It shall be unlawful for the superintendent or business manager of any state agency or institution or any person with authority to purchase supplies, materials or equipment for such state agency or institution, or the spouse or child of either of them, to furnish such supplies, materials or equipment, or be interested by stock ownership or other profit sharing arrangements, in any business entity which is engaged in the furnishing of such supplies, materials or equipment to such agency, department or institution of the State of Oklahoma.