THE POTENTIOMETRIC STRIPPING ANALYSIS OF PROTEINS

Ten proteins were analyzed by potentiometric stripping analysis (PSA) following reductive accumulation on a HMDE and oxidation with dissolve d oxygen. During the reductive accumulation period the surface disulfi de bonds are reduced to sulfhydryl pairs. The rate of oxidation nf the sulfhydryl pairs is determined by the transport of dissolved oxygen t o the electrode surface. Comparison of the PSA response to that obtain ed by constant current chronopotentiometry (CCCP) of the reduced prote in in a deoxygenated solution showed that the presence of dissolved ox ygen, in the PSA experiments stabilized the proteins from further conf ormational changes following the reduction of the surface disulfide bo nds.