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                                                                  EXHIBIT 10.23

                                                                  EXECUTION COPY




                               SECURITY AGREEMENT


         This SECURITY AGREEMENT, dated as of October 13, 2000, is made by
ZymeTx, Inc., a corporation organized under the laws of the State of Delaware,
with its principal offices located at 800 Research Parkway, Suite 100, Oklahoma
City, Oklahoma 73104, (the "Grantor") in favor of the investors identified on
Schedule A hereto (the "Lenders"), severally and not jointly.


                                   WITNESSETH:

         WHEREAS, the Grantor and Lenders have entered into a Purchase Agreement
dated [DATE] (as the same may be amended or modified from time to time, together
with all exhibits and schedules, the "Purchase Agreement") which provides for
Lenders to purchase 5% Senior Secured Convertible Debentures ("Debentures") of
the Grantor on the terms and conditions set forth therein; and

         WHEREAS, it is a requirement under the Purchase Agreement that the
Grantor shall have executed and delivered to the Lenders a security agreement
providing for the grant to Lenders of a security interest in all assets of the
Grantor.

         NOW, THEREFORE, in consideration of the mutual promises and covenants
contained herein and in order to induce the Lenders to purchase the Debentures
pursuant to the Purchase Agreement, the Grantor hereby agrees with the Lenders
as follows:


                             SECTION 1: DEFINITIONS

         1.1 DEFINITIONS. The following words shall have the following meanings
when used in this Security Agreement. All terms used herein not otherwise
defined in this Security Agreement shall have the meanings attributed to such
terms in the Purchase Agreement, and if not defined in the Purchase Agreement,
then the New York Uniform Commercial Code, as may be amended from time to time.
All references to dollar amounts shall mean amounts in lawful money of the
United States of America.

         "Account Grantor" means any person who is or who may become obligated
under, with respect to, or on account of an Account.

         "Accounts" means all presently existing and hereafter arising accounts,
contract rights (including under licenses), and all other forms of obligations
owing to the Grantor or any subsidiaries or joint ventures thereof arising out
of the sale or lease of goods or the rendition of services by such persons, or
arising out of the sale or lease of goods or the rendition of services by a
person other than such persons and acquired by such persons from such person by
assignment or purchase, including, without limitation, rights to payment with
respect to accounts of the direct or indirect subsidiaries of the Grantor that
are sold or assigned to the Grantor,




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irrespective of whether earned by performance, and any and all credit insurance,
guaranties, or security therefor.

         "Collateral" means each of the following: all assets of the Grantor or
any of its subsidiaries, including, without limitation, the Equipment; General
Intangibles; the Intellectual Property Collateral; the Accounts; the Inventory;
and the proceeds and products, whether tangible or intangible, of any of the
foregoing including proceeds of insurance covering any or all of the Collateral,
and any and all tangible or intangible, real or personal, property resulting
from the sale, exchange, collection, or other disposition of the Collateral, or
any portion thereof or interest therein, and the proceeds of any and all of the
foregoing.

         "Event of Default" means and includes any of the Events of Default set
forth in Section 3.1.

         "Equipment" means all machinery, equipment, office machinery,
furniture, fixtures, conveyors, tools, materials, storage and handling
equipment, computer equipment and hardware including central processing units,
terminals, drives, memory units, printers, keyboards, screens, peripherals and
input or output devices, automotive equipment, trucks, molds dies, stamps, motor
vehicles and other equipment of every kind and nature and wherever situated now
or hereafter directly or indirectly owned by the Grantor or its subsidiaries or
in which the Grantor or its subsidiaries may have any interest together with all
additions and accessions thereto, all replacements and all accessories and parts
therefor, all manuals, blueprints, know-how, warranties and records in
connection therewith, all rights against suppliers, warrantors, manufacturers,
sellers or others in connection therewith, and together with all substitutions
for any of the foregoing.

         "General Intangibles" shall mean all "General Intangibles," as such
term is defined in Section 9-106 of the Uniform Commercial Code of the State of
New York, now or hereafter directly or indirectly owned by the Grantor or its
subsidiaries, including, without limitation, Intellectual Property Collateral
and, to the extent, if any, not included therein, present and future trade
secrets and other proprietary information; trademarks, trade names and trademark
applications, service marks, business names, logos and the goodwill of the
business relating thereto; copyrights and copyright applications and all
tangible property embodying the copyrights; unpatented inventions (whether or
not patentable); designs; research and development results; patent applications
and patents; customer contracts; license agreements related to any of the
foregoing and the income therefrom; books, records, computer tapes or disks,
flow diagrams, specification sheets, source codes, object codes, and other
physical manifestations of the foregoing.

         "Indebtedness" means all amounts due and owing to the Lenders pursuant
to Debentures or the other Transaction Documents, together with all reasonable
expenses and disbursements relating to enforcement thereof, including, without
limitation, reasonable legal fees and disbursements.

         "Intellectual Property Collateral" means the following, existing
anywhere throughout the world:



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         All United States, international and foreign patents, patent
applications and statutory invention registrations, including, without
limitation, the patents and patent applications set forth in Schedule __ hereto
(as such Schedule __ may be supplemented from time to time by supplements to
this Agreement), together with all reissues, divisions, continuations,
continuations-in-part, extensions and reexaminations thereof, all inventions
therein, all rights therein provided by international treaties or conventions
and all improvements thereto, and all other rights of any kind whatsoever of the
Grantor accruing thereunder or pertaining thereto (the "Patents");

         All United States, international and foreign trademarks (including,
without limitation, service marks), certification marks, collective marks, trade
dress, logos, domain names, product configurations, trade names, business names,
corporate names and other source identifiers, whether or not registered, whether
currently in use or not, including, without limitation, all common law rights
and registrations and applications for registration thereof, including, without
limitation, the trademark registrations and trademark applications set forth in
Schedule C hereto (as such Schedule C may be supplemented from time to time by
supplements to this Agreement) and all other marks registered in the U.S. Patent
and Trademark Office or in any office or agency of any State or Territory of the
United States or any foreign jurisdiction, and all rights therein provided by
international treaties or conventions, all reissues, extensions and renewals of
any of the foregoing, together in each case with the goodwill of the business
connected therewith and symbolized thereby, and all rights corresponding thereto
throughout the world and all other rights of any kind whatsoever of the Grantor
accruing thereunder or pertaining thereto (the "Trademarks");

