<PAGE>


                                                                     Exhibit 4.1


                                OPTION AGREEMENT

         THIS OPTION AGREEMENT (this "AGREEMENT") dated as of this __ of June,
2001, is hereby entered into by and between [___________], a [__________]
[LIMITED PARTNERSHIP] (the "SELLER"), Alliance Pharmaceutical Corp., a New York
corporation ("ALLIANCE"), and Metracor Technologies, Inc. (formerly known as VIA
Medical Corporation), a California corporation ("METRACOR"), with reference to
the following:

         A.       Seller and Alliance are each "Investors" under that certain
                  Series B Preferred Stock Purchase Agreement (the "PURCHASE
                  AGREEMENT"), dated as of the date hereof, by and among
                  Metracor, Alliance, Seller and the other "Investors" named
                  therein, pursuant to which Seller and Alliance have agreed to
                  purchase shares of Metracor's Series B Preferred Stock (the
                  "METRACOR STOCK").

         B.       It is a condition precedent to the Purchase Agreement that
                  Seller and Alliance enter into this Agreement.

         NOW, THEREFORE, in consideration of the premises and the agreements
herein and in order to induce the parties to make their investment in, and other
valuable accommodations to, Metracor under the Purchase Agreement, the parties
hereto agree as follows:

         1.       DEFINED TERMS. In addition to any capitalized terms elsewhere
defined in this Agreement, the following capitalized terms shall have the
meanings given them below:

         "ACT" means the Securities Act of 1933, as amended from time to time.

         "ACQUISITION" means the consummation of a transaction whereby all or
substantially all of Metracor's property or business is sold or Metracor merges
into or consolidates with any other corporation in which more than fifty percent
(50%) of the voting power of Metracor is disposed of.

         "ALLIANCE OPTION TERM" means the period commencing with the date hereof
and ending on December 1, 2002 at 5:00 p.m. Pacific Time. .

         "ALLIANCE STOCK" means the common stock, par value $0.01 per share, of
Alliance.

         "IPO" means the sale of Metracor's common stock in a firm commitment
underwritten public offering pursuant to a registration statement on Form S-1
under the Act.

         "OPTION" means the Alliance Option and/or the Seller Option, described
below.

         "OPTION SHARES" means all of the shares of Metracor Stock held by
Seller, whether now or hereafter acquired and regardless of whether such shares
were acquired by purchase, stock dividend or split or any other means.

         "SELLER OPTION TERM" means the period commencing at 5:00 p.m. Pacific
Time on November 1, 2002 and ending at 5:00 p.m. Pacific Time on November 30,
2002, if and only if a Notice of Alliance Option Exercise has not been delivered
pursuant to SECTION 2(c) hereof prior


                                      -1-
<PAGE>


to 5:00 p.m. Pacific Time on November 1, 2002. Notwithstanding the foregoing, in
the event that (A) the closing sale price for one share of Alliance Stock as
reported on the Nasdaq National Market is above $8.00 for ten (10) consecutive
trading days or (B) Alliance consummates a single capital raising (i.e. not
including the issuance of securities to "strategic partners," that is, existing
or future licensees or assignees of technology rights from Alliance) equity
offering with net proceeds of $10,000,000 or more, then the Seller Option Term
shall commence on the date immediately after the date of such occurrence, if and
only if a Notice of Alliance Option Exercise has not then been delivered
pursuant to SECTION 2(c) hereof, and shall continue until November 30, 2002.

         2.       ALLIANCE OPTION.

                  (a)      OPTION GRANT. Seller hereby grants Alliance the
option (the "ALLIANCE OPTION") to purchase from Seller all (but not less than
all) of the Option Shares during the Alliance Option Term.

                  (b)      ALLIANCE OPTION EXERCISE PRICE. Alliance, in its sole
discretion, may effect the Alliance Option by either (i) payment to Seller of
$0.93273 per Option Share in immediately available cash funds (the "CASH PRICE")
or (ii) issuance to Seller of 0.13072 shares of Alliance Stock per Option Share
(such ratio determined as of the date hereof with reference to the current
capitalization of Alliance and to be adjusted accordingly to reflect fully the
effect of any stock split, reverse stock split, stock dividend, reorganization,
recapitalization or similar change with respect to Alliance Stock after the date
hereof, the "SHARE RATIO").

                  (c)      NOTICE OF ALLIANCE OPTION EXERCISE. The Alliance
Option shall be exercisable during the Alliance Option Term by delivery to
Seller (at the address set forth in SECTION 8 below) of a duly executed "NOTICE
OF ALLIANCE OPTION EXERCISE" substantially in the form attached hereto as
EXHIBIT A, which Notice of Alliance Option Exercise shall include the total
number of Option Shares to be purchased and the total Cash Price or the total
number of shares of Alliance Stock to be issued (as determined by the Share
Ratio) in consideration for such shares of Metracor Stock. The transfer of the
Option Shares from Seller to Alliance pursuant to the exercise of the Alliance
Option shall be made in compliance with SECTION 4 below.

