Agarose gel electrophoresis of native AP205 VLP, bPEG9-AP205 VLP, bPEG17-AP205 VLP, bPEG25-AP205 VLP, and mPEG25-AP205 VLP in PBS and in pig gastric fluid (pH 3.0), respectively, on the left and right of the gel. Incubation times varied between 5 min, 30 min, 1 h, and 2 h at 37 C. Arrows at time point 5 min indicate persistent PEG-cross-linked AP205 VLPs in gastric fluid. M stands for marker.
