I've noticed that my beta casein assays are no longer working. I'm not sure what is going on since my whole casein assays work just fine.
In order to eliminate all possible causes of problems, I've gone ahead and reordered more alpha, beta, and kappa casein. I'm also going to prepare a new solution of PEM. Except now what I plan on doing is making a 10x solution of PEM. I will then aliquot it into convenient quantities and store them in the freezer. I have absolutely no clue if there is gunk in my stock solution of PEM or not and this is the cause of the problems.
So far, I know the following:
- My PEM can be aliquoted easily. It can also be stored in the freezer with no problem so why I'm not doing this already is just silly. I'm not sure what the proper containment vessel should be but I'm leaning towards screw-top vials.
- The way I prepare Antifade is working out just fine. Although, the BME may have a shelf life of only 6 months and I've gone well over that time frame. Everything seems to work for now so I'm not going to change anything.
- It would appear that my casein solutions definitely have a shelf life. This means that I'm going to have to freeze them and aliquot them out appropriately. Again, I think screw-top vials may be best.
- I've started to aliquot my Taxol into microcentrifuge tubes. However, I'm not sure it is working out doing this. I've had MTs destruct for the last 2 assays I've done. I know for a fact that when I was not aliquoting the Taxol solution, it lasted for the same amount of time for when I do aliquot. I was hoping that by aliquoting, it would save me from wasting chemicals.