Exhibit 4.1

# SECURED CONVERTIBLE
NOTE PURCHASE AGREEMENT

THIS
AGREEMENT (this Agreement) is made as of November 20, 2003, by and among PFC
Therapeutics, LLC, a Delaware limited liability company (the Company), and
Technology Gateway Partnership, L.P., a California limited partnership (the
Purchaser).

WHEREAS,
the Company has agreed to sell to the Purchaser, and the Purchaser has agreed to purchase
from the Company, upon the terms and conditions hereafter provided, a Secured Convertible
Promissory Note in the form attached as Exhibit A hereto (the Note).

NOW
THEREFORE, in consideration of the mutual covenants and conditions set forth herein, the
sufficiency of which is hereby acknowledged, the parties hereby agree as follows:

1.    Issuance
of Note. Simultaneously with the execution of this           Agreement,
the Company is issuing to the Purchaser a Note in the aggregate           principal sum
of Five Hundred Thousand Dollars ($500,000) and the Purchaser is           paying to the
Company, by check or wire transfer, the amount of Five Hundred           Thousand Dollars
($500,000) in full payment of the Note.

2.    Representations
and Warranties of the Company. The Company hereby           represents and
warrants to the Purchaser as of the date hereof as follows:

(a)           Organization,
Good Standing and Qualification. The Company           is a limited
liability company duly organized, validly existing and in good           standing under
the laws of the State of Delaware and has all requisite limited           liability
company power and authority to carry on its business as now conducted           and to
own its properties. The Company is duly qualified to do business as a           foreign
corporation and is in good standing in each jurisdiction in which the           conduct
of its business or its ownership or leasing of property makes such
          qualification or leasing necessary unless the failure to so qualify has not and
          could not reasonably be expected to have a Material Adverse Effect (as defined
          below).

(b)           Authorization. The
Company has full power and authority and           has taken all requisite action on the
part of the Company, its officers,           managers and members necessary for (i) the
authorization, execution and delivery           of this Agreement, the Note and the
Security Agreement made by the Company in           favor of the Purchaser, dated as of
the date hereof (the Security           Agreement, and collectively with this
Agreement and the Note, the           Transaction Documents), (ii)
authorization of the performance of all           obligations of the Company hereunder
and thereunder, and (iii) the           authorization, issuance and delivery of the Note.
The Transaction Documents           constitute the legal, valid and binding obligations
of the Company, enforceable           against the Company in accordance with their terms,
subject to bankruptcy,           insolvency, fraudulent transfer, reorganization,
moratorium and similar laws of           general applicability, relating to or affecting
creditors rights           generally.

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(c)           Ownership
Interests. Alliance Pharmaceutical Corp., a New           York corporation
(Alliance) owns all of the issued and outstanding           units of
ownership interests (the Units) of the Company. All of the           Companys
issued and outstanding Units have been duly authorized and           validly issued and
are fully paid, nonassessable and free of pre-emptive rights           and were issued in
full compliance with applicable law. No person is entitled to           pre-emptive or
similar statutory or contractual rights with respect to any           securities of the
Company. There are no outstanding warrants, options,           convertible securities or
other rights, agreements or arrangements of any           character under which the
Company is or may be obligated to issue any Units.           There are no voting
agreements, buy-sell agreements, or right of first purchase           agreements among
the Company and any of the Companys members.           Notwithstanding the
foregoing, pursuant to (a) letter agreements dated June 18,           2003, Alliance has
agreed to convey (i) a 10% ownership interest in the Company           to Brown Simpson
Partners I, L.P.; (ii) an aggregate 2.14% ownership interest in           the Company to
Castle Creek Healthcare Investors, LLC, CC Life Sciences, Ltd.           and CCL Fund
LLC; and (iii) a 1.2% ownership interest in the Company to SDS           Merchant Fund,
L.P., and (b) an agreement dated October 28, 2003, Alliance has           agreed to
convey a 1.5% ownership interest in the Company to Stroock &          Stroock & Lavan
LLP.

