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                                                                    EXHIBIT 10.3

     AGREEMENT BETWEEN IVAX DIAGNOSTICS, INC. AND SIGMA DIAGNOSTICS

     This Distributorship Agreement (hereinafter the "Agreement") is between
IVAX DIAGNOSTICS, Inc., a corporation existing under the laws of Florida,
(together with its affiliates Delta Biologicals, Diamedix Corporation, and
Immunovision, Inc., hereinafter referred to as "IVAX Diagnostics"),and SIGMA
DIAGNOSTICS, Inc. (hereinafter "SIGMA"), a corporation existing under the laws
of Missouri.

     WHEREAS, IVAX DIAGNOSTICS desires to sell and/or market its products and
SIGMA desires to purchase certain of IVAX DIAGNOSTICS's products for resale to
customers; and

     WHEREAS, the parties desire to enter into an agreement setting forth the
terms of their relationship;

     NOW, THEREFORE, in consideration of the mutual covenants and agreements
contained herein, the parties do hereby agree as follows:

1.   Products. The product(s) of IVAX DIAGNOSTICS covered by this Agreement are
     set forth on Exhibit A attached hereto (hereinafter the "Product(s)"). For
     avoidance of doubt, "Product" or "Products" means only products purchased
     from IVAX DIAGNOSTICS, and marketed under a trademark or trade name of
     SIGMA. IVAX DIAGNOSTICS reserves the right to discontinue or modify the
     Products from time to time, and shall, to the extent practicable, give
     SIGMA at least six (6) months prior written notice before discontinuation
     or making changes to Product hardware and software that would have an
     impact on any of IVAX DIAGNOSTICS product verifications or validations, or
     changes in raw materials that would alter the operating principle of the
     Products or other changes that could impact product labeling or promotional
     literature; provided, however, that IVAX DIAGNOSTICS shall be required to
     provide SIGMA with only reasonable advance notice where such discontinuance
     or modification is required to comply with any applicable legal or
     regulatory requirement or the unanticipated modification or unavailability
     of raw material. Additional products may be added to Exhibit A by mutual
     consent of the Parties.

2.   Appointment and Acceptance.

     (a)  IVAX DIAGNOSTICS hereby appoints SIGMA as their distributor of the
          Product(s) and grants SIGMA the right and license to import, use,
          possess, market, sell and distribute the Product(s) in the United
          States and outside the United States (the "Territory") and the right
          to extend to Affiliates, sub-distributors and purchasers rights of the
          same scope as granted herein

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          to use, possess, market, sell and distribute Product(s) in the
          Territory subject to the provisions of Section 23 hereof.


     (b)  IVAX DIAGNOSTICS reserves the unlimited right to sell directly and
          through distributors (but specifically excluding distributors that
          manufacture or have manufactured ELISA kits in significant quantities
          in the Territory) products similar to the Product, under its own
          trademark or trade name.

          IVAX DIAGNOSTICS reserves the unlimited right to sell a product
          similar to the Product to Sanofi Diagnostics Pasteur, under any trade
          name.

3.   Term and Renewal.

     (a)  The term of this Agreement shall be for a period of three (3) years,
          becoming effective on May 1, 1999 (the "Inital Term"), and shall
          automatically renew- for additional and successive terms of one (1)
          year unless either party provides written notice of non-renewal at
          least ninety (90) days prior to the close of the Initial Term or of
          any anniversary date thereafter.

     (b)  The Agreement between the parties dated May 13, 1998 (the "Prior
          Agreement"), and each section thereof, is hereby terminated, and shall
          be of no further force or effect as of the after the effective date of
          this Agreement, except that products purchased by SIGMA under the
          Prior Agreement shall be subject to the provisions of this Agreement.

4.   Terms of Sale.

     (a)  The price for the Products is outlined in Exhibit A.

          The parties acknowledge that, in certain situations, SIGMA will face
          substantial competition in marketing the Products. In these highly
          competitive situations, IVAX DIAGNOSTICS will discuss with SIGMA the
          possibility of reducing the Purchase Price so that SIGMA is able to
          resell the Products at competitive prices.

     (b)  SIGMA shall be required to purchase a minimum of 550 Products in the
          Territory during the Initial Term as per the minimum obligation
          outlined in Exhibit A. Any outstanding orders placed by Sigma and any
          previous orders shall not be counted toward the 550 unit minimum.
          Minimum purchase after the Initial Term shall be mutually agreed upon
          between the parties in good faith.

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     (c)  Payment terms are net forty-five (45) days from date of invoice.

     (d)  Title and risk of loss shall pass to SIGMA upon release of Products
          for shipment by IVAX DIAGNOSTICS to the designated carrier. All
          freight, applicable insurance charges, taxes, duties and similar
          charges shall be the responsibility of SIGMA. IVAX DIAGNOSTICS will be
          responsible for contracting freight services, in accordance with
          Section 8(a) of this Agreement, for which SIGMA will be billed on a
          shipment by shipment basis. Products are subject to acceptance by
          SIGMA upon receipt in accordance with Section 13.

5.   Reciprocal Termination Rights. Either IVAX DIAGNOSTICS or SIGMA may
     terminate this Agreement for cause immediately by written notice upon the
     occurrence of any of the following events:

     (a)  If the other ceases to do business or otherwise terminates its
          business operations;

     (b)  If the other shall fail to promptly secure or renew any license,
          registration, permit, authorization or approval necessary for the
          conduct of its business in the manner contemplated by this Agreement
          or if any such license, registration, permit, authorization or
          approval is revoked or suspended and not reinstated within thirty (30)
          days;

     (c)  If the other breaches any material provision of this Agreement and
          fails to cure such breach within sixty (60) days of written notice
          describing the breach;

     (d)  If the other becomes insolvent or seeks protection under any
          bankruptcy, receivership, trust deed, creditors arrangement,
          composition or comparable proceeding, or if any such proceeding is
          instituted against the other (and not dismissed with sixty (60) days)
          ; or

     (e)  If a material representation of the other becomes false or misleading
          and the other party fails to render such representation true in all
          material respects within sixty (60) days of written notice describing
          the false or misleading representation.

