Ethanol pre-treatment of strip-plate?

[Questions from customers]

Dear Mabtech,
 
I purchased #3321-2A from you. For the PVDF plate, I use the type #M8IPS4510 from Millipore. I’m having problems with the pre-wetting step. I add 15ul 35% ethanol per well for 1min, but there are some white spots in the well. It seems like the membrane didn't get properly activated? I ‘m attaching a photo of the plate here:

 
Have you seen this problem before? Is the problem the plate? 
 
Would you give some advice for it?
 
Thank you!

//C
 

[Jens@mabtech.com]

Hi C,

The M8IPS4510-plate is the one we use for our strip-plate kits. However, we only sell it in pre-coated format. This is because we know it is difficult to freshly coat the strip plates: The risk is very high that you get leakage of ethanol in-between the strips, and thus down underneath the membranes, which damages the membranes and causes further leakage – exactly the issue you seem to be having.
 
This is why we don’t sell the strip-plates separately. For ELISpotBASIC, i.e. a fresh-coated assay, we recommend the “normal” non-strip plates MSIPS4510, MSIPS4W10 or MAUPSWU10. More info on these plates can be found here: https://www.mabtech.com/knowledge-center/tutorials-and-guidelines/plate-coating-guide/plates-elispot-and-fluorospot 
 
We also have a youtube-video on the ethanol pre-treatment of these ELISpot plates with some handy tips:

 

If you really really really want to use the strip-plates anyway, you need to think about working very carefully albeit fast. A small trick to at least decrease the risk of leakage in-between strips is to stop the ethanol pre-treatments step by adding water into each well right after you have added the ethanol. The water dilutes the ethanol and makes sure you don’t over-treat the membrane. That way you also don’t have to rush the decanting of the liquid as much and you can be more careful when doing it. But the risk is still high that you will get leakage in-between strips, and thus, I would strongly recommend to use normal non-strip plates instead.
 
Kind regards,
Jens

[Eva]

Hi C, 

After addition of ethanol, I suggest that you tap the plate (not too hard though) so that the ethanol gets evenly distributed.

Kind regards,
Eva