All money of the council, except as otherwise authorized or provided in the Hospital Equipment Loan Act or in a bond resolution, trust agreement or other instrument under which bonds are issued, shall be deposited as soon as practical in a separate account or accounts in banks or trust companies organized under the laws of this state or in national banking associations. All deposits of money shall, if required by the council, be secured in such a manner as the council determines to be prudent. Banks or trust companies are authorized to give security for the deposits of the council.