Abstract: A virus inactivation method is provided. The method includes irradiating a solution containing an artificially expressed antibody or antibody fragment with ultraviolet rays in the presence of a radical scavenger. The irradiating only aggregates 5% or less of the antibody or antibody fragment. A wavelength of the ultraviolet rays is 200 nm or longer and 315 nm or shorter. An irradiation amount of the ultraviolet rays is 300 mJ/cm2 or more. An irradiation time of the ultraviolet rays is 3 minutes or less. A concentration of the radical scavenger in the solution is 0.03 mM or more.

Abstract: A culturing process according to the present embodiment includes: a step of carrying out the setting of a culture apparatus 1 (Step S100); a step of carrying out the conditioning of a pH sensor 40 (Step S200); and an actual culturing step (Step S300). More specifically, in the process, the setting of the culture apparatus 1 (Step S100) is carried out; and, after the completion of the preceding step, the step of carrying out the conditioning of the pH sensor 40 (Step S200) is carried out; and subsequently the actual culturing step is carried out using the culture apparatus 1 (Step S300).