Comptroller; designation of person to sign instruments. The comptroller may designate, in writing, one or more persons who shall have authority to affix the comptroller’s signature as comptroller to any written instrument that is required to be signed by the comptroller. When the comptroller’s signature is so affixed to a written instrument at the comptroller’s direction, the instrument, in all respects, shall be as binding on the municipality as if signed by the comptroller in person. When the comptroller designates a person for this purpose, however, the comptroller shall notify the corporate authorities to that effect and state in the notice the specific instruments that the person is authorized to sign.