         3.       SELLER OPTION.

                  (a)      OPTION GRANT. During the Seller Option Term, upon
election of the holders of a majority of the then issued and outstanding shares
of Metracor Stock (determined without taking into account any shares of Metracor
Stock then held by Alliance, the "MAJORITY HOLDERS"), Seller shall sell to
Alliance and Alliance shall purchase from Seller all of the Option Shares (the
"SELLER OPTION").

                  (b)      SELLER OPTION EXERCISE PRICE. The exercise price for
the Seller Option shall be the Cash Price per Option Share; PROVIDED, however,
that Alliance shall have the right, in its sole discretion, within thirty (30)
days of receipt of a Notice of Seller Option Exercise delivered in accordance
with SECTION 3(c) below, to elect to purchase the Option Shares by


                                      -2-
<PAGE>


issuing that number of shares of Alliance Stock determined with reference to the
then current Share Ratio multiplied by the number of Option Shares.

                  (c)      EXERCISE MECHANICS. The Seller Option shall be
exercisable during the Seller Option Term by delivery by the Majority Holders to
Alliance (at the address set forth in SECTION 8 below) of a duly executed
"NOTICE OF SELLER OPTION EXERCISE" substantially in the form attached hereto as
EXHIBIT B. The transfer of the Option Shares from Seller to Alliance shall be
made in compliance with SECTION 4 below.

         4.       OPTION SHARE TRANSFER.

                  (a)      The transfer of the Option Shares pursuant to the
exercise of an Option hereunder (the "TRANSFER") shall occur forty-five (45)
days after the date that the applicable Notice of Alliance Option Exercise or
Notice of Seller Option Exercise is delivered unless such transfer is sooner
consummated by the parties hereto by mutual consent or by reason of the purchase
of the Option Shares under SECTION 3(B) with shares of Alliance Stock.

                  (b)      A closing shall be held at a mutually convenient time
and place on the date the Transfer is to occur (or the immediately succeeding
business day) and the parties shall execute and deliver the following documents
and instruments:

                           (i)      a Stock Transfer Agreement, dated as of the
date of such Transfer, substantially in the form of EXHIBIT C hereto, shall be
executed by each of Alliance and the Seller;

                           (ii)     the Seller shall deliver to Alliance the
certificates evidencing the Option Shares duly endorsed for transfer to Alliance
accompanied by signed written instructions to Metracor to transfer the Option
Shares to Alliance as record holder on the books and records of Metracor; and

                           (iii)    Alliance shall deliver by wire transfer to
an account furnished to Alliance by Seller the aggregate Cash Price to be paid
in consideration for the Option Shares, unless Alliance has determined to effect
the Transfer by issuing shares of Alliance Stock utilizing the then current
Share Ratio, in which case Alliance shall deliver certificates evidencing such
shares.

                  (c)      The Transfer shall be deemed to have been consummated
immediately prior to the close of business on the date provided above in SECTION
4(a) above. Accordingly, Alliance shall be treated for all purposes as the
holder of record of Option Shares as of the close of business on such date and
Seller shall be treated for all purposes as the holder of the number of shares
of Alliance Stock being issued thereto, if any, in consideration for the Option
Shares. Except for rights enjoyed by Alliance in any voting, shareholders'
rights or other related agreement executed by the Seller (among others),
Alliance shall not be entitled to vote or receive dividends or be deemed the
holder of the Option Shares for any purpose until the Transfer has been
consummated.

         5.       ISSUANCE OF ALLIANCE STOCK.


                                      -3-
<PAGE>


                  (a)      RESTRICTED SECURITIES. The issuance of shares of
Alliance Stock, if any, pursuant to the exercise of an Option hereunder (the
"ALLIANCE SHARES"), will not be registered under the Act, in reliance on
exemptions from the registration requirement of Section 5 of the Act set forth
in Section 4(2) thereof or Regulation D promulgated thereunder.

                  (b)      SELLER REPRESENTATIONS. The Holder hereby makes the
representations, warranties and covenants set forth on EXHIBIT D hereto as
though fully set forth herein.

                  (c)      ALLIANCE REPRESENTATIONS. Alliance represents and
warrants to Seller, as of the date of this Agreement, as follows:

                           (i)      ORGANIZATION. Alliance is a corporation (a)
organized, validly existing and in good standing under the laws of the State of
New York; and (b) duly qualified and in good standing to do business in every
jurisdiction where the nature of its business or the location of its properties
requires such qualification and in which the failure to do so would have a
material adverse effect on its business. Alliance has all requisite power
authority to own, lease and operate its properties and to carry on its business
as now being conducted, and possesses all licenses, franchises, rights and
privileges material to the conduct of business.

