A self assembling monolayer formed by the self assembling molecules is caused to bond onto the surface of a base material, and chelators are caused to bond onto the self assembling monolayer, to produce a substrate, in which the chelators are bound to the self assembling monolayer at a density within a range from 0.4/nm.sup.2 to 4/nm.sup.2. The bonding of the chelators onto the self assembling monolayer being performed within an organic solvent.