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                                                                   EXHIBIT 10.39

                                    WARRANT
                      TO PURCHASE SHARES OF COMMON STOCK
                                      OF
                      PROTEIN POLYMER TECHNOLOGIES, INC.



THE WARRANTS REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AND NEITHER THESE WARRANTS NOR ANY INTEREST THEREIN MAY
BE TRANSFERRED, HYPOTHECATED OR OTHERWISE DISPOSED OF WITHOUT REGISTRATION UNDER
THAT ACT OR AN OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY THAT SUCH
REGISTRATION IS NOT REQUIRED.

No. G-__                                     Warrant to Purchase _______ Shares
August __, 1999                                 of Common Stock, $.01 Par Value



                       WARRANT TO PURCHASE COMMON STOCK
                                      of
                      PROTEIN POLYMER TECHNOLOGIES, INC.,
                            a Delaware corporation
          Void after the date set forth in the first paragraph hereof



          This certifies that, for value received, ______________, or registered
assigns ("Holder") is entitled, subject to the terms set forth below, to
          ------
purchase from Protein Polymer Technologies, Inc., a Delaware corporation (the

"Company"), ______ shares of Common Stock, $.01 par value, of the Company (such
--------
class of stock being referred to herein as "Common Stock"), as constituted on
                                            ------------
August ___, 1999  (the "Issue Date"), upon surrender of this Warrant, at the
principal office of the Company referred to below, with the subscription form
attached hereto duly executed, and simultaneous payment therefor in the
consideration specified in Section 1 hereof, at the price of $0.50 per share
(the "Purchase Price").  This Warrant must be exercised, if at all, prior to the
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last day of the twelfth calendar month after the Issue Date.  The shares of
Common Stock issued or issuable upon exercise of this Warrant are sometimes
referred to as the "Warrant Shares."  The term "Warrants" as used herein shall
                    --------------              --------
include this Warrant and any warrants delivered in substitution or exchange
therefor as provided herein.

          1.  Exercise.  This Warrant may be exercised at any time or from time
              --------
to time, on any business day, for all or part of the full number of shares of
Common Stock during the period of time called for hereby, by surrendering it at
the principal office of the Company, 10655 Sorrento Valley Road, First Floor,
San Diego, California 92121, with the subscription form duly executed, together
with payment for the Warrant Shares payable in cash, by check for same day funds
and/or by delivery and cancellation of promissory notes evidencing indebtedness
of the Company.  No other form of
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consideration shall be acceptable for the exercise of this Warrant. A Warrant
shall be deemed to have been exercised immediately prior to the close of
business on the date of its surrender for exercise as provided above, and the
person entitled to receive the shares of Common Stock issuable upon such
exercise shall be treated for all purposes as the holder of such shares of
record as of the close of business on such date. As soon as practicable on or
after such date, and in any event within 10 days thereof, the Company shall
issue and deliver to the person or persons entitled to receive the same a
certificate or certificates for the number of shares of Common Stock issuable
upon such exercise. Upon any partial exercise, the Company will issue and
deliver to Holder a new Warrant or Warrants with respect to the shares of Common
Stock not so transferred. No fractional shares of Common Stock shall be issued
upon exercise of a Warrant. In lieu of any fractional share to which Holder
would be entitled upon exercise, the Company shall pay cash equal to the product
of such fraction multiplied by the Common Stock Value (as defined in the
Company's Certificate of Designation of Series G Preferred Stock) on the date of
exercise.

          2.  Payment of Taxes.  All shares of Common Stock issued upon the
              ----------------
exercise of a Warrant shall be duly authorized, validly issued and outstanding,
fully paid and non-assessable.  Holder shall pay all taxes and other
governmental charges that may be imposed in respect of the issue or delivery
thereof and any tax or other charge imposed in connection with any transfer
involved in the issue of any certificate for shares of Common Stock in any name
other than that of the registered Holder of the Warrant surrendered in
connection with the purchase of such shares, and in such case the Company shall
not be required to issue or deliver any stock certificate until such tax or
other charge has been paid or it has been established to the Company's
satisfaction that no tax or other charge is due.


