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                                                                   EXHIBIT 10.26

                            PLANET TECHNOLOGIES, INC.

February 1, 2005

Bret Megargel
3912 Alameda Place
San Diego, CA 92103

Dear Bret,

Planet Technologies, Inc. (the "Company") is pleased to offer you the position
of Vice President Marketing and Business Development, pursuant to the terms of
this letter agreement ("Agreement"). This Agreement is effective February 1,
2005 (the "Effective Date"). You and the Company hereby agree as follows:

1.    DUTIES

You will be expected to do and perform all services, acts or things necessary or
advisable to manage and conduct the business of the Company, including those
duties normally associated with your position. You will report to the Company's
President and Chief Executive Officer and will work at our facility in San
Diego, California.

2.    BASE SALARY AND BENEFITS

Your base salary will be $6,000 per month for February and March, increasing to
$8,000 per month on April 1, 2005, less payroll deductions and all required
withholdings payable semi-monthly. You will be eligible for the Company's
standard benefits, which will be available to you the first of the month
following your date of hire. The benefits will include Medical and Dental
Insurance (unless waived).

3.    STOCK OPTIONS

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Subject to approval of the Board, you will be granted a stock option under the
terms of the Company's 2000 Equity Incentive Plan (the "Plan") to purchase
30,000 shares of the Company's Common Stock (the "Option"). The Option shall be
an Incentive Stock Option as such term is defined in Section 422 of the Internal
Revenue Code of 1986, as amended. The Option will be governed by and granted
pursuant to a separate Stock Option Agreement and the Plan. The exercise price
per share of the Option will be $3.00 per share, which is the fair market value
of the Common Stock established on the date of grant. The Option will be subject
to vesting over four (4) years so long as you provide continuous service to the
Company in accordance with the Plan, according to the following schedule: 1/4 of
the shares subject to the Option will vest upon your 12 month anniversary and
1/48th of the shares subject to the Option will vest at the end of each monthly
period thereafter for a period of three (3) years.

4.    Bonus

As a bonus for the year 2005, the board has approved an acceleration clause in
your options:

      a.)   If the planned acquisition is completed in this calendar year, 50%
            of the shares in your option will become fully vested.

      b.)   If in the sole opinion of the President/CEO, you complete the
            transition and integration by calendar year end into one facility,
            the remaining shares in the option will become vested.

5.    LOYAL AND CONSCIENTIOUS PERFORMANCE; NONCOMPETITION.

During your employment by the Company, you shall devote the required business
energies, interest, abilities and productive time to the proper and efficient
performance of your duties under this Agreement. We recognize that you may also
provide services to other companies and this is a part time position. Such
activities are acceptable as long as they do not present any conflict of
interest with the Company.

Except with the prior written consent of the Board, you will not, during the
term of this Agreement, and any period during which you are receiving
compensation or any other consideration from the Company, including, but not
limited to, severance pay pursuant to Section 6 herein, engage in competition
with the Company, either directly or indirectly, in any manner or capacity, as
adviser, principal, agent, affiliate, promoter, partner, officer, director,
employee, stockholder, owner, co-owner, consultant, or member of any association
or otherwise, in any phase of the business of developing, manufacturing and
marketing of products or services which are in the same field of use or which
otherwise compete with the products or services or proposed products or services
of the Company.

During the term of this Agreement, you agree not to acquire, assume or
participate in, directly or indirectly, any position, investment or interest
known by you to be adverse or antagonistic to the Company, its business or
prospects, financial or otherwise or in any company, person or entity that is,
directly or indirectly, in competition with the business of the Company.
Ownership by you, as a passive investment, of less than two percent (2%) of the
outstanding shares of capital

                                       2.
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stock of any corporation with one or more classes of its capital stock listed on
a national securities exchange or publicly traded on the Nasdaq Stock Market or
in the over-the-counter market shall not constitute a breach of this paragraph.

6.    TERMINATION

The Company may terminate your employment at any time and for any or no reason,
with or without Cause (as defined herein) or advance notice by giving written
notice of such termination, subject to the provisions stated herein. Similarly,
you may terminate your employment with the Company at any time at your election,
in your sole discretion, for any or no reason. The "at will" nature of your
employment relationship may not be modified except by a written agreement signed
by the President/CEO.

