The authority is authorized to fix and collect fees, charges, interest and premiums for making, insuring or guaranteeing student loans, purchasing, endorsing or guaranteeing obligations and any other services performed under this chapter. The authority is further authorized to contract with the United States of America or any agency or officer thereof and with any person, partnership, association, banking institution or other corporation respecting the carrying out of the authority’s functions under this chapter. The authority shall at all times endeavor to fix and collect such fees, charges, receipts, premiums and other income so as to have available in the sinking fund at all times an amount which, together with any other funds made available therefor, shall be sufficient to pay the principal of and interest on such bonds as they shall become due and payable and to create reserves for such purposes. Money in the sinking fund, except such part thereof as may be necessary to provide such reserves for the bonds as may be provided for in the resolution authorizing the issuance of such bonds, shall be set aside in the sinking fund at such regular intervals as may be provided in such resolution and is hereby pledged to, and charged with, the payment of the principal of and interest on such bonds as they shall become due and the redemption price or the purchase price of bonds retired by call or purchase as therein provided. Such pledge shall be valid and binding from the time when the pledge is made. The fees, charges, receipts, proceeds and other revenues and moneys so pledged and thereafter received by the authority shall immediately be subject to the lien of such pledge without any physical delivery thereof or further act, and the lien of any such pledge shall be valid and binding as against all parties having claims of any kind in tort, contract or otherwise against the authority, irrespective of whether such parties have notice thereof. The resolution by which a pledge is created need not be filed or recorded except that a record of the proceedings covering the issuance of the bonds shall be filed in the office of the Secretary of State of South Carolina, as required by § 11-15-20. The use and disposition of money to the credit of the sinking fund shall be subject to the provisions of the resolution authorizing the issuance of such bonds. Any such resolution may, in the discretion of the authority, provide for the transfer of surplus money in the sinking fund to the credit of the loan fund. Except as may otherwise be provided in such resolution, such sinking fund shall be a fund for all such bonds without distinction or priority.