GRAS Screen™ 7 and 8 were developed by Hampton Research for the crystallization of proteins, including monoclonal antibodies.
Each of the chemicals in GRAS Screen 7 and 8 has been used under one or more of the following categories. As (1) a Generally Recognized As Safe (GRAS) substance, (2) a pharmaceutical excipient, (3) a normal physiological constituent, (4) a metabolic byproduct, and/or (5) a Everything Added to Food in the United States (EAFUS) substance.
GRAS Screen 7 samples 9 salts (Ammonium-acetate, chloride, citrate, formate, phosphate, sulfate, tartrate, Potassium phosphate, & Sodium acetate) at 4 concentrations, sampling 8 unique buffers (pH 4.5 to 10.0) as well as 8 buffer controls without salt. GRAS Screen 7 is supplied in a 96 Deep Well block format and is compatible with robotic and multi-channel pipet liquid handling systems. GRAS Screen 7 is compatible with vapor diffusion, free interface diffusion, and microbatch crystallization methods. For research use only.
GRAS Screen 8 samples 5 salts (Sodium - chloride, citrate, formate, phosphate & tartrate) at 4 concentrations, sampling 8 unique buffers (pH 4.5 to 10.0). GRAS Screen 8 is supplied in a 96 Deep Well block format and is compatible with robotic and multi-channel pipet liquid handling systems. GRAS Screen 8 is compatible with vapor diffusion, free interface diffusion, and microbatch crystallization methods. For research use only.
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