... MUC5B, and MUC6 (1–4)—are gel-forming mucins, and it is possiblethat there are others. In isolating a mixture of mucins from mucus, there is consider-able scope for heterogeneity in their mass and ... however, is rate-zonalcentrifugation, which separates molecules not on hydrodynamic volume alone but ontheir mass-to-volume ratio as well. The basis of rate-zonal centrifugation for this pur-pose is ... bytemperature and mechanical instabilities in centrifuges.We first demonstrated the value of rate-zonal centrifugation for the characteriza-tion of cervical mucin heterogeneity and polydispersity (5) and...