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                                                               EXHIBIT 10(m)(ix)


                              EMPLOYMENT AGREEMENT


         EMPLOYMENT AGREEMENT, dated as of the 10th day of March 1998, between
CN Biosciences, Inc., a Delaware corporation (the "Company") and Ben
Matzilevich (the "Employee").

         1.      Effective Date.  This Employment Agreement shall become
effective on the 3rd day of April, 1998 (the "Effective Date").

         2.      Employment.  The Company hereby employs the Employee and the
Employee hereby accepts employment all upon the terms and conditions herein set
forth.

         3.      Duties.  The Employee is engaged  as Vice President, Market
Development/Niche Applications and will report to the Chairman and Chief
Executive Officer of the Company and hereby promises to perform and discharge
well and faithfully all duties of this position.  The important elements of
this position entail the identification of product opportunities associated
with high growth life science niche applications, the sourcing, licensing
and/or internal development of such products and the assembling of these
products into a niche catalogue that is then distributed and represented in the
market place.  The responsibilities of this position include being the
architect as well as the executor with the end result being to develop the
Company into a premier, innovative life science entity within the industry.

         4.      Extent of Services.  The Employee shall devote his entire
time, attention and energies to the business of the Company and shall not
during the term of this Employment Agreement be engaged in any other business
activity whether or not such business activity is pursued for gain, profit or
other pecuniary advantage; but this shall not be construed as preventing the
Employee from investing his personal assets in businesses which do not compete
with the Company in such form or manner as will not require any services on the
part of the Employee in the operation of the affairs of the companies in which
such investments are made and in which his participation is solely that of an
investor, nor shall this be construed as preventing the Employee from
purchasing securities in any corporation whose securities are regularly traded
provided that such purchases shall not result in his collectively owning
beneficially at any time one percent (1%) or more of the equity securities of
any corporation engaged in a business competitive to that of the Company,
without the express prior written consent of the Company.





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         5.      Compensation.

                 (a)     For services rendered under this Employment Agreement,
the Company shall pay the Employee a salary determined annually by the
Compensation Committee of the Board of Directors (the "Base Salary"), payable
(after deduction of applicable payroll taxes as an employee in the State of
Massachusetts) in equal bi-weekly installments.  The Employee shall also be
eligible for and participate in such fringe benefits as shall be generally
provided to executives of the Company,  including medical insurance and
retirement programs which may be adopted from time to time during the term
hereof by the Company.  On an annual basis, the Compensation Committee shall
review Employee's salary and make such adjustment as may be warranted based upon
Employee performance, Company financial performance, economic conditions, etc.

                 (b)      At the conclusion of each Fiscal Year, the Employee
shall be eligible for, and the Compensation Committee in its sole discretion,
may award an executive bonus up to a maximum of 35% of Base Salary, based on
the achievement of mutually acceptable objectives.

                 (c)      The Company shall provide the Employee with the full
use of the Company van while the Employee is in San Diego.  In the event that
the Company requires the use of the Company van, the Company shall provide
Employee with a medium size rental vehicle.

         6.      Paid Time Off.  During the term of this Employment Agreement,
the Employee shall be entitled to twenty-nine (29) paid days off pursuant to
the Company's customary paid time off policy ("CalTime").

         7.      Expenses.  During the term of this Employment Agreement, the
Company shall reimburse the Employee for all reasonable out-of- pocket expenses
incurred by the Employee in connection with the business of the Company and in
performance of his duties under this Employment Agreement upon the Employee's
presentation to the Company of an itemized accounting of such expenses with
reasonable supporting data.

         8.      Term.

                 (a)      The Employee's employment under this Employment
Agreement shall commence on the Effective Date and shall expire on the two year
anniversary date thereof.  Notwithstanding the foregoing, the Company may at
its election, terminate the Employee's employment hereunder as follows:



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                                             Initials:_________     _________

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                   (i)    Upon thirty (30) days notice if the Employee becomes
         physically or mentally incapacitated or is injured so that he is unable
         to perform the services required of him hereunder and such inability to
         perform continues for a period in excess of ninety (90) days and is
         continuing at the time of such notice; or