(d)           Consents. The
execution, delivery and performance by the           Company of the Transaction
Documents, the granting of the security interests           pursuant to the Security
Agreement and the exercise of the rights granted to the           Purchaser therein
require no consent of, action by or in respect of, or filing           with, any person,
governmental body, agency, or official other than (i)           consents, actions or
filings that have been made prior to the date hereof which           are in full force
and effect, and (ii) post-sale filings pursuant to applicable           state and federal
securities laws which the Company undertakes to file within           the applicable time
periods. The granting of the security interest in the           Collateral pursuant to
the Security Agreement and the exercise of the rights           granted to the Purchaser
therein (including, without limitation, the disposition           of the Collateral) do
not require the consent, authorization or approval of any           governmental
authority.

(e)           No
Conflict, Breach, Violation or Default. The execution,           delivery
and performance of the Transaction Documents by the Company, the           issuance and
sale of the Note, the granting of the security interests pursuant           to the
Security Agreement and the exercise of the rights granted to the           Purchaser
therein do not and will not conflict with or result in a breach or           violation of
any of the terms and provisions of, or constitute a default under           (i) the
Companys Certificate of Formation or the Companys Limited           Liability
Company Operating Agreement, both as in effect on the date hereof, or           (ii)(a)
any statute, rule, regulation or order of any governmental agency or           body or
any court, domestic or foreign, having jurisdiction over the Company or           any of
its assets or properties, or (b) any agreement or instrument to which the
          Company is a party or by which the Company is bound or to which any of its
          assets or properties is subject.

(f)           Tax
Matters. The Company has timely prepared and filed all           tax
returns required to have been filed by the Company with all appropriate
          governmental agencies and timely paid all taxes shown thereon or otherwise owed
          by it. The charges, accruals and reserves on the books of the Company in
respect           of taxes for all fiscal periods are adequate in all material respects,
and there           are no material unpaid assessments against the Company nor, to the
          Companys knowledge after due inquiry, any basis for the assessment of any
          additional taxes, penalties or interest for any fiscal period or audits by any
          federal, state or local taxing authority except for any assessment which is not
          material to the Company. All taxes and other assessments and levies that the
          Company is required to withhold or to collect for payment have been duly
          withheld and collected and paid to the proper governmental entity or third
party           when due. There are no tax liens or claims pending or, to the Companys
          knowledge after due inquiry, threatened against the Company or any of its
assets           or property.

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(g)           Title
to Properties. The Company has good and marketable           title to all
real properties and all other properties and assets owned by it, in           each case
free from liens, encumbrances and defects that would materially affect           the
value thereof or materially interfere with the use made or currently planned           to
be made thereof by the Company; and the Company holds any leased real or
          personal property under valid and enforceable leases with no exceptions that
          would materially interfere with the use made or currently planned to be made
          thereof by them.

(h)           Certificates,
Authorities and Permits. The Company possess           adequate
certificates, authorities, licenses, approvals or permits issued by           appropriate
governmental agencies or bodies necessary to conduct the business           now operated
by it, and the Company has not received any notice of proceedings           relating to
the revocation or modification of any such certificate, authority or           permit
that, if determined adversely to the Company, could reasonably be           expected to
have a Material Adverse Effect, individually or in the aggregate.

(i)           No
Labor Disputes. No material labor dispute with the           employees of
the Company exists or, to the Companys knowledge after due           inquiry, is
imminent.

(j)           Intellectual
Property.