          3.  Transfer and Exchange.  This Warrant and all rights hereunder are
              ---------------------
transferable, in whole but not in part, only with the prior approval of the
Company, which consent shall not be unreasonably withheld.  If such a proposed
transfer is so approved, this Warrant is transferable on the books of the
Company maintained for such purpose at its principal office referred to above by
Holder in person or by duly authorized attorney, upon surrender of this Warrant
properly endorsed and upon payment of any necessary transfer tax or other
governmental charge imposed upon such transfer.  Each taker and holder of this
Warrant, by taking or holding the same, consents and agrees that this Warrant,
when endorsed in blank, shall be deemed negotiable and that when this Warrant
shall have been so endorsed, the Holder hereof may be treated by the Company and
all other persons dealing with this Warrant as the absolute owner hereof for any
purpose and as the person entitled to exercise the rights represented hereby or
to the transfer hereof on the books of the Company, any notice to the contrary
notwithstanding; but until such transfer on such books, the Company may treat
the registered Holder hereof as the owner for all purposes.

          4.  Certain Adjustments.
              -------------------

              4.1  Adjustment for Reorganization, Consolidation, Merger. In case
                   ----------------------------------------------------
of any reorganization of the Company (or any other corporation, the stock or
other securities of which are at the time receivable on the exercise of this
Warrant) after the

                                      -2-
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Issue Date, or in case, after such date, the Company (or any such other
corporation) shall consolidate with or merge into another corporation (other
than the merger of a wholly owned subsidiary into the Company) or convey all or
substantially all its assets to another corporation, then and in each such case
Holder, upon the exercise hereof as provided in Section 1 at any time after the
consummation of such reorganization, consolidation, merger or conveyance, shall
be entitled to receive, in lieu of the stock receivable upon the exercise of
this Warrant prior to such consummation, the stock or other securities or
property to which such Holder would have been entitled upon such consummation if
such Holder had exercised this Warrant immediately prior thereto.

              4.2  Adjustments for Dividends in Common Stock. If the Company at
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any time or from time to time after the Issue Date makes, or fixes a record date
for the determination of holders of Common Stock entitled to receive, a dividend
payable in additional shares of Common Stock, then and in each such event the
Purchase Price then in effect shall be decreased as of the time of such issuance
or, in the event such record date is fixed, as of the close of business on such
record date, by multiplying the Purchase Price then in effect by a fraction (1)
the numerator of which is the total number of shares of Common Stock issued and
outstanding immediately prior to the time of such issuance or the close of
business on such record date, and (2) the denominator of which shall be the
total number of shares of Common Stock issued and outstanding immediately prior
to the time of such issuance or the close of business on such record date plus
the number of shares of Common Stock issuable in payment of such dividend;
provided, however, that if such record date is fixed and such dividend is not
fully paid on the date fixed therefor, the Purchase Price shall be recomputed
accordingly as of the close of business on such record date and thereafter the
Purchase Price shall be adjusted pursuant to this Section 4.2 as of the time of
actual payment of such dividends.

              4.3  Stock Split and Reverse Stock Split. If the Company at any
                   -----------------------------------
time or from time to time after the Issue Date effects a subdivision of the
outstanding Common Stock, the Purchase Price then in effect immediately before
that subdivision shall be proportionately decreased and the number of shares of
Common Stock theretofore receivable upon the exercise of this Warrant shall be
proportionately increased. If the Company at any time or from time to time after
the Issue Date combines the outstanding shares of Common Stock into a smaller
number of shares, the Purchase Price then in effect immediately before that
combination shall be proportionately increased and the number of shares of
Common Stock theretofore receivable upon the exercise of this Warrant shall be
proportionately decreased. Each adjustment under this Section 4.3 shall become
effective at the close of business on the date the subdivision or combination
becomes effective.

              4.4  Accountants' Certificate as to Adjustment. In each case of an
                   -----------------------------------------
adjustment in the shares of Common Stock receivable on the exercise of the
Warrants, the Company at its expense shall cause independent public accountants
of recognized standing selected by the Company (who may be the independent
public accountants then auditing the books of the Company) to compute such
adjustment in accordance with the terms of the Warrants and prepare a
certificate setting forth such adjustment and showing the facts upon which such
adjustment is based. The Company will forthwith mail a copy of each such
certificate to each holder of a Warrant at the time outstanding.