                   (ii)   For "Cause" upon notice of such termination to the
         Employee.  For purposes of this Employment Agreement, the Company shall
         have "Cause" to terminate its obligations hereunder upon (A) the
         reasonable determination by the Chief Executive Officer that the
         Employee has ceased to perform his duties hereunder (other than as a
         result of his incapacity due to physical or mental illness or injury),
         which failure amounts to an intentional and extended neglect of his
         duties hereunder, (B) the Chief Executive Officer's reasonable
         determination that the Employee has engaged or is about to engage in
         conduct materially injurious to the Company, (C) the Employee's having
         been convicted of a felony, or (D) A material breach by the Employee of
         any of the other covenants or representations herein; or

                 (iii)    (a) Without Cause (A)  if within the 90-day period
         following the effective date of a "Change in Control" (as defined
         below) of the Company, by paying to the Employee salary continuation
         pay equal to the Employee's base salary in effect at the time of
         termination for a period equal to the greater of (i) 12 months from the
         date of such termination or (ii) the remaining term of this Employment
         Agreement or (B) if at any time, by paying to the Employee salary
         continuation pay equal to the Employee's base salary in effect at the
         time of termination for the remaining term of this Employment
         Agreement. If the Company shall decide not to renew this Employment
         Agreement, the ninety (90) day notification of the Company's intention
         not to renew prior to expiration of the initial or any subsequent
         annual term shall serve as adequate termination notice and the Employee
         hereby agrees to make a smooth transition of responsibilities during
         that ninety (90) day period and the Employee further agrees not to take
         any legal action against the Company related to said non-renewal and
         termination of employment.;

                          (b)    In the event that the Employee resigns during 
         the 90-day period following the effective date of a Change of Control
         of the Company, the Employee shall receive salary continuation pay
         equal to the Employee's base salary in effect at the time of the Change
         in Control for the period of 12 months from the date of such
         termination.;





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                          (c)      For purposes of this Employment Agreement,
         "Change of Control" shall mean (a) an acquisition (other than directly
         from the Company) by an individual, entity or a group (excluding the
         Company, an employee benefit plan of the Company or E.M. Warburg,
         Pincus & Co., LLC or its affiliates) of 50% or more of the Company's
         Common Stock, par value $.01 per share, or voting securities; (b) a
         change in a majority of the Company's current Board of Directors (the
         "Incumbent Board") (excluding any persons approved by a vote of at
         least a majority of the Incumbent Board or persons elected with the
         concurrence of a majority of the Incumbent Board); or (c) the
         consummation of a complete liquidation or dissolution of the Company or
         a merger, consolidation or sale of all or substantially all of the
         Company's assets (collectively, a "Business Combination") other than a
         Business Combination in which all or substantially all of the Company's
         stockholders receive 50% of more of the stock of the Company resulting
         from the Business Combination, at least a majority of the board of
         directors of the resulting corporation were members of the Incumbent
         Board, and after which no Person owns 50% or more of the stock of the
         resulting corporation, who did not own such stock immediately before
         the Business Combination.; and

                          (d)      Not later than ninety (90) days prior to the
         expiration of the stated term of this Employment Agreement, the parties
         shall begin to negotiate in good faith the terms of any extension of
         this Employment Agreement, provided that neither party shall be under
         any obligation to enter into such an extension. In the case of a
         renewal and unless otherwise agreed to in writing by both parties, the
         terms and conditions of this Employment Agreement shall apply to any
         renewals or extensions thereto.

                 (iv)     Upon the death of the Employee.

         9.      Representations.  The Employee hereby represents to the
Company that (a) he is legally entitled to enter into this Employment Agreement
and to perform the services contemplated herein and is not bound under any
employment or consulting agreement to render services to any third party, (b)
he has the full right, power and authority, subject to no rights of third
parties, to grant to the Company the rights contemplated by paragraph 10
hereof, and (c) he does not now have, nor within the last three years has he
had, any ownership interest in any business enterprise (other than interest in
publicly traded corporations where his ownership does not exceed one percent
(1%) or more of



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the equity capital) which is a customer of the Company, any of its
subsidiaries, or from which the Company or any of its subsidiaries purchases
any goods or services or to whom such corporations owe any financial
obligations or are required or directed to make any payments.

