Dear all,
I am a PhD student. I am working on a isotope labeled heme uptake experiment by bacteria cells. Now I have a problem about the filter for heme: after I incubate my cells with heme in medium, I am trying to filter out the unbound heme and take the membrane filter to the gamma counter with the cells on it. But I find there are always a lot of unbounded heme sticks to the membrane and generates a high background, which pretty much ruins the experiments. I have tried several different kinds of membrane filters and right now I am using celluloseacetat filter but the background is still quite high.
I want to ask that what kind of membrane filter has the least non-specific binding for heme? And also, what kind of washing buffer is good to wash the filter to get rid of the non specific binding heme.
Thank you!
