AMENDMENT TO AMENDED AND RESTATED LOAN AND SECURITY AGREEMENT

4.                                      The following is added as a new Section 6.12 of the Agreement as follows:

6.12                           Equity Event.  Borrower shall have received on or before March 31, 2011 gross proceeds of at least $5,000,000 from the sale and issuance of its equity or subordinated debt securities to investors reasonably acceptable to Bank.

5.                                      Borrower acknowledges and agrees that no Advances shall be made under Section 2.1(a) of the Agreement until Borrower has complied with Sections 6.11(a) and (b), and any future Advances made pursuant to Section 2.1(a) of the Agreement shall be subject to Section 3.2 of the Agreement.

6.                                      Exhibit D to the Agreement is replaced in its entirety with the Exhibit D) attached hereto.

7.                                      Unless otherwise defined, all initially capitalized terms in this Amendment shall be as defined in the Agreement. The Agreement, as amended hereby, shall be and remain in full force and effect in accordance with its respective terms and hereby is ratified and confirmed in all respects.  Except as expressly set forth herein, the execution, delivery, and performance of this Amendment shall not operate as a waiver of, or as an amendment of, any right, power, or remedy of Bank under the Agreement, as in effect prior to the date hereof.  Borrower ratifies and reaffirms the continuing effectiveness of all agreements entered into in connection with the Agreement.

8.                                      Borrower represents and warrants that the representations and warranties contained in the Agreement are true and correct as of the date of this Amendment, and that no Event of Default has occurred and is continuing.

9.                                      This Amendment may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one instrument.

10.                               As a condition to the effectiveness of this Amendment, Bank shall have received, in form and substance satisfactory to Bank, the following:

(a)                                  this Amendment duly executed by Borrower;

(b)                                 

(c)                                  a default fee equal to $2,500, plus an amount equal to all Bank Expenses incurred through the date of this Amendment, and

(d)                                  such other documents, and completion of such other matters, as Lender may reasonably deem necessary or appropriate.

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IN WITNESS WHEREOF, the undersigned have executed this Amendment as of the first date above written.

EXHIBIT D
COMPLIANCE CERTIFICATE

The undersigned authorized officer of Singulex, Inc. hereby certifies that in accordance with the terms and conditions of the Amended and Restated Loan and Security Agreement dated May 15, 2007 between Borrower and Bank, as amended from time to time (the “Agreement”), (i) Borrower is in complete compliance for the period ending            with all required covenants except as noted below and (ii) all representations and warranties of Borrower stated in the Agreement are true and correct as of the date hereof.  Attached herewith are the required documents supporting the above certification.  The Officer further certifies that these are prepared in accordance with Generally Accepted Accounting Principles (GAAP) and are consistently applied from one period to the next except as explained in an accompanying letter or footnotes.

Please indicate compliance status by circling Yes/No under “Complies” column.

Comments Regarding Exceptions: See Attached.