                           (ii)     AUTHORITY. Alliance has all requisite
corporate power authority to enter into this Agreement, and, subject to
satisfaction of the conditions set forth herein, to consummate the transactions
hereby. The execution and delivery of this and the consummation of the
transactions contemplated hereby have been duly authorized by all necessary
corporate action on the part of Alliance . This Agreement has been duly executed
and delivered by Alliance and constitutes a valid and binding obligation
Alliance, enforceable against it in accordance with its terms, subject to the
effect of applicable bankruptcy, insolvency, reorganization, moratorium or other
similar federal or state laws affecting the rights of creditors and the effect
or availability of rules of law governing specific performance, injunctive
relief or ether equitable remedies (regardless of whether any such remedy is
considered in a proceeding at law or in equity). Assuming the accuracy of
Holder's representations in EXHIBIT D, the execution and the delivery of this
Agreement does not, and the consummation of the transactions contemplated hereby
will not, conflict with, or result in any violation of or default (with or
without notice or lapse of time, or both) under, or give rise to a right of
termination, cancellation or acceleration of any obligation or to loss of a
material benefit, or result in the creation of any lien, encumbrance or
restriction in favor of any third party upon any of assets or properties of
Alliance, under (a) any provision of the Certificate of Incorporation or Bylaws
of Alliance or (b) any agreement or instrument, permit, license, judgment,
order, statute, law, ordinance, rule or regulation applicable to Alliance or its
properties or assets, other than any such conflicts, violations, defaults,
terminations, cancellations accelerations which individually or in the aggregate
would not have a material adverse effect on Alliance taken as a whole.

                           (iii)    ALLIANCE CAPITAL STRUCTURE. The authorized
capital stock of Alliance consists of 125,000,000 shares of Common Stock
("Common Stock"), $0.01 par value per share, and 5,000,000 shares of Preferred
Stock, $0.01 par value per share ("Preferred Stock"), consisting of 875,000
shares of authorized Series F Preferred Stock ("Series F Preferred Stock"),
13,637 shares of authorized Series G Preferred Stock ("Series G Preferred
Stock"), 13,636 shares of authorized Series H Preferred Stock ("Series H
Preferred Stock"), and


                                      -4-
<PAGE>


4,097,727 shares of unauthorized undesignated Preferred Stock. At the close of
business on June 18, 2001 (a) 49,541,071 shares of Alliance Common Stock were
issued and outstanding; (b) 600,000 shares of Series F Preferred Stock were
issued and outstanding, (c) no shares of Series G Preferred Stock or Series H
Preferred Stock were issued and outstanding; (d) 11,638,625 shares of Common
Stock were reserved for issuance upon exercise of options under its stock plans,
of which 8,711,818 options to purchase shares were outstanding and (e) 1,193,142
shares of Common Stock were reserved for issuance for outstanding warrants, of
which warrants to purchase 1,193,142 shares of Common Stock were issued and
outstanding. Alliance has debt outstanding in the amount of $27,900,000
convertible into equity of Alliance. Except as set forth above and in the
disclosure schedule attached hereto as SCHEDULE 1, there are no equity
securities of any class of Alliance, or any security or obligation exchangeable
into or for any equity securities of Alliance issued or outstanding or reserved
for issuance. Except as set forth (a) above, (b) in the disclosure schedule
attached hereto as SCHEDULE 1, and (c) in this Agreement, there are no other
options (other than under the Alliance stock option plans referred to above),
warrants, calls, rights, commitments, or agreements of any character to which
upon is a party or by which it is bound obligating Alliance to issue, deliver or
sell, or cause to issued, delivered or sold, additional shares of Alliance
capital stock or obligating Alliance to grant, extend or enter into any such
option, warrant, call, right, commitment, or agreement.

                           (iv)     ALLIANCE SHARES. The Alliance Shares will,
when issued and if delivered to the Seller in accordance with this Agreement, be
duly authorized, validly issued, fully paid and nonassessable, and issued in
compliance with applicable federal and state securities laws.

                           (v)      FINANCIAL STATEMENTS. Alliance has made
available to Seller a complete and accurate copy of each report, schedule (other
than registration statements), and definitive proxy statement filed by Alliance
with the SEC on or after June 30, 1998 (the "SEC REPORTS"), which are all such
reports and documents (other than registration statements) required to be filed
by Alliance with the SEC since June 30, 1998. Each of the sets of financial
statements (including, in each case, any notes thereto) contained in the SEC
Reports (i) complied as to form in all material respects with the published
rules and regulations of the SEC applicable thereto; (ii) was prepared in
accordance with GAAP applied on a consistent basis throughout the periods
involved (except as may be indicated in the notes thereto); and (iii) fairly
presents the financial position of Alliance at the respective dates thereof and
the results of operations and cash flows for the periods indicated.

                           (vi)     LITIGATION. Except as may be disclosed in
the SEC Reports, there are no legal proceedings to which Alliance is a party or
of which its property is subject which are material in relation to Alliance's
financial statements.

                           (vii)    ABSENCE OF CHANGES. Except as disclosed in
the SEC Reports, between June 30, 2000 (the date of Alliance's last audited
financial statement) and the date of this Agreement, there has not been any
event that has had or will have a material adverse effect on the business,
assets, properties, operations, or condition (financial or otherwise) of
Alliance.

                           (viii)   DISCLOSURE. None of the SEC Reports contain
any untrue statement of a material fact or omit to state any material fact
required to be stated therein or necessary in


                                      -5-
<PAGE>


order to make the statements therein, in light of the circumstances under which
they were made, not misleading.

                  (d)      COMPLIANCE WITH SECURITIES LAWS.