         All United States, international and foreign copyrights, copyright
applications, copyright registrations and like protections in each work of
authorship, whether statutory or common law, whether published or unpublished,
any renewals or extensions thereof, all copyrights of works based on,
incorporated in, derived from, or relating to works covered by such copyrights,
including, without limitation, the copyright registrations and copyright
applications set forth in Schedule C hereto (as such Schedule C may be
supplemented from time to time, together with all rights corresponding thereto
throughout the world and all other rights of any kind whatsoever of the Grantor
accruing thereunder or pertaining thereto (the "Copyrights");

         All United States, international and foreign confidential and
proprietary information, including, without limitation, know-how, trade secrets,
manufacturing and production processes and techniques, inventions, research and
development information, technical data, financial, marketing and business data,
pricing and cost information, business and marketing plans and customer and
supplier lists and information (the "Trade Secrets");

         All United States, international and foreign computer software programs
and databases (including, without limitation, source code, object code and all
related applications and data files), firmware, and documentation and materials
relating thereto, and all rights with respect to the foregoing, together with
any and all options, warranties, service contracts, program services, test
rights, maintenance rights, improvement rights, renewal rights and
indemnifications and any substitutions, replacements, additions or model
conversions of any of the foregoing (the "Computer Software ");




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         All United States, international and foreign license agreements,
permits, authorizations and franchises, whether with respect to the Patents,
Trademarks, Copyrights, Trade Secrets or Computer Software, or with respect to
the patents, trademarks, copyrights, trade secrets, computer software or other
proprietary right of any other Person, including, without limitation, the
license agreements set forth in Schedule C hereto (as such Schedule C may be
supplemented from time to time, and all income, royalties and other payments now
or hereafter due and/or payable with respect thereto (the "Licenses"); and

         Any and all claims for damages for past, present and future
infringement, misappropriation or breach with respect to the Patents,
Trademarks, Copyrights, Trade Secrets, Computer Software or Licenses, with the
right, but not the obligation, to sue for and collect, or otherwise recover,
such damages.

         "Inventory" means all present and future inventory in which the Grantor
or any subsidiaries or joint ventures thereof have any interest, including goods
(whether finished or unfinished) held for sale or lease or to be furnished under
a contract of service and all of such persons' present and future raw materials,
work in process, finished goods, and packing and shipping materials, wherever
located, and any documents of title representing any of the above.

         "Permitted Liens" means any purchase money security interest existing
on the date of this Agreement and securing the purchase of the Equipment.

         "Registration Rights Agreement" means the Registration Rights
Agreement, dated as of October 13, 2000 by and among the Grantor and the
Lenders.

         "Security Agreement" means this Security Agreement, as this Security
Agreement may be amended or modified from time to time, together with all
exhibits and schedules attached to this Security Agreement from time to time.

SECTION 2: GRANT OF SECURITY INTEREST; OBLIGATIONS OF THE GRANTOR

         2.1 GRANT OF SECURITY INTEREST. As collateral security for all of the
Indebtedness, the Grantor hereby grants to Lenders a continuing first priority
perfected security interest in all currently existing and hereafter acquired or
arising Collateral to secure prompt repayment of any and all Indebtedness and to
secure prompt performance by the Grantor of each of its covenants and duties
under the Debentures, and the other Transaction Documents. The Grantor further
agrees that Lenders shall have the rights stated in this Security Agreement with
respect to the Collateral in addition to all other rights which Lenders may have
by law, by contract or in equity.

         2.2 REPRESENTATIONS AND OBLIGATIONS OF THE GRANTOR. The Grantor
represents, warrants and covenants to Lenders as follows:

               (a)  Perfection of Security Interest. The Grantor agrees to
                    execute at any time and from time to time such financing
                    statements and to take whatever other actions are requested
                    by Lenders to perfect and continue Lenders' first priority



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                    security interest in the Collateral. Upon request of the
                    Lenders, the Grantor will deliver to the Lenders copies of
                    any and all documents evidencing or constituting the
                    Collateral and upon request of the Lenders following the
                    occurrence of an Event of Default (as defined in Section 3.1
                    hereof), such Grantor will deliver the originals of such
                    documents to the Lenders. Upon request of the Lenders, the
                    Grantor will note Lenders' interest, as the case may be,
                    upon any and all Accounts if not delivered to Lenders for
                    possession by Lenders. Lenders may at any time and from time
                    to time, and without further authorization from the Grantor,
                    file a carbon, photographic or other reproduction of any
                    financing statement or of this Security Agreement for use as
                    a financing statement. The Grantor will reimburse Lenders
                    for all reasonable expenses for the perfection and the
                    continuation of the perfection of Lenders' security interest
                    in the Collateral, including reasonable attorneys fees. The
                    Grantor will promptly notify Lenders of any change in its
                    name including any change to the assumed business names of
                    the Grantor. This is a continuing Security Agreement and
                    will continue in effect until all of the Indebtedness is
                    paid in full and Lenders shall release their interest in the
                    Collateral upon the full and final payment and satisfaction
                    of the Indebtedness. If payment is made by the Grantor,
                    whether voluntarily or otherwise, or by any third party, on
                    the Indebtedness and thereafter Lenders are forced to remit
                    the amount of that payment to the Grantor's trustee in
                    bankruptcy or to any similar person under any federal, state
                    or foreign bankruptcy law or other law for the relief of
                    Grantor, the Indebtedness shall be considered unpaid for the
                    purpose of enforcement of this Security Agreement.

               (b)  Ownership. The Grantor is the legal and beneficial owner of
                    the Collateral free and clear of any Lien, claim, option or
                    right of others, except for the security interest created
                    under this Agreement. No effective financing statement or
                    other instrument similar in effect covering all or any part
                    of the Collateral or listing the Grantor or any trade name
                    of the Grantor as debtor is on file in any recording office.

               (c)  Necessary Actions. All filings and other actions necessary
                    or desirable to perfect and protect the security interest in
                    the Collateral of the Grantor created under this Agreement
                    have been duly made or taken and are in full force and
                    effect or will be taken within five (5) business days after
                    Closing, and this Agreement creates in favor of the Lenders
                    a valid and, together with such filings and other actions,
                    perfected first priority security interest in the Collateral
                    of the Grantor, securing the payment of the Indebtedness.

               (d)  All Collateral. The Intellectual Property Collateral set
                    forth on Schedule __ hereto includes all of the Patents,
                    Trademarks, Copyrights, and Licenses owned by the Grantor as
                    of the Effective Date.

               (e)  Filings. The Grantor has made or performed or, after the
                    Effective Date, will perform all filings, recordings and
                    other acts and has paid all required fees and taxes to
                    maintain and protect its interest in each and every item of
                    Intellectual



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                    Property Collateral listed on Schedule __ in full force and
                    effect, and to protect and maintain its interest therein
                    including, without limitation, recordations of any of its
                    interests in the Patents and Trademarks with the U.S. Patent
                    and Trademark Office and in corresponding national and
                    international offices, and recordation of any of its
                    interests in the Copyrights with the U.S. Copyright Office
                    and in corresponding national and international offices. The
                    Grantor has used proper statutory notice in connection with
                    its use of each Patent, Trademark and Copyright.

