Mouse secondary causing very faint markers

Hi,

We have recently (in the last 6 months) been having a problem where our mouse secondaries are requiring very high concentrations (1:500 gives ok results with the previous company and 1:5000 was ok with the new company, the new one used to work well with 1:20000). We also need to use 5ul on marker just to see the bands whereas before the problems started we were using 2ul with no problem and 1:2000 dilutions.


Has anyone ever seen this before? The rabbit secondaries are fine. It also seems like it would only really affect the markers.


We are using MagicMark XP.


Thanks

 Can you provide the links to the products pages on the web for the old secondary antibody and the new one that you are now using that appears to work less well?

This will help to do an apples to apples comparison and see where any problems may lie for you