| abstract |
A surface portion comprising a base material, a molecule A having a structure derived from guanidine, and a molecule B having a structure derived from at least one molecule selected from the group consisting of glucosamine and lysine, said surface portion Is in contact with at least a part of the base material, and the mass ratio of the molecule A to the molecule B (molecule A: molecule B) is 8: 2 to 4: 6. |