(1)                     All
Intellectual Property of the Company is currently in compliance with all           legal
requirements (including timely filings, proofs and payments of fees) and           is
valid and enforceable. Intellectual Property means all of the
          following: (i) patents, patent applications, patent disclosures and inventions
          (whether or not patentable and whether or not reduced to practice); (ii)
          trademarks, service marks, trade dress, trade names, corporate names, logos,
          slogans and Internet domain names, together with all goodwill associated with
          each of the foregoing; (iii) copyrights and copyrightable works; (iv)
          registrations, applications and renewals for any of the foregoing; (v) trade
          secrets, confidential information and know-how (including but not limited to
          ideas, formulae, compositions, manufacturing and production processes and
          techniques, research and development information, drawings, specifications,
          designs, business and marketing plans, and customer and supplier lists and
          related information); and (vi) proprietary computer software (including but not
          limited to data, data bases and documentation). No Intellectual Property of the
          Company which is necessary for the conduct of Companys business as
          currently conducted or as currently proposed to be conducted has been or is now
          involved in any cancellation, dispute or litigation, and, to the Companys
          knowledge after due inquiry, no such action is threatened. No patent of the
          Company has been or is now involved in any interference, reissue,
re-examination           or opposition proceeding.

(2)                     All
of the licenses and sublicenses and consent, royalty or other agreements
          concerning Intellectual Property which are necessary for the conduct of
          Companys business as currently conducted or as currently proposed to be
          conducted to which the Company is a party or by which any of its assets are
          bound (other than generally commercially available, non-custom, off-the-shelf
          software application programs having a retail acquisition price of less than
          $10,000 per license) (collectively, License Agreements) are valid
          and binding obligations of the Company and, to the Companys knowledge
          after due inquiry, the other parties thereto, enforceable in accordance with
          their terms, except to the extent that enforcement thereof may be limited by
          bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance or
          other similar laws affecting the enforcement of creditors rights
          generally, and, to the Companys knowledge after due inquiry, neither the
          Company nor any other party thereto is in material violation or breach of any
          such License Agreement, and no action or failure to act by the Company
          constitutes (with or without due notice or lapse of time or both) a material
          default by the Company thereunder.

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(3)                     The
Company has valid title and right to use all of the Intellectual Property           that
constitutes part of the Collateral (as defined in the Security Agreement).

(4)                     The
Company owns or has the valid right to use all of the Intellectual Property
          necessary for the conduct of the Companys business substantially as
          currently conducted or as currently proposed to be conducted and for the
          ownership, maintenance and operation of the Companys properties and
          assets.

(5)                     The
Company has taken reasonable steps to maintain, police and protect the
          Intellectual Property which it owns and which is necessary for the conduct of
          Companys business as currently conducted or as currently proposed to be
          conducted, including the execution of appropriate confidentiality agreements
and           intellectual property and work product assignments and releases. To the
          Companys knowledge after due inquiry, the conduct of the Companys
          business as currently conducted does not infringe or otherwise impair or
          conflict with (collectively, Infringe) any Intellectual Property
          rights of any third party, and, to the Companys knowledge after due
          inquiry, the Intellectual Property rights of the Company which are necessary
for           the conduct of Companys business as currently conducted or as
currently           proposed to be conducted are not being Infringed by any third party.
There is no           litigation or order pending or outstanding or, to the Companys
knowledge           after due inquiry, threatened or imminent, that seeks to limit or
challenge or           that concerns the ownership, use, validity or enforceability of
any Intellectual           Property of the Company or the Companys use of any
Intellectual Property           owned by a third party.

(6)                     The
consummation of the transactions contemplated hereby will not result in the
          alteration, loss, impairment of or restriction on the Companys ownership
          or right to use any of the Intellectual Property which is necessary for the
          conduct of Companys business as currently conducted or as currently
          proposed to be conducted.

(7)                     To
the Companys knowledge after due inquiry, except under confidentiality
          obligations, there has been no material disclosure of any of the Companys
          confidential information or trade secrets to any third party.

