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                                                                   Exhibit 10.13

                                LICENSE AGREEMENT

     THIS AGREEMENT is made by and between the Board of Trustees of the
University of Arkansas acting for and on behalf of the UNIVERSITY OF ARKANSAS
FOR MEDICAL SCIENCES, a public institution of higher education having principal
offices at 2404 North University Avenue, Little Rock, Arkansas 72207 United
States of America (hereinafter "UNIVERSITY"), and IMARX THERAPEUTICS, INC.
having a principal place of business at 1635 East 18th Street, Tucson, Arizona
85719 (hereinafter "LICENSEE").

                                 WITNESSETH

     WHEREAS, UNIVERSITY is the owner of certain PATENT RIGHTS (as later defined
herein) relating to certain technology invented by UNIVERSITY employees and
students of the UNIVERSITY and has the right to grant licenses under said PATENT
RIGHTS; and

     WHEREAS, UNIVERSITY desires to have the PATENT RIGHTS developed and
commercialized to benefit the public and is willing to grant licenses there
under; and

     WHEREAS, LICENSEE desires to obtain a license under the PATENT RIGHTS upon
the terms and conditions hereinafter set forth.

     NOW, THEREFORE, in consideration of the premises and the mutual covenants
contained herein, the Parties hereto agree as follows:

                           ARTICLE 1 - EFFECTIVE DATE

     This Agreement shall be effective as of February 10, 2006 (hereinafter the
"EFFECTIVE DATE").

                             ARTICLE 2 - DEFINITIONS

     For the purposes of this Agreement, the following words and phrases shall
have the following meaning:

2.1 "PATENT RIGHTS" shall mean all of the following UNIVERSITY intellectual
property:


                               Page 1 of 18

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     (a) the United States and foreign patents and/or patent applications listed
     in Appendix A attached hereto, and corresponding foreign patents and/or
     foreign patent applications; and

     (b) United States patents issued from the applicatians listed in Appendix A
     and from applications for divisionals, continuations,
     continuations-in-part, reexaminations and reissues of the patents and/or
     applications listed in Appendix A and any divisionals, continuations,
     continuations-in-part, re-examinations and reissues issued from such
     applications and foreign patents issued from corresponding foreign: patent
     applications.

     (c) As used in this Agreement, the term "patent" means (i) unexpired
     letters patent (including inventor's certificates) including, without
     limitation, any substitution, extension (such as supplementary protection
     certificates), registration, confirmation, reissue, re-examination.
     renewal, or any like filing thereof, and (ii) pending applications for
     letters patent, including without limitation any continuation, division or
     continuation-in-part thereof and any provisional applications, and any
     foreign counterparts and all patents that issue there from.

2.2  "LICENSED PRODUCT" shall mean any product or part thereof which:

     (a) but for the license granted herein would infringe in whole or in part
     upon an issued, unexpired, valid claim or a pending claim contained in the
     PATENT RIGHTS in the country in which any such product or part thereof is
     made, used or sold; or

     (b) is manufactured by using a process or is employed to practice a process
     which, but for the license granted herein, would infringe in whole or in
     part upon an issued, unexpired valid claim or a pending claim contained in
     the PATENT RIGHTS in the country in which any LICENSED PROCESS is used or
     in which such product or part thereof is used or sold.

2.3 A "LICENSED PROCESS" shall mean any process, which is covered in whole or in
part by an issued, unexpired, valid claim, or a pending claim contained in the
PATENT RIGHTS.

2.4 "NET SALES" shall mean the gross revenues received by LICENSEE and its
agents, Affiliates, sublicensees and third parties for the sale of LICENSED
PRODUCTS less: returns, allowances, and discounts actually granted; packing,
insurance, freight out, taxes or excise duties imposed on the transaction (if
separately invoiced); wholesaler discounts and cash discounts. No


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deductions shall be made for commissions paid to individuals regularly employed
by LICENSEE and on its payroll, or for cost of collections. Notwithstanding the
foregoing, Net Sales shall not include any revenues with respect to: (i) any
LICENSED PROCESS or (ii) with respect to any product which is a LICENSED PRODUCT
solely with respect to claims 23 through 26 of US Patent No. 6,945,937, and any
corresponding claims in any other patent included in the PATENT RIGHTS, it being
the intent of the parties that the rights of LICENSEE hereunder with respect to
any LICENSED PROCESS and the foregoing claims shall be royalty free.