                           (i)      Seller, by acceptance hereof, acknowledges
that this Agreement and the Alliance Shares which may be issued upon exercise of
an Option hereunder are being acquired solely for the Seller's own account and
not as a nominee for any other party, and for investment, and that the Seller
will not offer, sell or otherwise dispose of any of Alliance Shares except under
circumstances that will not result in a violation of any applicable federal and
state securities laws (including, without limitation, the Act). Upon exercise of
an Option hereunder, Seller shall, if requested by Alliance, confirm in writing,
in a form satisfactory to Alliance, that the representations set forth on
EXHIBIT D hereto are true as of the date of the Transfer and that the Alliance
Shares to be issued, if any, are being acquired solely for the Seller's own
account and not as a nominee for any other party, for investment, and not with a
view toward distribution or resale.

                           (ii)     Alliance Shares which may be issued upon
exercise of an Option hereunder shall be stamped or imprinted with a legend in
substantially the following form (in addition to any legend required by
applicable state securities laws):

       "THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED OR QUALIFIED
        UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS OF
        ANY STATE, AND MAY BE OFFERED AND SOLD ONLY IF REGISTERED AND QUALIFIED
        PURSUANT TO THE RELEVANT PROVISIONS OF FEDERAL AND STATE SECURITIES LAWS
        OR IF REGISTRATION AND QUALIFICATION UNDER FEDERAL AND STATE SECURITIES
        LAWS ARE NOT REQUIRED."


                  (e)      NO FRACTIONAL SHARES OR SCRIP. No fractional shares
or scrip representing fractional shares of Alliance Stock shall be issued upon
the exercise of an Option hereunder. In lieu of any fractional share to which
the Seller would otherwise be entitled, Alliance shall make a cash payment equal
to the closing sale price for one share of Alliance Stock as reported on the
Nasdaq National Market on the trading day immediately preceding the date of the
Transfer multiplied by such fraction.

                  (f)      REGISTRATION RIGHTS. Alliance shall use its best
efforts to cause, promptly after and in any event within 90 days of the issuance
of Alliance Shares, if any, a registration statement on Form S-3 (or any
equivalent successor form) to be filed with the Securities and Exchange
Commission in order to register such Alliance Shares, and Alliance shall bear
and pay all reasonable related costs incurred in connection with such
registration (excluding underwriting discounts and commissions, if any).

         6.       CERTAIN CASH PRICE AND SHARE RATIO ADJUSTMENTS. The Cash Price
and the Share Ratio are subject to adjustment from time to time as follows:


                                      -6-
<PAGE>


                  (a)      RECLASSIFICATION, CONVERSION, ETC. If, at any time
while any Option remains outstanding and unexpired, Metracor or Alliance shall
by reclassification of securities or otherwise, change any of the securities as
to which purchase rights under such Option exist into the same or a different
number of securities of any other class or classes, or the Option Shares shall
convert, by the terms of the Metracor's or Alliance's Articles of Incorporation,
into the same or a different number of securities of any other class or classes,
in any such event such Option shall thereafter represent the right to acquire
such number and kind of securities as would have been issuable as the result of
such change with respect to the securities that were subject to the purchase
rights under such Option immediately prior to such reclassification, conversion
or other change and the Cash Price and Share Ratio therefor shall be
appropriately adjusted, all subject to further adjustment as provided in this
SECTION 6.

                  (b)      SPLIT, SUBDIVISION OR COMBINATION OF SHARES. If
Metracor or Alliance, at any time while any Option hereunder remains outstanding
and unexpired, shall split, subdivide or combine the securities as to which
purchase rights under such Option exist into a different number of securities of
the same class, the Cash Price and Share Ratio for such securities and the
number of securities into which such Option is convertible shall be
proportionately adjusted, all subject to further adjustment as provided in this
SECTION 6.

                  (c)      NO IMPAIRMENT. Seller will not, by any voluntary
action, avoid or seek to avoid the observance or performance of any of the terms
to be observed or performed hereunder by Seller, but will at all times in good
faith assist in the carrying out of all the provisions of this SECTION 6 and in
the taking of all such action as may be necessary or appropriate in order to
protect the rights of Alliance against impairment.

         7.       TRANSFER OR CONVERSION OF OPTION SHARES. Seller hereby agrees
that during such time as its Option Shares are subject to the Alliance Option,
Seller shall not, without the prior written consent of a duly authorized
representative of Alliance, (i) sell, transfer, assign, convey, gift, pledge,
hypothecate or dispose of in any way (collectively, "TRANSFER") or (ii) convert
into Common Stock or any other security of the Company (a "CONVERSION"), the
Option Shares held by Seller. In the event that Alliance does consent in writing
to a Transfer of all or part of the Option Shares, it shall be a condition
precedent to such Transfer that such transferee agree to in writing to be bound
by the obligations of this Agreement and the Alliance Option. In the event that
Alliance does consent in writing to a Conversion of all or part of the Option
Shares, Seller hereby agrees that the shares resulting from such Conversion
shall be considered Option Shares subject to the Alliance Option for all
purposes under this Agreement.

