Figure 1.
Molecular weight analysis of silk fibroin solutions. (A) SDS-PAGE showed that the 5 mb sample had a visible band around the highest molecular weight marker, while the 30 mb and 60 mb samples were visible as smears lower down the gel (mb = minutes boiled). (B) Densiometric analysis of protein distribution along the gel showed that the 30 mb sample had a peak around 150 kDa, while the 60 mb peak was around 50 kDa. (C) Gel permeation chromatography showed that the 5 mb sample was first to elute from the column, followed by the 30 mb and then the 60 mb sample. The peak of the 5 mb sample eluted at 4.0 minutes, the 30 mb sample at 5.1 minutes, and the 60 mb sample at 5.9 minutes.