Patent ID: 8916389

Claim:
A sensor element for surface plasmon resonance (SPR) measurement utilizing an SPR effect, wherein the sensor element comprises: a transparent substrate; a gold thin film formed on at least a part of the transparent substrate; and a thin film with affinity for a sample provided on the transparent substrate having the gold thin film formed on at least a part thereof; wherein the transparent substrate having the gold thin film and the thin film with affinity for a sample provided thereon has a measurement region (region A), a sample introduction section (region B) and a sample absorption section (region C) being provided with the region A therebetween, the three regions A, B, and C being located at different portions from each other on the transparent substrate so as to not overlap each other, wherein the thin film with affinity for a sample is provided on at least a part of the surface in all the regions A, B, and C, the thin film with affinity for a sample in the region A is provided with a sample measurement section containing a molecule-recognizing film, an introduction port is formed on the film with affinity for a sample in the region B, and an absorption pad is provided on the film with affinity for a sample in the region C so that the whole region C is covered, wherein the sample measurement section comprises: a first portion comprising an immobilized first molecule-recognizing material, a molecule of which forms a first molecular complex with a first molecule of the sample to be measured, the first portion being located on a first narrowed region; and a second portion comprising an immobilized second molecule-recognizing material, a molecule of which forms a second molecular complex with a second molecule of the sample to be measured, the second portion being located on a second narrowed region separated from the first narrowed region, wherein a point in the region B, a point in the first portion of the sample measurement section of region A, and a point in the region C exist in a first straight line on the thin film with affinity for a sample, such that a second straight line connecting the first and second portions of the sample measurement section is substantially perpendicular to the first straight line, and wherein the surface of the thin film with affinity for a sample in the region A is covered with a film without affinity for a sample.