Cell culture medium is critical to cell growth, metabolism, and protein expression. It provides for optimum pH, osmolality, and nutrients in an environment that is essential for cell survival, growth, and expression of proteins and/or metabolites and drug-substance modalities of interest (1). A complete medium typically contains basic nutrients such as carbohydrates, amino acids, lipids, salts, vitamins, trace metals, growth factors/hormones (e.g., insulin), antishear factors, and other chemicals that facilitate cell growth and protein expression and may stabilize recombinant protein…