detecting pH in protein containing samples

[Oliver]

Hello,
I try to use a common pH-electrode (Ingold) to measure pH changes upon
oxygenation of hemocyanin of spiders. The problem is, that I have to use
concentrations between 22 to 32 g/l. The protein is denaturated inside
the diaphragm of the electrode after a short time. Does anybody use the
Friscolyt-electrolyt (Mettler-Toledo) to solve that problem?
 I also don´t know how to change the electrolyte. It´s a mico-electrode
and capillary forces prevent simple change by pipette.

Thank you for any help,

Oliver