EXHIBIT 10.28  AMENDMENT NO. 2 TO LEASE  This Amendment No. 2 to Lease (this Amendment
No. 2) is made as of the 11th day of March, 2009, by and
between EDISON SPECTRUM PARTNERS, LLC, a California limited liability company (Lessor) and CombiMatrix Molecular
Diagnostics, Inc., a California Corporation, (Lessee).  This Amendment No. 2 amends and modifies
the terms and conditions of that certain Standard Industrial/Commercial
Multi-Tenant Net Lease dated June 26, 2006 (the Original
Lease), and Amendment No. 1 dated July 7, 2007 by and
between Lessor and Lessee.  The Original
Lease, as hereby amended, is referred to herein as the Lease.  Capitalized terms which are not otherwise
defined in this Amendment No. 2 shall have the meanings ascribed to such
terms in the Original Lease.  RECITALS  A.    Lessor and Lessee previously
entered into the Original Lease and Amendment No. 1, which sets forth the
terms and conditions relating to Lessees occupancy of certain space, located
at 310 Goddard, Suite 150 and at 300 Goddard, Suite 150, Irvine,
California (the Premises).  B.    Lessor and Lessee now desire
to amend the Original Lease and Amendment No.1 to (i) extend the Term.  AGREEMENT  FOR VALUABLE CONSIDERATION,
the receipt and sufficiency of which is hereby acknowledged, Lessor and Lessee
hereby agree as follows:  1.             Extension of Term.  The Original Term is hereby extended for a
period of six months commencing on August 1, 2009 and ending January 31,
2010 (the Extension Term).  2.             Base Rent.  The Base
Rent of the extension term shall remain the same as in Amendment No. 1 as
shown:  Lease  310 Goddard, Suite 150:  Months
  of Term
  
  Rentable
  Square Feet
  
  Rent Per Square
  Foot Per Month
  
  Monthly
  Base RentAugust 1,2009-January 
  31, 2010
  
  3,625
  
  $
  2.05
  
  $
  7,431.25  300 Goddard, Suite 150:  Months
  of Term
  
  Rentable
  Square Feet
  
  Rent Per Square
  Foot Per Month
  
  Monthly
  Base RentAugust 1,2009-January
  31, 2010
  
  3,148
  
  $
  2.05
  
  $
  6,453.40  3.             First Months Base Rent.  The first months Base Rent for the Extension
Term shall be due and payable on or before August 1, 2009.  4.             Effect of Amendment.  Lessor and Lessee acknowledge that the
Original Lease, as hereby amended, remains in full force and effect in
accordance with its terms.


5.             Counterparts.  If this Amendment No. 2 is executed in
counterparts, each is hereby declared to be an original; all, however, shall
constitute but one and the same agreement.  6.             Corporate and Partnership Authority.  If Lessee is a corporation or partnership,
each individual executing this Amendment No. 2 for the corporation or
partnership represents that he or she is duly authorized to execute and deliver
this Amendment No. 2 on behalf of the corporation or partnership and that
this Amendment No. 2 is binding upon the corporation or partnership in
accordance with its terms.  EXECUTION  IN WITNESS WHEREOF, Lessor and Lessee have
executed this Amendment No. 2 as of the date first written above.  Executed at:
  Irvine,
  California
  
  Executed at:
  Mukilteo,
  Washingtonon:
  March 12,
  2009
  
  on:
  March 12,
  2009By LESSOR:
  
  By LESSEE:EDISON SPECTRUM PARTNERS, LLC,
  
  COMBIMATRIX MOLECULAR DIAGNOSTICS, INC,a California
  limited liability company
  
  a California
  CorporationBy:
  Thomas Falcon,
  
  By:
  Scott R.
  Burellits member
  
  
  Chief
  Financial OfficerBy:
  /s/
  THOMAS FALCON
  
  
  By:
  /s/ SCOTT R. BURELLIts:
  Member
  
  
  Its:
  CFO