2.5 "FIRST COMMERCIAL SALE" shall mean the initial transfer by or behalf of
LICENSEE or its sublicensees of LICENSED PRODUCTS or the initial practice of a
LICENSED PROCESS by or on behalf of LICENSEE or its sublicensees in exchange for
cash or some equivalent to which value can be assigned for the purpose of
determining NET SALES.

2.6 "LICENSEE" is understood to include all of its Affiliates. An Affiliate of
LICENSEE shall mean any corporation or other business entity controlled by,
controlling or under common control with LICENSEE, For this purpose, "control"
means direct or indirect beneficial ownership of at least fifty percent (50%) of
the voting stock, or at least fifty percent (50%) interest in the income of such
corporation or other business.

2.7 "TERRITORY" shall mean the world.

2.8 "LICENSED FIELD" shall mean all applications.

                                ARTICLE 3 - GRANT

3.1 UNIVERSITY hereby grants to LICENSEE an exclusive right and license in the
TERRITORY for the LICENSED FIELD to practice under the PATENT RIGHTS and to
make, have made, use, offer for sell, sell and import LICENSED PRODUCTS and to
practice the LICENSED PROCESSES. Such licenses are hereby granted until the end
of the term of the PATENT RIGHTS unless this Agreement shall be sooner
terminated according to the terms hereof.

3.2 LICENSEE shall have the right to grant sublicenses consistent with this
Agreement provided that LICENSEE shall be responsible for the operations of its
sublicenses relevant to this Agreement as if such operations were carried out by
LICENSEE, including the payment of royalties whether or not paid to LICENSEE by
a sublicensee. LICENSEE further agrees to deliver to UNIVERSITY a true and
correct copy of each sublicense granted to LICENSEE, and


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any modification or termination thereof, within thirty (30) days after
execution, modification, or termination, which University shall maintain in
confidence per the terms of Article 17. Upon termination of this Agreement, any
and all existing sublicenses granted by LICENSEE shall survive and shall be
assigned to UNIVERSITY.

3.3 UNIVERSITY reserves the right to make and to use and to grant nonexclusive
licenses to non-profit entities to make and to use, for research purposes only
and not for any commercial purpose the technology and the subject matter
described and claimed in the PATENT RIGHTS.

                            ARTICLE 4 - DUE DILIGENCE

4.1 LICENSEE shall use commercially reasonable efforts to bring one or more
LICENSED PRODUCTS to market through an active and diligent program for
exploitation of the PATENT RIGHTS and to continue active, diligent marketing
efforts for one or more LICENSED PRODUCTS throughout the life of this Agreement.

4.2 In addition, LICENSEE shall use commercially reasonable efforts to adhere to
the following milestones:

     (a) LICENSEE shall deliver to UNIVERSITY on or before nine (9) months after
     the execution of this Agreement the preliminary business and FDA
     application and approval plans showing each phase of development of
     LICENSED PRODUCTS and shall provide similar reports to UNIVERSITY in
     accordance with Article 6.3 hereof.

     (b) LICENSEE shall develop an animal model / testing protocol of LICENSED
     PRODUCT on or before two years after execution of this Agreement.

     (c) LICENSEE shall proceed diligently toward obtaining appropriate United
     States regulatory approval for marketing LICENSED PRODUCTS and shall show
     appropriate and reasonable evidence toward same within five years of
     entering into Agreement.

4.3 LICENSEE's continued failure to perform in accordance with Articles 4.1 and
4.2 above for a period of 45 days after receiving from UNIVERSITY written notice
of default thereon, shall be grounds for UNIVERSITY, at sole option of
UNIVERSITY, to terminate this Agreement pursuant to Article 10 hereof or render
this license nonexclusive. In making this decision, UNIVERSITY shall take into
account the normal course of such activities conducted with sound


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and reasonable business practices and judgment and shall take into account the
reports provided hereunder by LICENSEE.

                  ARTICLE 5 - ROYALTIES AND OTHER CONSIDERATION

5.1 For the rights, privileges and license granted hereunder, LICENSEE shall pay
royalties and other compensation to UNIVERSITY in the manner hereinafter
provided to the end of the term of the PATENT RIGHTS or until this Agreement
shall be earlier terminated:

     (a) LICENSEE shall pay to UNIVERSITY on or before thirty (30) days after
     the EFFECTIVE DATE one half ($7,500) of a nonrefundable initial license
     fee of fifteen thousand dollars ($15,000) and the balance of $7,500 on or
     before the first anniversary of the EFFECTIVE DATE.

     (b) LICENSEE shall pay to UNIVERSITY twenty-five thousand dollars ($25,00O)
     within thirty (30) days after the FIRST COMMERCIAL SALE in the U.S.