6.   Rights Upon Termination. Any termination or expiration of 'the Agreement
     shall not release IVAX DIAGNOSTICS or SIGMA from paying any amount that may
     then be owed from any obligation at the date of termination hereunder. Each
     party understands that the rights of termination hereunder are

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     absolute. Neither party shall incur any liability whatsoever for any
     damage, loss or expenses of any kind suffered or incurred by the other (or
     for any compensation to the other) arising from or incident to any
     termination of this Agreement in accordance with the terms hereof whether
     or not such party is aware of any such damage, loss or expenses.
     Termination is not the sole remedy under this Agreement and, whether or not
     termination is effected; all other remedies will remain available.

     (a)  Orders. IVAX DIAGNOSTICS agrees that during the period between the
          notice.of termination and the effective date thereof, it will honor
          SIGMA's orders for Products.

     (b)  Returns or Exchanges. IVAX DIAGNOSTICS shall be obligated to accept
          for return any new Products in SIGMA's possession at the time of
          termination, for full credit of the original purchase price, provided
          however, that IVAX DIAGNOSTICS shall not be under such obligation if
          the Agreement is not renewed by either party or such termination was
          not caused by a default by IVAX DIAGNOSTICS, or if the Agreement is
          terminated by IVAX DIAGNOSTICS as a result of a default by SIGMA.

     (c)  Furnishing of spare parts. Notwithstanding termination of this
          Agreement, following such termination IVAX DIAGNOSTICS agrees to
          continue to provide after sales service in Italy and spare parts to
          SIGMA for SIGMA's customers, at the prices on IVAX DIAGNOSTICS price
          list attached as Exhibit F hereto.

7.   SIGMA's Duties. SIGMA shall:

     (a)  use reasonable commercial efforts to advertise and promote the sale of
          the Products in a commercially ethical manner, instructing its sales
          people to refrain from disparaging remarks about the competitive
          products of IVAX DIAGNOSTICS

     (b)  place a firm order six (6) weeks before expected delivery in
          quantities of five (5) or more. All purchase orders and invoices for
          Products are subject to the terms and conditions of this Agreement,
          which terms and conditions shall supersede any and all terms and
          conditions on SIGMA'S order form in effect from time to time.

     (c)  obtain advance written authorization from IVAX DIAGNOSTICS prior to
          returning any of the Products.

     (d)  maintain properly trained sales force of adequate size to represent
          and promote the sales of the Products and

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          provide instructions to customers in the use of the Products. SIGMA
          shall be responsible for developing its own marketing plan and system
          for distributing the Products.

     (e)  carry in stock an inventory of Products sufficient to meet the needs
          of SIGMA's customers in the Territory.

     (f)  apply for and obtain all necessary licenses, permits and other
          authorizations required by local law or regulation in relation to the
          promotion, marketing, distribution and supply of the Products in any
          jurisdiction in which SIGMA sells the Products.

     (g)  maintain separate and detailed accurate and complete records of all
          transactions in respect of the Products, including, but not limited
          to, such records as identify all customer purchases by Product and
          serial and/or lot number, and possess the capability to notify all
          purchasers in the event of a Product recall or corrective action.

     (h)  make no contracts or commitments on behalf of IVAX DIAGNOSTICS or make
          any promises or representations or give any warranties or guarantees
          with respect to the Products on behalf of IVAX DIAGNOSTICS.

     (i)  comply with all laws and regulations and requirements applicable to a
          seller of in-vitro diagnostics products, and with all laws and
          regulations and requirements of governmental agencies having
          jurisdiction within the Territory.

     (j)  offer to IVAX DIAGNOSTICS the exclusive right to develop reagents for
          use on the Products marketed by SIGMA that are not developed by
          SIGMA's primary developer, Zeus Scientific, Inc.; negotiate with IVAX
          DIAGNOSTICS in good faith for a period not to exceed thirty (30) days
          the terms and conditions of an agreement regarding such reagents
          before it offers such rights to any party other than Zeus Scientific,
          Inc.; and not grant such rights to any party other than Zeus
          Scientific on terms that are more favorable than the terms offered to
          IVAX DIAGNOSTICS.

8.   IVAX DIAGNOSTICS Duties. IVAX DIAGNOSTICS shall:,

     (a)  make reasonable efforts, in good faith, to ship SIGMA's orders for
          Products within six (6) weeks from date of order receipt, at the
          prices set forth in Section 4(a). SIGMA shall specify the method of
          shipment and insurance and IVAX DIAGNOSTICS shall make reasonable
          efforts, in good faith, to comply with such

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          specifications. If no such specification is made, or if the
          specification cannot be reasonably complied with after notice to SIGMA
          and an opportunity to resolve the issues surrounding IVAX DIAGNOSTICS
          alleged inability to comply, IVAX DIAGNOSTICS may select a reasonable
          manner of shipment and insurance.

     (b)  comply with all laws and regulations and requirements applicable to
          IVAX DIAGNOSTICS as a manufacturer of invitro diagnostic products,
          including obtaining the CE mark for the Products and IS09002
          registration, to the extent they are required.

     (c)  except as authorized in writing by SIGMA; refrain absolutely from
          using the trademark or trade name and logo of SIGMA in connection with
          the marketing, distribution and sale of any Product.

     (d)  provide reasonable technical assistance to SIGMA'S personnel necessary
          for the marketing of the Products.

     (e)  at IVAX DIAGNOSTIC's expense, provide SIGMA with one copy of the
          operator's manuals relating to the Product's use, and with such
          amendments thereto as subsequently become available. SIGMA shall have
          the right to make copies as needed.

     (f)  provide necessary documentation to assist SIGMA in meeting
          requirements to register Products in the Territory and comply with all
          laws and regulations, and requirements applicable to SIGMA as a
          distributor of in-vitro diagnostics products, and where possible,
          allow SIGMA to reference prior registrations by IVAX DIAGNOSTICS.

