Working with cell lysates would be challenging, because detergents can cause high background. It is possible to titrate the amount of detergent needed to release protein from the cells. The larger aggregates remain insoluble and they can be sedimented by centrifugation and the smaller aggregates can be separated by ultracentrifugation. The detergent, membranes and soluble protein can be washed away and the Proteostat detection reagent can be used on the remaining proteins.