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                                                                     EXHIBIT 4.1

[COHESION LETTERHEAD]


Cohesion Technologies, Inc.
2500 Faber Place
Palo Alto, CA 94303

ID: 94-3274368

William G. Mavity
[Address of William G. Mavity]

Congratulations! You have been granted a Non-qualified Stock Option to buy
215,000 shares of Cohesion Technologies, Inc. (the Company) stock at $2.70 per
share.

     Grant Date:      9/18/01
     Grant Number:    3908
     Option Plan:     WGM
     Expiration Date: 9/18/11

The total option price of the shares granted is $580,500.00.

Your shares become exercisable over a total of 50 months, as follows:

     24%, or 51,600 shares, on 9/18/02
     76%, or 163,400 shares, at the rate of 2% per month over the following
38 months, ending on 11/18/05.

If you have any questions, please contact Joan Trampenau at x5626.

By your signature and the Company's signature below, you and the Company agree
that these options are granted outside the 1998 Stock Option Plan, but upon
similar terms to the options granted under the 1998 Stock Option Plan.

9/18/01
----------------                        /s/ DEBORAH L. WEBSTER
Date                                    ----------------------------------------
                                        Deborah L. Webster
                                        Cohesion Technologies, Inc.


                                        /s/ WILLIAM G. MAVITY
----------------                        ----------------------------------------
Date                                    William G. Mavity

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                           COHESION TECHNOLOGIES, INC.

                             STOCK OPTION AGREEMENT

     1.   GRANT OF OPTION. Cohesion Technologies, Inc., a Delaware corporation
(the "Company"), hereby grants to the Optionee named in the Notice of Stock
Option Grant attached to this Agreement ("Optionee"), an option (the "Option")
to purchase the total number of shares of Common Stock (the "Shares") set forth
in the Notice of Stock Option Grant, at the exercise price per share set forth
in the Notice of Stock Option Grant (the "Exercise Price").


     2.   EXERCISE OF OPTION. This Option shall be exercisable during its term
in accordance with the Vesting Schedule set out in the Notice of Stock Option
Grant and with the following provisions:

          (a)  RIGHT TO EXERCISE.

               (i)  This Option may not be exercised for a fraction of a share.

               (ii) In the event of Optionee's death, disability or other
termination of employment, the exercisability of the Option is governed by
Sections 6, 7 and 8 below, subject to the limitations contained in paragraphs
(iii) below.

               (iii) In no event may this Option be exercised after the date of
expiration of the term of this Option as set forth in the Notice of Stock Option
Grant.

          (b)  METHOD OF EXERCISE.

               (i)  This Option shall be exercisable by delivering to the
Company a written notice of exercise which shall state the election to exercise
the Option, the number of Shares in respect of which the Option is being
exercised, and such other representations and agreements as to the holder's
investment intent with respect to such Shares of Common Stock as may be required
by the Company. Such written notice shall be signed by Optionee and shall be
delivered in person or by certified mail to the Secretary of the Company. The
written notice shall be accompanied by payment of the Exercise Price. This
Option shall be deemed to be exercised upon receipt by the Company of such
written notice accompanied by the Exercise Price.

               (ii) As a condition to the exercise of this Option, Optionee
agrees to make adequate provision for federal, state or other tax withholding
obligations, if any, which arise upon the exercise of the Option or disposition
of Shares, whether by withholding, direct payment to the Company, or otherwise.

               (iii) No Shares will be issued pursuant to the exercise of an
Option unless such issuance and such exercise shall comply with all relevant
provisions of law and the requirements of any stock exchange upon which the
Shares may then be listed. Assuming such compliance, for income tax purposes the
Shares shall be considered transferred to Optionee on the date on which the
Option is exercised with respect to such Shares.

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     3.   OPTIONEE'S REPRESENTATIONS. In the event the Shares purchasable
pursuant to the exercise of this Option have not been registered under the
Securities Act of 1933, as amended (the "Securities Act"), at the time this
Option is exercised, Optionee shall, if required by the Company, concurrently
with the exercise of all or any portion of this Option, deliver to the Company
an investment representation statement in customary form, a copy of which is
available for Optionee's review from the Company upon request.

     4.   METHOD OF PAYMENT. Payment of the Exercise Price shall be by any of
the following, or a combination of the following, at the election of Optionee:
(a) cash; (b) check; (c) surrender of other Shares of Common Stock of the
Company that (i) either have been owned by Optionee for more than six (6) months
on the date of surrender or were not acquired, directly or indirectly, from the
Company, and (ii) have a Fair Market Value on the date of surrender equal to the
aggregate exercise price of the Shares as to which said Option shall be
exercised; or (d) if there is a public market for the Shares and they are
registered under the Securities Act, delivery of a properly executed exercise
notice together with irrevocable instructions to a broker to deliver promptly to
the Company the amount of sale or loan proceeds required to pay the exercise
price.

     5.   RESTRICTIONS ON EXERCISE. This Option may not be exercised if the
issuance of such Shares upon such exercise or the method of payment of
consideration for such shares would constitute a violation of any applicable
federal or state securities or other law or regulation, including any rule under
Part 207 of Title 12 of the Code of Federal Regulations ("Regulation G") as
promulgated by the Federal Reserve Board. As a condition to the exercise of this
Option, the Company may require Optionee to make any representation and warranty
to the Company as may be required by any applicable law or regulation.