     (g)  provide SIGMA with copies of the 510(k) premarket notifications
          submitted for the Products if applicable, copies of current operators
          manuals for the Products, copies of documents describing
          specifications for the Products, and copies of all current and future
          correspondence with the FDA pertaining to the Products. IVAX
          DIAGNOSTICS will comply with the FDA's current GMP regulations in the
          manufacture of all Products. If needed to comply with any change in
          the law or FDA's GMP regulations or policies, Sigma shall be given
          the right to inspect IVAX DIAGNOSTICS manufacturing o; facilities for
          the Products and GMP records pertaining U) to the manufacture of the
          Products. If any action should be taken by the FDA to restrict or
          prevent the distribution of any of the Product for more than sixty
          (60) days, and such restriction is not due to any act or omission of
          SIGMA, then upon notice to IVAX DIAGNOSTICS, SIGMA shall have the
          right to terminate

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          this Agreement as to such Product. In such event, IVAX DIAGNOSTICS
          shall replace any affected inventory of Products under this section or
          refund to SIGMA the purchase price it paid to IVAX DIAGNOSTICS for
          such inventory if IVAX DIAGNOSTICS is unable to replace the Products
          with comparable inventory. In addition, IVAX DIAGNOSTICS shall replace
          or repurchase any affected inventory of Product, which SIGMA replaces
          or repurchases from SIGMA's customers, at the price SIGMA paid IVAX
          DIAGNOSTICS for such inventory.

     (h)  comply with the Federal Food, Drug, and Cosmetic Act. The Products
          comprising each shipment or other delivery hereafter made by IVAX
          DIAGNOSTICS to, or on the order of, SIGMA, as of the date of such
          shipment or delivery, shall be, on such date, not adulterated or
          misbranded within the meaning of the Federal Food, Drug, and Cosmetic
          Act.

     (i)  perform any necessary task to insure the Product complies with any
          changes or redefinition!s of standardization required by domestic and
          international scientific bodies covering minimum performance gu
          idelines, which are economically feasible; provided that IVAX
          DIAGNOSTICS shall be entitled to adjust the purchase price of any
          Product affected by any such change to the extent of IVAX DIAGNOSTICS
          actual cost. If IVAX-DIAGNOSTICS determines that the required change
          is not economically feasible, SIGMA shall have the right to pay the
          cost of such change and IVAX DIAGNOSTICS agrees to make such changes
          exclusively for Sigma.

     (j)  maintain sufficient inventories of spare parts for each Product in
          such quantities as is reasonably expected to be necessary or
          appropriate to handle the maintenance and repair claims of SIGMA's
          customers during the term hereof.

     (k)  offer its products, which are competitive to the Products in a
          commercially ethical manner, instructing its sales people (i) not to
          disclose to customers that IVAX DIAGNOSTICS manufactures the Products
          for SIGMA and (ii) to refrain from disparaging remarks about the
          Products.

     (1)  provide SIGMA with open channel improvements and throughput
          improvements similar to those IVAX DIAGNOSTICS may develop and
          implement for its own purposes during the term of this Agreement.

     (m)  during the term of this Agreement use its best efforts to modify the
          Product as required to maintain the

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          Product's competitiveness in the market place as SIGMA and IVAX
          DIAGNOSTICS shall mutually agree upon in good faith. If such
          modifications are to be made to the instrument purchased by SIGMA
          only, and are not used to modify the units that are sold by IVAX
          DIAGNOSTICS or Sanofi, then SIGMA shall be responsible for the cost
          associated with such modifications.

9.   Software updates and modifications. Updates and modifications made to the
     Product's software by IVAX DIAGNOSTICS shall be provided to SIGMA free of
     charge, whether or not such updates or modifications were requested by
     SIGMA. Software modifications requested by SIGMA to allow additional SIGMA
     products applications to operate on the Product shall be for the account of
     SIGMA. IVAX DIAGNOSTICS shall invoice SIGMA at its cost, and shall use its
     reasonable efforts to minimize the cost. IVAX DIAGNOSTICS shall be
     responsible for validation of all software updates and modifications, and
     shall provide a sufficient quantity of the updates and modification
     necessary to replace the software in every unit ever purchased by SIGMA.

10.  After sales service.

     (a)  SIGMA shall provide all labor, transportation and related expenses for
          after sales warranty service for the maintenance and repair of the
          Products worldwide, PxcPnt for Ttaly, which shall be the
          responsibility of IVAX DIAGNOSTICS and shall be performed by IVAX
          DIAGNOSTICS in accordance with the Service Plan as outlined in Exhibit
          E attached hereto. Warranty services shall include servicing all
          warranty claims and making necessary adjustments, including
          preventative maintenance from time to time as may be necessary to
          insure proper and efficient operation. IVAX DIAGNOSTICS shall provide
          replacement parts for all Products worldwide during any warranty
          period free of charge to SIGMA. Such replacement parts shall be
          tracked according to the serial number of the Products in which the
          parts are installed, and IVAX DIAGNOSTICS shall be provided a copy of
          the service report documenting such part replacement. All parts, which
          are removed from the Products and replaced under warranty, shall be
          returned at IVAX DIAGNOSTIC'S expense to IVAX DIAGNOSTICS and become
          the property of IVAX DIAGNOSTICS. After the warranty period, IVAX
          DIAGNOSTICS will charge SIGMA for replacement parts at the prices as
          outlined in the Exhibit F.

     (b)  It is expressly understood that from the effective date of this
          Agreement until a date not later than September 30, 1999 (the
          "Transition Period"), IVAX DIAGNOSTICS

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          agrees to the following:

          (1)  SIGMA and IVAX DIAGNOSTICS will work together to provide service
               as required during the Transition Period. Each party will pay
               their related expenses during the transition period.

