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                                                                    EXHIBIT 10.7

                                                                       EXHIBIT H

                            IMARX THERAPEUTICS, INC.

                   SERIES E PREFERRED STOCK PURCHASE AGREEMENT

     This Series E Preferred Stock Purchase Agreement (this "Agreement") is
entered into as of the date set forth below between ImaRx Therapeutics, Inc., a
Delaware corporation (the "Company") and Abbott Laboratories, an Illinois
corporation (the "Purchaser"). The parties hereby agree as follows:

                                   SECTION 1

                      AUTHORIZATION AND SALE OF SECURITIES

     1.1 AUTHORIZATION. The Company has, or before the Closing (as defined in
Section 2.1) will have, duly authorized the sale and issuance pursuant to the
terms and conditions hereof of shares of its Series E Preferred Stock (the
"Shares") having the rights, restrictions, privileges and preferences set forth
in the Certificate of Designation of Rights, Preferences and Privileges of
Series E Preferred Stock to be filed with the Delaware Secretary of State in
substantially the form attached hereto as Exhibit A (the "Designations").

     1.2 SALE OF SECURITIES. Subject to the terms and conditions hereof, at the
Closing, the Company will issue and sell to the Purchaser, and the Purchaser
agrees to purchase from the Company, One Million (1,000,000) Shares as partial
consideration for the Company's purchase of certain assets from Purchaser
pursuant to that certain Asset Purchase Agreement between the parties dated
September 30, 2005 (the "Asset Purchase Agreement").

                                   SECTION 2

                                CLOSING; DELIVERY

     2.1 CLOSING. The closing of the purchase by the Purchaser and the sale by
the Company of the Shares (the "Closing") shall be held at the offices of DLA
Piper Rudnick Gray Cary US LLP, counsel to the Company, at 701 Fifth Avenue,
Suite 7000, Seattle, WA 98104, on the date of closing of the transactions
contemplated by the Asset Purchase Agreement (the "Closing Date").

     2.2 DELIVERY. At the Closing, the Company will issue to the Purchaser a
certificate in the Purchaser's name representing the Shares purchased by the
Purchaser.


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                                    SECTION 3

                  REPRESENTATIONS AND WARRANTIES OF THE COMPANY

     The Company hereby represents and warrants to the Purchaser as follows:

     3.1 ORGANIZATION AND STANDING. The Company is a corporation duly organized
and existing under the laws of the State of Delaware. The Company has the
requisite corporate power to own and operate its properties and assets.

     3.2 CORPORATE POWER. The Company has all requisite corporate power to enter
into this Agreement, to sell the Shares hereunder and to carry out and perform
its other obligations under the terms of this Agreement.

     3.3 CAPITALIZATION. As of the date of this Agreement, the capitalization of
the Company consists of the following:

          (a) Common Stock. A total of 20,000,000 authorized shares of Common
Stock, of which 8,943,532 shares were issued and outstanding. All of the
outstanding shares of Common Stock have been duly authorized, fully paid and are
nonassessable.

          (b) Preferred Stock. A total of 15,000,000 authorized shares of
Preferred Stock, consisting of 2,400,000 shares designated Series A Preferred
Stock, 2,291,144 of which were issued and outstanding; 800,000 shares designated
Series B Preferred Stock, 593,226 of which were issued and outstanding;
1,700,000 shares designated Series C Preferred Stock, 285,714 of which were
issued and outstanding; 545,500 shares designated Series D Preferred Stock,
438,232 of which were issued and outstanding; and 1,000,000 shares designated
Series E Preferred Stock, none of which are issued and outstanding. All of the
outstanding shares of Preferred Stock have been duly authorized, fully paid and
nonassessable and issued in compliance with all applicable federal and state
securities laws.

          (c) Proposed Increase in Authorized Capital. The Company plans to seek
stockholder approval of a substantial increase in the number of authorized
shares of its Common Stock and Preferred Stock in order to ensure the
availability of an adequate number of shares to cover: (i) the conversion of the
Secured Convertible Promissory Notes in the aggregate principal amount of
$4,000,000 and the exercise of the related Warrants issued pursuant to that
certain Secured Note and Warrant Purchase Agreement dated September [29], 2005,
(ii) the reservation of an adequate number of shares of Common Stock for
issuance upon conversion of the Shares, (iii) an increase the number of shares
available for issuance pursuant to the Company's 2000 Stock Plan by 2,000,000
shares, to an aggregate of 5,000,000 shares, (iv) the possible exercise by the
Company and the placement agent in the Company's current Common Stock offering
of the right to exercise a 25% over-subscription option to offer an additional
625,000 shares in such offering, and (v) possible future strategic transactions
and future equity financings. The exact number of authorized shares for which
the Company will seek stockholder approval has not yet been determined.