               (f)  Trade Secrets. To the best of the Grantor's acknowledge, (A)
                    none of the Trade Secrets of the Grantor has been used,
                    divulged, disclosed or appropriated to the detriment of the
                    Grantor for the benefit of any other Person other than the
                    Grantor; (B) no employee, independent contractor or agent of
                    the Grantor has misappropriated any trade secrets of any
                    other Person in the course of the performance of his or her
                    duties as an employee, independent contractor or agent of
                    the Grantor; and (C) no employee, independent contractor or
                    agent of the Grantor is in default or breach of any term of
                    any employment agreement, non-disclosure agreement,
                    assignment of inventions agreement or similar agreement or
                    contract relating in any way to the protection, ownership,
                    development, use or transfer of the Grantor's Intellectual
                    Property Collateral.

               (g)  Further Assurances. The Grantor agrees that from time to
                    time, at the expense of the Grantor, the Grantor will
                    promptly execute and deliver all further instruments and
                    documents, and take all further action, that may be
                    necessary or desirable, or that the Lenders may reasonably
                    request, in order to perfect and protect any pledge,
                    assignment or security interest granted or purported to be
                    granted by the Grantor hereunder or to enable the Lenders to
                    exercise and enforce its rights and remedies hereunder with
                    respect to any Collateral of the Grantor. Without limiting
                    the generality of the foregoing, the Grantor will promptly
                    with respect to Collateral of the Grantor: (i) if any
                    Collateral shall be evidenced by a promissory note or other
                    instrument or chattel paper, deliver and pledge to the
                    Lenders hereunder such note or instrument or chattel paper
                    duly endorsed and accompanied by duly executed instruments
                    of transfer or assignment, all in form and substance
                    reasonably satisfactory to the Lenders; (ii) execute and
                    file such financing or continuation statements, or
                    amendments thereto, and such other instruments or notices,
                    as may be necessary or desirable, or as the Lenders may
                    reasonably request, in order to perfect and preserve the
                    security interest granted or purported to be granted by the
                    Grantor hereunder; and (iii) deliver to the Lenders evidence
                    that all other action that the Lenders may deem reasonably
                    necessary or desirable in order to perfect and protect the
                    security interest created by the Grantor under this
                    Agreement has been taken. The Grantor hereby authorizes the
                    Lenders to file one or more financing or continuation
                    statements, and amendments thereto, relating to all or any
                    part of the Collateral of the Grantor without the signature
                    of the Grantor where permitted by law. A photocopy or other
                    reproduction of this Agreement or any financing statement
                    covering the





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                    Collateral or any part thereof shall be sufficient as a
                    financing statement where permitted by law.

               (h)  Intellectual Property Collateral. With respect to each item
                    of its Intellectual Property Collateral listed on Schedule
                    C, the Grantor, in accordance with its reasonable business
                    judgment, agrees to take, at its expense, all necessary
                    steps, including, without limitation, in the U.S. Patent and
                    Trademark Office, the U.S. Copyright Office and any other
                    governmental authority, to (i) maintain the validity and
                    enforceability of each such item of Intellectual Property
                    Collateral and maintain each such item of Intellectual
                    Property Collateral in full force and effect, and (ii)
                    pursue the registration and maintenance of each patent,
                    trademark, or copyright registration or application, now or
                    hereafter included in the Intellectual Property Collateral
                    of the Grantor, including, without limitation, the payment
                    of required fees and taxes, the filing of responses to
                    office actions issued by the U.S. Patent and Trademark
                    Office, the U.S. Copyright Office or other governmental
                    authorities, the filing of applications for renewal or
                    extension, the filing of affidavits under Sections 8 and 15
                    of the U.S. Trademark Act, the filing of divisional,
                    continuation, continuation-in-part, reissue and renewal
                    applications or extensions, the payment of maintenance fees
                    and the participation in interference, reexamination,
                    opposition, cancellation, infringement and misappropriation
                    proceedings. No Grantor shall, without the written consent
                    of the Lenders, discontinue use of or otherwise abandon any
                    Intellectual Property Collateral, or abandon any right to
                    file an application for letters patent, trademark, or
                    copyright.

               (i)  Certain Notices. The Grantor agrees to notify the Lender
                    within five (5) business days if the Grantor learns (i) that
                    any item of the Intellectual Property Collateral may have
                    become abandoned, placed in the public domain, invalid or
                    unenforceable, or of any adverse determination or
                    development regarding the Grantor's ownership of any of the
                    Intellectual Property Collateral or its right to register
                    the same or to keep and maintain and enforce the same, or
                    (ii) of any adverse determination or the institution of any
                    proceeding (including, without limitation, the institution
                    of any proceeding in the U.S. Patent and Trademark Office or
                    any court) regarding any item of the Intellectual Property
                    Collateral. In the event that any Grantor becomes aware that
                    any item of the Intellectual Property Collateral material to
                    the business of any Grantor is being infringed or
                    misappropriated by a third party, the Grantor shall promptly
                    notify the Lawyers and shall take such actions, at its
                    expense, as are reasonable and appropriate under the
                    circumstances to protect such Intellectual Property
                    Collateral, including, without limitation, suing for
                    infringement or misappropriation and for an injunction
                    against such infringement or misappropriation.

               (j)  Certain Steps. The Grantor shall take all steps which are
                    reasonable and appropriate under the circumstances to
                    preserve and protect each item of its Intellectual Property
                    Collateral material to its business, including, without





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                    limitation, maintaining the quality of any and all products
                    or services used or provided in connection with any of the
                    Trademarks, consistent with the quality of the products and
                    services as of the date hereof, and taking all steps
                    necessary to ensure that all licensed users of any of the
                    Trademarks use such consistent standards of quality.

               (k)  After Acquired Property. The Grantor agrees that, should it
                    obtain an ownership interest in any item of the type which
                    would be considered Collateral (the "After-Acquired
                    Property"), (i) the provisions of Section __ shall
                    automatically apply thereto, (ii) any such After-Acquired
                    Property and, in the case of trademarks, the goodwill of the
                    business connected therewith or symbolized thereby, shall
                    automatically become part of the Collateral subject to the
                    terms and conditions of this Agreement with respect thereto,
                    (iii) the Grantor shall give prompt written notice thereof
                    to the Lenders in accordance herewith and (iv) the Grantor
                    shall execute and deliver to the Lenders a Security
                    Agreement Supplement in a form requested by the Lenders
                    covering such After-Acquired Property as "Additional
                    Collateral" thereunder and as defined therein, and, as is
                    necessary shall record such Security Agreement Supplement
                    with the U.S. Patent and Trademark Office, the U.S.
                    Copyright Office and any other governmental authorities as
                    is necessary or desirable to perfect the security interest
                    hereunder in such After-Acquired Property.