         8.       LEGENDS. During the Alliance Option Term, each certificate
representing such Option Shares shall be endorsed with substantially the
following legend:

                  THE SHARES EVIDENCED HEREBY ARE SUBJECT TO TRANSFER
                  RESTRICTIONS REGARDING THEIR SALE, TRANSFER, ASSIGNMENT,
                  CONVEYENCE, GIFT, PLEDGED, HYPOTHECATION OR DISPOSAL
                  ("TRANSFER"), AS DESCRIBED IN A CERTAIN OPTION AGREEMENT
                  EXECUTED BY THE HOLDER HEREOF (A COPY OF WHICH MAY BE OBTAINED
                  FROM THE ISSUER). NO TRANSFER SHALL BE PERMITTED, AND ANY
                  ATTEMPTED TRANSFER SHALL BE INVALID,


                                      -7-
<PAGE>


                  UNLESS SUCH TRANSFER RESTRICTIONS ARE FULLY COMPLIED WITH
                  PRIOR TO THE TRANSFER OF SUCH SHARES.

         9.       TERMINATION OF ALLIANCE OPTION AND SELLER OPTION.

                  (a)      EARLY TERMINATION OF ALLIANCE OPTION AND SELLER
OPTION UPON IPO OR ACQUISITION. Notwithstanding any provision to the contrary in
this Agreement, each of the Alliance Option and Seller Option shall expire upon
either (i) the date immediately preceding the date of the closing of an IPO, or
(ii) the date immediately preceding the closing date of an Acquisition.

                  (b)      EARLY TERMINATION OF SELLER OPTION BY ALLIANCE. The
parties hereto hereby acknowledge that Alliance has entered into this Agreement
based upon the representations and warranties of Metracor as set forth in
Section 2 of the Purchase Agreement, including the representations and
warranties set forth in Section 2.2 of the Purchase Agreement (the
"CAPITALIZATION REPRESENTATION"). In the event that Metracor has not taken the
actions specified in SECTION 9(c) herein prior to the commencement of the Seller
Option Term, then Alliance, in its sole discretion, may elect to terminate the
Seller Option by giving written notice of such election to Metracor and the
Seller pursuant to SECTION 11 hereto.

                  (c)      REQUIREMENT TO VERIFY METRACOR CAPITALIZATION AND
CURE. Metracor agrees to promptly (and in all events, prior to the commencement
of the Seller Option Term) take all necessary action to confirm and verify the
Capitalization Representation and cause to be delivered to Alliance a
supplemental legal opinion regarding the Capitalization Representation both in a
form and with such customary assumptions and qualifications, and such
non-material exceptions , all as reasonably acceptable to Alliance. Furthermore,
Metracor hereby agrees to promptly notify Alliance in reasonable detail in
writing, pursuant to SECTION 11 hereto, in the event that Metracor is made aware
or discovers any breach in the Capitalization Representation. In the event that
there is a material breach in the Capitalization Representation ("MATERIAL
BREACH"), Metracor shall promptly take all steps reasonably acceptable to both
Alliance and Metracor to provide Alliance with the same economic benefit (which
may include but is not limited to the same equity interest in the Metracor
capital stock with the same rights, privileges and preferences as described in
the Amended and Restated Articles of Incorporation of Metracor) deriving from
the transactions resulting from the Purchase Agreement and this Agreement, had
the Capitalization Representation been true and correct as of the date of the
Purchase Agreement.

                  (d)      "MATERIAL BREACH". For purposes of clarification but
not limitation in SECTION 9(c) hereto, a "Material Breach" shall be deemed to
exist if the number of shares of issued and outstanding capital stock of
Metracor (on a fully diluted basis, assuming the conversion or exercise of all
issued and outstanding options, warrants and other securities convertible into
equity of Metracor, and assuming conversion of all preferred stock into common
stock) (the "METRACOR CAPITALIZATION"), as set forth in the Capitalization
Representation (the "REPRESENTED METRACOR CAPITALIZATION"), "materially
deviates" (as defined below) from the actual Metracor Capitalization as of the
date of the Purchase Agreement (the "ACTUAL METRACOR CAPITALIZATION"). For
purposes of the foregoing sentence, the Represented Metracor Capitalization
shall be deemed to "MATERIALLY DEVIATE" from the Actual Metracor Capitalization
if


                                      -8-
<PAGE>


the positive difference of the Actual Metracor Capitalization less the
Represented Metracor Capitalization is two and one-half percent (2 1/2 %) or
more of the Represented Metracor Capitalization.

         10.      SUCCESSORS AND ASSIGNS. Any assignment of this Agreement or
the Options provided for herein by a party hereto, without the written consent
of the other party, shall be null and void. The terms and conditions of this
Agreement shall inure to the benefit of and be binding upon the respective
successors and permitted assigns of the parties.

         11.      NOTICES. All notices, advices and communications shall be
deemed to have been received (i) in the case of personal delivery, on the date
of such delivery, (ii) in the case of mailing by first class mail, on the fifth
(5th) business day following the date of such mailing, and (iii) in the case of
delivery by overnight courier, on the first (1st) business day following the
date of mailing. The respective notice addresses for the parties hereto shall be
the address set forth on the signature page hereto or such other address as may
be given in writing by a party hereto to the other party.