     3.4 OTHER SECURITIES. The Company has reserved 3,000,000 shares of its
Common Stock for issuance to service providers of the Company, of which
2,603,200 shares are subject to


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options that are currently outstanding. In addition, there are outstanding
warrants to purchase 1,211,404 shares of Common Stock and 10,909 shares of
Series A Preferred Stock. The Company has or will issue Secured Convertible
Promissory Notes in the aggregate principal amount of $4,000,000 and warrants to
purchase up to 100,000 shares of Common Stock in connection with a bridge
financing to close immediately prior to the closing of the transactions pursuant
to the Asset Purchase Agreement. There are currently 2,395,686 shares of Common
Stock issuable upon conversion of outstanding shares of Series A Preferred
Stock, 1,035,073 shares of Common Stock issuable upon conversion of outstanding
shares of Series B Preferred Stock, 295,858 shares of Common Stock issuable upon
conversion of outstanding shares of Series C Preferred Stock, and 602,570 shares
of Common Stock issuable upon conversion of outstanding shares of Series D
Preferred Stock. The Company is currently offering for sale up to an aggregate
of 2,500,000 shares of Common Stock, and will issue a warrant to purchase up to
250,000 shares of Common Stock to the placement agent in such offering if the
maximum amount is sold in the offering. An additional 625,000 shares of Common
Stock might be issued in the Company's current Common Stock offering, and the
placement agent may receive a warrant to purchase up to an additional 62,500
shares of Common Stock, if the Company and the placement agent exercise an
over-subscription option. Except as set forth in this Section 3.4, the Company
has no obligation (contingent or otherwise) to (i) issue any subscription,
warrant, option, convertible security or other such right or to issue or
distribute to holders of any shares of its capital stock any evidences of
indebtedness of the Company or (ii) purchase, redeem or otherwise acquire any
shares of its capital stock or any interest therein or to pay any dividend or
make any other distribution in respect thereof.

     3.5 AUTHORIZATION.

          (a) All corporate action on the part of the Company necessary for the
authorization, execution, delivery and performance of this Agreement, and the
authorization, sale, issuance and delivery of the Shares and the performance of
the Company's obligations hereunder has been taken or will be taken prior to the
Closing.

          (b) This Agreement, when executed and delivered by the Company,
constitutes a valid and binding obligation of the Company enforceable in
accordance with its terms, subject to (i) laws of general application relating
to specific performance, injunctive relief or other equitable remedies, and (ii)
applicable bankruptcy, insolvency, reorganization or other laws of general
application relating to or affecting the enforcement of creditors' rights
generally.

          (c) When issued, sold and delivered in accordance with the terms of
this Agreement for the consideration provided for herein, the Shares will be
duly authorized, validly issued, fully paid and non-assessable, and free of any
liens or encumbrances other than restrictions on transfer under this Agreement
and applicable state and federal securities laws. The shares of Common Stock
issuable upon conversion of the Shares (the "Conversion Shares"), upon issuance
in accordance with the terms of the Designations, will be duly authorized,
validly issued, fully paid and non-assessable, and free of any liens or
encumbrances other than restrictions on transfer under this Agreement and under
applicable state and federal securities laws.


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     3.6 DISCLOSURE. The Company has fully provided the Purchaser with all
information which the Purchaser has requested for deciding whether to purchase
the Shares and all information which the Company believes is reasonably
necessary to enable the Purchaser to make such a decision. Neither this
Agreement nor any other statement or certificate made or delivered in connection
with the Agreement and the transactions contemplated hereby contains any untrue
statement of a material fact or omits to state a material fact necessary not to
make the statements herein untrue or misleading.

     3.7 SECURITIES LAW EXEMPTION. Based in part on the accuracy of the
representations and warranties of the Purchaser contained in Section 4 hereof,
the offer, sale and issuance of the Shares is and will be exempt from the
registration requirements of the Securities Act of 1933, as amended, and the
registration, permit or qualification requirements of any applicable state
securities laws. The Company has not taken any action that would preclude
reliance upon such exemption, including any general solicitation. The Purchaser
acknowledges that, in making the foregoing representation, the Company has
relied upon the Purchaser's representations and warranties set forth in this
Agreement to qualify for such exemptions from registration.