               (l)  Power of Attorney. The Grantor hereby irrevocably makes,
                    constitutes, and appoints each Lender (and all of such
                    Lender's general partners, officers, employees, or agents
                    designated by such Lender) as its true and lawful attorney,
                    with power to: (i) sign the Grantor's name on any of the
                    documents described hereunder or on any other similar
                    documents to be executed, recorded, or filed in order to
                    perfect or continue perfected Lenders' security interest in
                    the Collateral; (ii) at any time that an Event of Default
                    has occurred and is continuing, execute, sign and endorse
                    the Grantor's name on any invoice or bill of lading relating
                    to any Account, drafts against Account Debtors, schedules
                    and assignments of Accounts, verifications of Accounts, and
                    notices to Account Debtor; (iii) send requests for
                    verification of Accounts; (iv) at any time that an Event of
                    Default has occurred and is continuing, execute, sign and
                    endorse the Grantor's name on any checks, notices,
                    instruments, acceptances, money orders, drafts, warrants or
                    other item of payment or security that may come into
                    Lenders' possession; (v) at any time that an Event of
                    Default has occurred and is continuing, demand, collect,
                    receive, receipt for, sue and recover all sums of money or
                    other property which may now or hereafter become due, owing
                    or payable from the Collateral; (vi) file any claim or
                    claims or, following an Event of Default, take any action or
                    institute or take part in any proceedings, either in its own
                    name or in the name of the Grantor, or otherwise, which in
                    the discretion of Lenders may seem to be necessary or
                    advisable; (vii) at any time that an Event of Default has
                    occurred and following acceleration of the Indebtedness,
                    direct the Account Grantor and other persons sending mail to
                    the Grantor to send all



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                    mail relating to the Collateral to the Lenders; (viii) at
                    any time that an Event of Default has occurred and is
                    continuing, make, settle, and adjust all claims under the
                    Grantor' policies of insurance and make all determinations
                    and decisions with respect to such policies of insurance;
                    and (ix) at any time that an Event of Default has occurred
                    and following acceleration of the Indebtedness, settle and
                    adjust disputes and claims respecting the Accounts directly
                    with Account Grantor, for amounts and upon terms which
                    Lenders determine to be reasonable, and Lenders may cause to
                    be executed and delivered any documents and releases which
                    Lenders determine to be necessary. The appointment of
                    Lenders as the Grantor's attorneys, and each and every one
                    of Lenders' rights and powers, being coupled with an
                    interest, is irrevocable and shall remain in full force and
                    effect until all of the Indebtedness has been fully repaid
                    and performed.

               (m)  No Violation. The execution and delivery of this Security
                    Agreement does not violate any law or agreement governing
                    the Grantor or to which the Grantor is a party, and the
                    Grantor' certificate or articles of incorporation and bylaws
                    or other constating documents do not prohibit any term or
                    condition of this Security Agreement. The execution and
                    delivery hereof is in the interest of the Grantor.

               (n)  Enforceability of Collateral. With respect to the Accounts,
                    the Collateral is enforceable in accordance with its terms,
                    is genuine, and complies in all material respects with
                    applicable laws concerning form, content and manner of
                    preparation and execution, and, to the best the knowledge of
                    the Grantor, all persons appearing to be obligated on the
                    Collateral have authority and capacity to contract and are
                    in fact obligated as they appear to be on the Collateral.

               (o)  Accounts. All Accounts existing as of the date hereof are
                    good and valid Accounts representing an undisputed, bona
                    fide indebtedness incurred by the Account Debtors, and there
                    exists no set-offs or counterclaims against any such
                    Accounts and no agreements under which any deductions or
                    discounts may be claimed with any Account Debtor except as
                    disclosed to Lenders in writing.

               (p)  Removal of Collateral; Transactions Involving Collateral. To
                    the extent the Collateral consists of Accounts, the records
                    and other documents pertaining to the Collateral shall be
                    kept at the offices of the Grantor at the address specified
                    in the preamble, or at such other locations as are
                    reasonably acceptable to Lenders. Except for transactions in
                    the ordinary course of business in accordance with past
                    practice or for sales or dispositions on arm's length terms
                    and for fair equivalent value, the Grantor shall not sell,
                    offer to sell, or otherwise transfer, dispose of or encumber
                    the Collateral. The Grantor shall not pledge, mortgage,
                    encumber or otherwise permit the Collateral to be subject to
                    any lien, security interest, encumbrance, or charge, other
                    than the security interest provided for in this Security
                    Agreement and Permitted Liens,





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                    without the prior written consent of Lenders which may be
                    withheld for any reason in Lenders' sole discretion.

               (q)  Title. The Grantor represents and warrants to Lenders that
                    as of the date hereof, the Grantor holds good and marketable
                    title to the Collateral, free and clear of all liens and
                    encumbrances except for the lien of this Security Agreement
                    and Permitted Liens. No financing statement or other
                    evidence of a lien or transfer covering any of the
                    Collateral is on file in any public office in any
                    jurisdiction other than those which reflect the security
                    interest created by this Security Agreement or Permitted
                    Liens. The Grantor shall defend Lenders' rights in the
                    Collateral against any and all claims and demands.

               (r)  Prepayments. The Grantor represents and warrants to Lenders
                    that none of the Collateral has been prepaid by any Account
                    Debtor for any Accounts.

               (s)  Collateral Schedules and Locations. Upon Lenders' request,
                    on a monthly basis, the Grantor shall deliver to Lenders
                    schedules of the Collateral, including such information as
                    Lenders may require, including without limitation names and
                    addresses of Account Debtors and agings of Accounts,
                    including without limitation the location of mobile goods or
                    changes in any certificates of title, and identification of
                    Intellectual Property Collateral, including but not limited
                    to name or title, application and registration number, and
                    the jurisdiction in which such collateral is located or
                    filed. The Grantor represents and warrants to Lenders that a
                    detailed list of the Collateral existing as of the date
                    hereof is set forth on Schedule B attached hereto, and such
                    Schedule B (x) is true, accurate and complete in all
                    material respects, (y) identifies those items of Collateral
                    which contain a certificate of title along with the
                    jurisdiction of such certificates, and (z) those items of
                    Collateral which are mobile goods along with the present
                    location of such goods. Schedule B shall be updated monthly
                    by the Grantor to reflect any changes thereto. (t)
                    Application of Payments Received With Respect to Collateral.
                    Any amounts received by or on behalf of the Grantor with
                    respect to any Account pledged as Collateral hereunder shall
                    be applied in accordance with the Debentures.