     (c) LICENSEE shall pay to UNIVERSITY a minimum annual royalty in accordance
     with the following schedule:

          (i)  $5,000 per year commencing February 10, 2007, increasing to

          (ii) $7,000 per year on February 10, 2009, and each year thereafter.

     Such minimum royalty payments shall be offset against University Royalties
     due during the applicable year.

     (d) LICENSEE shall pay to UNIVERSITY the following running royalties
     ("UNIVERSITY Royalties"):

          (i)  4.0% of NET SALES of up to $1M;

          (ii) 3.0% of NET SALES greater than $1M, but less than $10M;

          (iii) 2.0% of NET SALES greater than $10M.

     Provided, however, that the total royalty payments paid by LICENSEE to
     UNIVERSITY shall not exceed $20M, and the license granted hereunder shall
     be royalty free after such amount has been paid.


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     (e) A one-time success payment of $250,000 in the first year that the
     aggregate Net Sales of LICENSED PRODUCTS exceeds $10M. This payment shall
     be made in addition to any royalties due.

     (f) Third Party Payments: LICENSEE shall pay UNIVERSITY fifteen percent
     (15%) of lump-sum non-royalty consideration actually received by LICENSEE
     from third party (ies) under a sublicensing agreement with LICENSEE;
     provided that, if LICENSEE has added substantial value or improvement to
     the LICENSED PRODUCTS, LICENSEE shall pay UNIVERSITY seven and one-half
     percent (7.5%) of such consideration. Substantial value or improvement is
     defined as FDA / regulatory approval for marketing LICENSED PRODUCTS. The
     foregoing payment obligation shall not apply with respect to consideration
     related to the provision of goods, services or equity ownership by LICENSEE
     to any sublicensee.

     (g) LICENSEE shall pay one hundred percent (100%) of the costs incurred in
     the preparation, filing, prosecution (including appeals, interferences, and
     other ex parte and inter partes proceedings) and maintenance of patent
     applications and patents by UNIVERSITY as of the EFFECTIVE DATE in
     accordance with the following schedule:

          (i)  $15,000 on the execution of this agreement and

          (ii) The balance of all patent costs incurred prior to the EFFECTIVE
               DATE twelve (12) months from the EFFECTIVE DATE of this
               agreement.

     (h) Should LICENSEE be required to pay royalties to a third party with
     respect to any patent rights of such third party ("Other Royalties") in
     order to make, have made, use, offer for sell, sell or import a particular
     LICENSED PRODUCT, LICENSEE shall be entitled to credit such Other Royalties
     against the UNIVERSITY royalties due hereunder, provided that the
     UNIVERSITY royalties shall not be reduced below fifty percent (50%) of
     those that would otherwise be due UNIVERSITY.

5.2 All amounts payable hereunder by LICENSEE shall be paid in full, without
deduction of taxes or other fees which may be imposed by any government and
which shall be paid by LICENSEE.


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5.3 No multiple or cumulative royalties shall be payable because any LICENSED
PRODUCT or LICENSED PROCESS, its manufacture, use, lease or sale are or shall be
covered by more than one PATENT RIGHTS patent application or PATENT RIGHTS
patent licensed under this Agreement.

5.4 All sales or use of LICENSED PRODUCTS by LICENSEE, excepting sales under
Article 8.1 to an Affiliate or another LICENSEE of UNIVERSITY, shall be subject
to royalty payments as provided.

                         ARTICLE 6 - RECORDS AND REPORTS

6.1 LICENSEE shall keep full, true and accurate books of account containing all
particulars that may be necessary for the purpose of showing the amounts payable
to UNIVERSITY hereunder. Said books of account shall be kept at LICENSEE's
principal place of business or the principal place of business of the
appropriate operating, subsidiary of LICENSEE to which this Agreement relates.
Said books and the supporting data shall be open, to the extent relevant to the
licenses granted hereunder, at all reasonable times for Five (5) years following
the end of the calendar year to which they pertain, to the inspection of
UNIVERSITY or his agents for the purpose of verifying LICENSEE's royalty
statement or compliance in other respects with this Agreement. Should such
inspection lead to the discovery of a greater than ten percent (10%) discrepancy
in reporting to UNIVERSITY's detriment, LICENSEE agrees to pay the full cost of
such inspection actually incurred by UNIVERSITY.

6.2 LICENSEE shall report to UNIVERSITY the date of first sale of a LICENSED
PRODUCT or LICENSED PROCESS in each country within thirty (30) days occurrence.

