EMPLOYMENT AGREEMENT



PARTIES:

                  Quantech Ltd.                               (the "Company")
                  1419 Energy Park Drive
                  St. Paul, Minnesota  55108

                  Robert Case                                 (the "Employee")
                  640 N LaSalle St.
                  Chicago, 60610

DATE:             December 1, 1997

RECITALS:

                  A. The Company is engaged in the  business of  developing  and
commercializing  certain patents,  technology,  associated  proprietary data and
existing operating  prototypes related to medical diagnostics based upon Surface
Plasmon Resonance.

                  B. The Employee seeks to be employed, and the Company seeks to
employ, Employee under the terms of this Agreement.

                  C. The Employee  agrees that as a condition to employment with
the Company the Employee will abide by the terms of this Agreement.

                  D. The  Employee  desires to be  employed  by the Company in a
capacity in which he may contribute to, or receive confidential information, and
acknowledges  that the Company  will suffer  irreparable  harm if Employee  uses
confidential  information  outside  his  employment  or makes  any  unauthorized
disclosure  of such  confidential  information  to any third  party or uses such
confidential information wrongfully or in competition with the Company.

                  E. Employee   further   recognizes   that  execution  of  this
Agreement is an express condition of employment.

AGREEMENTS:

                  NOW, THEREFORE, in consideration of the mutual promises herein
contained,  and  other  benefits  now or  hereafter  paid or made  available  to
Employee by the Company, the parties hereby agree as follows:

1.  Employment at Will. The Company hereby employs  Employee as Chief  Executive
Officer of the Company  until such time as the  Company or  Employee  decides to

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terminate Employee's employment. Nothing in this Agreement shall be construed to
create an employment relationship other than one that is at will or constituting
a commitment,  guaranty,  agreement, or understanding of any kind or nature that
Quantech shall continue to employ Employee,  nor shall this letter affect in any
way the right of Quantech to terminate Employee's employment at any time and for
any reason.

2. Duties and Supervision. During the term of this Agreement, Employee agrees to
devote  best  efforts to the  business  and affairs of the Company and agrees to
perform  such  reasonable  services  and  duties as may,  from time to time,  be
assigned  to him by the  Board  of  Directors.  The  Company  acknowledges  that
Employee  shall not  devote  full time to the  affairs of the  Company  and will
perform services for other persons, firms and corporations.

3. Employee Benefits.  The Company  will reimburse Employee for all of Employees
out-of-pocket expenses related to the Company business.

4. Payments Upon Termination  Employment.  Employee shall not be entitled to any
payments upon termination of employment, except any bonuses that have accrued to
Employee through the date of such termination shall be paid by the Company,  and
further  provided that Employee shall also be entitled to a lump-sum  payment of
$150,000 if termination of Employment is a result of a sale of substantially all
of the assets of the  Company or a change in the control of more than 50% of the
Company's  Capital  Stock  pursuant  to a  single  transaction  or a  series  of
transactions by the same acquiring party.

5.  General Provisions.

                  A. Injunctive Relief. In addition to any other relief afforded
by law, the Company shall have the right to enforce the  covenants  contained in
this  Agreement  by seeking  injunctive  relief  against  Employee and any other
person concerned  thereby,  it being understood that both damages and injunctive
relief  shall  be  proper  modes  of  relief  and  are not to be  considered  as
alternative remedies.

                  B.  Severability  and  Interpretation.  In  the  event  that a
provision   of  this   Agreement  is  held  invalid  by  a  court  of  competent
jurisdiction,   the  remaining   provisions  shall  nonetheless  be  enforceable
according to their terms. Further, in the event that any provision is held to be
overbroad  as  written,  such  provision  shall be deemed  amended to narrow its
application to the extent necessary to make the provision  enforceable according
to applicable law and shall be enforced as amended.

                  C. Entire  Agreement.  This Agreement  constitutes  the entire
agreement  between the parties and  supersedes any and all prior oral or written
understandings between the parties relating to the subject matter hereof, except
for the Confidentiality and Invention Agreement entered into between the Company
and Employee of even date with this Agreement.

                  D.   Modification   and  Waiver.   No   purported   amendment,
modification or waiver of any provision hereof shall be binding unless set forth
in a  written  document  signed by all  parties  (in the case of  amendments  or

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modifications)  or by the party to be charged  thereby (in the case of waivers).
Any waiver shall be limited to the provisions  hereof and the  circumstances  or
event specifically made subject thereto, and shall not be deemed a waiver of any
other term  hereof or of the same  circumstance  or event upon any  reoccurrence
thereof.

                  E.  Assignment.  This Agreement shall be binding on Employee's
heirs,  assigns  and legal representatives and may be transferred by the Company
to its successors and assigns.

                  F.  Governing Law.  This Agreement is governed by and shall be
construed in accordance with the laws of the State of Minnesota.

                  G.  Arbitration.  All  disputes  arising  under this Agreement
shall  be submitted for arbitration in the state of Minnesota, the United States
of America.

                  IN WITNESS  WHEREOF,  the parties  hereto have  executed  this
Agreement the day and year first above written.

                                    "Company"
                                    QUANTECH LTD.

                                    ----------------------------
                                    Gregory Freitag, COO & CFO

                                    "Employee"


                                    ----------------------------
                                    Robert Case, CEO