7.    PROPRIETARY INFORMATION AND INVENTIONS AGREEMENT

As a condition of employment, you will be required to sign and comply with the
Proprietary Information and Inventions Agreement, attached hereto as Exhibit A,
which prohibits unauthorized use or disclosure of the Company's proprietary
information, among other things.

In your work for the Company, you will be expected not to use or disclose any
confidential information, including trade secrets, of any former employer or
other person to whom you have an obligation of confidentiality. Rather, you will
be expected to use only that information which is generally known and used by
persons with training and experience comparable to your own, which is common
knowledge in the industry or otherwise legally in the public domain, or which is
otherwise provided or developed by the Company. During our discussions about
your proposed job duties, you assured us that you would be able to perform those
duties within the guidelines just described.

You agree that you will not bring onto Company premises any unpublished
documents or property belonging to any former employer or other person to whom
you have an obligation of confidentiality.

8.    ENTIRE AGREEMENT

This Agreement, together with your Proprietary Information and Inventions
Agreement and the stock documents referred to herein, forms the complete and
exclusive statement of the terms of your employment with the Company. The
employment terms in this Agreement supersede any other agreements or promises
made to you by anyone, whether oral or written.

9.    GOVERNING LAW

This Agreement will be governed by and construed according to the laws of the
State of California. You hereby expressly consent to the personal jurisdiction
of the state and federal courts located in San Diego, California for any lawsuit
filed there against you by the Company arising from or related to this
Agreement.

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10. SUCCESSORS AND ASSIGNS. This Agreement will be binding upon your heirs,
executors, administrators and other legal representatives and will be binding
upon and shall inure to the benefit of the Company, its successors, and its
assigns. The term "Company" as used herein shall include such successors and
assigns to the extent applicable.

As required by law, this offer is subject to satisfactory proof of your right to
work in the United States.

Please sign and date this Agreement, and return it to me as soon as possible, if
you wish to accept employment with the Company under the terms described above.

We look forward to your favorable reply and to a productive and enjoyable work
relationship.

Sincerely,

PLANET TECHNOLOGIES, INC.

 By:________________________________________

     SCOTT L. GLENN
     PRESIDENT AND CHIEF EXECUTIVE OFFICER

Accepted:

____________________________________________

____________________________________________
Date

Attachment: Exhibit A:  Proprietary Information and Inventions Agreement

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                                    EXHIBIT A

          EMPLOYEE'S PROPRIETARY INFORMATION AND INVENTIONS AGREEMENT

      In consideration of my employment or continued employment by PLANET
TECHNOLOGIES, INC. (the "COMPANY"), and the compensation received by me from the
Company from time to time, I hereby agree as follows:

11.   PROPRIETARY INFORMATION.

      (a) RECOGNITION OF COMPANY'S RIGHTS. All Proprietary Information shall be
the sole property of the Company and its assignees. I hereby assign to the
Company any rights I may have or acquire in all Proprietary Information. At all
times during my employment by the Company and at all times after termination of
such employment, I will keep in confidence and trust all Proprietary
Information, and I will not disclose, sell, use, lecture upon or publish any
Proprietary Information or anything relating to it without the written consent
of the Company, except as may be necessary in the ordinary course of performing
my duties as an employee of the Company, or unless an officer of the Company
expressly authorizes such in writing.

      (b) PROPRIETARY INFORMATION. The term "PROPRIETARY INFORMATION" shall mean
any and all confidential and/or proprietary knowledge, data or information of
the Company, whether in oral, written, graphic or electronic form. By way of
illustration, but not limitation, "PROPRIETARY INFORMATION" includes (a) trade
secrets, know-how, inventions, ideas, tangible and intangible information
relating to antibodies and other biological materials, cell lines, samples of
assay components, media and/or cell lines and procedures and formulations for
producing any such assay components, media and/or cell lines, formulations,
compounds, products, processes, designs, formulas, methods, techniques,
programs, software models, algorithms, developmental or experimental work,
clinical or other data, compilations of data, other works of authorship,
improvements and discoveries (hereinafter collectively referred to as
"INVENTIONS"); (b) information regarding plans for research and development, new
products, marketing and selling, business plans, budgets and unpublished
financial statements, licenses, prices and costs, suppliers, customers,
licensees and strategic partners, and the existence and terms of any business
discussions, negotiations or agreements to which the Company is a party; and (c)
information regarding the skills and compensation of other employees or
consultants of the Company.