                                    SECTION 4

                   REPRESENTATIONS AND WARRANTIES OF PURCHASER

     The Purchaser hereby represents and warrants as follows:

     4.1 AUTHORIZATION.

          (a) All corporate actions on the part of the Purchaser necessary for
the authorization, execution, delivery and performance of this Agreement, has
been taken or will be taken prior to the Closing.

          (b) This Agreement, when executed and delivered by the Purchaser,
constitutes a valid and binding obligation of the Purchaser enforceable in
accordance with its terms, subject to (i) laws of general application relating
to specific performance, injunctive relief or other equitable remedies, and (ii)
applicable bankruptcy, insolvency, reorganization or other laws of general
application relating to or affecting the enforcement of creditors' rights
generally.

     4.2 INVESTMENT. The Purchaser is acquiring the Shares and the Conversion
Shares (collectively, the "Securities") for investment for the Purchaser's own
account and not with the view to the public resale or distribution thereof
within the meaning of the Securities Act, and the Purchaser has no present
intention of selling, granting any participation in, or otherwise distributing
the Securities. No other person has a direct or indirect beneficial interest, in
whole or in part, in such Securities. The Purchaser understands that the
Securities have not been registered under the Securities Act by reason of a
specific exemption thereunder, which depends upon, among other things, the bona
fide nature of the Purchaser's investment intent as expressed herein.

     4.3 RESTRICTIONS ON TRANSFER. The Purchaser acknowledges that the
Securities must be held indefinitely unless subsequently registered under the
Securities Act or the Company receives an opinion of counsel satisfactory to the
Company that such registration is not required.


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The Purchaser is aware of the provisions of Rule 144 promulgated under the
Securities Act which permit limited resale of stock purchased in a private
placement subject to the satisfaction of certain conditions, including, among
other things, the existence of a public market for the stock, the availability
of certain current public information about the Company, the resale occurring
not less than one year after a party has purchased and paid for the stock to be
sold, the sale being through a "broker's transaction" or a transaction directly
with a "market maker" and the number of shares of the stock being sold during
any three-month period not exceeding specified limitations. The Purchaser
further acknowledges and understands that the Company may not be able to satisfy
the current public information requirement of Rule 144 at the time the Purchaser
wishes to sell the Securities and, if so, the Purchaser would be precluded from
selling the Securities under Rule 144 even if the one year minimum holding
period has been satisfied. There is no assurance that any exemption from
registration under the Securities Act will be available or, if available, will
allow such person to dispose of, or otherwise transfer, all or any portion of
the Securities.

                                    SECTION 5

                CONDITIONS TO PURCHASER'S OBLIGATIONS AT CLOSING

     The obligations of the Purchaser under this Agreement are subject to the
fulfillment or waiver, on or before the Closing, of each of the following
conditions:

     5.1 REPRESENTATIONS AND WARRANTIES TRUE. Each of the representations and
warranties of the Company contained in Section 3 shall be true and correct in
all material respects when made, and as of the Closing Date with the same effect
as though such representations and warranties had been made on and as of the
Closing Date.

     5.2 PERFORMANCE OF OBLIGATIONS; CONSENTS AND WAIVERS. The Company shall
have performed and complied in all material respects with all agreements,
obligations and conditions contained in this Agreement and the Asset Purchase
Agreement that are required to be performed or complied with by it on or before
the Closing Date and shall have obtained all approvals, consents and
qualifications necessary to complete the purchase and sale described herein.

     5.3 DESIGNATIONS EFFECTIVE. The Designations shall have been duly adopted
by the Company by all necessary corporate action of its Board of Directors, and
shall have been duly filed with and accepted by the Secretary of State of the
State of Delaware.

     5.4 SECURITIES EXEMPTIONS. The offer and sale of the Securities to the
Purchaser pursuant to this Agreement shall be exempt from the registration
requirements of the Securities Act, and the registration and/or qualification
requirements of all applicable state securities laws.

     5.5 CLOSING OF ASSET PURCHASE AGREEMENT. The parties will have consummated
and closed the transactions contemplated by the Asset Purchase Agreement.


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                                    SECTION 6

                 CONDITIONS TO COMPANY'S OBLIGATIONS AT CLOSING

     The Company's obligation to sell and issue the Shares at the Closing is
subject to the fulfillment of the following conditions, any of which may be
waived by the Company:

     6.1 REPRESENTATIONS AND WARRANTIES. The representations and warranties made
by each Purchaser in Section 4 hereof shall have been true and correct when made
and shall be true and correct on the Closing Date as if made on and as of such
Closing Date.