         12.      AMENDMENTS; WAIVERS. Any term of this Agreement may be amended
in a executed by the parties hereto. No waivers of, or exceptions to, any term,
condition or provision of this Agreement, in any one or more instances, shall be
deemed to be, or construed as, a further or continuing waiver of any such term,
condition or provision and shall not be valid unless in writing.

         13.      GOVERNING LAW; ATTORNEYS' FEES. This Agreement shall be
governed by and construed in accordance with the laws of the State of California
without giving effect to the principles of conflicts of law. In the event of any
litigation in relation to this Agreement or any Option Shares or Alliance Shares
issued or to be issued hereunder, the prevailing party shall be paid by the
other party a reasonable sum for attorneys' fees and expenses of such prevailing
party.


                                      -9-
<PAGE>


         IN WITNESS WHEREOF, the undersigned has caused this Agreement to be
executed by its officers thereunto duly authorized as of the date first above
written.



                                         ALLIANCE PHARMACEUTICAL CORP.
                                         a New York corporation


                                         By:
                                            ------------------------------------
                                             Theodore D. Roth, President

                                         3040 Science Park Road
                                         San Diego, CA  92121
                                         Attn:   Lloyd Rowland
                                         Fax:    (858) 410-5343


                                         METRACOR TECHNOLOGIES, INC.
                                         a California corporation


                                         By:
                                            ------------------------------------
                                             Randall L. Whitfield, President

                                         11425 Sorrento Valley Road
                                         San Diego, CA  92121
                                         Attn:  President


<PAGE>


         IN WITNESS WHEREOF, the undersigned has caused this Agreement to be
executed by its officers thereunto duly authorized as of the date first above
written.



                                         [SELLER]
                                         a limited partnership


                                         By:
                                            ------------------------------------
                                         Its:
                                             -----------------------------------

                                         [Address]

                                         ---------------------------------------
                                         Attn:
                                                 -------------------------------
                                         Fax:
                                                 -------------------------------


<PAGE>


         IN WITNESS WHEREOF, the undersigned has caused this Agreement to be
executed by its officers thereunto duly authorized as of the date first above
written.

                                         GALEN PARTNERS III, L.P.

                                         By:  Claudius, L.L.C., its
                                              General Partner

                                         By:
                                              ----------------------------------

                                         Its:
                                              ----------------------------------

                                         Address: Galen Partners III, L.P.
                                                  c/o Galen Associates
                                                  610 Fifth Avenue
                                                  New York, New York 10020


                                         GALEN PARTNERS INTERNATIONAL III, L.P.

                                         By:      Claudius, L.L.C., its
                                                  General Partner

                                         By:
                                                  ------------------------------
                                         Its:
                                                  ------------------------------


                                         Address: Galen Partners International
                                                  III, L.P.
                                                  c/o Galen Associates
                                                  610 Fifth Avenue
                                                  New York, New York 10020


                                         GALEN EMPLOYEE FUND III, L.P.

                                         By:      Wesson Enterprises, Inc., its
                                                  General Partner

                                         By:
                                                  ------------------------------

                                         Its:
                                                  ------------------------------

                                         Address: Galen Partners International
                                                  III, L.P.
                                                  c/o Galen Associates
                                                  610 Fifth Avenue
                                                  New York, New York 10020


<PAGE>


                                    EXHIBIT A

                       NOTICE OF ALLIANCE OPTION EXERCISE

To:      [SELLER]

Date:
         ---------------

         Alliance Pharmaceutical Corp. ("ALLIANCE") hereby gives notice of its
intent to effect the Alliance Option as defined in and pursuant to the terms of
that certain Option Agreement dated as of June __, 2001 by and between Alliance
and you, the "SELLER" (the "OPTION AGREEMENT"). All capitalized terms used
herein without definition shall have the meanings ascribed such terms in the
Option Agreement.


         Alliance hereby elects to effect the Alliance Option on ______ Option
Shares held by Seller and, in consideration therefor, shall:

                  / /      pay $_________ representing the aggregate cash price
                           for the Option Shares; or

                  / /      issue _________ shares of Alliance Stock representing
                           the Share Ratio multiplied by the number of Option
                           Shares.




                                         ALLIANCE PHARMACEUTICAL CORP.,
                                         a New York corporation


                                         By:
                                                --------------------------------
                                         Its:
                                                --------------------------------


<PAGE>


                                    EXHIBIT B

                        NOTICE OF SELLER OPTION EXERCISE


To:      Alliance Pharmaceutical Corp.

Date:
         ----------------

         The undersigned, being the Majority Holders defined in and pursuant to
those certain Option Agreements, dated as of June ___, 2001, by Alliance, on the
one hand, and each of the undersigned, on the other hand (the "OPTION
AGREEMENT"). All capitalized terms used herein without definition shall have the
meanings ascribed such terms in the Option Agreement.

         The undersigned hereby give notice of their intent to effect the Seller
Option under the Option Agreement for the Option Shares set forth on the
attached schedule and held by each of the undersigned.