      (c) NO IMPROPER USE OF INFORMATION OF PRIOR EMPLOYERS AND OTHERS. I
represent that I have not brought and will not bring with me to the Company or
use in the performance of my responsibilities at the Company any equipment,
supplies, facility or trade secret information of any former employer or any
other person to whom I have an obligation of confidentiality which is not
generally available to the public, unless I have obtained written authorization
for its possession and use.

                                       5.
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12.   ASSIGNMENT OF INVENTIONS.

      (a) The term "PROPRIETARY RIGHTS" shall mean all trade secrets, patents,
copyrights, trademarks, mask works, moral rights and other intellectual property
rights throughout the world.

      (b) ASSIGNMENT OF INVENTIONS. Subject to Sections 2(f) and 2(g), I agree
that all Inventions (and all Proprietary Rights with respect thereto) shall be
the sole property of the Company and its assigns. I hereby assign to the Company
any right, title and interest I may have or acquire in and to all Inventions
(and all Proprietary Rights with respect thereto). If I have any rights to the
Inventions (or Proprietary Rights with respect thereto) that cannot be assigned
to the Company, I unconditionally and irrevocably waive the enforcement of such
rights and all claims and causes of action of any kind against the Company with
respect to such rights. I agree, at the Company's request and expense, to
consent to and join in any action to enforce such rights. If I have any right to
the Inventions (or Proprietary Rights with respect thereto) that cannot be
assigned to the Company or waived by me, I unconditionally and irrevocably grant
to the Company during the term of such rights, an exclusive, irrevocable,
perpetual, worldwide, fully paid and royalty-free license, with rights to
sublicense through multiple levels of sublicensees, to make, have made, use,
offer for sale, sell, import, reproduce, create derivative works of, distribute,
publicly perform and publicly display by all means now known or later developed,
such rights.

      (c) ASSISTANCE. I further agree to assist the Company in every proper way
(but at the Company's expense) to obtain, and from time to time enforce, the
Proprietary Rights in any and all Inventions, including, but not limited to
applying for and obtaining such patents thereon and enforcing same, as the
Company may desire, together with any assignments thereof to the Company or
persons designated by it. My obligation to assist the Company in obtaining and
enforcing Proprietary Rights in the Inventions in any and all countries shall
continue beyond the termination of my employment, but the Company shall
compensate me at a reasonable rate after such termination for time actually
spent by me at the Company's request on such assistance. In the event that the
Company is unable for any reason whatsoever to secure my signature to any lawful
and necessary document required to obtain or enforce any Proprietary Rights with
respect to any Invention (including renewals, extension, continuations,
divisions or continuations in part thereof), I hereby irrevocably designate and
appoint the Company and its duly authorized officers and agents, as my agents
and attorneys-in-fact to act for and in my behalf and instead of me, to execute
and file any such documents and to do all other lawfully permitted acts to
further execution or enforcement of Proprietary Rights with the same legal force
and effect as if executed by me.

      (d) PRIOR INVENTIONS. As a matter of record I have attached hereto as
EXHIBIT A a complete list of all inventions or improvements which have been made
or conceived or first reduced to practice by me, alone or jointly with others,
prior to the commencement of my employment by the Company which I desire to
remove from the operation of this Agreement (collectively referred to as "PRIOR
INVENTIONS"); and I covenant that such list is complete. If disclosure of any
such Prior Inventions would cause me to violate any prior confidentiality
agreement, I understand that I should not list such Prior Invention in EXHIBIT A
but will disclose a cursory name for each such invention, a listing of the
party(ies) to whom it belongs, and the fact

