If articles or products are purchased by a local governmental agency or a state agency from an institution or organization approved for a grant-in-aid under this act, the secretary for children and families may request waiver of competitive bid requirements and in the case of state agencies the director of purchases is authorized to waive such conditions if he determines that it would be in the public interest to negotiate at current supply prices. All such purchases by state agencies shall be made through the division of purchases of the state department of administration.