Any officer or director of any state bank who shall knowingly make or approve a loan in violation of §§ 23-47-501 — 23-47-504 or who shall knowingly permit such a loan to be made, or who shall fail to exercise his or her authority to prevent the making of the loan shall be personally liable to the bank, or to the Bank Commissioner, for the full amount thereof. However, written notice of disapproval of the loan, served on the board of directors and also the commissioner at the time the making or existence of the loan first comes to his or her knowledge, shall relieve any officer or director from personal liability.