               (u)  Possession and Collection of Accounts. Following an Event of
                    Default and following acceleration of the Indebtedness, the
                    records and documents evidencing the Accounts pledged as
                    Collateral hereunder shall, upon Lenders' request, be
                    delivered to Lenders or their agent and held in accordance
                    with the terms of this Security Agreement.

               (v)  Maintenance and Inspection of Collateral. The Grantor shall
                    maintain or cause to be maintained all tangible Collateral
                    in good condition and repair except for ordinary wear and
                    tear. The Grantor will not commit or permit material damage
                    to or destruction of the Collateral or any material part of
                    the Collateral. Lenders and their designated representatives
                    and agents shall have





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                    the right at all reasonable times, upon reasonable advance
                    notice, to examine, inspect, and audit the Collateral
                    wherever located and the books, records or any property
                    which is otherwise used in connection with the Collateral.
                    The Grantor shall immediately notify Lenders of all material
                    cases involving the return, rejection, repossession, loss or
                    damage of or to any Collateral; of any request for credit or
                    adjustment or of any other dispute arising with respect to
                    the Collateral; and generally of all happenings and events
                    materially adversely affecting the Collateral or the value
                    or the amount of the Collateral.

               (w)  Taxes, Assessments and Liens. The Grantor will pay when due
                    all taxes, assessments and liens upon the Collateral, its
                    use or operation, upon this Security Agreement. The Grantor
                    may withhold any such payment or may elect to contest any
                    lien if the Grantor is in good faith conducting an
                    appropriate proceeding to contest the obligation to pay and
                    so long as Lenders' interest in the Collateral is not
                    jeopardized in Lenders' sole opinion. If any of the
                    Collateral is subjected to a lien which is not discharged
                    within thirty (30) days, the Grantor shall deposit with
                    Lenders cash, a sufficient corporate surety bond or other
                    security satisfactory to Lenders (in their discretion) in an
                    amount adequate to provide for the discharge of the lien
                    plus any interest, reasonable costs, attorneys' fees or
                    other charges that could accrue as a result of foreclosure
                    or sale of the Collateral. In any contest the Grantor shall
                    defend themselves and Lenders and shall satisfy any final
                    adverse judgment before enforcement against the Collateral.
                    The Grantor shall name Lenders as an additional obligee
                    under any surety bond furnished in such contest proceedings.

               (x)  Incorporation by Reference. The Grantor hereby restates and
                    affirms all representations, warranties and agreements
                    contained in the Purchase Agreement, the terms and
                    conditions of which are hereby incorporated herein by
                    reference.

               (y)  Compliance With Governmental Requirements. The Grantor shall
                    comply promptly with all laws, ordinances and regulations of
                    all governmental authorities applicable to the production,
                    disposition, or use of the Collateral, non-compliance with
                    which would have a material adverse effect on the Collateral
                    or the business of the Grantor. The Grantor may contest in
                    good faith any such law, ordinance or regulation and
                    withhold compliance during any proceeding, including
                    appropriate appeals, so long as Lenders' interest in the
                    Collateral, in Lenders' sole opinion, is not jeopardized.

               (z)  Insurance. The Grantor shall comply with all insurance
                    requirements and provisions set forth in the Purchase
                    Agreement.

               (aa) The Grantor's Right to Possession and to Collect Accounts.
                    Until the occurrence of an Event of Default and acceleration
                    of Indebtedness and except as otherwise provided herein with
                    respect to the Accounts, the Grantor may have possession of
                    the tangible personal property and beneficial use of all the




                                       11
<PAGE>   12


                    Collateral and may use it in any lawful manner not
                    inconsistent with this Security Agreement or the Transaction
                    Documents, provided that the Grantor's right to possession
                    and beneficial use shall not apply to any Collateral where
                    possession of the Collateral by Lenders is required by law
                    to perfect Lenders' security interest in such Collateral. At
                    any time an Event of Default and following acceleration of
                    Indebtedness, Lenders may exercise their right to directly
                    collect the Accounts and to notify Account Debtors to make
                    payments directly to Lenders for application to the
                    Indebtedness, and the Grantor authorize and directs the
                    Account Debtors, if Lenders exercise such right, to make
                    payments on the Accounts to Lenders. If Lenders at any time
                    have possession of any Collateral, whether before or after
                    an Event of Default, Lenders shall be deemed to have
                    exercised reasonable care in the custody and preservation of
                    the Collateral if Lenders take such action for that purpose
                    as the Grantor shall reasonably request or as Lenders, in
                    Lenders' sole reasonable discretion, shall deem appropriate
                    under the circumstances, but failure to honor any request by
                    the Grantor shall not of itself be deemed to be a failure to
                    exercise reasonable care. Lenders shall not be required to
                    take any steps necessary to preserve any rights in the
                    Collateral against prior parties, nor to protect, preserve
                    or maintain any security interest given to secure the
                    Collateral. Lenders shall have the right to direct who shall
                    collect and service the Accounts.

               (bb) Transactions with Others. Lenders may (i) extend time for
                    payment or other performance, (ii) grant a renewal or change
                    in terms or conditions, or (iii) compromise, compound or
                    release any obligation, with the Grantor, endorsers or any
                    guarantor of the Indebtedness as Lenders deem advisable,
                    without obtaining the prior written consent of the Grantor,
                    and no such act or failure to act shall affect Lenders'
                    rights against the Grantor or the Collateral.

               (cc) Expenditures by Lenders. If not discharged or paid when due,
                    and provided that such items have not been contested as
                    permitted herein Lenders may (but shall not be obligated to)
                    discharge or pay any amounts required to be discharged or
                    paid by the Grantor under this Security Agreement, including
                    without limitation all taxes, liens, security interests,
                    encumbrances, and other claims, at any time levied or placed
                    on the Collateral. Lenders also may (but shall not be
                    obligated to) pay all reasonable costs for insuring,
                    maintaining and preserving the Collateral. All such
                    expenditures incurred or paid by Lenders for such purposes
                    will then bear interest at the then rate charged under the
                    Debentures from the date incurred or paid by Lenders to the
                    date of repayment by the Grantor. All such expenses shall
                    become a part of the Indebtedness and, at Lenders' option,
                    will (i) be payable on demand or (ii) be added to the
                    balance of the Debentures, becoming a part of the
                    outstanding principal amount due and payable on the
                    applicable Interest Payment Dates (as defined in the
                    Debentures). This Security Agreement also will secure
                    payment of these amounts. Such right under this subsection
                    shall be in addition to all other rights and remedies to
                    which Lenders may be entitled upon the occurrence of an
                    Event of Default.