          (2)  During the Transition Period, IVAX DIAGNOSTICS will train SIGMA
               service personnel at SIGMA's facilities in St. Louis, MO and
               Munich, Germany. There will need to be two or more courses held
               in St. Louis. SIGMA shall pay all travel expense associated with
               such training, which shall take approximately two (2) weeks per
               course.

     (c)  During the term of this Agreement IVAX DIAGNOSTICS will provide
          service assistance and/or training as reasonably requested by SIGMA.
          SIGMA shall pay all reasonable travel expenses associated-with such
          assistance and/or training. IVAX DIAGNOSTICS shall staff a technical
          service hotline (the "Product Service Hotline") for SIGMA 24 hours per
          day 7 days per week during the Transition Period. Thereafter; IVAX
          DIAGNOSTICS shall operate the Product Service Hotline during normal
          business hours. (9am-6pm Monday through Friday except Holidays) SIGMA
          shall instruct its customers to direct any Product inquiries to SIGMA.
          The Products Service Hotline is available to provide technical
          assistance back up to SIGMA's EIA technical support.

     (d)  During the term of this Agreement, SIGMA will monitor reliability and
          durability of the Product. Issues identified as causing excess field
          service will be investigated and resolved by IVAX DIAGNOSTICS at IVAX
          DIAGNOSTIC's expense.

11.  Demonstrations, Installations and Customer Training. SIGMA shall be
     responsible for all installations, customer training and infield Product
     demonstrations, except that IVAX Diagnostics will. continue to
     do.installation at their expense during the transition period as requested
     by SIGMA. Installation and customer training services shall include giving
     operating and maintenance instructions, installing Products (other than
     spare and replacement parts), performing all service necessary at the time
     of delivery and making installation inspection and necessary adjustments at
     the time of delivery to ensure proper and efficient operation.

12.  Future Product Development. The Parties agree to collaborate with each
     other, in preference to collaborations with other parties, in any future
     development of new

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     Products in the Enzyme Immunoassay ("EIA") instrumentation field on the
     following terms.

     (a)  SIGMA shall inform IVAX DIAGNOSTICS in writing whether or not SIGMA
          wants to implement a new product idea offered by IVAX DIAGNOSTICS
          within three (3) months after the date SIGMA receives a written
          concept of the new product idea. If SIGMA wants to implement a new
          product idea presented by IVAX DIAGNOSTICS, the parties will negotiate
          in good faith to agree on the terms of developing and distributing
          such new product. If IVAX DIAGNOSTICS does not receive such written
          notice from SIGMA, or if the parties are unable to reach agreement on
          the terms of a development and distribution agreement under similar
          terms and conditions of this Agreement within three (3) months after
          SIGMA gives notice of its interest, IVAX DIAGNOSTICS shall be free to
          develop and distribute this new product, either on its own or in a
          collaboration with another party. However, such research and
          development shall not negatively affect IVAX DIAGNOSTICS' performance
          under this Agreement.

     (b)  IVAX DIAGNOSTICS shall inform SIGMA in writing whether or not IVAX
          DIAGNOSTICS wants to implement a new product idea offered by SIGMA
          within three (3) months after the date IVAX DIAGNOSTICS received a
          written concept of the new product idea. If IVAX DIAGNOSTICS does not
          receive such written notice from SIGMA, or if the parties are unable
          to reach agreement on the terms of a development and distribution
          agreement under similar terms and conditions of this Agreement, within
          three (3) months after SIGMA gives notice of its interest, IVAX
          DIAGNOSTICS shall be free to develop and distribute this new product,
          either on its own or in collaboration with another party. However,
          such research and development shall not negatively affect SIGMA's
          performance under this Agreement.

13.  Performance Standards.

     (a)  Quality Specifications and Characteristics. IVAX DIAGNOSTICS shall
          deliver to SIGMA Products having the quality specifications agreed
          upon by the parties as set forth in Exhibit B ("Quality
          Specifications"). [These Quality Specifications and Characteristics
          may be modified from time to time to meet the future requirements of
          the parties. In such cases, the parties agree to negotiate in good
          faith to find a solution that can be mutually agreed to by the
          parties]

     (b)  Certificates of Analysis. Concurrent with shipment, IVAX DIAGNOSTICS
          shall fax to SIGMA Certificates of

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          Analysis, in the form set forth in Exhibit B, for each Product and
          each accessory kit sold to SIGMA, confirming that the Product and
          accessory kit meets the Quality Specifications.

     (c)  Product Acceptance. SIGMA shall accept the Products based on the
          Certificate of Analysis delivered by IVAX DIAGNOSTICS. Should at
          anytime during the warranty period or service contract term if covered
          by a valid service contract the Product fails to meet the Quality
          Specifications, and SIGMA service is unable to get the product to meet
          the quality specifications, SIGMA shall notify IVAX DIAGNOSTICS hereof
          and immediately thereafter provide IVAX DIAGNOSTICS with the problems
          associated with the Product. IVAX DIAGNOSTICS shall have 20 days after
          receipt of SIGMA's notice within which to accept or reject SIGMA's
          claims. If, following a review of the problems and after conducting
          its own tests, IVAX DIAGNOSTICS agrees that such Product does not
          conform to the Quality Specifications, IVAX DIAGNOSTICS shall provide
          SIGMA, free of any additional charge, with new deliveries of the same
          quantity of the Products affected or items necessary to make the
          Product acceptable to Sigma, or, in IVAX DIAGNOSTICS discretion and at
          its cost, IVAX DIAGNOSTICS may promptly reprocess the nonconforming
          Products to meet the Quality Specifications. In either event, SIGMA
          shall return, at IVAX DIAGNOSTIC's expense, the particular lot or
          shipment of the Product, which does not comply with the Quality
          Specifications if requested to do so by IVAX DIAGNOSTICS. Any dispute
          arising under this Section 13(c) shall be resolved by arbitration as
          outlined in Section 25.

14. Product Recall

     (a)  IVAX DIAGNOSTICS shall maintain an appropriate record of all claims
          made or to be made regarding the Products performance.