     6.2 PERFORMANCE OF OBLIGATIONS; CONSENTS AND WAIVERS. The Purchaser shall
have performed and complied in all material respects with all agreements,
obligations and conditions contained in this Agreement and the Asset Purchase
Agreement that are required to be performed or complied with by it on or before
the Closing Date and shall have obtained all approvals, consents and
qualifications necessary to complete the purchase and sale described in the
Asset Purchase Agreement.

     6.3 CONSENTS AND WAIVERS. The Company shall have obtained any and all
consents and waivers necessary or appropriate for consummation of the
transactions contemplated by this Agreement.

     6.4 DESIGNATIONS EFFECTIVE. The Designations shall have been duly adopted
by the Company by all necessary corporate action of its Board of Directors and,
and shall have been duly filed with and accepted by the Secretary of State of
the State of Delaware.

     6.5 SECURITIES EXEMPTIONS. The offer and sale of the Shares to the
Purchaser pursuant to this Agreement shall be exempt from the registration
requirements of the Securities Act, and the registration and/or qualification
requirements of all applicable state securities laws.

     6.6 CLOSING OF ASSET PURCHASE AGREEMENT. The parties will have consummated
and closed the transactions contemplated by the Asset Purchase Agreement.

                                    SECTION 7

                  RESTRICTIONS ON TRANSFERABILITY OF SECURITIES

     7.1 RESTRICTIONS ON TRANSFERABILITY. The Securities shall not be
transferable except upon the conditions specified in this Section 7. The
Purchaser will cause any proposed transferee of the Securities held by the
Purchaser to agree to take and hold such Securities subject to the provisions
and upon the conditions specified in this Section 7.

     7.2 RESTRICTIVE LEGENDS. Each certificate representing the Securities, and
any other securities issued in respect of the Securities upon any stock split,
stock dividend, recapitalization, merger, consolidation or similar event (except
as otherwise permitted by the provisions of this Section 7), shall be stamped or
otherwise imprinted with legends in substantially the following form:


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          (a) THIS SECURITIES EVIDENCED BY THIS CERTIFICATE HAVE NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), OR
APPLICABLE STATE LAW, AND NO INTEREST THEREIN MAY BE SOLD, DISTRIBUTED,
ASSIGNED, OFFERED, PLEDGED OR OTHERWISE TRANSFERRED EXCEPT AS OTHERWISE SET
FORTH HEREIN AND UNLESS (A) THERE IS AN EFFECTIVE REGISTRATION STATEMENT UNDER
THE ACT AND APPLICABLE STATE SECURITIES LAWS COVERING ANY SUCH TRANSACTION, (B)
THE COMPANY RECEIVES AN OPINION OF LEGAL COUNSEL FOR THE HOLDER SATISFACTORY TO
THE COMPANY STATING THAT SUCH TRANSACTION IS EXEMPT FROM REGISTRATION OR (C) THE
COMPANY OTHERWISE SATISFIES ITSELF THAT SUCH TRANSACTION IS EXEMPT FROM
REGISTRATION.

          (b) Any other legends required by applicable state securities laws.

     The Company need not register a transfer of legended Securities and may
also instruct its transfer agent not to register the transfer of the Securities,
unless the conditions specified in each of the foregoing legends are satisfied.

     7.3 REMOVAL OF LEGEND AND TRANSFER RESTRICTIONS. Any legend endorsed on a
certificate pursuant to subsection 7.2(a) and the stop transfer instructions
with respect to such legended Securities shall be removed, and the Company shall
issue a certificate without such legend to the holder of such Securities, if
such Securities are registered under the Securities Act and a prospectus meeting
the requirements of Section 10 of the Securities Act is available or if such
holder satisfies the requirements of Rule 144(k).

                                    SECTION 8

                                  MISCELLANEOUS

     8.1 ENTIRE AGREEMENT; AMENDMENT. This Agreement and the exhibits to this
Agreement and the agreements reference herein constitute the full and entire
understanding and agreement between the parties with regard to the subjects
hereof and thereof, and any and all other written or oral agreements relating to
the subject matter hereof existing between the parties hereto are expressly
superseded hereby. Any term of this Agreement may be amended and the observance
of any term of this Agreement may be waived (either generally or in a particular
instance and either retroactively or prospectively) only with the written
consent of the party against whom enforcement of any such amendment or waiver is
sought. Any amendment or waiver effected in accordance with this Section 8.1
shall be binding upon the Company and the Purchaser and each future holder of
the securities purchased hereunder.

     8.2 GOVERNING LAW. This Agreement shall be governed in all respects by the
internal laws of the State of Delaware, without reference to principles of
choice of law.

