Exhibit 10.1

                     SECOND AMENDMENT TO LICENSE AGREEMENTS


Effective Date:  December 7, 1999

PARTIES:

Quantech, Ltd.                                       (herein called "Quantech")
a Minnesota corporation
1419 Energy Park Drive
Saint Paul, Minnesota  55108


The Perkin-Elmer Corporation                              (herein called "PE")
a New York Corporation
for its PE Biosystems Division
761 Main Avenue
Norwalk, Connecticut  06589-0001

RECITALS:

A. Quantech and PE are parties to (i) a certain agreement with an effective date
of 16 December, 1997, as amended by the Amendment to License Agreements dated
November 4, 1999 (the "Quantech License Agreement"), pursuant to which, among
other things, Quantech granted to PE a license under the Serono Technology and
Quantech Intellectual Property, and (ii) the Perkin Elmer/Quantech License
Agreement with an effective date of 29 June 1998, as amended by the Amendment to
License Agreements dated November 4, 1999, pursuant to which, among other
things, PE granted a license to certain PE technology described in a patent
application entitled "Surface Plasmon Array System" (the "PE License
Agreement").

B. The parties are shareholders of NEWCO, a Minnesota corporation.

C. The parties desire to amend the Quantech License Agreement and the PE License
Agreement as hereinafter set forth, and, for and in consideration of the mutual
promises set forth herein, and for other good and valuable consideration, the
receipt of which is hereby acknowledged, the parties hereby agree as follows:

1.       DEFINITIONS

1.1      Capitalized terms not defined herein shall have the definitions set
         forth in the Quantech License Agreement, or, in sections of this
         Agreement that amend the PE License Agreement, set forth in the PE
         License Agreement.

                                       1
<PAGE>

1.2      "Agreements" means the Quantech License Agreement and the PE License
         Agreement.

2.       AGREEMENT TO SUBLICENSE. Quantech agrees that PE may sublicense any and
         all rights under the Quantech License Agreement to NEWCO.

3.       AMENDMENTS TO AGREEMENTS. The Agreements are hereby amended as follows:

         3.1 The parties acknowledge that no PE Intellectual Property arose from
         a joint development effort with Quantech pursuant to Section 3.1 of the
         Quantech License Agreement, and that Sections 3.1, 3.2 and 4.2 of the
         Quantech License Agreement will only be applicable in the event PE
         receives back from Newco any of the rights sublicensed by PE to Newco
         pursuant to the Perkin Elmer/Newco License and Sublicense Agreement.

         3.2 Sections 5.1 and 5.3 of the Quantech License Agreement are deleted
         in their entirety, so that, among other things, no minimum royalties
         will be required from PE.

         3.3 Section 5.4 of the Quantech License Agreement will be replaced in
         its entirety by the following:

                  "Status Reports. If PE or Newco as its Sublicensee shall not
                  have begun selling Licensed Products by March 31, 2001, on or
                  before the forty fifth (45th) day after the end of each
                  Calendar Quarter beginning with the calendar quarter ending
                  June 30, 2001, PE or the Sublicensee shall deliver to Quantech
                  a Statement of Intent signed by a duly authorized employee of
                  PE or the Sublicensee stating that PE or the Sublicensee is
                  continuing to pursue research and development efforts with an
                  intent to commercialize, or is continuing commercialization
                  of, Licensed Products. The obligation to provide such
                  quarterly Statements of Intent shall terminate upon the
                  earlier of the sale of the first Licensed Product or payment
                  of first royalty payment under Section 5.2. If PE or the
                  Sublicensee shall fail to timely deliver a Statement of
                  Intent, Quantech may notify PE and the Sublicensee of this
                  failure. If PE or the Sublicensee fails to deliver the
                  Statement of Intent within two months of Quantech's notice,
                  PE's license and the Sublicensee's sublicense rights granted
                  in Section 2 shall immediately terminate".

         3.4 Section 5.2(a) of the Quantech License Agreement is amended by
         inserting the following words at the beginning of the first sentence of
         Section 5.2(a), "In the event that the sublicense agreement of even
         date herewith between PE and Newco is terminated,".

                                       2

<PAGE>

         3.5 Section 5.2(b) of the Quantech License Agreement is amended by
         inserting the following words at the beginning of the first sentence of
         Section 5.2(b), "In the event that the sublicense agreement of even
         date herewith between PE and Newco is terminated".

         3.6 Section 3.1 of the PE License Agreement is deleted in its entirety.

         3.7 Section 4.2 of the PE License is deleted in its entirety so that no
         minimum royalties will be required from Quantech, effective the date of
         this Second Amendment to License Agreement.

4.       AGREEMENTS OTHERWISE IN FULL FORCE AND EFFECT.

Except as expressly set forth in this Amendment, the Agreements shall remain in
full force and effect in accordance with their terms.

IN WITNESS WHEREOF, each of the parties has caused this agreement to be executed
in the manner appropriate to each, effective as of the date first above written

Quantech, Ltd.                                 The Perkin-Elmer Corporation


By:____________________________                By:_____________________________
     Robert Case, CEO
                                               Name:___________________________

                                               Title:__________________________


                                       3