COLLOIDAL SILICA-ALUMINUM MODIFIED-PVP DENSITY GRADIENT CENTRIFUGATION - CENTRIFUGE TUBE WALL CELL ADHERENCE, AGGREGATION, SEPARATION PROPERTIES AND COMPARISON TO BSA AND FICOLL

A method is described for the inexpensive and easy preparation of colloidal silica-aluminum modified-polyvinylpyrrolidone (CS-AM-PVP) density gradient centrifugation medium. Using density gradient centrifugation, several cell separation and biochemical characteristics were studied: centrifuge tube wall cell adherence, mouse spleen cell density distribution, rebanding properties, mitogen response and cell aggregation. Cell adherence to the centrifuge tube wall using density gradients of CS-AM-PVP was compared with density gradients of bovine serum albumin and Ficoll. Few cells adhered to the centrifuge tube wall when CS-AM-PVP was used as a gradient medium; whereas, significant cell adherence to the centrifuge tube wall occurred when bovine serum albumin of Ficoll was used as a gradient medium. The CS-AM-PVP gradient medium did not inhibit the response to mitogens of mouse spleen cells which had been separated into density subpopulations in a discontinuous CS-AM-PVP density gradient, caused a minimum amount of cell aggregation, and was found to be non-toxic. © 1979.