Abstract: A method and a kit for cell culture clarification, as well as a system or apparatus for clarifying a cell culture and purifying biomolecules of interest, are described. The cell culture comprises at least one biomolecule of interest. The method comprises adding one or more compounds to the cell culture that allow the formation of floccules of solutes and/or particulates in said cell culture harvest, adding an amount of diatomaceous earth (DE) to said cell culture harvest, agitating the obtained solution, and transferring said solution to a filtration vessel comprising a support filter having a surface, whereby the diatomaceous earth in said solution forms a layer on said surface and filtering said harvest solution through said layer and support filter.

Abstract: The invention provides a method and a kit for combined virus inactivation and capture/purification of a feed containing a protein of interest. The method comprises the steps of: contacting a feed comprising a protein of interest with negatively charged particles or media, conditioning the particles or media such that the pH is acidic thereby inactivating said virus, and eluting said protein of interest.