         10.     Inventions.

                 (a)      The Employee hereby sells, transfers and assigns to
the Company or to any person, or entity designated by the Company all of the
entire right, title and interest of the Employee in and to all inventions,
ideas, disclosures and improvements, whether patented or unpatented, and
copyrightable material, made or conceived by the Employee, solely or jointly,
during the term hereof which relate to methods, apparatus, designs, products,
processes or devices, sold, leased, used or under consideration or development
by the Company or any of its subsidiaries, or which otherwise relate to or
pertain to the business, functions or operations of the Company or any of its
subsidiaries or which arise from the efforts of the Employee during the course
of his employment for the Company or any of its subsidiaries.  The Employee
shall communicate promptly and disclose to the Company, in such form as the
Company requests, all information, details and data pertaining to the
aforementioned inventions, ideas, disclosures and improvements; and the
Employee shall execute and deliver to the Company such formal transfers and
assignments and such other papers and documents as may be necessary or required
of the Employee to permit the Company or any person or entity designated by the
Company to file and prosecute the patent applications and, as to copyrightable
material, to obtain copyright thereof.  Any invention relating to the business
of the Company and its subsidiaries and disclosed by the Employee within one
year following the termination of this Agreement shall be deemed to fall within
the provisions of this paragraph unless proved to have been first conceived and
made following such termination.

                 (b)      The Employee has been notified and understands that
the provisions of this Section 11 do not apply to any of the aforementioned
inventions, ideas, disclosures and improvements that qualify fully under the
provisions of Section 2870 of the California Labor Code, which states as
follows:

                          (i)     Any provision in an employment agreement
which provides that an employee shall assign, or offer to assign, any of his or
her rights in an invention to his or her employer shall not apply to an
invention that the employee developed entirely on his or her own time without
using the employer's equipment, supplies, facilities, or trade secret
information except for those inventions that either:



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                                  (a)      Relate at the time of conception or
reduction to practice of the invention to the employer's business, or actual or
demonstrably anticipated research or development of the employer.

                                  (b)      Result from any work performed by
the employee for the employer.

                          (ii)    To the extent a provision in an employment
agreement purports to require an employee to assign an invention otherwise
excluded from being required to be assigned under subsection (i), the provision
is against the public policy of this state and is unenforceable.

         11.     Insurance.  The Company may, at its election and for its
benefit, insure the Employee against accidental loss or death, and the Employee
shall submit to such physical examination and supply such information as may be
required in connection therewith.

         12.     Notices.  Any notice required or permitted to be given under
this Employment Agreement shall be sufficient if in writing and if sent by
registered mail to Mr. Ben Matzilevich at his home address as reflected on the
records of the Company, in the case of the Employee, or Mr. Stelios B.
Papadopoulos, Chief Executive Officer, CN Biosciences, Inc., 10394 Pacific
Center Court, San Diego, CA 92121, in the case of the Company.

         13.     Waiver of Breach.  A waiver by the Company or the Employee of
a breach of any provision of this Employment Agreement by the other party shall
not operate or be construed as a waiver of any subsequent breach by the other
party.

         14.     Governing Law.  This Employment Agreement shall be governed by
and construed and enforce in accordance with the laws of the State of
California without giving effect to the choice of law or conflict of laws
provisions thereof.

         16.     Assignment.  This Employment Agreement may be assigned,
without the consent of the Employee, by the Company to any person, partnership,
corporation, or other entity which has purchased substantially all the assets
of the Company, provided such assignee assumes all the liabilities of the
Company hereunder.







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         17.     Entire Agreement.  This Employment Agreement contains the
entire agreement of the parties and supersedes any and all agreements, letter
of intent or understandings between the Employee and (a) the Company, (b) any
member of the Calbiochem Novabiochem Group or (c) any of the Company's
principal shareholders, affiliates or subsidiaries regarding employment.  This
Employment Agreement may be changed only by an agreement in writing signed by a
party against whom enforcement of any waiver, change, modification, extension
or discharge is sought.

         IN WITNESS WHEREOF, the parties have executed this Employment
Agreement as of the day first herein above written.


                                       CN BIOSCIENCES, INC.



                                       By:   /S/ STELIOS B. PAPADOPOULOS
                                          -----------------------------------
                                             Stelios B. Papadopoulos
                                             Chief Executive Officer


                                             EMPLOYEE



                                       By:   /S/ BEN MATZILEVICH
                                          -----------------------------------
                                             Ben Matzilevich






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