                                       6.
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that full disclosure as to such Prior Invention has not been made for that
reason. If no such disclosure is attached to this Agreement, I represent that I
have made no such inventions and improvements at the time of signing this
Agreement. If, in the course of my employment with the Company, I incorporate a
Prior Invention into an Invention or a Company product or process, the Company
is hereby granted and shall have a nonexclusive, royalty-free, irrevocable,
perpetual, worldwide license (with rights to sublicense through multiple tiers
of sublicensees) to make, have made, use, offer for sale, sell, import,
reproduce, create derivative works of, distribute, publicly perform and publicly
display by all means now known or later developed such Prior Invention.
Notwithstanding the foregoing, I agree that I will not incorporate, or permit to
be incorporated, Prior Inventions in any Invention or Company product or process
without the Company's prior written consent.

      (e) OBLIGATION TO KEEP COMPANY INFORMED. I will promptly and fully in
writing disclose to the Company all Inventions authored, conceived or reduced to
practice or learned by me, either alone or jointly with others, during the
period of my employment and for one (1) year after termination of this
Agreement, including any that may be covered by Section 2870 of the California
Labor Code.

      (f) GOVERNMENT OR THIRD PARTY. I also agree to assign all my right, title
and interest in and to any particular Invention to a third party, including
without limitation the United States, as directed by the Company.

      (g) NONASSIGNABLE INVENTIONS. This Agreement does not apply to inventions
which qualify fully for protection under Section 2870 of the California Labor
Code, which are ideas or inventions for which no equipment, supplies, facility
or trade secret information of the Company was used and which were developed
entirely on my own time, and (1) which do not relate (a) directly to the
business of the Company, or (b) to the Company's actual or demonstrably
anticipated research or development, or (2) which do not result from any work
performed by me for the Company. Notwithstanding the foregoing, I shall disclose
in confidence to the Company any invention in order to permit the Company to
make a determination as to compliance by me with the terms and conditions of
this Agreement.

13. NO CONFLICT OF INTEREST. I agree that during the period of my employment by
the Company and any period during which I am receiving compensation or any other
consideration from the Company, including, but not limited to, any severance
pay, I will not, without the Company's prior written consent, engage in any
employment or business activity which is competitive with the business of the
Company or any of its affiliates, either directly or indirectly, in any manner
or capacity, as adviser, principal, agent, affiliate, promoter, partner,
officer, director, employee, stockholder, owner, co-owner, consultant or
otherwise, in any phase of the business of developing, manufacturing and
marketing of products or services which are in the same field of use or which
otherwise compete with the products or services or proposed products or services
of the Company or any of its affiliates. My ownership, as a passive investment,
of less than two percent (2%) of the outstanding shares of capital stock of any
corporation with one or more classes of its capital stock listed on a national
securities exchange or publicly traded on the Nasdaq Stock Market or in the
over-the-counter market shall not constitute a breach of this Section 3.

                                       7.
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14. NON-SOLICITATION. I agree that for a period of one (1) year following
termination of my employment with the Company, I will not solicit or in any
manner encourage any employee, independent contractor or consultant of the
Company to leave employment or service with the Company.

15. NO CONFLICTING OBLIGATIONS. I represent that my performance of all the terms
of this Agreement and that my employment by the Company do not and will not
breach any agreement to keep in confidence proprietary information acquired by
me in confidence or in trust prior to my employment by the Company. I have not
entered into, and I agree I will not enter into, any agreement either written or
oral in conflict herewith.

16. RETURN OF COMPANY MATERIALS. All drawings, notes, memoranda, specifications,
documents, data, devices, records, apparatus, equipment, chemicals, molecules,
organisms and other physical property, including any copies thereof, whether or
not pertaining to Proprietary Information, furnished to me by the Company or
produced by myself or others in connection with my employment shall be and
remain the sole property of the Company and shall be returned promptly to the
Company upon termination of this Agreement for any reason, or earlier if
requested by the Company, and I will not retain or take with me any such
property or any reproduction of such property.

