Table 1 The impact of pH on disulfide bridge shuffling.

From: The structure-function relationship of disulfide bonds in etanercept

 

pH 8.0

pH 7.5

pH 6.5

pH 5.5

pH 5.0

GP2015 DS

11.3%

9.5%

6.7%

1.3%

1.2%

GP2015 CAP.E

15.5%

12.3%

8.1%

3.9%

4.3%

  1. The table above shows the relative amount of peptide containing the incorrect disulfide bridge C78-C88 in GP2015 drugs substance (DS) samples and GP2015 capture eluate process intermediates (CAP.E) when the digestion step of the non reducing peptide map was carried out at different pH. Higher pH was found to results in high levels of C78-C88, while the level of internal peptide standard remained stable. These data suggest that increased pH promotes disulfide bridge shuffling and results in increased incorrect bridging. In contrast, performance of the non reducing peptide map at pH 6.0 or below resulted in stable low levels of C78-C88 peptide suggesting a repression of shuffling.
Back to article page