6.3 Prior to the FIRST COMMERCIAL SALE, LICENSEE shall make annual progress
reports to UNIVERSITY regarding both the milestones listed in Article 4 and
other measures of product development. These reports are due June 30 following
the EFFECTIVE DATE and prior to the FIRST COMMERCIAL SALE.

6.4 After the FIRST COMMERCIAL SALE of a LICENSED PRODUCT or LICENSED PROCESS,
LICENSEE, within sixty (60) days after March 31, June 30, September 30, and
December 31 of each year, shall deliver to UNIVERSITY true and accurate reports,
giving such particulars of the business conducted by LICENSEE and its
sublicensees with respect to the LICENSED PRODUCTS and LICENSED PROCESSES during
the preceding three-month


                                  Page 7 of 18

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period under this Agreement as shall be pertinent to a royalty accounting
hereunder. These shall include at least the following:

     (a)  quantity of LICENSED PRODUCTS manufactured and sold by LICENSEE;

     (b)  quantity of LICENSED PRODUCTS manufactured and sold by each
          sublicensee;

     (c)  total receipts for LICENSED PRODUCTS sold by LICENSEE;

     (d)  total receipts by LICENSEE for LICENSED PRODUCTS sold by each
          sublicensee;

     (e)  receipts for all LICENSED PROCESSES used or sold by LICENSEE

     (f)  receipts for all LICENSED PROCESSES used or sold by each sublicensee;

     (g)  deductions applicable as provided in Article 2.4;

     (h)  amounts due on additional payments from sublicensees under Article
          4.1(b);

     (i)  total royalties due; and

     (j)  names and addresses of each sublicensee of LICENSEE.

6.5 With each such report submitted, LICENSEE shall pay to UNIVERISITY the
royalties and other amounts then due and payable under this Agreement. If no
royalties or other amounts shall be due, LICENSEE shall so report.

                         ARTICLE 7 - PATENT PROSECUTION

LICENSEE shall apply for, seek prompt issuance of and maintain during the term
of this Agreement the PATENT RIGHTS in the United States and in the foreign
countries listed in Appendix A hereto. Appendix A may be amended by verbal
agreement of both Parties, such agreement to be confirmed in writing within ten
(10) days. The prosecution, filing and maintenance of all PATENT RIGHTS patents
and applications shall be the primary responsibility of LICENSEE, including
payment of all costs associated therewith; provided, however, UNIVERSITY shall
have reasonable opportunities to advise LICENSEE and shall cooperate with
LICENSEE in such prosecution, filing and maintenance.


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                ARTICLE 8 - OTHER TRANSFERS OF LICENSED PRODUCTS

8.1 It is anticipated that LICENSEE may supply LICENSED PRODUCTS or LICENSED
PROCESSES to another Licensee of UNIVERSITY for further processing and/or sale
by the Affiliate or sublicensee under PATENT RIGHTS. No royalty shall be payable
by LICENSEE with respect to such LICENSED PRODUCTS, so long as the Affiliate or
sublicensee shall be obligated to pay UNIVERSITY royalty under PATENT RIGHTS on
its use or sales thereof at a rate not less than that set forth in Article 5.1
(a) However, reports made by LICENSEE as provided in Article 6.3 shall list each
such transaction as a non-royalty-bearing sale and identify such Affiliate or
other LICENSEE.

8.2 If a royalty payment has been made to UNIVERSITY for a LICENSED PRODUCT used
by LICENSEE to make another LICENSED PRODUCT, that payment may be deducted by
LICENSEE from any royalty payment which would otherwise be owing with respect to
such resulting LICENSED PRODUCT, and is no event shall LICENSEE be required
under any circumstances to pay royalties in excess of the royalties payable
under this Agreement with respect to any LICENSED PRODUCT.

                            ARTICLE 9 - INFRINGEMENT

9.1 In the event of any action for infringement, or institution of any
proceedings challenging the validity of any of the patents under PATENT RIGHTS
in the LICENSED FIELD, LICENSEE shall have the right, but not the obligation, at
its own expense and in its own name, to prosecute actions or defend proceedings.
UNIVERSITY will assist LICENSEE in actions or proceedings, if so requested, and
will lend its name to actions or proceedings if required by LICENSEE or by law.
LICENSEE will assume all reasonable costs, which UNIVERSITY may incur in
affording assistance in actions or proceedings. If LICENSEE elects not to bring
any action for infringement, or defend any proceedings challenging the validity,
of any of the patents under PATENT RIGHTS as aforesaid, UNIVERSITY shall have
the right but not the obligation to bring action or defend proceedings in its
own name at its own expense. LICENSEE hereby agrees to lend its name to the
proceedings if a legally indispensable party and will render all reasonable
assistance on technical matters relating to the proceedings. In the event of a
recovery with respect to an action for infringement, UNIVERSITY and LICENSEE
shall first be reimbursed for costs of prosecuting or defending the action, and
any balance shall be paid to the Party defending or prosecuting the action.