                                         [SELLER]


                                         By:
                                                --------------------------------
                                         Its:
                                                --------------------------------



                                         [SELLER]


                                         By:
                                                --------------------------------
                                         Its:
                                                --------------------------------


                                      B-1
<PAGE>


                                    EXHIBIT C

                            STOCK TRANSFER AGREEMENT


         This Stock Transfer Agreement (this "AGREEMENT"), dated effective as of
______ __, 200_, is entered into by and among [__________], L.P., a [_________]
limited partnership (the "SELLER") and Alliance Pharmaceutical Corp., a New York
corporation ( "ALLIANCE") with respect to those certain shares of Series B
Preferred Stock of METRACOR Medical Corporation, a California corporation
("METRACOR") currently owned by the Seller with reference to the following:

         A.       Seller owns __________ (____) shares of the Metracor's Series
                  B Preferred Stock (the "SHARES").

         B.       Seller and Alliance have entered into that certain Option
                  Agreement (the "OPTION AGREEMENT") dated as of June __, 2001,
                  pursuant to which Alliance, under certain circumstances, is
                  entitled to purchase the Shares from Seller and Seller, under
                  certain circumstances, is entitled to sell the Shares to
                  Alliance. All capitalized terms used herein without definition
                  shall have the meanings ascribed such terms in the Option
                  Agreement.

         C.       An Option is being exercised under and as defined in the
                  Option Agreement.

         D.       Under the terms of the Option Agreement, the transfer of the
                  Shares pursuant to an exercise of an Option is to be effected
                  through the use of this Agreement, such that Alliance will
                  receive its interest in the Shares on the terms, and subject
                  to the conditions, set forth in this Agreement.

         Now, therefore, the parties hereby agree as follows:

                  (a)      TRANSFER OF SHARES. Subject to due receipt of the
consideration set forth below, as of the date hereof, Seller hereby transfers
the Shares to Alliance, as well as all rights, privileges and restrictions
associated with the Shares. Seller hereby agrees to take any and all steps
necessary to effect such transfer. In connection therewith, Alliance shall
receive the "CERTIFICATES" representing the Shares duly endorsed for the
transfer being made hereunder (the "TRANSFER"), together with signed
instructions from the Seller to Metracor regarding the Transfer.

                  (b)      CONSIDERATION. In consideration for the Transfer,
Alliance shall deliver concurrent [_____ number of shares of Alliance
Stock][$_______ by wire transfer in immediately available funds to the account
of the Seller as designated thereby].

                  (c)      REPRESENTATIONS AND WARRANTIES. Seller hereby
represents and warrants to the Company that the investor representations
attached as EXHIBIT D to the Option Agreement are true and correct as of the
date hereof and at the time of the Transfer.


                                      C-1
<PAGE>


                  (d)      MISCELLANEOUS.

                           (i)      This Agreement shall be governed by and
construed in accordance with the internal laws of the State of California
(without regard to the conflicts of law principles thereof).

                           (ii)     This Agreement, the Option Agreement
together with the attachments thereto and the deliveries made in respect
thereof, embody the entire understanding between the parties and supersedes any
prior understandings, agreements and arrangements between the parties respecting
the subject matter hereof. There are no representations, warranties, agreements,
arrangements or understandings, oral or written, between the parties hereto
relating to the subject matter of this Agreement which are not fully expressed
herein.

                           (iii)    This Agreement may be executed in
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument. The execution and
delivery of signatures for this Agreement may occur via telecopy, and such
telecopied signature pages shall have the force and effect of original signature
pages.

                           (iv)     Any notice, request or other communications
required or permitted hereunder shall be given upon personal delivery or upon
the SEVENTH (7TH) day following mailing by registered airmail (or certified
first class mail if both the addresser and addressee are located in the United
States), postage prepaid and addressed to the parties set forth in the Option
Agreement.

                           (v)      Each party to this Agreement agrees to
perform any further acts and to execute and deliver any other documents that may
be reasonably necessary to carry out the provisions of this Agreement.

         In Witness Whereof, the parties have executed this Agreement.


                                         [SELLER]


                                         By:
                                              ----------------------------------
                                         Its:
                                              ----------------------------------


                                         ALLIANCE PHARMACEUTICAL CORP.


                                         By:
                                              ----------------------------------
                                         Its:
                                              ----------------------------------


                                      C-2
<PAGE>


                                    EXHIBIT D

               HOLDER'S REPRESENTATIONS, WARRANTIES AND COVENANTS


         With respect to that certain Option Agreement dated June __, 2001 (the
"AGREEMENT"; all capitalized terms used herein without definition shall have the
meanings ascribed such terms in the Agreement), the Seller hereby represents,
warrants and covenants to Alliance as follows:

         (a)      The Seller has full capacity, power and authority to
countersign and deliver the Agreement (and/or the Stock Transfer Agreement, if
applicable).

         (b)      Without limiting the terms of the investment representations
set forth below, the Seller represents that the Seller has: (i) had an
opportunity to ask questions and receive answers from Alliance and its officers
and directors regarding matters relevant to Alliance and an investment therein;
and (ii) further had the opportunity to obtain any and all information which the
Seller deemed necessary to evaluate Alliance and the investment represented by
the Alliance Shares.