(k)           Environmental
Matters. The Company is not in violation of           any statute, rule,
regulation, decision or order of any governmental agency or           body or any court,
domestic or foreign, relating to the use, disposal or release           of hazardous or
toxic substances or relating to the protection or restoration of           the
environment or human exposure to hazardous or toxic substances           (collectively,
Environmental Laws), does not own or operate any real           property
contaminated with any substance that is subject to any Environmental           Laws, is
not liable for any off-site disposal or contamination pursuant to any
          Environmental Laws, and is not subject to any claim relating to any
          Environmental Laws, which violation, contamination, liability or claim has had
          or could reasonably be expected to have a Material Adverse Effect, individually
          or in the aggregate; and there is no pending or, to the Companys
          knowledge, threatened investigation that might lead to such a claim.

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(l)           Litigation. There
are no pending actions, suits or           proceedings against or affecting the Company
or any of its properties; and to           the Companys knowledge, no such actions,
suits or proceedings are           threatened or contemplated.

(m)           Insurance
Coverage. The Company maintains in full force and           effect
insurance coverage that is customary for comparably situated companies           for the
business being conducted and properties owned or leased by the Company.

(n)           Brokers
and Finders. No person will have, as a result of           the
transactions contemplated by this Agreement, any valid right, interest or           claim
against or upon the Company or the Purchaser for any commission, fee or           other
compensation pursuant to any agreement, arrangement or understanding           entered
into by or on behalf of the Company.

(o)           Disclosures. The
written materials delivered to the           Purchaser in connection with the
transactions contemplated by the Transaction           Documents do not contain any
untrue statement of a material fact or omit to           state a material fact necessary
in order to make the statements contained           therein, in light of the
circumstances under which they were made, not           misleading.

3.    Purchasers
Representations. In connection with the           Purchasers acquisition of
the Note, the Purchaser represents to the           Company the following:

(a)           Organization
and Existence. The Purchaser is a validly           existing limited
partnership under the laws of the State of California and has           all requisite
partnership power and authority to invest in the Note pursuant to           this
Agreement.

(b)           Authorization. The
execution, delivery and performance by           the Purchaser of the Transaction
Documents has been duly authorized and the           Transaction Documents will each
constitute the valid and legally binding           obligation of the Purchaser,
enforceable against the Purchaser in accordance           with their terms, subject to
bankruptcy, insolvency, fraudulent transfer,           reorganization, moratorium and
similar laws of general applicability, relating           to or affecting creditors rights
generally.

(c)           Purchase
Entirely for Own Account. The Note to be received           by the
Purchaser hereunder will be acquired for the Purchasers own           account, not
as nominee or agent, and not with a view to the resale or           distribution of any
part thereof in violation of the Securities Act of 1933, as           amended (the 1933
Act), and the Purchaser has no present intention           of selling, granting any
participation in, or otherwise distributing the same in           violation of the 1933
Act. The Purchaser is not a registered broker-dealer or           entity engaged in the
business of being a broker-dealer.

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(d)           Investment
Experience. The Purchaser acknowledges that it           can bear the
economic risk and complete loss of its investment in the Note and           has such
knowledge and experience in financial or business matters that it is           capable of
evaluating the merits and risks of the investment contemplated           hereby.
Purchaser acknowledges that there are substantial risks incident to the
          ownership of the Note, and such investment is speculative and involves a high
          degree of risk of loss by the Purchaser of the Purchasers entire
          investment in the Company.

(e)           Disclosure
of Information. The Purchaser has had an           opportunity to receive
all additional information related to the Company           requested and to ask
questions of and receive answers from the Company regarding           the Company, its
business and the terms and conditions of the sale of the Note.           Neither such
inquiries nor any other due diligence investigation conducted by           the Purchaser
shall modify, amend or affect the Purchasers right to rely           on the Companys
representations and warranties contained in this           Agreement.