                                       12
<PAGE>   13


               (dd) Sale or Factoring of Accounts; Release of Accounts. Except
                    with respect to Permitted Liens, the Grantor shall not sell
                    or otherwise transfer or encumber any of the Accounts
                    without Lenders' written consent. It is expressly agreed
                    that Lenders are under no obligation to grant such a consent
                    and will do so only in its sole and absolute discretion on
                    terms and conditions they deem acceptable in their sole and
                    absolute discretion.

               (ee) Location. The Grantor represents and warrants that all of
                    the Collateral is located in the United States.

               (ff) In the event that in the future, any Accounts or Inventory
                    are held by Subsidiaries, affiliates or joint ventures of
                    the Grantor other than the Grantor, then the Grantor shall
                    cause such entities to grant the Lenders an exclusive first
                    priority lien in such Accounts and Inventory, to cause such
                    entities to enter into security agreements reasonably
                    satisfactory to Lenders, and to take all actions necessary
                    to perfect such security interests.

         2.3 NON-PUBLIC INFORMATION. Notwithstanding any other provision of this
Agreement, the Grantor shall be under no obligation to provide, and shall not
provide, material non-public information to the Lenders without the prior
written consent of those Lenders.

SECTION 3: EVENTS OF DEFAULT; REMEDIES

         3.1 EVENTS OF DEFAULT. Each of the following shall constitute an Event
of Default under this Security Agreement:

               (a)  Event of Default under Transaction Documents. The occurrence
                    of an Event of Default under the Transaction Documents.

               (b)  Other Defaults. Failure of the Grantor to comply with or to
                    perform when due or required (after any applicable cure
                    period) any term, obligation, covenant or condition
                    contained in the Transaction Documents or in any other
                    agreement or instruments between Lenders and the Grantor.

               (c)  False Statements. Any warranty, representation or statement
                    made or furnished to Lenders by the Grantor under the
                    Transaction Documents is false or misleading in any material
                    respect, either now or at the time made or furnished.

               (d)  Defective Collateralization. As a result of any act or
                    failure to act by the Grantor, the Transaction Documents
                    cease to be in full force and effect (including failure of
                    the Grantor to create a valid and perfected security
                    interest or lien as intended) at any time and for any
                    reason, or if any of the Collateral is materially impaired.

               (e)  Insolvency. The dissolution or termination of Grantor's
                    existence as a going business, the insolvency of Grantor,
                    the appointment of a receiver for any part of Grantor's
                    property, any assignment for the benefit of creditors, or
                    the





                                       13
<PAGE>   14


                    commencement of any insolvency proceeding by or against the
                    Grantor, which proceeding shall not have been dismissed
                    within forty-five (45) days thereafter.

               (f)  Creditor Proceedings. Commencement of foreclosure, whether
                    by judicial proceeding, self-help, repossession or any other
                    method, by any creditor of the Grantor (with respect to
                    indebtedness equal to or in excess of $25,000) against the
                    Collateral or any other collateral securing the
                    Indebtedness. This includes a garnishment of any of any
                    Grantor's accounts, including without limitation deposit
                    accounts. However, this Event of Default shall not apply if
                    there is a good faith dispute by the Grantor as to the
                    validity or reasonableness of the claim which is the basis
                    of the creditor proceeding and if the Grantor gives Lenders
                    written notice of the creditor proceeding and deposits with
                    Lenders monies or a surety bond for the creditor proceeding,
                    in an amount determined by Lenders, in their sole
                    discretion, as being an adequate reserve or bond for the
                    dispute.

         3.2 RIGHTS AND REMEDIES ON DEFAULT. If an Event of Default occurs and
is continuing under this Security Agreement, at any time thereafter, Lenders
shall have all the rights of a secured party under the New York Uniform
Commercial Code. In addition and without limitation, Lenders may exercise any
one or more of the following rights and remedies:

               (a)  Accelerate Indebtedness. Lenders may declare the entire
                    Indebtedness immediately due and payable, upon three
                    business days' notice, if prior notice with respect to the
                    Event of Default shall not have been previously given.

               (b)  Assemble Collateral. Lenders may require the Grantor to
                    deliver to Lenders all or any portion of the Collateral and
                    other documents relating to the Collateral. Lenders may
                    require the Grantor to assemble the Collateral and make it
                    available to Lenders at a place to be designated by Lenders.
                    Lenders also shall have full power to enter upon the
                    property of the Grantor to take possession of and remove the
                    Collateral.

               (c)  Sell the Collateral. Lenders shall have full power to sell,
                    lease, transfer, or otherwise deal with the Collateral or
                    proceeds thereof in its own name or that of the Grantor.
                    Lenders may sell the Collateral at public auction or private
                    sale. Unless the Collateral threatens to decline speedily in
                    value or is of a type customarily sold on a recognized
                    market, Lenders will give the Grantor reasonable notice of
                    the time after which any private sale or any other intended
                    disposition of the Collateral is to be made. The
                    requirements of reasonable notice shall be met if such
                    notice is given at least ten (10) days before the time of
                    the sale or disposition. All expenses relating to the
                    disposition of the Collateral, including without limitation
                    the expenses of retaking, holding, insuring, preparing for
                    sale and selling the Collateral, shall become a part of the
                    Indebtedness secured by this Security Agreement and shall be
                    payable on demand, with interest at the lower of six percent
                    (6%) per annum above Citibank's (or any successor's price
                    rate) or the highest rate




                                       14
<PAGE>   15


                    permitted by law from date of expenditure until repaid.

               (d)  Foreclosure. Maintain a judicial suit for foreclosure and
                    sale of the Collateral.

               (e)  Appoint Receiver. To the extent permitted by applicable law,
                    Lenders shall have the following rights and remedies
                    regarding the appointment of a receiver: (i) Lenders may
                    have a receiver appointed as a matter of right, and (ii) all
                    reasonable fees of the receiver and the receiver's attorney
                    shall become part of the Indebtedness secured by this
                    Security Agreement and shall be payable on demand, with
                    interest at the lower of six percent (6%) per annum above
                    Citibank's (or any successor's) prime rate or the highest
                    rate permitted by law from date of expenditure until repaid.

               (f)  Transfer Title. Effect transfer of title upon sale of all or
                    part of the Collateral. For this purpose, the Grantor
                    irrevocably appoints Lenders, acting singly, as its
                    attorneys-in-fact to execute endorsements, assignments and
                    instruments in the name of the Grantor as shall be necessary
                    or reasonable.

