Monitoring utilizations of amino acids and vitamins in culture media and Chinese hamster ovary cells by liquid chromatography tandem mass spectrometry

•A LC/MS/MS method was developed to quantify 30 metabolites in media and CHO cells.•Essential and non-essential amino acids were separated by fed-batch feeding.•Ten essential amino acids showed a zig–zag pattern in response to feeding.•Seven non-essential amino acids showed smoother profiles with wide changes.•Five vitamins accumulated but 4 changed little during a culture period.