What is the yeild expected for an efficient IP? - (May/24/2012 )

I'm doing a co-IP and I wanna first make sure that I pull down enough of my protein . So when I do a western blot and compare the protein in my total lysate with the IP it looks like that I'm only precipitating about %2 of the protein (comparing a %2.5 input with the total output). I'm using an anti-serum which is not purified but is highly specific for my protein. Does any body know if this yield is normal? which steps I should work on to increase the yield? adding more serum to my tissue lysate? and/or adding more sepharose beads? it's also worth mentioning that most of the protein remains in the supernatant after the incubation with antiserum and the beads!

Thanks

I got ~0.3% only from plant tissue. It doesn't matter for me since it is enough for further process. Try to use more beads.

Thanks Arun,
I've already increased the amount of beads so right now I'm adding ~50 ul of slurry beads to 140 ul of lysate which has a total protein concentration of ~15 ug/ul. I'm afraid if I increase the beads more than this or if I add more of the antiserum used for IP I will increase the non-specific pull down. currently all of the proteins which I'm testing for Co-IP are also present in the IP using preimmune serum