Patent ID: 7321831

Claim:
An electrode assembly, comprising: an electrode; a multi-component self-assembled monolayer of two or more different components formed on the electrode; and a nucleic acid fragment fixed on the surface of the monolayer by a covalent bond via a bifunctional linking molecule, wherein said bifunctional linking molecules does not comprise a nucleic acid, and wherein the monolayer is composed of at least two components represented by the following formula (1) with the type of J n being different: q n -R n -J n (1) wherein q n represents a group which is chemically bound to or adsorbed on the electrode, R n represents a linking group, J n represents different functional groups of n types, and n represents an integer of 2 or more, and in the components of formula (1) of n types, q n and R n may be identical or different from each other, and J n are different from each other; wherein the bifunctional linking molecule is represented by the following formula (2): X 1 -L 1 -X 2 (2) wherein X 1 represents a group which forms a covalent bond with at least one type of the functional group J n in the above formula (1), X 2 represents a group which forms a covalent bond with a functional group Z in the following formula (3), and L 1 represents a linking group; and wherein the nucleic acid fragment is represented by the following formula (3): Z-L 2 -Nc (3) wherein Z represents a group which forms a covalent bond with the group X 2 in the above formula (2), Nc represents a nucleic acid fragment, and L 2 represents a linking group.