I don't believe it is critical as to what buffer you use to homogenize the muscle in. You would typically dilute the homogenate in the PK Assay Buffer from the kit by 30-100 fold according to the assay protocol. We typically have used 33-100 mM KPO4 (pH 7.0-7.4) to homogenize muscle in for a lot of metabolic enzyme assays. We typically have homogenized at a 1:30 to 1:50 muscle weight/buffer volume ratio for these kinds of assays. If you could make a more concentrated homogenate, that would minimize any buffer effects.

Hi Gordon,

Thank you for your answer. I also believe that preparation step is not critical but as this kit is relatively expensive, I wanted to make sure of that.

I thought about a first dilution of 1:10 and then a second dilution of 1:50 minimum. I already tested a 1:20 second dilution that wasn't sufficient.

I'll try your solution (KPO4 buffer) in comparison to the buffer provided in the kit and see what happens!

Sophie