         (c)      The Seller is experienced in making investments in the
unregistered and restricted securities of development stage companies. The
Seller understands that such investments (including that represented by the
Alliance Shares) involve a high degree of speculation and risk. The Seller has
such knowledge and experience in financial and business matters that the Seller
is capable of evaluating the merits and risks of the investment in Alliance
represented by the Alliance Shares and, by reason of the Seller's financial and
business experience, the Seller has the capacity to protect the Seller's
interest in connection with the Securities. The Seller is financially able to
bear the economic risk of the investment represented by the Alliance Shares,
including a total loss of such investment.

         (d)      The Seller is capable of evaluating the risks and merits of
the investment represented by the Alliance Shares and of protecting the Seller's
own interests in connection with such investment.

         (e)      The Seller is an "ACCREDITED INVESTOR" as that term is defined
in Rule 501 promulgated under the Securities Act of 1933, as amended (the
"ACT").

         (f)      The Alliance Shares issued as consideration for the Option
Shares under the Agreement are being and will be acquired by the Seller (i)
solely for investment purposes, (ii) for the Seller's own account only and (iii)
not for sale, transfer or with a view to any distribution of all or any part of
such Alliance Shares. No other person will have any direct or indirect
beneficial interest in the Alliance Shares.

         (g)      The Seller has not engaged any brokers, finders or agents and
has not incurred, and will not incur, directly or indirectly, any liability for
brokerage or finder's fees or agents' commissions or any similar charges in
connection with the Alliance Shares and the transactions contemplated hereby.


                                      D-1
<PAGE>


         (h)      The Seller acknowledges that the Alliance Shares have not been
and will not be, at the time of issuance, registered under the Act or qualified
under the California Corporate Securities Law of 1968, as amended, or any other
applicable blue sky laws in reliance, in part, on the representations and
warranties herein.

         (i)      The Seller understands that (i) the Alliance Shares are
"restricted securities" under the federal securities laws (E.G., the Act)
insofar as the Alliance Shares will be acquired from Alliance in a transaction
not involving a public offering, (ii) under such laws and applicable
regulations, the Alliance Shares may be resold without registration under the
Act only in certain limited circumstances and (iii) in the absence of
registration under the Act (which is not presently contemplated and with respect
to which Alliance has no obligation, except as set forth in Section 5(f) of the
Agreement) the Alliance Shares must be held indefinitely. The Seller understands
the resale limitations imposed by the Act and is familiar with Rule 144 under
the Act, as presently in effect, and the conditions that must be met in order
for Rule 144 to be available with respect to the resale of "restricted
securities." The Seller understands that Alliance may not, from time to time,
meet conditions for the availability of Rule 144 under certain circumstances
(E.G., the provision of current "public Alliance" information).

         (j)      The Seller understands that any certificates evidencing the
Alliance Shares may bear one or all of the following legends:

                  (i)      "THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED. THEY MAY NOT BE SOLD, OFFERED FOR SALE,
TRANSFERRED, PLEDGED OR HYPOTHECATED IN THE ABSENCE OF A REGISTRATION STATEMENT
IN EFFECT WITH RESPECT TO THE SECURITIES UNDER SUCH ACT OR EVIDENCE THAT SUCH
REGISTRATION IS NOT REQUIRED OR UNLESS SOLD PURSUANT TO RULE 144 UNDER SUCH
ACT."

                  (ii)     Any legend required by applicable state securities
laws.

         (k)      Without in any way limiting the representations set forth
above, the Seller further agrees not to make any disposition of all or any
portion of the Alliance Shares purchased hereunder unless and until: (i) there
is then in effect a registration statement under the Act covering such proposed
disposition and such disposition is made in accordance with such registration
statement and any applicable requirements of state securities laws; or (ii) the
Seller shall have (1) notified Alliance of the proposed disposition, (2)
furnished Alliance with a detailed statement of the circumstances surrounding
the proposed disposition and (3) furnished Alliance with a written opinion of
counsel, reasonably satisfactory to Alliance, that such disposition will not
require registration of any securities under the Act or the consent of (or a
permit from) any authority under any applicable state securities laws. Seller
understands that Alliance will not require opinions of counsel for transactions
made pursuant to Rule 144 under the Act provided that Alliance receives all
certificates and other information it may reasonably request to permit it to
determine that the subject disposition is, in fact, exempt from the registration
requirements of the Act pursuant to Rule 144. In the case of any disposition of
any Securities pursuant to Rule 144 under the Act, then in addition to the
matters set forth above, the Seller shall promptly forward to Alliance a copy of
any Form 144 filed with the SEC with respect to such disposition and a letter
from the executing broker satisfactory to Alliance


                                      D-2
<PAGE>


evidencing compliance with Rule 144. If Rule 144 is amended or if the SEC's
interpretations thereof in effect at the time of any such disposition by the
Seller have changed from the SEC's present interpretations thereof, the Seller
shall provide Alliance with such additional documents as Alliance may reasonably
require.


                                      D-3