EMPLOYMENT AGREEMENT



PARTIES:

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

                  Thomas R. Witty, Ph.D.                    (the "Employee")
                  3414 Kenilworth Lane
                  Santa Cruz, California  96065

DATE:             October 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 Vice President -
Research and Development of the Company until such time as the Company or

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Employee decides to 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 Employer and agrees to
perform such reasonable services and duties as may, from time to time, be
assigned to him by the Chief Executive Officer, President or Chief Operating
Officer of the Company relating to the research and development of the Company's
products. While employee is employed by the Company, Employee will not perform
services for any other person, firm or corporation, either as an employee or as
an agent or other independent contractor without the express consent of the
Chief Executive Officer of the Company. Employee agrees to comply in ever
respect with the general standards and policies of the Company as in effect from
time to time during Employee's employment, all of which Employer reserves the
right to change in its sole discretion.

 3.  Compensation.

                  A. Base Salary. The Company shall pay Employee an initial
annual salary of $125,000 (the "Base Salary"), payable in accordance with the
Company's normal payroll practices in effect from time to time beginning as of
the date this Agreement. The Employee's compensation shall be subject to
discretionary upward adjustments by the Company's Chief Executive Officer.

                  B. Bonus. The Company shall establish a bonus plan consistent
with Company policy whereby Employee shall be entitle to receive bonuses in cash
and/or securities of the Company as determined by the Company's Board of
Directors or its compensation committee.

4.       Other Employee Benefits.

                  A. Benefits. For so long as Employee remains employed by the
Company, Employer agrees to obtain and maintain for the benefit of Employee,
health insurance benefits of the same nature as the Company maintains from time
to time in favor of its employees in general and to provide such other benefits
as the Company announces from time to time to apply to its employees in general.

                  B. Rental Car, Housing and Plane fare. Until such time as
Employee's permanent residence is within a reasonable commute by automobile to
a Company facility, the Company will reimburse Employee for his rental car
expense, accommodation rental expense and plane fare for himself, and once a
month for a companion, to the Company.

                  C. Reimbursement of Expenses. The Company will reimburse
Employee for all of Employees out-of-pocket expenses related to Company
business, provided, however, that any such single expense in excess of $500 will
be approved by the Company's Chief Operating Officer.

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                  D. Vacation. Employee shall be entitled to three (3) weeks of
vacation each year.

                  E. Options. Employee will be provided a five year
non-qualified stock option to purchase up to 300,000 shares of Quantech Common
Stock at $.25 per share which option shall fully-vest over a two year term
(100,000 shares immediately, 100,000 shares after one year of employment and
100,000 shares after two years of employment) and contain such other general
terms as those provided other Quantech employees.

5.       Termination of Employment.

                  Employee shall not be entitled to any payments upon
termination of employment, except any salary or 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
six (6) month's base salary 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 Common Stock pursuant to a single transaction or
a series of transactions by the same acquiring party.

6.  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
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.

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                  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 G. Freitag, COO

                                     "Employee"


                                     ____________________________
                                     Thomas R. Witty, Ph.D.






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