Perform a polyacrylamide gel electrophoresis as described, except do not add to the SDS running buffer or sample buffer. Moreover, it may not be necessary to use gel stacking – only the lower, complete gels may be sufficient.
Band likely to appear more dirty than usual SDS-PAGE. Therefore, run the gel at half the usual tension as a band to have the highest possible resolution. Because it will probably take longer to run, trying to keep as cool as possible with cool gel buffer before use.
For the molecular weight standards, probably a good idea to buy a set of standard weight nondenaturing moelcular for nondenaturing gels.
Transfer the gel and perform blotting as described.
Keep in mind that in the native polyacrylamide gel electrophoresis, protein mobility rate depends on both the size and shape. fibrillar protein will likely be slower than globular proteins.