A modified conductive structure includes a conductive substrate and a polymer film disposed over a surface of the polymer film. A chemical bond exists between the polymer film and the conductive substrate, and the polymer film includes repeating units as shown below:






wherein A is an antifouling molecule group; B is a sulfur-containing group or a nitrogen-containing group; R is a single bond or a first linking group; C is -L-E, wherein L is a second linking group, E is an enzyme unit; x and z are each independently 0 or an integer from 1 to 10000, and y is an integer from 1 to 10000; o is 0 or an integer from 1 to 50, and when o is an integer from 1 to 50, m and n are each independently 0 or an integer from 1 to 50.