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                                                                    EXHIBIT 10.6

                                                                       EXECUTION

                    INTELLECTUAL PROPERTY TRANSFER AGREEMENT

          This INTELLECTUAL PROPERTY TRANSFER AGREEMENT dated as of September
30, 2005 made by Abbott Laboratories, a corporation organized and existing under
the laws of the State of Illinois and having a principal place of business at
Abbott Park, Illinois 60064 (herein referred to as "Assignor") in favor of ImaRx
Therapeutics, Inc., a corporation organized and existing under the laws of
Delaware and having a principal place of business at Tucson, Arizona 85719
(herein referred to as "Assignee").

          WHEREAS, Assignor owns the patent applications and issued patents
listed on Schedule 1 attached hereto (the "Patents");

          WHEREAS, Assignor owns the trademark and trademark registration listed
on Schedule 2A attached hereto (the "Mark"), and is willing to convey any rights
it may have to the other trademark listed on Schedule 2B hereto (the "Quitclaim
Mark");

          WHEREAS, Assignee desires to acquire the Patents, the Mark, any rights
the Assignor may have to the Quitclaim Mark, and any and all goodwill associated
with the Mark and the Quitclaim Mark;

1)   For good and valuable consideration, the receipt and sufficiency of which
     is hereby acknowledged, Assignor hereby transfers, assigns, and otherwise
     conveys to Assignee, all of Assignor's right, title, and interest in, to,
     and under the following, subject to the limitations described below:

               (a) the Patents, including, without limitation, any
          continuations, divisions, continuations-in-part, reissues,
          reexaminations, extensions or foreign equivalents thereof, and
          including the subject matter of all claims that may be obtained
          therefrom, and all other corresponding rights that are or may be
          secured under the laws of the United States, now or hereafter in
          effect;

               (b) each of the Mark and the Quitclaim Mark, including, without
          limitation, any renewals and extensions thereof, and all other
          corresponding rights that are or may be secured under the laws of the
          United States, now or hereafter in effect;

               (c) the goodwill of the business symbolized by and associated
          with the Mark and the Quitclaim Mark; and

               (d) all proceeds of the assets transferred pursuant to paragraph
          (1), (2), and (3), (collectively, the "Transferred IP", including,
          without limitation, the right to sue for, and collect on, (i) any
          claim by Assignor against third parties for past, present, or future
          infringement of the Patents, and (ii), any claim by Assignor against
          third parties for past, present, or future infringement, dilution,
          disparagement or other unauthorized use of

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          the Mark or the Quitclaim Mark, and (iii) any income, royalties or
          payments due or payable and related exclusively to the Transferred IP
          as of the date of this assignment or thereafter.

2)   Notwithstanding the foregoing, Assignee acknowledges that Assignee will
     become a co-owner of the Patents and will not have exclusive ownership
     rights of the Patents. Assignee expressly acknowledges that Assignor has
     granted, or will have the right to grant, co-ownership rights to the
     Patents to a third party. Assignor and Assignee hereby agree to the
     following covenants with respect to the Patents, and Assignor and Assignee
     hereby agree that each of them shall require that any assignee or successor
     in interest of Assignor's or Assignee's interest in the Patents be bound by
     such covenants.

     a)   Maintenance of the Patents. Each of the co-owners of the Patents (the
          "Co-Owners") shall act cooperatively to maintain the Patents and shall
          pay one-half of all maintenance fees and other costs required to keep
          the Patents in full force and effect.

     b)   Infringement by Third Parties. The Co-Owners shall consult with each
          other prior to filing any action alleging that a third party has
          infringed or misappropriated the right of the Co-Owners under the
          Patents. The Co-Owners may agree to jointly pay for the suit or
          otherwise share such costs and any resulting liability or monetary
          judgment. Except as provided below, if no agreement is reached within
          sixty (60) days, the Co-Owner wishing to file such action may do so,
          but shall pay the entire costs of such action and shall indemnify and
          hold harmless the other Co-Owner from any claim, suit or proceeding
          (including, but not limited to, counterclaims) against such Co-Owner
          arising from the action brought by the other Co-Owner. If only one
          Co-Owner decides to proceed with an action and it prevails, that
          Co-Owner shall be entitled to retain the entire amount of any monetary
          award arising out of that action. To be eligible for the indemnity
          under this section, a Co-Owner must give prompt written notice of any
          claim, suit or proceeding filed or threatened against it and let the
          indemnifying Co-Owner control the defense. If only one Co-Owner files
          an action as provided in this section, the other Co-Owner agrees to
          provide reasonable assistance in such action so long as the suing
          party pays its out-of-pocket expenses.

     c)   Declaratory Judgment Actions. In the event that a declaratory judgment
          action alleging invalidity of any of the Patents, or that use or
          practice of any of the claims in the Patents infringes the patent,
          copyright or trade secrets of others, shall be brought against either
          or both of the Co-Owners, the Co-Owners shall cooperate in good faith
          to determine how best to defend such action. If the Co-Owners cannot
          agree on how to defend any such action, either Co-Owner may on its own
          defend any action brought against it, provided that no settlement,
          consent judgment or other voluntary final disposition may be entered
          into without the consent of the other Co-Owner, which consent shall
          not be unreasonably withheld.

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3)   Assignor hereby permits the Commissioner of Patents and Trademarks to
     record Assignee as the assignee and owner of the Patents and of the Mark
     and Assignor hereby consents to such recordation.

               Assignor shall upon the request of Assignee execute such
documents and take such other actions as Assignee may reasonably request to
evidence and perfect the rights of Assignee in the property conveyed to it
pursuant to this Agreement. The Assignor and Assignee have caused this
Intellectual Property Transfer Agreement to be duly executed and authorized as
of the date hereof.

                                        ABBOTT LABORATORIES


                                        By: /s/Sean E. Murphy
                                            -----------------------------------
                                        Name: Sean E. Murphy
                                        Title: Vice President Global Licensing/
                                               New Business Development


                                        IMARX THERAPEUTICS, INC.


                                        By: /s/Evan Unger
                                            -----------------------------------
                                        Name: Evan Unger
                                        Title: President and CEO