NANOSPHERE, INC. Charter of the Audit Committee of the Board of Directors This Audit Committee Charter (this “Charter”) was adopted by the Board of Directors (the “Board”) of Nanosphere, Inc. (the “Company”) on October 26, 2007. I. PURPOSE The purpose of the Audit Committee (the “Audit Committee”) of the Board is to assist the Board in its oversight of (i) the quality and integrity of the Company’s financial statements and internal controls; (ii) the Company’s cash management policy; (iii) the Company’s compliance with legal and regulatory requirements; (iv) the Company’s overall risk management profile; and (v) the independent auditors’ qualifications, independence and performance. In addition to the powers and responsibilities expressly delegated to the Audit Committee in this Charter, the Audit Committee may exercise any other powers and carry out any other responsibilities as may be required by applicable law, the Nasdaq Stock Market (“Nasdaq”), the Company’s amended and restated certificate of incorporation or amended and restated bylaws, or delegated to it by the Board from time to time. The powers and responsibilities delegated by the Board to the Audit Committee in this Charter or otherwise shall be exercised and carried out by the Audit Committee as it deems appropriate without requirement of Board approval, and any decision made by the Audit Committee (including any decision to exercise or refrain from exercising any of the powers ...