     (b)  Each party shall keep the other informed of any.formal action relating
          to any specific lot of Product sold to SIGMA hereunder by any
          regulatory agency of any state, national government, or government
          agency having jurisdiction.

     (c)  Should any governmental or corporate action require a medical device
          reportable (MDR) event, a medical device vigilance system report
          (MDVS), a recall or field corrections, or withholding from market of
          Product sold by IVAX DIAGNOSTICS to SIGMA, SIGMA shall bear the
          reasonable, direct costs and expenses of the MDR, MDVS, recall or
          field correction if such action is the result

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          of any fault or omission attributable to SIGMA. IVAX DIAGNOSTICS shall
          bear the reasonable, direct costs and expenses of the MDR, MDVS,
          recall or field correction and the actual costs of replacing the
          Products if such action is the result of any fault or omission
          attributable to IVAX DIAGNOSTICS. Should such MDR, MDVS, recall or
          field correction result from the fault of both parties, the parties
          shall share the costs of Products and the actual cost of replacing the
          Products in proportion to their respective degree of fault.

15.  Product Complaints

     (a)  Should either party experience any quality problem of any specific
          lot(s) of Product supplied to SIGMA by IVAX DIAGNOSTICS, such party
          will notify the other in writing by facsimile prior to the initiation
          of a MDR, MDVS, field correction or recall and the parties shall
          consult with each other regarding the proper course of action,
          provided that each party retains the right to correct quality
          problems, as it deems appropriate, with or without the concurrence of
          the other. All information about Product complaints shall be
          considered "Confidential Information" under the terms of this
          Agreement.

     (b)  Either party shall immediately notify the other party in writing
          should it become aware of any defect or condition that renders any
          lot(s) of Product supplied by IVAX DIAGNOSTICS to SIGMA in violation
          of the United States Food, Drug and Cosmetic Act, or of a similar law
          of any jurisdiction or country where the Product is sold. The parties
          shall share with each other all data on confirmed lot specific Product
          complaints including, but not limited to, complaints or information
          regarding performance and/or allegations or reports of any negative
          effect from the use or misuse of such affected lot of Products as soon
          as such data is available. Each party will provide reasonable
          assistance to the other in resolving customer complaints to the extent
          the complaint arises out of any fault or omission of the party whose
          assistance is requested. However, SIGMA shall have sole responsibility
          and authority to interact directly with SIGMA's customers in the
          resolution of such complaints and IVAX DIAGNOSTICS agrees that it will
          only interact with SIGMA in such matters.

     (c)  IVAX DIAGNOSTICS shall evaluate and investigate all customer
          complaints in connection with the Products which may be brought to its
          attention, in writing, by SIGMA; provided such complaints have been
          confirmed by SIGMA using the same standards for confirmation which

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          SIGMA's uses for products other than the IVAX DIAGNOSTICS Products and
          which are believed in good faith by SIGMA to arise out of a fault or
          omission attributable to IVAX DIAGNOSTICS. Within twenty (20) calendar
          days following receipt from SIGMA of the original notification of each
          such complaint, IVAX DIAGNOSTICS agrees to provide SIGMA with a
          written interim or final complaint investigation report. All such
          Product complaints reported to IVAX DIAGNOSTICS by SIGMA shall be
          reviewed monthly by IVAX DIAGNOSTICS until closure, and a summary
          report thereof will be provided by IVAX DIAGNOSTICS to SIGMA.

     (d)  IVAX DIAGNOSTICS will report to SIGMA all data and/or information
          pertaining to adverse reports on any lot of Product supplied by IVAX
          DIAGNOSTICS for distribution by SIGMA, which would have a materially
          adverse impact on performance of the Products.

16.  Warranties.

     (a)  IVAX DIAGNOSTICS warrants that the Products which are the subject of
          existing 510(k) premarket notifications have not been significantly
          changed or modified in design, components, method of manufacture or
          intended use from the Products as described in those 510 (k) premarket
          notifications, and will notify Sigma in advance of any changes in
          accordance with Section 1.

     (b)  Limited Warranty. The Products are subject to warranties in favor of
          SIGMA and to disclaimers of warranties and liability for damages
          consequential or otherwise, as provided in IVAX DIAGNOSTICS Limited
          Warranty, as it may be modified by IVAX DIAGNOSTICS from time to time
          (the "IVAX DIAGNOSTICS Limited Warranty"). A copy of IVAX DIAGNOSTICS
          Limited Warranty in effect as of the date hereof is attached in
          Exhibit C. Such warranty shall run for the applicable time period
          ("Warranty Period") specified in IVAX DIAGNOSTICS Limited Warranty, as
          it may be modified from time to time. With respect to any Product that
          is delivered to a customer of SIGMA's in a new and unused condition,
          the Warranty Period shall begin at the time of the installation of the
          Product at such customer's facility. With respect to any Product SIGMA
          removes from its inventory and uses for any reason and is ultimately
          sold to a customer of SIGMA, (i) the Warranty Period shall begin on
          the date SIGMA first installs the Product and, (ii) SIGMA shall
          promptly notify IVAX DIAGNOSTICS of the Product's installation.
          In no event will the warranty period exceed eighteen (18) months from
          the date of shipment from IVAX DIAGNOSTICS. For purposes of
          clarification, IVAX

                                       13
<PAGE>

          DIAGNOSTICS will not make, and shall not be deemed to make, any
          representation or warranty to any of SIGMA's customers, it being
          acknowledged and agreed by SIGMA that the representations and
          warranties of IVAX DIAGNOSTICS herein are for the sole benefit of
          SIGMA. SIGMA shall not represent to any of its customers that IVAX
          DIAGNOSTICS is making any representation or warranty to such
          customers, and any representation or warranty made by SIGMA to any of
          its customers shall not obligate IVAX DIAGNOSTICS in any way, and
          SIGMA shall indemnify and hold IVAX DIAGNOSTICS harmless against any
          claim, damage or expense, including without limitation reasonable
          attorneys' fees, incurred by IVAX DIAGNOSTICS as a result of any
          unauthorized representation or warranty made by SIGMA.