(f)           Restricted
Securities. The Purchaser acknowledges and           understands that the
Note is a restricted security under the 1933           Act and must be held
indefinitely unless it is subsequently registered under the           1933 Act or an
exemption from such registration is available. The Purchaser           further
acknowledges and understands that the Company is under no obligation to
          register the Note. The Purchaser understands that the instrument evidencing the
          Note shall be imprinted with a legend which prohibits the transfer of the Note
          unless (i) it is registered, (ii) such registration is not required in the
          opinion of counsel satisfactory to the Company or (iii) it can be sold pursuant
          to Rule 144(k).

(g)           Accredited
Investor. The Purchaser is an accredited           investor as
defined in Rule 501(a) of Regulation D, as amended, under the           1933 Act.

(h)           No
General Solicitation. The Purchaser did not learn of the
          investment in the Note as a result of any public advertising or general
          solicitation.

(i)           Brokers
and Finders. No person will have, as a result of           the
transactions contemplated by this Agreement, any valid right, interest or           claim
against or upon the Company or the Purchaser for any commission, fee or           other
compensation pursuant to any agreement, arrangement or understanding           entered
into by or on behalf of the Purchaser.

(j)           Taxes. The
Purchaser understands that the Purchasers           investment in the Company may
result in tax consequences. The Purchaser shall           rely solely on the
determinations of their tax advisors or their own           determinations, and not on
any statements or representations by the Company or           any of its agents, with
regard to all such tax matters.

4.           Security
Agreement. As security for its performance of its           obligations under the
Note, the Company shall grant a first priority security           interest in certain
assets of the Company, as set forth in the Security           Agreement in the form
attached as Exhibit Bhereto.

5.           Alliance
Agreement. Pursuant to the Guarantee and Security           Agreement
attached hereto as Exhibit C (the Guaranty),           Alliance shall
irrevocably, absolutely and unconditionally guarantee to the           Purchaser the
performance of the Companys obligations under the Note.           Alliances
guarantee of the Companys obligations under the Note will           be secured by a
pledge and collateral assignment by Alliance of its right to           receive royalty
payments from sales of Imagent products (the           Earnout)
pursuant to that certain Asset Purchase Agreement, dated           June 18, 2003, by and
between Alliance and Photogen Technologies, Inc. (the            Asset Purchase
Agreement). In the event the Note is not, pursuant           to its terms,
converted in connection with a Financing (as defined below), the           Note shall be
terminated and Alliance and the Purchaser shall take all actions           necessary to
amend the Guaranty to (a) terminate the guarantee granted pursuant           to Section 2
of the Guaranty; and (b) provide that Alliance, pursuant to Section           3 of the
Guaranty, irrevocably, absolutely, and unconditionally collaterally           assigns to
the Secured Party 100% of the Earnout, up to an aggregate maximum           amount of
$1,500,000, to be paid to Oxygent Creditors (as defined in the Asset           Purchase
Agreement) after January 1, 2006 pursuant to Section 1.3 of the Asset           Purchase
Agreement.

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6.           Payment
Following Conversion of Note. In the event the           Purchaser elects
to convert the Note in connection with a Financing, the           Purchaser shall,
pursuant to the Guarantee and Security Agreement executed by           Alliance in favor
of Purchaser, also be entitled to receive 100% of the Earnout,           up to an
aggregate maximum amount of $500,000, to be paid to Oxygent Creditors           after
January 1, 2006 pursuant to Section 1.3 of the Asset Purchase Agreement.           For
purposes of this Agreement, the term Financing means a financing
          pursuant to which the Company receives gross proceeds of $10,000,000 (or such
          other amount approved by the Purchaser) from one or more investors, strategic
          partners, or other sources (or any combination of the foregoing). By way of
          example, the equity financing contemplated by the Term Sheet dated November 7,
          2003 by and among Alliance and SRS Capital-West, Inc. (as the same may be
          amended, modified, supplemented or restated from time to time) would be a
          Financing under this Agreement.

