Interaction of type I collagen with sepiolite (magnesium silicate)

Type I collagen from calf skin interacts with magnesium silicate (sepiolite) resulting in a collagen-clay complex which is separated by centrifugation. The interaction primarily occurs with high molecular weight aggregates of the protein as indicated by the fact that collagen from the skin of lathyritic rats interacts to a lesser extent. Thus, when calf skin collagen is fully retained, 45% of protein from lathyritic animals remains in solution. Monomeric forms of collagen remain soluble after short periods of interaction with sepiolite; at 5 minutes, 34% of the calf skin collagen preparation is recovered in apparently monomeric form. In contrast protein-protein interaction produces the complete retention of the total collagen with longer periods of time.