     (c)  IVAX DIAGNOSTICS warrants that all Products manufactured and supplied
          under this Agreement shall at the time of shipment meet the Quality
          Specifications of IVAX DIAGNOSTICS. IVAX DIAGNOSTICS further warrants
          that prior to shipment to SIGMA, all of its standard tests and quality
          control procedures have been carried out in relation to each lot of
          the Products with satisfactory results. The limited warranty to SIGMA
          set forth in this Agreement shall control over any warranty provisions
          which may be set forth in SIGMA's Product literature and SIGMA shall
          hold IVAX DIAGNOSTICS harmless from any and all damages and expenses
          which IVAX DIAGNOSTICS may incur as a result of unauthorized SIGMA
          warranties or representations. IVAX DIAGNOSTICS MAKES NO WARRANTY
          EXPRESSED OR IMPLIED WITH RESPECT TO THE PRODUCTS BEYOND THAT WHICH IS
          SET FORTH IN THIS AGREEMENT INCLUDING THE WARRANTIES OF
          MERCHANTABILITY AND FITNESS FOR ANY PARTICULAR PURPOSE.

     (d)  Upon its verification of any claim of defect or nonconformity of any
          unit of the Product arising out of a fault or omission attributable to
          IVAX DIAGNOSTICS, during the term of this Agreement, IVAX DIAGNOSTICS
          will provide SIGMA with a replacement unit to the extent necessary to
          honor IVAX DIAGNOSTICs warranties contained in Section 13(a) hereof,
          or make good any shortages or non-completed deliveries and shall pay
          all associated freight and insurance associated therewith.

     (e)  IVAX DIAGNOSTICS liability under any legal or equitable theory to
          SIGMA with respect to the Products and/or the relationship described
          in this Agreement shall be limited to the replacement of the unit, or
          if impractical, return of the purchase price paid by SIGMA for such
          unit.

     (f)  As of the date hereof, IVAX DIAGNOSTICS warrants that

                                       14
<PAGE>

          it has no knowledge that the manufacture, use or sale of all or any of
          the Products under this Agreement, nor any method of using such
          Products infringes on any patent or other intellectual property right
          of a third party, and IVAX DIAGNOSTICS has not received any
          notification from any third party alleging that the manufacture, use
          or sale of any such Product does or would infringe any patent or other
          intellectual property.

17.  Packaging and Intellectual Property. IVAX DIAGNOSTICS shall be responsible
     for packaging and labeling the Products. SIGMA will distribute the Products
     only with all appropriate labeling, packaging, and Product literature and
     only under SIGMA's applicable trademarks and trade names and not with IVAX
     DIAGNOSTIC's trademarks or trade names. SIGMA recognizes IVAX DIAGNOSTICS
     right, title and interest in its patents, trademarks, trade names and
     copyrights, trade secrets and proprietary information in connection with
     the Products, and SIGMA shall not claim any ownership right thereto
     inconsistent with this Agreement, or dispute the validity thereof. In the
     event any third party shall contest IVAX DIAGNOSTICS rights to its patents,
     trademarks, trade names or copyrights, trade secrets or propriety rights,
     SIGMA shall, at IVAX DIAGNOSTICS sole expense, render reasonable assistance
     to IVAX DIAGNOSTICS in defending such claims. In the event that any third
     party shall contest the validity of any trademark or trade name of SIGMA
     used on or in relation to a Product, SIGMA will, at its own expense, defend
     and indemnify IVAX DIAGNOSTICS against any claim brought by such third
     party and will reimburse IVAX DIAGNOSTICS for all reasonable expenses
     incident to the adoption and implementation of a new SIGMA trademark or
     trade name for the Products.

18.  Compliance With Other Agreements. Each party represents and warrants that
     the execution and delivery by it of this Agreement and the performance by
     it of its obligations hereunder will not, with or without the giving of
     notice or the passage of time, violate any judgement, writ, injunction or
     order of any court, arbitration or governmental agency or conflict with,
     result in the breach of any provisions of, or the termination of, or
     constitute a default under, any agreement to which IVAX DIAGNOSTICS or
     SIGMA is a party or by which it is or may be bound.

19.  Indemnity.

     (a)  Except as limited by the remainder of this paragraph, IVAX DIAGNOSTICS
          hereby agrees to indemnify SIGMA against claims of third parties for
          injuries to their persons arising from the use of Products supplied by
          IVAX DIAGNOSTICS to SIGMA hereunder. This indemnity

                                       15
<PAGE>

          shall not apply to, and IVAX DIAGNOSTICS shall not be liable for,
          claims for injuries caused by or arising from:

          (1)  any act or failure to act on the part of SIGMA, its employees,
               representatives, agents, subdistributors or affiliates in
               packaging, handling, storing, promoting or otherwise distributing
               such Products; or

          (2)  any representation or warranty concerning the Products made by or
               on behalf of SIGMA and not specifically authorized by IVAX
               DIAGNOSTICS; or

          (3)  claims where the use of the Products by any customer was not in
               accordance with the use prescribed by IVAX DIAGNOSTICS; or

          (4)  SIGMA'S failure to disseminate to purchasers or end-users any
               Product Information which IVAX DIAGNOSTICS has made available to
               SIGMA; or

          (5)  claims where IVAX DIAGNOSTICS has not been notified in writing
               within thirty (30) days of SIGMA's first notice of the claim; or

          (6)  claims where SIGMA fails to furnish evidence in its possession or
               fails to fully cooperate with IVAX DIAGNOSTICS in preparing the
               defense; or

          (7)  claims where IVAX DIAGNOSTICS is not given the option to assume
               the sole defense of the claim at IVAX DIAGNOSTIC'S expense.