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9.2 Upon payment by LICENSEE of costs incurred by either LICENSEE or UNIVERSITY
in any action for infringement, or defense of any proceedings challenging the
validity, of any patent under PATENT RIGHTS, LICENSEE may utilize a set-off for
all such litigation costs against royalty owed not to exceed fifty (50) percent
of royalties owed in a given year, with carry-over of set-off to future years of
this Agreement. Any recovery of damages by LICENSEE from each patent enforcement
or defense action shall be first applied to reimburse LICENSEE and UNIVERSITY
for such litigation costs not paid from royalties, then to reimburse UNIVERSITY
for royalties set-off and the balance, if any, to be shared equally.

                         ARTICLE 10 - PRODUCT LIABILITY

10.1 LICENSEE shall at all times during the term of this Agreement and
thereafter, indemnify, defend and hold UNIVERSITY, its trustees, directors,
officers, employees and affiliates, harmless against all claims, proceedings,
demands and liabilities of any kind whatsoever, including legal expenses and
reasonable attorneys' fees, arising out of the death of or injury to any person
or persons or out of any damage to property, or resulting from the production,
manufacture, sale, use, consumption or advertisement of the LICENSED PRODUCTS
and/or LICENSED PROCESSES by or on behalf of LICENSEE or arising from any
obligation of LICENSEE hereunder, excepting only claims that the PATENT RIGHTS
infringe third party intellectual property and any claims arising out of
negligence or willful misconduct of UNIVERSITY, its trustees, directors,
officers, employees and affiliates.

10.2 Prior to the FIRST COMMERCIAL SALE, LICENSEE shall obtain and carry in full
force and effect commercial, general liability insurance, which shall protect
LICENSEE and UNIVERSITY with respect to events, covered by Article 10.1 above.
Such insurance shall be written by a reputable insurance company authorized to
do business in the State of Arkansas, shall list UNIVERSITY as an additional
named insured there under, shall be endorsed to include product liability
coverage and shall require thirty (30) days written notice to be given to
UNIVERSITY prior to any cancellation or material change thereof. The limits of
such insurance shall not be less than one million dollars ($1,000,000) per
occurrence with an aggregate of three million dollars ($3,000,000) for personal
injury or death, and one million dollars ($1,000,000) per occurrence with an
aggregate of three million dollars ($3,000,000) for property damage. LICENSEE
shall provide UNIVERSITY with Certificates of Insurance evidencing the same.

10.3 UNIVERSITY hereby represents and warrants to LICENSEE: (i) that UNIVERSITY
is the owner of the PATENT RIGHTS, and (ii) that UNIVERSITY has the power and
authority to enter into the is Agreement and grant the rights granted hereunder,
and (iii) that to the actual


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knowledge of UNIVERSITY the exercise by LICENSEE of the rights granted pursuant
to this Agreement will not infringe upon the intellectual property rights of any
third party. EXCEPT AS OTHERWISE EXPRESSLY SET FORTH IN THIS AGREEMENT,
UNIVERSITY, ITS TRUSTEES, DIRECTORS, OFFICERS, EMPLOYEES, AND AFFILIATES MAKE NO
REPRESENTATIONS AND EXTEND NO WARRANTIES OF ANY KIND. EITHER EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY. FITNESS FOR A
PARTICULAR PURPOSE, VALIDITY OF PATENT RIGHTS CLAIMS, ISSUED OR PENDING, AND THE
ABSENCE OF LATENT OR OTHER DEFECTS, WHETHER OR NOT DISCOVERABLE. NOTHING IN THIS
AGREEMENT SHALL BE CONSTRUED AS A REPRESENTATION MADE OR WARRANTY GIVEN BY
UNIVERSITY THAT THE PRACTICE BY LICENSEE OF THE LICENSE GRANTED HEREUNDER SHALL
NOT INFRINGE THE PATENT RIGHTS OF ANY THIRD PARTY. IN NO EVENT SHALL UNIVERSITY.
ITS TRUSTEES, DIRECTORS, OFFICERS, EMPLOYEES AND AFFILIATES BE LIABLE FOR
INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, INCLUDING ECONOMIC DAMAGE OR
INJURY TO PROPERTY AND LOST PROFITS, REGARDLESS OF WHETHER UNIVERSITY SHALL BE
ADVISED. SHALL HAVE OTHER REASON TO KNOW, OR IN FACT SHALL KNOW OF THE
POSSIBILITY.