     8.3 SURVIVAL. Unless otherwise set forth in this Agreement, the
representations, warranties covenants and agreements made herein shall survive
the execution and delivery of this Agreement and the Closing for a period of one
(1) year following the Closing.


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     8.4 SUCCESSORS AND ASSIGNS. Except as otherwise provided herein, the
provisions hereof shall inure to the benefit of, and be binding upon, the
successors, assigns, heirs, executors and administrators of the parties hereto.
Nothing in this Agreement, express or implied, is intended to confer upon any
party other than the parties hereto or their respective successors and assigns
any rights, remedies, obligations or liabilities under or by reason of this
Agreement, except as expressly provided in this Agreement.

     8.5 NOTICES, ETC. All notices and other communications required or
permitted hereunder shall be in writing and shall be deemed effectively given
(i) upon actual delivery to the party to be notified, (ii) 24 hours after
confirmed facsimile transmission, or (iii) one business day after deposit with a
recognized overnight courier, addressed (a) if to the Purchaser, at the
Purchaser's address set forth on the signature page hereto, or at such other
address as the Purchaser shall have furnished to the Company in writing upon 10
days' notice, (b) if to any other holder of any Securities, at such address as
such holder shall have furnished the Company in writing upon 10 days' notice or,
until any such holder so furnishes an address to the Company, to and at the
address of the last holder of such Securities who has so furnished an address to
the Company or (c) if to the Company, at the following address:

     ImaRx Therapeutics, Inc.
     1635 East 18th Street
     Tucson, AZ 85719
     Attention: Greg Cobb
     Fax: (___) __________

     With a copy to:

     John Steel
     DLA Piper Rudnick Gray Cary US LLP
     701 Fifth Avenue, Suite 7000
     Seattle, WA 98104
     Fax: (206) 839-4801

or at such other address as the Company shall have furnished to the Purchaser
upon 10 days' notice.

     8.6 COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which shall be enforceable against the parties actually
executing such counterparts, and all of which together shall constitute one
instrument.

     8.7 TITLES AND SUBTITLES; REFERENCES. The titles and subtitles used in this
Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement. All references in this Agreement to
sections, paragraphs, exhibits and schedules shall, unless otherwise provided,
refer to sections and paragraphs hereof and exhibits and schedules attached
hereto, all of which exhibits and schedules are incorporated herein by this
reference.


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     8.8 SEVERABILITY. If one or more provisions of this Agreement are held to
be unenforceable under applicable law, the parties agree to renegotiate such
provision in good faith. In the event that the parties cannot reach a mutually
agreeable and enforceable replacement for such provision, then such provision(s)
shall be excluded from this Agreement and the balance of the Agreement shall be
interpreted as if such provision(s) were so excluded and shall be enforceable in
accordance with its terms.

     8.9 EXPENSES. The Company and the Purchaser shall each bear their
respective expenses and legal fees incurred in connection with the negotiation
and consummation of this Agreement.

     8.10 DELAYS OR OMISSIONS. No delay or omission to exercise any right, power
or remedy accruing to any Purchaser, upon any breach or default of the Company
under this Agreement, shall impair any such right, power, or remedy, nor shall
it be construed to be a waiver of any such breach or default, or any
acquiescence therein, or of or in any similar breach or default thereafter
occurring; nor shall any waiver of any single breach or default be deemed a
waiver of any other breach or default theretofore or thereafter occurring. It is
further agreed that any waiver, permit, consent or approval of any kind of
character on a Purchaser's part of any breach or default under this Agreement,
or any waiver on a Purchaser's part of any provisions or conditions of this
Agreement must be in writing and shall be effective only to the extent
specifically set forth in such writing and that all remedies, either under this
Agreement, or by law or otherwise afforded to a Purchaser, shall be cumulative
and not alternative.

     8.11 ATTORNEY FEES. Notwithstanding any other provision herein, if any
action at law or in equity is necessary to enforce or interpret the terms of
this Agreement or the exhibits hereto, the prevailing party shall be entitled to
reasonable attorneys' fees, costs and disbursements in addition to any other
relief to which such party may be entitled.

                  [REST OF THIS PAGE INTENTIONALLY LEFT BLANK]


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     IN WITNESS WHEREOF, the parties hereto have executed this Series E
Preferred Stock Purchase Agreement as of September __, 2005.

                                        ABBOTT LABORATORIES


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


                                        IMARX THERAPEUTICS, INC.


                                        By: /s/ Evan Unger
                                            ------------------------------------
                                        Printed Name: Evan Unger
                                        Its: President and CEO