Figure 4.

NR‐GX images of harvested cell culture fluid (HCCF) at t = 0 and 2 weeks, containing 0, 0.4, and 0.8 mM cystine per gram mAb. During 2 week hold, HCCF was held at 2–8°C in air‐tight bags. (Note: a separate aliquot of the same HCCF at t = 0 was spiked to 0.4 mM cystine per gram mAb and purified after a 4 day hold at 2–8°C in a vessel with headspace and is listed as purification Run 3 in Table I).