Electrophoretic separation of large proteoglycans in large-pore polyacrylamide gradient gels (1.32–10.0% T) and a one-step procedure for simultaneous staining of proteins and proteoglycans

A procedure is described for the preparation of 1.32–10% polyacrylamide gradient gels. Loose polyacrylamide gel on the top side of the gradient was stabilized with a layer of 0.4% agarose gel which also formed sample wells. The upper limit of separation achieved in these gels was estimated to be approximately 2 × 10 6 using globular protein standards. However, large aggregating proteoglycans from cartilage which have a molecular weight range of 1–4 × 10 6 penetrate and separate in these gels. A simple one-step procedure is also described for simultaneous staining of proteins and large proteoglycans in polyacrylamide gels.