I am not familiar with trying to patch clamp sperm. Is it achieving a gigaseal that is the problem? or is it the motility of the sperm? If you are unable to get a gigaseal, you could do quantative calcium imaging. If you load a cell with high enough membrane-permanent calcium dye, you can get calcium entry kinetics. When the dye is at high concentration, essentially every calcium ion is captured by a dye molecule, and the fluorescence measurement will give an integral of calcium entry. Then take the derivative of that time course to get instantaneous calcium entry.

Hi, a colleague of mine was very successful in sperm patch-clamping. Check out Article Recording Electrical Currents across the Plasma Membrane of ...