     (b)  Except as limited by the remainder of this paragraph, SIGMA hereby
          agrees to indemnify IVAX DIAGNOSTICS against claims of third parties
          arising from the use of Products supplied by IVAX DIAGNOSTICS to SIGMA
          hereunder. This indemnity shall not apply to, and SIGMA shall not be
          liable for, claims caused by or arising from:

          (1)  any act or failure to act on the part of IVAX DIAGNOSTICS, its
               employees, representatives, agents or affiliates in
               manufacturing, testing, packaging, labeling, handling or storing
               such Products; or

          (2)  the breach of any representation or warranty concerning the
               Products made by or on behalf of IVAX DIAGNOSTICS; or

          (3)  claims where SIGMA has not been notified in

                                       16
<PAGE>

          writing within thirty (30) days of IVAX DIAGNOSTICS' first notice of
          the claim; or

          (4)  claims where IVAX DIAGNOSTICS fails to furnish evidence in its
               possession or fails to fully cooperate with SIGMA in preparing
               the defense or

          (5)  claims where SIGMA is not given the option to assume the sole
               defense of the claim at SIGMA's expense.

     (c)  IVAX DIAGNOSTICS shall indemnify SIGMA from any claims of.patent
          infringement relating to a Product subject to this Agreement provided
          SIGMA gives IVAX DIAGNOSTICS notice within thirty (30) days of SIGMA's
          first notice of the claim, and permits IVAX DIAGNOSTICS to assume the
          sole defense of the claim at IVAX DIAGNOSTICS expense; provided,
          however, that the claim is not based on (i) the sale or use of any
          Product in combination with any other product which is not
          specifically authorized by IVAX DIAGNOSTICS; (ii) the application of
          any Product in any manner not specifically authorized by IVAX
          DIAGNOSTICS.

     (d)  SIGMA shall indemnify IVAX DIAGNOSTICS from any claims of trademark
          infringement relating to a Product subject to this Agreement,
          provided IVAX DIAGNOSTICS gives SIGMA notice within thirty (30) days
          of IVAX DIAGNOSTICS' first notice of the claim, and permits SIGMA to
          assume the sole defense of the claim at SIGMA'S expense; and provided
          that the claim is based on the use of a SIGMA trademark or trade name.

     (e)  Not withstanding anything above to the contrary, in the event of a 3rd
          party claim arising out of this Agreement, in which neither IVAX
          DIAGNOSTICS or SIGMA is in breach of this Agreement or is negligent,
          each party shall pay its respective legal expenses and damages caused
          by such claim.

20.  Force Majeure. Neither party shall be responsible for any failure to
     perform due to causes beyond its control. These causes shall include, but
     not be limited to, fire, storm, flood, earthquake, explosion, wars, riots,
     civil disorder, sabotage; quarantine restrictions, labor disputes, labor
     shortages, transportation embargoes, or failure or delays or disruption in
     manufacturing process, curtailment of or failure in obtaining fuel or
     electrical power, or the acts of any governmental authority, or
     instrumentality's, orders of any court or tribunal whether foreign or
     domestic, exchange restrictions, acts of God, acts of the Federal
     Government or any agency thereof, acts of any state or local government or
     agency thereof, or shortage of materials or

                                       17
<PAGE>

     any similar or dissimilar occurrence beyond the reasonable control of the
     party which is prevented, interrupted or delayed in the performance of its
     obligations hereunder. In no event shall IVAX DIAGNOSTICS be under any
     obligations to purchase Products or similar products from any third party
     in order to supply same to SIGMA hereunder. Any force majeure event shall
     not excuse performance by the party but shall delay performance, unless
     such force majeure continues for a period in excess of one hundred thirty
     five(135) days. In such event, the party seeking performance, as its sole
     and exclusive remedy, many cancel its obligations under this Agreement.

21.  Insurance. IVAX DIAGNOSTICS and SIGMA shall keep in force during the term
     of this Agreement product liability insurance, in such amounts as may be
     customary for like sized businesses undertaking like responsibilities to
     those contemplated by this Agreement. SIGMA and IVAX DIAGNOSTICS shall
     submit a certificate of insurance to the other evidencing such coverage
     upon written request therefor.

22.  Confidentiality.

     (a)  Confidentiality Defined. For the purposes of this Agreement, the term
          "Confidential Information" shall be any information relating to the
          Products, including information embodying concepts, ideas, techniques,
          proprietary information,- know-how, formulations, market data,
          customer lists, product specifications and accounting data which is
          disclosed by one party hereto to the other.

     (b)  Non-Disclosure. During the period that this Agreement remains in
          effect and for a period of three (3) years following termination
          hereof, each party (except as is explicitly otherwise required hereby)
          shall keep confidential, shall not use for itself or for the benefit
          of others and shall not copy or allow to be copied in whole or in part
          any Confidential Information disclosed to such party by the other. The
          obligation of confidentiality imposed upon the parties by the
          foregoing paragraph shall not apply with respect to any alleged
          Confidential Information which:

          (1)  is known to the recipient thereof, as evidenced by said
               recipient's written records, prior to receipt thereof from the
               other party hereto;

          (2)  is disclosed to said recipient after the date hereof by the third
               party who has the right to make such disclosures and who does not
               violate any confidentiality agreement with the affected party
               hereto;

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<PAGE>

          (3)  is or becomes a part of the public domain through no fault of the
               said recipient; or

          (4)  is required by law or judicial or administrative process to be
               disclosed.

     (c)  IVAX DIAGNOSTICS and SIGMA shall agree to keep confidential and not
          disclose to third parties, the contents of this Agreement except as
          required by law or stock exchange rules, in which case the party
          required to disclose confidential information shall provide the other
          party with as much notice as is practicable.

     (d)  Each party agrees to limit access to Confidential Information to
          employees and agents having a need to know and to protect Confidential
          Information to the same extent as it protects its own trade secrets.

23.  Appointment of Sub-Distributors. SIGMA may assign, sublicense, delegate, or
     otherwise transfer the performance of the rights and obligations hereunder
     to qualified and reputable sub-distributors, provided, however, that: (i)
     SIGMA shall be liable to IVAX DIAGNOSTICS for the errors, negligent acts
     and omissions of-its sub-distributor's as if such errors, negligent acts
     and omissions were its own, including any breach of any provision of this
     Agreement by the sub-distributors; (ii) SIGMA shall have and retain full
     control of any sub-distributors utilized, and shall be responsible for the
     performance by any sub-distributor; and (iii) SIGMA shall not be relieved
     of the responsibility for the proper performance and completion of the
     sub-distributed portions of its obligations hereunder.