7.           Non-Occurrence
of Financing. In the event the Company does           not (a) obtain a
commitment for a Financing by January 15, 2004, and (b) close a           Financing by
January 31, 2004, then (i) the Company shall issue to the Purchaser           a warrant
substantially in the form of the warrant attached hereto as Exhibit           D (which
warrant shall entitle Purchaser to purchase, in exchange for           nominal
consideration, a number of Units equal to ten percent (10%) of the           Companys
issued and outstanding Units on a fully-diluted basis, and (ii)           the Company
shall amend its Limited Liability Company Operating Agreement to           provide that
the Purchaser shall have the right to designate a majority of the           members of
the Companys Board of Managers.

8.           Covenant
of Purchaser. The Purchaser hereby covenants and           agrees to vote
all shares of its shares of the Common Stock of Alliance (either           pursuant to a
proxy or otherwise) in favor of Proposal 2 described in           Alliances Notice
of the Annual Meeting of Stockholders to be held December           23, 2003 (the Notice),
and the proxy statement delivered in           connection with the Notice.

9.           General
Provisions.

(a)           Successors
and Assigns. Except as otherwise provided in           this Agreement,
this Agreement, and the rights and obligations of the parties           hereunder, will
be binding upon and inure to the benefit of their respective           successors,
assigns, heirs, executors, administrators and legal representatives.

(b)           Governing
Law. This Agreement will be governed by and           construed in
accordance with the laws of the State of California, without giving           effect to
that body of laws pertaining to conflicts of law.

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(c)           Counterparts.
This Agreement may be executed in any number           of counterparts, each of which
when so executed and delivered will be deemed an           original, and all of which
together shall constitute one and the same agreement.

(d)           Titles
and Headings. The titles, captions and headings of           this
Agreement are included for ease of reference only and will be disregarded           in
interpreting or construing this Agreement. Unless otherwise specifically
          stated, all references herein to sections and exhibits          will
mean sections and exhibits to this Agreement.

(e)           Notices.
Any and all notices required or permitted to be           given to a party pursuant to
the provisions of this Agreement will be in writing           and will be effective and
deemed to provide such party sufficient notice under           this Agreement on the
earliest of the following: (i) at the time of           personal delivery, if
delivery is in person; (ii) at the time of transmission by           facsimile, addressed
to the other party at its facsimile number specified herein           (or hereafter
modified by subsequent notice to the parties hereto), with           confirmation of
receipt made by both telephone and printed confirmation sheet           verifying
successful transmission of the facsimile; (iii) one (1) business day           after
deposit with an express overnight courier for United States deliveries, or           two
(2) business days after such deposit for deliveries outside of the United
          States, with proof of delivery from the courier requested; or (iv) three (3)
          business days after deposit in the United States mail by certified mail (return
          receipt requested) for United States deliveries. All notices for delivery
          outside the United States will be sent by facsimile or by express courier. All
          notices not delivered personally or by facsimile will be sent with postage
          and/or other charges prepaid and properly addressed to the party to be notified
          at the address or facsimile number as follows, or at such other address or
          facsimile number as such other party may designate by one of the indicated
means           of notice herein to the other parties hereto as follows:

(1)                     if
to the Purchaser, at 18881 VonKarman Ave., Suite 330, Irvine, CA 92612;
          Facsimile: (949) 752-0223.

(2)                     if
to the Company, marked Attention: President, at 6175 Lusk Blvd.,
          San Diego, CA 92121; Facsimile: (858) 410-5306.

(f)           Amendments
and Waivers. 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 Company and the Purchaser.           No delay or failure to
require performance of any provision of this Agreement           shall constitute a
waiver of that provision as to that or any other instance. No           waiver granted
under this Agreement as to any one provision herein shall           constitute a
subsequent waiver of such provision or of any other provision           herein, nor shall
it constitute the waiver of any performance other than the           actual performance
specifically waived.