                                      -3-
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          5.  Loss or Mutilation.  Upon receipt by the Company of evidence
              ------------------
satisfactory to it (in the exercise of reasonable discretion) of the ownership
of and the loss, theft, destruction or mutilation of any Warrant and (in the
case of loss, theft or destruction) of indemnity satisfactory to it (in the
exercise of reasonable discretion), and (in the case of mutilation) upon
surrender and cancellation thereof, the Company will execute and deliver in lieu
thereof a new Warrant of like tenor.

          6.  Reservation of Common Stock.  The Company shall at all times
              ---------------------------
reserve and keep available out of its authorized but unissued shares of Common
Stock, solely for the purpose of effecting the exercise of the Warrant, such
number of its shares of Common Stock as shall from time to time be sufficient to
effect exercise of the Warrant; and if at any time the number of authorized but
unissued shares of Common Stock shall not be sufficient to effect such exercise,
the Company will take such corporate action as may, in the opinion of its
counsel, be necessary to increase its authorized but unissued shares of Common
Stock to such number of shares as shall be sufficient for such purpose.

          7.  Notices of Record Date.  In the event of (i) any taking by the
              ----------------------
Company of a record of the holders of any class of securities for the purpose of
determining the holders thereof who are entitled to receive any dividend or
other distribution, or (ii) any capital reorganization of the Company, any
reclassification or recapitalization of the capital stock of the Company, any
merger or consolidation of the Company with or into any other corporation (other
than a merger of a wholly owned subsidiary into the Company), or any transfer of
all or substantially all of the assets of the Company to any other person or any
voluntary or involuntary dissolution, liquidation or winding up of the Company,
the Company shall mail to the Holder at least thirty (30) days prior to the
record date specified therein, a notice specifying (1) the date on which any
such record is to be taken for the purpose of such dividend or distribution and
a description of such dividend or distribution, (2) the date on which any such
reorganization, reclassification, transfer, consolidation, merger, dissolution,
liquidation or winding up is expected to become effective, and (3) the date, if
any, that is to be fixed, as to when the holders of record of Common Stock (or
other securities) shall be entitled to exchange their shares of Common Stock (or
other securities) for securities or other property deliverable upon such
reorganization, reclassification, transfer, consolidation, merger, dissolution,
liquidation or winding up.

          8.  Investment Representation and Restriction on Transfer.
              -----------------------------------------------------

              8.1  Securities Law Requirements.
                   ---------------------------

                   (a)  By its acceptance of this Warrant, Holder hereby
represents and warrants to the Company that this Warrant and the Warrant Shares
will be acquired for investment for its own account, not as a nominee or agent,
and not with a view to the sale or distribution of any part thereof, and that it
has no present intention of selling, granting participations in or otherwise
distributing the same. By acceptance of this Warrant, Holder further represents
and warrants that it does not have any contract, undertaking, agreement or
arrangement with any person to sell, transfer or grant participations to any
person, with respect to this Warrant or the Warrant Shares.

                                      -4-
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                   (b)  By its acceptance of this Warrant, Holder understands
that this Warrant is not, and the Warrant Shares will not be, registered under
the Securities Act of 1933, as amended (the "Act"), on the basis that the
issuance of this Warrant and the Warrant Shares are exempt from registration
under the Act pursuant to Section 4(2) thereof, and that the Company's reliance
on such exemption is predicated on Holder's representations and warranties set
forth herein.

                   (c)  By its acceptance of this Warrant, Holder understands
that the Warrant and the Warrant Shares may not be sold, transferred, or
otherwise disposed of without registration under the Act, or an exemption
therefrom, and that in the absence of an effective registration statement
covering the Warrant and the Warrant Shares or an available exemption from
registration under the Act, the Warrant and the Warrant Shares must be held
indefinitely. In particular, Holder is aware that the Warrant and the Warrant
Shares may not be sold pursuant to Rule 144 promulgated under the Act unless all
of the conditions of Rule 144 are satisfied. Among the conditions for use of
Rule 144 are the availability of current information about the Company to the
public, prescribed holding periods which will commence only upon Holder's
payment for the securities being sold, manner of sale restrictions, volume
limitations and certain other restrictions. By its acceptance of this Warrant,
Holder represents and warrants that, in the absence of an effective registration
statement covering the Warrant or the Warrant Shares, it will sell, transfer or
otherwise dispose of the Warrant and the Warrant Shares only in a manner
consistent with its representations and warranties set forth herein and then
only in accordance with the provisions of Section 8.1(d).