               (g)  Collect Revenues, Apply Accounts. Lenders, either themselves
                    or through a receiver, may collect the payments, rents,
                    income, and revenues from the Collateral. Lenders may at any
                    time in their discretion transfer any Collateral into their
                    own names or that of their nominees and receive the
                    payments, rents, income, and revenues therefrom and hold the
                    same as security for the Indebtedness or apply it to payment
                    of the Indebtedness in such order of preference as Lenders
                    may determine. Lenders may demand, collect, receipt for,
                    settle, compromise, adjust, sue for, foreclose, or realize
                    on the Collateral as Lenders may determine, whether or not
                    the Indebtedness is then due. For these purposes, Lenders
                    may, on behalf of and in the name of the Grantor, following
                    an Event of Default and acceleration of Indebtedness, direct
                    Account Debtor and other parties sending mail relating to
                    the Collateral to Grantor, to send such mail directly to the
                    Lenders; and endorse Debentures, checks, drafts, money
                    orders, documents of title, instruments and items pertaining
                    to payment, shipment, or storage of any Collateral. To
                    facilitate collection, Lenders may, following an Event
                    Default, notify Account Debtor and obligors on any
                    Collateral to make payments directly to Lenders.

               (h)  Obtain Deficiency. If Lenders choose to sell any or all of
                    the Collateral and/or pursue any other remedy available
                    hereunder, under any other agreement, at law or in equity,
                    Lenders may obtain a judgment against the Grantor for any
                    deficiency remaining on the Indebtedness due to Lenders
                    after application of all amounts received from the exercise
                    of the rights provided in this Security Agreement. The
                    Grantor shall be liable for a deficiency even if the
                    transaction described in this Subsection is a sale of
                    accounts or chattel paper.

               (i)  Application of Proceeds. The proceeds of any foreclosure or
                    realization upon the Collateral shall be applied:



                                       15
<PAGE>   16


                    (A)  First, to the reasonable costs and expenses of
                         collection;

                    (B)  Second, to overdue interest and fees;

                    (C)  Third, to the outstanding principal amount of the
                         Indebtedness; and

                    (D)  Fourth, any excess to the Grantor or other party or
                         parties in accordance with applicable law or court
                         order.

               (j)  Other Rights and Remedies. Lenders shall have and may
                    exercise any or all rights and remedies they may have
                    available at law, in equity, or otherwise.

         3.3 CUMULATIVE REMEDIES. All of Lenders' rights and remedies, whether
evidenced by this Security Agreement the other Transaction Documents by any
other writing, shall be cumulative and may be exercised singularly or
concurrently. Election by Lenders to pursue any remedy shall not exclude pursuit
of any other remedy, and an election to make expenditures or to take action to
perform an obligation of the Grantor under this Security Agreement, after the
Grantor's failure to perform, shall not affect Lenders' right to declare a
default and to exercise their remedies. The Lenders shall not be required to
proceed against or exercise its remedies with respect to any Collateral prior to
or in lieu of pursuing any other remedy.

SECTION 4: MISCELLANEOUS PROVISIONS

         4.1 ENTIRE AGREEMENT; AMENDMENTS. This Security Agreement, together
with the other Transaction Documents, constitutes the entire understanding and
agreement of the parties as to the matters set forth in this Security Agreement.
No alteration of or amendment to this Security Agreement shall be effective
unless given in writing and signed by the party or parties sought to be charged
or bound by the alteration or amendment.

         4.2 CHOICE OF LAW AND VENUE; JURY TRIAL WAIVER. THE VALIDITY OF THIS
SECURITY AGREEMENT, ITS CONSTRUCTION, INTERPRETATION, AND ENFORCEMENT, AND THE
RIGHTS OF THE PARTIES HERETO SHALL BE DETERMINED UNDER, GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF NEW YORK. THE
PARTIES IRREVOCABLY AND UNCONDITIONALLY AGREE (1) THAT ALL ACTIONS OR
PROCEEDINGS ARISING IN CONNECTION WITH THIS SECURITY AGREEMENT SHALL BE TRIED
AND LITIGATED ONLY IN THE STATE AND FEDERAL COURTS LOCATED IN THE STATE OF NEW
YORK, COUNTY OF NEW YORK AND THAT THE PARTIES SHALL BE SUBJECT TO THE
JURISDICTION OF SUCH COURTS, AND ONLY SUCH COURTS AND (2) THAT SERVICE OF
PROCESS BY CERTIFIED MAIL, RETURN RECEIPT REQUESTED (AND SERVICE SO MADE SHALL
BE DEEMED COMPLETE FIVE DAYS AFTER THE SAME HAS BEEN POSTED AS AFORESAID) OR BY
PERSONAL SERVICE SHALL BE DEEMED IN EVERY RESPECT EFFECTIVE SERVICE UPON SUCH
PARTY IN ANY SUCH SUIT OR PROCEEDING. EACH PARTY WAIVES, TO THE EXTENT PERMITTED
UNDER APPLICABLE LAW, ANY RIGHT EACH MAY HAVE TO ASSERT THE DOCTRINE OF FORUM
NON CONVENIENS OR TO OBJECT TO VENUE TO THE EXTENT ANY PROCEEDING IS BROUGHT IN
ACCORDANCE WITH THIS SECTION 4.2. THE GRANTOR AND LENDERS HEREBY WAIVE THEIR




                                       16
<PAGE>   17

RESPECTIVE RIGHTS TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION BASED UPON OR
ARISING OUT OF THIS SECURITY AGREEMENT OR ANY OF THE ACTIONS CONTEMPLATED
HEREIN, INCLUDING WITHOUT LIMITATION CONTRACT CLAIMS, TORT CLAIMS, BREACH OF
DUTY CLAIMS, AND ALL OTHER COMMON LAW OR STATUTORY CLAIMS. THE GRANTOR AND
LENDERS REPRESENT THAT EACH HAS REVIEWED THIS WAIVER AND EACH KNOWINGLY AND
VOLUNTARILY WAIVES ITS JURY TRIAL RIGHTS FOLLOWING CONSULTATION WITH LEGAL
COUNSEL. IN THE EVENT OF LITIGATION, A COPY OF THIS AGREEMENT MAY BE FILED AS A
WRITTEN CONSENT TO A TRIAL BY THE COURT.

