Bis(sulfosuccinimidyl) suberate (BS3) crosslinking analysis of the behavior of amyloid-β peptide in solution and in phospholipid membranes

The structure and state of amyloid-β peptide (Aβ) oligomers often need to be checked by reliable experimental methods. Electrophoresis is a commonly applied measurement method. However, due to the presence of detergents, oligomers are easily broken during electrophoresis, which makes it very hard to accurately assess Aβ aggregate states. In the current study, bis(sulfosuccinimidyl) suberate (BS3) was used to cross-link Aβ1-42 oligomers prior to electrophoresis. When compared to a previously reported Aβ cross-linking agent, glutaraldehyde, it was quite apparent that BS3 is more suitable for detecting intra-membrane Aβ oligomers and extra-membrane Aβ oligomers states. As such, our findings provide an efficient method for analyzing Aβ proteins or other proteins that are easily aggregated in solution and in phospholipid membranes.