(g)           Severability.
If any provision of this Agreement is           determined by any court or arbitrator of
competent jurisdiction to be invalid,           illegal or unenforceable in any respect,
such provision will be enforced to the           maximum extent possible given the intent
of the parties hereto. If such clause           or provision cannot be so enforced, such
provision shall be stricken from this           Agreement and the remainder of this
Agreement shall be enforced as if such           invalid, illegal or unenforceable clause
or provision had (to the extent not           enforceable) never been contained in this
Agreement. Notwithstanding the           foregoing, if the value of this Agreement based
upon the substantial benefit of           the bargain for any party is materially
impaired, which determination as made by           the presiding court or arbitrator of
competent jurisdiction shall be binding,           then both parties agree to substitute
such provision(s) through good faith           negotiations.

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(h)           Entire
Agreement. This Agreement, including Exhibits, and           the other
Transaction Documents, constitute the entire agreement and           understanding of the
parties with respect to the subject matter of this           Agreement, and supersede any
and all prior understandings and agreements,           whether oral or written, between
or among the parties hereto with respect to the           specific subject matter hereof.

(i)           Further
Assurances. The parties agree to execute such           further documents
and instruments and to take such further actions as may be           reasonably necessary
to carry out the purposes and intent of this Agreement.

(j)           Facsimile
Signatures. This Agreement may be executed and           delivered by
facsimile and upon such delivery the facsimile signature will be           deemed to have
the same effect as if the original signature had been delivered           to the other
party.

(k)           Costs
And Attorneys Fees. In the event that any           action, suit or
other proceeding is instituted concerning or arising out of this           Agreement or
any transaction contemplated hereunder, the prevailing party shall           recover all
of such partys costs and attorneys fees incurred in each           such
action, suit or other proceeding, including any and all appeals or           petitions
therefrom.

(l)           Costs,
Expenses. The Company and the Purchaser shall each           bear their
own expenses and legal fees incurred on behalf of each party with           respect to
this Agreement and the transactions contemplated hereby.

(m)           Waiver
of Conflict of Interest. Each Investor and the           Company is aware
that Foley & Lardner           (F&L) may have
previously performed and may           continue to perform certain legal services for the
Purchaser in matters           unrelated to F&Ls representation of the Company.
In connection with           its representation of Purchaser, F&L may have obtained
confidential           information of the Purchaser that could be material to F&Ls
          representation of the Company in connection with negotiation, execution and
          performance of this Agreement and the other Transaction Documents. By signing
          this Agreement, each of the Purchaser and the Company hereby acknowledges that
          the terms of this Agreement and the other Transaction Documents were negotiated
          between the Purchaser and the Company and are fair and reasonable and waives
any           potential conflict of interest arising out of such representation or such
          possession of confidential information. Each of the Purchaser and the Company
          further represents that it has had the opportunity to be, or has been,
          represented by independent counsel in giving the waivers contained in this
          Section 8(f).

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IN
WITNESS WHEREOF, the parties have duly executed this Agreement as of the day and year
first set forth above.

# COMPANY:

| | PFC Therapeutics, LLC 
| | ----------------------
| | /s/ Duane J. Roth     
| | Duane J. Roth, Manager

# PURCHASER:

| | Technology Gateway Partnership, L.P.                    
| | --------------------------------------------------------
| | /s/ Thomas O. Gephart                                   
| | Thomas O. Gephart, Managing Partner of Ventana          
| | Capital Partners, LLC, the General Partner of Technology
| | Gateway Partnership, L.P.                               

# ACKNOWLEDGED AND AGREED:

# Alliance Pharmaceutical
Corp.

/s/ Duane J. Roth Chairman and Chief
Executive Officer

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# EXHIBIT AFORM OF
NOTE

Exhibit A - Page 1

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# EXHIBIT BSECURITY AGREEMENT

Exhibit B - Page 1

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# EXHIBIT CGUARANTY AND
SECURITY AGREEMENT

Exhibit C - Page 1

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# EXHIBIT DFORM OF
WARRANT

Exhibit D - Page 1