         4.3 ATTORNEYS' FEES; EXPENSES. The Grantor agrees to pay, jointly and
severally upon demand all of Lenders' costs and expenses, including without
limitation reasonable attorneys' fees and legal expenses, incurred in connection
with the enforcement of this Security Agreement. Lenders may pay someone else to
help enforce this Security Agreement, and the Grantor shall pay the reasonable
costs and expenses of such enforcement. Costs and expenses include without
limitation Lenders' reasonable attorneys' fees and legal expenses whether or not
there is a lawsuit, including without limitation reasonable attorneys' fees and
legal expenses for bankruptcy proceedings (and including efforts to modify or
vacate any automatic stay or injunction), appeals, and any anticipated
post-judgment collection services. The Grantor also shall pay all court costs
and such additional fees as may be directed by the court.

         4.4 CAPTION HEADINGS. Caption headings in this Security Agreement are
for convenience purposes only and are not to be used to interpret or define the
provisions of this Security Agreement.

         4.5 NOTICES. All notices required to be given under this Security
Agreement shall be given in writing and shall be effective when actually
delivered or seven (7) days after being deposited in the United States mail,
first class, postage prepaid, addressed to the party to whom the notice is to be
given or, if via facsimile, when sent via facsimile transmission to the party to
whom the notice is to be given and confirmation of such transmission has been
received, at the address and/or facsimile number shown below:

         if to Lenders:

                  Palladin Opportunity Fund, LLC and Halifax Fund, L.P.
                  195 Maplewood Avenue
                  Maplewood, New Jersey 07040
                  Facsimile: (973) 313-6491

         With a copy to:

                  Kleinberg, Kaplan, Wolff & Cohen, P.C.
                  551 Fifth Avenue, 18th Floor
                  New York, New York 10176
                  Attention: Christopher P. Davis, Esq.
                  Facsimile: (212) 986-8866



                                       17
<PAGE>   18


         If to the Grantor

                  ZymeTx, Inc.
                  800 Research Parkway, Suite 100
                  Oklahoma City, Oklahoma 73104
                  Attention: G. Carl Gibson
                  Facsimile: (405) 271-1708

                  And

                  Phillips McFall McCaffrey McVay & Murrah, P.C.
                  Twelfth Floor
                  One Leadership Square
                  211 North Robinson
                  Oklahoma City, Oklahoma 73102
                  Attention: Douglas A. Branch, Esq.
                  Facsimile: (405) 235-4562

Any party may change its address for notices under this Security Agreement by
giving formal written notice to the other parties, specifying that the purpose
of the notice is to change the party's address. For notice purposes, the Grantor
agrees to keep Lenders informed at all times of the Grantor' current addresses.

         4.6 SEVERABILITY. The parties acknowledge and agree that the Lenders
are not agents or partners of each other, that all representations, warranties,
covenants and agreements of the Lenders hereunder are several and not joint,
that no Lender shall have any responsibility or liability for the
representations, warrants, agreements, acts or omissions of any other Lender,
and that any rights granted to "Lenders" hereunder shall be enforceable by each
Lender hereunder. If a court of competent jurisdiction finds any provision of
this Security Agreement to be invalid or unenforceable as to any person or
circumstance, such finding shall not render that provision invalid or
unenforceable as to any other persons or circumstances. If feasible, any such
offending provision shall be deemed to be modified to be within the limits of
enforceability or validity; however, if the offending provision cannot be so
modified, it shall be stricken, and all other provisions of this Security
Agreement in all other respects shall remain valid and enforceable and such
offending provision shall not be affected in any other jurisdiction.

         4.7 SUCCESSOR INTERESTS. Subject to the limitations set forth above on
transfer of the Collateral, this Security Agreement shall be binding upon and
inure to the benefit of the parties, their successors and assigns. The Grantor
shall not, however, have the right to assign this Security Agreement without the
prior written consent of Lenders which may be withheld for any reason in
Lenders' sole discretion.

         4.8 WAIVER. Lenders shall not be deemed to have waived any rights under
this Security Agreement unless such waiver is given in writing and signed by
Lenders. No delay or omission on the part of Lenders in exercising any right
shall operate as a waiver of such right or




                                       18
<PAGE>   19


any other right. A waiver by Lenders of a provision of this Security Agreement
shall not prejudice or constitute a waiver of Lenders' right otherwise to demand
strict compliance with that provision or any other provision of this Security
Agreement. No prior waiver by Lenders, nor any course of dealing between Lenders
and the Grantor, shall constitute a waiver of any of Lenders' rights or of any
of the Grantor's obligations as to any future transactions. Whenever the consent
of Lenders is required under this Security Agreement, the granting of such
consent by Lenders in any instance shall not constitute continuing consent to
subsequent instances where such consent is required and in all cases such
consent may be granted or withheld in the sole discretion of Lenders.

         4.9 INDEMNITY. Except to the extent caused directly by Lenders' gross
negligence or wilful misconduct, the Grantor agrees to indemnify, pay and hold
each Lender and the officers, partners, directors, employees, agents and
affiliates of each Lender (collectively, the "indemnitees") harmless from and
against any and all liabilities, obligations, losses, damages, penalties,
actions, judgments, suits, claims, costs, expenses and disbursements of any kind
or nature whatsoever (including, without limitation, the reasonable fees and
disbursements of counsel) that may be imposed on, incurred by, or asserted
against any indemnitee, in any manner relating to or arising out of this
Security Agreement and any action undertaken or contemplated hereby. This
indemnification shall survive the satisfaction and payment of the Indebtedness
and termination of this Security Agreement.




                            [SIGNATURE PAGE FOLLOWS]



                                       19
<PAGE>   20





         IN WITNESS WHEREOF, the parties hereto have caused this Security
Agreement to be executed as of the date first written above.

                                    ZYMETX, INC.


                                    By:
                                       ----------------------------------------
                                        Norman R. Proulx
                                        Chief Executive Officer


                                    PALLADIN OPPORTUNITY FUND, LLC.
                                    By: Palladin Asset Management, L.L.C.
                                        Managing Member


                                    By:
                                       ----------------------------------------
                                        Robert Chender
                                        Managing Member


                                    HALIFAX FUND, L.P.
                                    By: The Palladin Group, L.P.
                                        Attorney-in-Fact

                                    By: Palladin Capital Management, LLC
                                        General Partner


                                    By:
                                       ----------------------------------------
                                        Robert Chender
                                        Managing Member




                                       20
<PAGE>   21





                                   SCHEDULE A


                         IDENTITY AND ADDRESS OF LENDERS


INVESTOR

Palladin Opportunity Fund, LLC 195
Maplewood Avenue
Maplewood, N.J. 07040



Halifax Fund, L.P.
195 Maplewood Avenue
Maplewood, N.J. 07040












<PAGE>   22





                                   SCHEDULE B

                    IDENTIFICATION AND LOCATION OF COLLATERAL



                             PLEASE SEE ATTACHMENTS.