Patent ID: 8350006
Filing Date: 2013-01-08
Classification: G01N

Abstract:
1. A method for preparing a sample of powdered nutritional composition or powdered raw protein source for a HT-2 cell bioassay measuring TGF-β activity, the method comprising: a. reconstituting the sample to a concentration of about 140 mg/mL to about 150 mg/mL; b. centrifuging the reconstituted sample to separate it into a supernatant layer and a pellet and retaining the supernatant layer; c. acidifying the supernatant layer to a pH of about 2 to about 3; d. incubating the supernatant layer for about 15 minutes at room temperature; e. centrifuging the supernatant layer to separate it into a second supernatant layer and a second pellet and retaining the second supernatant layer; f. neutralizing the second supernatant layer from step (e) to a pH of about 7 to about 7.5; g. centrifuging the second supernatant layer from step (f) to separate it into a third supernatant layer and a third pellet and retaining the third supernatant layer; and h. contacting the third supernatant layer with HT-2 cells.