Method for determining undifferentiated state of pluripotent stem cells by culture medium analysis

A method for automatically determining an undifferentiated state of pluripotent stem cells in order to subculture the pluripotent stem cells, comprising:

• automatically determining, using a computer, whether pluripotent stem cells are in an undifferentiated state or not based on a time-dependent change in a variation value of an extracellular metabolite contained in a culture medium in which the pluripotent stem cells are cultured, in order to remove or maintain the pluripotent stem cells based on determination results in the automatically determining whether the pluripotent stem cells are in the undifferentiated state or not, wherein the pluripotent stem cells are removed when the pluripotent stem cells are determined as not being in the undifferentiated state and the pluripotent stem cells are maintained when the pluripotent stem cells are determined as being in the undifferentiated state, in order to perform the automated subculture of the pluripotent stem cells,
• wherein the extracellular metabolite is at least one selected from a group consisting of L-glutamic acid, L-alanine and ammonia, and
• wherein a type of the culture medium is a culture medium configured to maintain the undifferentiated state of the pluripotent stem cells, and
• wherein the variation value is found as a ratio of a variation amount of the L-glutamic acid, the L-alanine or the ammonia to a variation amount of L-lactic acid which is a further extracellular metabolite contained in the culture medium.