24.  Successors. This agreement shall be binding upon the successors of IVAX
     DIAGNOSTICS and SIGMA, including successors who acquire the business assets
     of IVAX DIAGNOSTICS and SIGMA.

25.  Resolution of Disputes. In the event of any controversy or claim arising
     under or in relation to this agreement, including any issue about payment
     of amounts due, the parties shall, in good faith, attempt to resolve the
     controversy or claim by negotiation. If the controversy or claim cannot be
     resolved within sixty (60) days, then it shall be settled exclusively by
     arbitration in accordance with the Arbitration Rules of the American
     Arbitration Association (AAA) and shall be held in Atlanta, GA. There shall
     be three arbitrators: one selected by the party who requests arbitration
     who shall notify the other party of the person selected at the time that
     notice of arbitration is sent; one selected by the other party within ten
     (10) days of receipt of notice of arbitration and one selected by the

                                       19
<PAGE>

     parties jointly within ten (10) calendar days thereafter or, failing their
     agreement, selected pursuant to the rules of the AAA. No arbitrator shall
     be related to, employed by, or have at any time a substantial ongoing
     business relationship with any party hereto or any of their respective
     affiliates. The losing party in the arbitration shall reimburse the
     prevailing party for all costs and expenses, including reasonable
     attorney fees, incurred in connection with the arbitration. The decision of
     the arbitrators shall be final and binding on the parties and judgement
     upon the award rendered by the arbitrators may be entered by any court
     having jurisdiction thereof. The provisions of this arbitration clause
     shall not be applied to the determination of questions affecting validity
     or scope of any trademarks or other intellectual property rights.

26.  Notices. Any notice or other communication required or that shall be given
     pursuant to this Agreement shall be deemed sufficient if delivered
     personally, sent by facsimile, telegraph, or sent by certified, registered
     or express mail, postage prepaid to the address or facsimile number set
     forth below:

     To IVAX DIAGNOSTICS:                          WITH A COPY TO:
     IVAX DIAGNOSTICS, INC.                        IVAX CORPORATION
     4400 Biscayne Blvd.                           4400 Biscayne Blvd.
     Miami, FL 33127                               Miami, FL 33137
     Facsimile No: (305) 324-2395                  Facsimile No: (305)575-6049
     Attn: President                               Attn: General Counsel

     To SIGMA:
               Sigma Diagnostics
               545 South Ewing Avenue
               St. Louis, Missouri 63103
               Facsimile No: (314) 534-8461
               Attn: Vice President, Administration

     Either party may change the address to which notice to it to be given, as
     provided herein.

27.  Entire Agreement. This Agreement and the exhibits referred to herein
     constitute the entire agreement between the parties and supersede all prior
     proposals, communications, representations and agreements, whether written
     or oral, with respect to the subject matter hereof. No change to the
     written terms of this Agreement shall be made except by written
     instrumentation executed by the parties hereto.

28.  No Waiver. The failure of either party to enforce at any time any of the
     provisions of this Agreement shall not be construed to be a waiver of those
     provisions or of the right of that party thereafter to enforce those
     provisions.

                                       20
<PAGE>

29.  Severability. If any provision of this Agreement is or becomes or is deemed
     invalid, illegal or unenforceable in any jurisdiction in which the
     Agreement is sought to be enforced, (a) such provision shall be deemed and
     amended to conform to applicable laws of such jurisdiction so as to be
     valid and enforceable or, if it cannot be so amended without materially
     altering the intention of the parties, it shall be stricken; (b) the
     validity, legality and enforceability of such provision will not in any way
     be affected or impaired thereby in any other jurisdiction; and (c) the
     remainder of this Agreement shall remain in full force and effect.

30.  Headings. The headings of this Agreement are included only for ease of
     reference and shall not affect the interpretation of this Agreement in any
     manner.

31.  Counterparts. This Agreement may be executed in any number of counterparts,
     each of which shall be deemed an original but all of which together shall
     constitute one and the same instrument.

32.  No Third Party Rights. The provisions of this Agreement are for the
     exclusive benefit of the parties to this Agreement, and no other party
     (including without limitation any creditor of any party to this Agreement)
     shall have any right or claim against any party to this Agreement by reason
     of those provisions or be entitled to enforce any of those provisions
     against any party to this Agreement.

33.  Relationship of Parties. This Agreement shall not constitute or be
     construed as creating a partnership or joint venture between SIGMA and IVAX
     DIAGNOSTICS, and neither party shall be liable for any debts or obligations
     of the other party.

34.  Limitation of Liability. Neither SIGMA nor IVAX DIAGNOSTICS nor any of
     their affiliates, employees, agents, officers or subcontractors shall have
     any liability for special, incidental, consequential or punitive damages or
     for economic loss as a result of any breach of this Agreement.

35.  Performance by Affiliates. SIGMA acknowledges and agrees that IVAX
     DIAGNOSTICS may perform certain of its obligations hereunder through its
     affiliates.

                                       21
<PAGE>

36.  THIS AGREEMENT CONTAINS A BINDING ARBITRATION PROVISION, WHICH MAY BE
     ENFORCED BY THE PARTIES.

IN WITNESS WHEREOF, the parties have caused this Agreement to be executed by
their duty authorized officers or authorized representatives

IVAX DIAGNOSTICS, INC.


By: /s/ GIORGIO D'URSO
    ---------------------------

Title: President
       ---------------------------

Date: 26 April 1999
      ---------------------------

SIGMA DIAGNOSTICS INC.


By: /s/ Robert Monaghan
   ---------------------------

Title: President
       ---------------------------

Date: 22 April 1999
      ---------------------------

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