The present invention relates to an analytical instrument including: a plurality of electrodes 10, 11 and 12 formed in an annular shape with stacked on one another in an axial direction and a specimen layer formed in an interior of at least one of the plurality of electrodes 10, 11 and 12. The analytical instrument according to the present invention may be configured to include: a first electrode formed in an annular shape a second electrode formed in an annular shape and inserted through an interior of the first electrode with a space from an inner peripheral surface of the first electrode and a specimen layer formed between the inner peripheral surface of the first electrode and an outer peripheral surface of the second electrode.