17. GENERAL PROVISIONS.

      (a) Any notices required or permitted hereunder shall be given to the
appropriate party at the address specified below or at such other address as the
party shall specify in writing. Such notice shall be in writing and shall be
deemed given (i) upon personal delivery to the appropriate address, (ii) upon
delivery by facsimile transmission with receipt confirmed, (iii) if sent by
certified or registered mail, postage prepaid, three (3) days after the date of
mailing, or (iv) if sent by overnight courier, the next business day such
courier regularly makes deliveries.

      (b) This Agreement will be governed by and construed according to the laws
of the State of California, as such laws are applied to agreements entered into
and to be performed entirely within the State of California between California
residents. I hereby expressly consent to the personal jurisdiction of the state
and federal courts located in San Diego County, California for any lawsuit filed
there against me by Company arising from or related to this Agreement.

      (c) Because my services are personal and unique and because I may have
access to and become acquainted with the Proprietary Information of the Company,
I acknowledge and agree that, if I were to breach this Agreement, the Company
would suffer an irreparable injury such that no remedy at law would adequately
protect or appropriately compensate the Company for such injury. Accordingly, I
agree that the Company shall have the right to enforce this Agreement and any of
its provisions by injunction, specific performance or other equitable relief,
without bond and without prejudice to any other rights and remedies that the
Company may have for a breach of this Agreement.

      (d) This Agreement (including any exhibits hereto) contains the final,
complete and exclusive agreement of the parties relative to the subject matter
hereof and supersedes all prior

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and contemporaneous understandings and agreements relating to said subject
matter. This Agreement may not be changed, modified, amended or supplemented
except by a written instrument signed by both parties.

      (e) If any provision of this Agreement shall be declared invalid, illegal
or unenforceable, such provision shall be severed and all remaining provisions
shall continue in full force and effect.

      (f) This Agreement shall be binding upon my heirs, executors,
administrators and other legal representatives and me and shall inure to the
benefit of the Company, its successors and assigns.

      (g) The waiver from time to time by the Company of any of its rights or
the Company's failure to exercise any remedy shall not operate or be construed
as a continuing waiver of same or of any other of the Company's rights or
remedies provided in this Agreement.

      (h) I agree and understand that nothing in this Agreement shall confer any
right with respect to continuation of employment by the Company, nor shall it
interfere in any way with my right or the Company's right to terminate my
employment at any time, with or without cause, nor shall it obligate the Company
to make any payment to me based upon termination of my employment.

This Agreement shall be effective as of the first day of my employment by the
Company.

Dated: ___________________, 2004              By: ______________________________

                                              Printed Name: ____________________

                                              Title: ___________________________

ACCEPTED AND AGREED TO:

PLANET TECHNOLOGIES, INC.

By:       _____________________________________
          Scott L. Glenn
          President and Chief Executive Officer

Address:  6402 Cardeno Drive
          La Jolla, CA  92037

                                       9.
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                                    EXHIBIT A

TO:      PLANET TECHNOLOGIES, INC.

FROM:    ___________________

DATE:    ___________________

SUBJECT: PREVIOUS INVENTIONS

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1. Except as listed in Section 2 below, the following is a complete list of all
inventions or improvements relevant to the subject matter of my employment by
Planet Technologies, Inc. (the "COMPANY") that have been made or conceived or
first reduced to practice by me alone or jointly with others prior to my
engagement by the Company:

      [ ] No inventions or improvements.

      [ ] See below:

          ______________________________________________________________________

          ______________________________________________________________________

          ______________________________________________________________________

[ ]   Additional sheets attached.

      2. Due to a prior confidentiality agreement, I cannot complete the
disclosure under Section 1 above with respect to inventions or improvements
generally listed below, the proprietary rights and duty of confidentiality with
respect to which I owe to the following party(ies):

      INVENTION OR IMPROVEMENT          PARTY(IES)          RELATIONSHIP

1.    ___________________________       ______________      ____________________

2.    ___________________________       ______________      ____________________

3.    ___________________________       ______________      ____________________

[ ]   Additional sheets attached.

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By signing below, I acknowledge that I have read this Agreement document
carefully, understand it fully and agree to its terms and conditions. I
understand that signing this Agreement is a condition of employment

Print Name

Signature                                    Date

                                       2.