                   (d)  By its acceptance of this Warrant, Holder agrees that in
no event will it transfer or dispose of any of the Warrants or the Warrant
Shares other than pursuant to an effective registration statement under the Act,
unless and until (i) Holder shall have notified the Company of the proposed
disposition and shall have furnished the Company with a statement of the
circumstances surrounding the disposition, and (ii) if reasonably requested by
the Company, at the expense of the Holder or transferee, it shall have furnished
to the Company an opinion of counsel, reasonably satisfactory to the Company, to
the effect that (A) such transfer may be made without registration under the Act
and (B) such transfer or disposition will not cause the termination or the non-
applicability of any exemption to the registration and prospectus delivery
requirements of the Act or to the qualification or registration requirements of
the securities laws of any other jurisdiction on which the Company relied in
issuing the Warrant or the Warrant Shares.

              8.2  Legends; Stop Transfer.
                   ----------------------

                   (a)  All certificates evidencing the Warrant Shares shall
bear a legend in substantially the following form:

          The securities represented by this certificate have not been
          registered under the Securities Act of 1933.  These securities have
          been acquired for investment and not with a view to distribution and
          may not be offered for sale, sold, pledged or otherwise transferred in
          the absence of an effective registration statement for such securities
          under the Securities Act of 1933 or an opinion of counsel reasonably
          satisfactory in form and content to the issuer that such registration
          is not required under such Act.

                                      -5-
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                   (b)  The certificates evidencing the Warrant Shares shall
also bear any legend required by any applicable state securities law.

                   (c)  In addition, the Company shall make, or cause its
transfer agent to make, a notation regarding the transfer restrictions of the
Warrant and the Warrant Shares in its stock books, and the Warrant and the
Warrant Shares shall be transferred on the books of the Company only if
transferred or sold pursuant to an effective registration statement under the
Act covering the same or pursuant to and in compliance with the provisions of
Section 8.1(d).

          9.  Notices.  All notices and other communications from the Company to
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the Holder of this Warrant shall be mailed by first-class registered or
certified mail, postage prepaid, to the address furnished to the Company by
Holder.

          10. Change; Waiver.  Neither this Warrant nor any term hereof may be
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changed, waived, discharged or terminated orally, but only by an instrument in
writing signed by the party against which enforcement of the change, waiver,
discharge or termination is sought.

          11. Headings.  The headings in this Warrant are for purposes of
              --------
convenience in reference only, and shall not be deemed to constitute a part
hereof.

          12. Governing Law. This Warrant is delivered in California and shall
              -------------
be construed and enforced in accordance with and governed by the internal laws,
and not the law of conflicts, of such State; provided however, that to the
extent that an issue of determination is one of corporation law, then the
Delaware General Corporation Law shall govern.

                            PROTEIN POLYMER TECHNOLOGIES, INC.,
                            A DELAWARE CORPORATION



                            By______________________________________
                            J. Thomas Parmeter, President

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                               SUBSCRIPTION FORM
                               -----------------
                (To be executed only upon exercise of Warrant)


          The undersigned, registered owner of this Warrant, irrevocably
exercises this Warrant and purchases ____________ of the number of shares of
Common Stock, $.01 par value, of PROTEIN POLYMER TECHNOLOGIES, INC., a Delaware
corporation, purchasable with this Warrant, and herewith makes payment therefor,
all at the price and on the terms and conditions specified in this Warrant.

DATED:______________


                         ---------------------------------------
                         (Signature of Registered Owner)


                         ---------------------------------------
                         (Street Address)


                         ---------------------------------------
                         (City)        (State)    (Zip)
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                              FORM OF ASSIGNMENT
                              ------------------

          FOR VALUE RECEIVED the undersigned, registered owner of this Warrant,
hereby sells, assigns and transfers unto the Assignee named below all of the
rights of the undersigned under the within Warrant, with respect to the number
of shares of Common Stock, $.01 par value, set forth below:

Name of Assignee                Address                 No. of Shares
----------------                -------                 -------------



and does hereby irrevocably constitute and appoint _________________________
_________________________________________________ Attorney to make such transfer
on the books of PROTEIN POLYMER TECHNOLOGIES, INC., a Delaware corporation,
maintained for the purpose, with full power of substitution in the premises.

DATED: ___________________


                                -------------------------------
                                    (Signature)


                                --------------------------------
                                    (Witness)