Figure 7.

Solubility and aggregation propensity of GCSF, 5kPEG-GCSF, and 20kPEG-GCSF. (A) Percent soluble material as assessed by SEC for an incubation time course of GCSF (filled circles), 5kPEG-GCSF (open circles), and 20kPEG-GCSF (filled triangles) at pH 6.9, 37°C. (Inset) SDS-PAGE of GCSF (“G”), 5kPEG-GCSF (“5PG”), and 20kPEG-GCSF (“20PG”) to demonstrate their relative sizes. (B) From SEC measurements, the percent aggregate present in the sample at a given time point was estimated for GCSF as insoluble aggregates (from loss of main peak, closed circle), or as soluble aggregates for 5kPEG-GCSF (open circle) and 20kPEG-GCSF (closed triangle).