                          ARTICLE 11 - EXPORT CONTROLS

     It is understood that UNIVERSITY is subject to United States laws and
regulations controlling the export of technical data, computer software,
laboratory prototypes and other commodities (including the Arms Export Control
Act, as amended, and the Export Administration Act of 1979), and that its
obligations hereunder are contingent on the compliance with applicable United
States export laws and regulations. The transfer of certain technical data and
commodities may require a license from the cognizant agency of the United States
Government and/or written assurances by LICENSEE that LICENSEE shall not export
data or commodities to certain foreign countries without prior approval of such
agency. UNIVERSITY neither represents that a license shall not be required nor
that, if required, it shall be issued.

                          ARTICLE 12 - NON-USE OF NAMES

     LICENSEE shall not use the name of UNIVERSITY, nor any adaptation thereof,
in any advertising, promotional or sales literature without prior written
consent of UNIVERSITY, except that LICENSEE may state that it is licensed by
UNIVERSITY under one or more of the patents and/or applications comprising the
PATENT RIGHTS.


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                            ARTICLE 13 - ASSIGNMENT

     This Agreement shall not be assigned except with the advance written
consent of UNIVERSITY, provided that no such consent shall be required with
respect to any assignment in connection with any sale, merger or other
transaction involving the transfer of substantially all of the assets of
LICENSEE'S business to which this Agreement relates; provided that such assignee
agrees in writing to be bound by all the terms and conditions of this Agreement.
Failure of assignee to so agree shall be grounds to terminate this Agreement by
UNIVERSITY pursuant to Section 15.2.

                         ARTICLE 14 - DISPUTE RESOLUTION

14.1 Except for the right of either Party to apply to a court of competent
jurisdiction for a temporary restraining order, a preliminary injunction, or
other equitable relief to preserve the status quo or prevent irreparable harm,
any and all claims, disputes or controversies arising under, out of, or in
connection with the Agreement which the Parties shall be unable to resolve
within sixty (60) days shall be mediated in good faith. The Party raising such
dispute shall promptly advise the other Party of such claim, dispute, or
controversy in writing, which describes in reasonable detail the nature of such
dispute. By not later than fifteen (15) business days after recipient has
received such notice of dispute, each Party shall have selected for itself a
representative who shall have the authority to bind such Party and shall
additionally have advised the other Party in writing of the name and title of
such representative. By not later than thirty (30) business days after such
notice of dispute, the Party against whom the dispute shall be raised shall
select a mediation firm and such representatives shall schedule a date with such
firm for a mediation hearing. The Parties shall enter into good faith mediation
and shall share the costs equally. If the representatives of the Parties have
not been able to resolve the dispute within thirty (30) business days after such
mediation hearing, the Parties shall have the right to pursue any other remedies
legally available to resolve such dispute in any court of competent
jurisdiction.

14.2 Notwithstanding the foregoing, nothing in this Article shall be construed
to waive any rights or timely performance of any obligations existing under this
Agreement or the sovereign immunity of the UNIVERSITY or the State of Arkansas.


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                        ARTICLE 15 - TERM AND TERMINATION

15.1 The term of this Agreement shall extend from the EFFECTIVE DATE until
expiration of the last to expire patents under PATENT RIGHTS.

15.2 Upon any breach of, or default under, this License Agreement by LICENSEE,
UNIVERSITY may terminate this License Agreement by ninety (90) days written
notice to LICENSEE. Said notice shall become effective at the end of such period
unless during said period LICENSEE shall cure such defect or default.

15.3 LICENSES shall have the right to terminate this Agreement any time upon
ninety (90) days written notice to UNIVERSITY.

15.4 Upon termination of this Agreement for any cause, nothing herein shall be
construed to release either Party of any obligation matured prior to the
effective date of such termination. LICENSEE may, after the effective date of
such termination, sell all LICENSED PRODUCTS and parts thereof that it may have
on hand at the date of termination, provided that it pays earned royalties
thereon as provided in this Agreement.