     6.   TERMINATION OF RELATIONSHIP. In the event of termination of Optionee's
Continuous Status as an Employee or Consultant, Optionee may, to the extent
otherwise so entitled at the date of such termination (the "Termination Date"),
exercise this Option, but only within three (3) months from the date of
termination of employment (but in no event later than the date of expiration of
the term of this Option as set forth in Section 10 below). To the extent that
Optionee was not entitled to exercise this Option at the date of such
termination, or if Optionee does not exercise this Option within the time
specified in this Agreement, the Option shall terminate.

     7.   DISABILITY OF OPTIONEE. Notwithstanding the provisions of Section 6
above, in the event of termination of Optionee's Continuous Status as an
Employee or Consultant as a result of total and permanent disability (as defined
in Section 22(e)(3) of the Code), Optionee may, but only within six (6) months
from the date of termination of employment (but in no event later than the date
of expiration of the term of this Option as set forth in Section 10 below),
exercise the Option to the extent otherwise so entitled at the date of such
termination. To the extent that Optionee was not entitled to exercise the Option
at the date of termination, or if Optionee does not exercise such Option (to the
extent otherwise so entitled) within the time specified in this Agreement, the
Option shall terminate.

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     8.   DEATH OF OPTIONEE. In the event of the death of Optionee:

          (a)  during the term of this Option and while an Employee of the
Company and having been in Continuous Status as an Employee or Consultant since
the date of grant of the Option, the Option may be exercised, at any time within
six (6) months following the date of death (but in no event later than the date
of expiration of the term of this Option as set forth in Section 10 below), by
Optionee's estate or by a person who acquired the right to exercise the Option
by bequest or inheritance, but only to the extent of the right to exercise that
would have accrued had Optionee continued living and remained in Continuous
Status as an Employee or Consultant three (3) months after the date of death; or

          (b)  within three (3) months after the termination of Optionee's
Continuous Status as an Employee or Consultant, the Option may be exercised, at
any time within six (6) months following the date of death (but in no event
later than the date of expiration of the term of this Option as set forth in
Section 10 below), by Optionee's estate or by a person who acquired the right to
exercise the Option by bequest or inheritance, but only to the extent of the
right to exercise that had accrued at the date of termination.

     9.   NON-TRANSFERABILITY OF OPTION. This Option may not be transferred in
any manner otherwise than by will or by the laws of descent or distribution. The
designation of a beneficiary does not constitute a transfer. An Option may be
exercised during the lifetime of Optionee only by Optionee or a transferee
permitted by this section. The terms of this Option shall be binding upon the
executors, administrators, heirs, successors and assigns of Optionee.

     10.  TERM OF OPTION. This Option may be exercised only within the term set
out in the Notice of Stock Option Grant, and may be exercised during such term
only in accordance with the terms of this Option.

     11.  NO ADDITIONAL EMPLOYMENT RIGHTS. Optionee understands and agrees that
the vesting of Shares pursuant to the Vesting Schedule is earned only by
continuing as an Employee or Consultant at the will of the Company (not through
the act of being hired, being granted this Option or acquiring Shares under this
Agreement). Optionee further acknowledges and agrees that nothing in this
Agreement shall confer upon Optionee any right with respect to continuation as
an Employee or Consultant with the Company, nor shall it interfere in any way
with his or her right or the Company's right to terminate his or her employment
or consulting relationship at any time, with or without cause.

     12.  TAX CONSEQUENCES. Optionee acknowledges that he or she has read the
brief summary set forth below of certain federal tax consequences of exercise of
this Option and disposition of the Shares under the law in effect as of the date
of grant. OPTIONEE UNDERSTANDS THAT THIS SUMMARY IS NECESSARILY INCOMPLETE, AND
THE TAX LAWS AND REGULATIONS ARE SUBJECT TO CHANGE. OPTIONEE SHOULD CONSULT HIS
OR HER OWN TAX ADVISER BEFORE EXERCISING THIS OPTION OR DISPOSING OF THE SHARES.

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          (a)  EXERCISE OF NONSTATUTORY STOCK OPTION. If this Option does not
qualify as an Incentive Stock Option, Optionee may incur regular federal income
tax liability upon the exercise of the Option. Optionee will be treated as
having received compensation income (taxable at ordinary income tax rates) equal
to the excess, if any, of the fair market value of the Shares on the date of
exercise over the Exercise Price. In addition, if Optionee is an employee of the
Company, the Company will be required to withhold from Optionee's compensation
or collect from Optionee and pay to the applicable taxing authorities an amount
equal to a percentage of this compensation income at the time of exercise.

          (b)  DISPOSITION OF SHARES. If this Option is a Nonstatutory Stock
Option, then gain realized on the disposition of Shares will be treated as
long-term or short-term capital gain depending on whether or not the disposition
occurs more than one year after the exercise date. In the case of a Nonstatutory
Stock Option, the long-term capital gain will be taxed for federal income tax
and alternative minimum tax purposes at a maximum rate of 20% if the Shares are
held more than 12 months after exercise.

     13.  SIGNATURE. This Stock Option Agreement shall be deemed executed by the
Company and Optionee upon execution by such parties of the Notice of Stock
Option Grant attached to this Stock Option Agreement.

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