Abstract: There is provided a bioreactor including: a chamber unit having an accommodating space therein; an upper fixing member and a lower fixing member that are disposed at respective planes perpendicular to a central axis of the chamber unit inside the chamber unit and are movable in a central-axis direction of the chamber unit; and a filling layer that is formed in a space between the upper fixing member and the lower fixing member inside the chamber unit and contains a plurality of carriers.

Abstract: A dissolved carbon monoxide sensor includes an electrode and a carbon monoxide dehydrogenase fixed on the electrode. According to this configuration, the dissolved carbon monoxide sensor directly detects a dissolved carbon monoxide concentration in a solution by an enzyme reaction of the carbon monoxide dehydrogenase.