             ARTICLE 16 - PAYMENTS, NOTICES AND OTHER COMMUNICATIONS

16.1 Any payment, notice or other communication pursuant to this Agreement shall
be sufficiently made or given on the date of mailing if sent to such Party by
certified first class mail, postage prepaid, addressed to it at its address
below or as it shall designate by written notice given to the other Party:

     LICENSEE:

     ImaRx Therapeutics, Inc.
     1635 East 18th Street
     Tucson, Arizona 85719
     Attention: Greg Cobb, CFO

     UNIVERSITY:

     University of Arkansas for Medical Sciences
     4301 West Markham Street #831
     Little Rock, Arkansas 72205
     Attention: Charles Cook


                                  Page 13 of 18

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     With copy to:

     Williams & Anderson PLP
     Twenty-Second Floor
     111 Center Street
     Little Rock, Arkansas 72201
     Attention: Harold J. Evans

                          ARTICLE 17 - CONFIDENTIALITY

17.1 Each party agrees to protect the Confidential Information of the other
party with at least the same degree of care with which it protects its own
Confidential Information (but in no event less than reasonable care), and not to
use any such information other that in connection with its rights and
obligations under this Agreement. Confidential Information with respect to a
Party, includes all information of any kind whatsoever (and all tangible and
intangible embodiments thereof of any kind whatsoever) which is owned or
controlled by such Party, is disclosed by such Party to the other Party pursuant
to this Agreement, and (if disclosed in writing or other tangible medium) is
marked or identified as confidential at the time of disclosure to the receiving
Party or (if otherwise disclosed) is identified as confidential at the time of
disclosure to the receiving Party. Notwithstanding the foregoing, Confidential
Information of a Party shall not include information which the receiving Party
can establish by written documentation (a) to have been publicly known prior to
disclosure of such information by the disclosing Party to the receiving Party,
(b) to have become publicly known, without fault on the part of the receiving
Party, subsequent to disclosure of such information by the disclosing Party to
the receiving Party, (c) to have been received by the receiving Party at any
time from a source, other than the disclosing Party, rightfully having
possession of and the right to disclose such information free of confidentiality
obligations, (d) to have been otherwise known by the receiving Party free of
confidentiality obligations prior to disclosure of such information by the
disclosing Party to the receiving Party, or (e) to have been independently
developed by employees or agents of the receiving Party without access to or use
of such information disclosed by the disclosing Party to the receiving Party.
The Parties acknowledge that the foregoing exceptions shall be narrowly
construed and that the obligations imposed upon each Party shall be relieved
solely with respect to such Confidential Information of the disclosing Party
which falls within the above exceptions and not with respect to related
portions, other combinations, or characteristics of the Confidential Information
of the disclosing Party including, without limitation, advantages, operability,
specific purposes, uses and the like.


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                              ARTICLE 18 - GENERAL

18.1 Legal Compliance. LICENSEE shall comply with all applicable federal, state
and local laws and regulations in connection with its activities pursuant to
this Agreement.

18.2 Patent Marking. LICENSEE agrees to mark the LICENSED PRODUCTS sold in the
United States with all applicable United States patent numbers. All LICENSED
PRODUCTS shipped to or sold in other countries shall be marked in such a manner
as to conform to the patent laws and practice of the country of manufacture or
sale.

18.3 Exports. It is understood that UNIVERSITY is subject to United States laws
and regulations controlling the export of technical data, computer software,
laboratory prototypes and other commodities (including the Arms Export Control
Act, as amended and the Export Administration Act of 1979), and that its
obligations hereunder are contingent on compliance with applicable United States
export laws and regulations. The transfer of certain technical data and
commodities may require a license from the cognizant agency of the United States
Government and/or written assurances by LICENSEE that LICENSEE shall not export
data or commodities to certain foreign countries without prior approval of such
agency. UNIVERSITY neither represents that a license shall not be required nor
that, if required, it shall be issued.

18.4 Waiver. Neither Party may waive or release any of its rights or interests
in this Agreement except in writing. Failure to assert any right arising from
this Agreement shall not be deemed or construed to be a waiver of such right.

18.5 Integration. This Agreement constitutes the entire agreement between the
Parties relating to the subject matter thereof, and all prior negotiations,
representations, agreements, and understandings are merged into, extinguished
by, and completely expressed by it.

18.6 Effect of Agreement. This Agreement is binding upon the Parties hereto, and
shall inure to the benefit of the Parties, and their respective agents,
attorneys, insurers, employees, representatives, officers, directors, partners,
principals, divisions, indemnitors, indemnitees, parent companies, grandparent
companies, subsidiaries, affiliates, associates, consultants, assigns, heirs,
predecessors, and successors in interest, successor trusts, trustees,
shareholders and any trustee in bankruptcy or debtor in possession.

