instruments replacing the syringes that deliver the analyte can help.
To get a better understanding of the problem you can inject buffer at the same flow rate for different flow periods (e.g. 1, 2, 3, 4, 5 minutes) and see when the curves (time and injected volume) begin to deviate.
Please post 1 or two bigger graphs so we can see the legends.

Kind regards
Arnoud