18.7 Construction and Interpretation. This Agreement and its effect are subject
to and shall be construed and enforced in accordance with the laws of the State
of Arkansas without regard to its


                                  Page 15 of 18
<PAGE>

choice of law principles. The drafting and negotiation of this Agreement have
been participated in by counsel for each of the Parties, and any rule of
construction to the effect that any ambiguity is to be resolved against the
drafting Party shall not be applied to the interpretation of this Agreement.

18.8 Severability. The provisions of this Agreement are severable, and in the
event that any provisions of this Agreement shall be determined to be invalid or
unenforceable under any controlling body of the law, such invalidity or
unenforceability shall not in any way affect the validity or enforceability of
the remaining provisions hereof.

18.9 Representation by Counsel. The Parties hereby acknowledge that counsel has
represented each such Party and that this Agreement has been executed with the
consent and advice of counsel.

18.10 Execution and Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original. All counterparts
together shall constitute one and the same original.

18.11 Authority. Each Party represents and warrants for itself that the
individual executing this Agreement on its behalf is authorized to do so and to
bind the Party on whose behalf he is signing to the terms, obligations and
conditions set forth herein.

18.12 Modification or Amendment. This Agreement may not be modified or amended
except in writing signed by all Parties hereto.

18.13 Further Assurance and Documents. The Parties, and each of them, agree to
execute any and all additional documents and to do all things reasonably
necessary to carry out and implement the provisions of this Agreement.

                <Remainder of this page intentionally left blank>


                                  Page 16 of 18

<PAGE>

     IN WITNESS WHEREOF, the Parties hereto have caused this Agreement to be
executed by their duly authorized representatives.

THE BOARD OF TRUSTEES OF THE            IMARX THERAPEUTICS, INC.
UNIVERSITY OF ARKANSAS


/s/ Ann Kemp                            /s/ Greg Cobb
-------------------------------------   ----------------------------------------
By: Ann Kemp                            By: Greg Cobb
Title: Vice President for               Title: CEO
       Finance and Administration

Date: 2/14/06                           Date: 2/8/06


                                  Page 17 of 18

<PAGE>

                                   APPENDIX A

US, Patent #6,945,937, issued 09/20/05
Inventor: Dr. William Culp, et al.
for "Ultrasound Apparatus and Method for Microbubble Augmented Clot Lysis"

PCT/US2004/028934 filed 09/03/04

Patent Costs $27,815 as of 02/02/06


                                  Page 18 of 18
<PAGE>

                            ImaRx Therapeutics, Inc.
                              1635 East 18th Street
                              Tucson, Arizona 85719

                         Exclusive License Terms Summary

Licensee: ImaRx Therapeutics, Inc. (less than 50 employees)

Effective Date: February 10, 2006

IP: UAMS I03-33 (Culp) U.S. Patent # 6,945,937,
"Ultrasound Apparatus and Method for Microbubble Augmented Clot Lysis"

Co-inventor James D. Wilson, (UALR - 50:50)

National patent filings in-work: Japan, Canada, Europe and Australia.

Licensee Pays 100% of all Patent Costs and takes over all patent prosecution

February 20, 2006, on or before:
     $15,000 - approx. one half patent cost reimbursement (1 of 2)

March 10, 2006
     $7,500 one half initial license fee of fifteen thousand dollars ($15,000)

November 10, 2006
     Preliminary business and FDA application and approval plans

February l0, 2007
     $7,500 balance of license fee
     ~$15,000 balance of all patent costs incurred prior to February 10, 2006
     $5,000 Min Annual royalty, increasing to $7,000 per year on February 10,
     2009

February 10, 2008
     Develop an animal model / testing protocol

February 10, 2009
     $7,000 Min Annual royalty increase and each year thereafter

February 10, 2011
     United States regulatory approval

First Commercial Sale + 30days
     $25,000

Royalties
     4.0% of NET SALES of up to $1M;
     3.0% of NET SALES greater than $1M, but less than $10M;
     2.0% of NET SALES greater than $10M
     Total royalty payments paid capped at $20M

<PAGE>

Success payment - one time payment of $250,000 in the first year that the
     aggregate Net Sales exceeds $10M. This payment shall be made in addition to
     any royalties due.

Third Party Payments:
     15% of consideration received by LICENSEE from third parties under a
     sublicensing agreement

     7.5% after FDA/regulatory approval.

Reports:

     June 30, 2006 and prior to the FIRST COMMERCIAL SALE, annual progress
     reports

     After the first commercial sale, within sixty (60) days after March 31,
     June 30, September 30, and December 31 of each year