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                                                                    EXHIBIT 10.3



                                AMENDMENT NO. 1
                                       TO
                          AGREEMENT AND PLAN OF MERGER
                                  BY AND AMONG
                          ACCUMED INTERNATIONAL, INC.,
                            ACCUMED ACQUISITION CORP.
                                       AND
                          AMPERSAND MEDICAL CORPORATION


        THIS AMENDMENT NO. 1 is made and entered into as of the 10th day of May,
2001, by and among AccuMed International, Inc., a Delaware corporation
("AccuMed"), AccuMed Acquisition Corp., a Delaware corporation ("Acquisition
Sub"), and Ampersand Medical Corporation ("Ampersand").

                                   WITNESSETH:

        WHEREAS, the parties hereto have heretofore entered into that certain
Agreement and Plan of Merger dated as of February 7, 2001 (the "Merger
Agreement"), pursuant to which AccuMed will be merged with and into Acquisition
Sub and thereby become a wholly-owned subsidiary of Ampersand; and

        WHEREAS, the parties hereto have determined that it would be in their
respective best interests to modify and amend certain terms and provisions of
the Merger Agreement, and the directors of each of the parties hereto have
unanimously approved such modifications and amendments and directed the
respective officers of the parties to give effect to such changes;

        NOW, THEREFORE, in consideration of the mutual promises and agreements
herein contained, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledge, the parties hereto hereby agree as
follows:

1.             Closing Date; Termination Date.

               (a) The last sentence of Section 1.11 of the Merger Agreement is
hereby amended to change the date set forth therein from "May 31, 2001" to "July
31, 2001."

               (b) The tenth and thirteenth lines of Section 4.4 (a)(iii), the
eighth, ninth, eighteenth and nineteenth lines of Section 4.4(a)(iv), the second
line of Section 4.4(a)(v), and the fourth line of Section 5.5, of the Merger
Agreement are each hereby amended to change the dates set forth therein from
"May 31, 2001" to "July 31, 2001."

               (c) In the event that the Registration Statement has not become
effective on or prior to June 17, 2001, then all references in the Merger
Agreement to "July 31, 2001" shall automatically, without further action by the
parties hereto, be amended to "September 30, 2001," such amendment to become
effective as of June 17, 2001.

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               2. Ampersand Loan Obligations. The first sentence of Section
1.12(b) of the Merger Agreement is hereby deleted in its entirety and replaced
by the following:

               "Ampersand and AccuMed also hereby agree that if by February 28,
        2001 the Merger and the transactions contemplated hereby have not been
        consummated, then Ampersand shall loan additional monies (the
        "Additional Loans") to AccuMed as and when needed by AccuMed for use in
        its ordinary and usual business operations on the same terms and
        conditions as the Full Loan, except that:

               (i) simultaneously with the making of each Additional Loan, the
        collateral securing the Full Loan under the Security Agreement shall be
        increased in accordance with the terms of the Security Agreement in
        order to secure such Additional Loan as well, and AccuMed shall issue
        and deliver to Ampersand a new promissory note, substantially in the
        form of the Replacement Note, evidencing such Additional Loan;

               (ii) such Additional Loans shall be made on the first day of each
        month through and including the month in which the Merger and the
        transactions contemplated hereby are consummated or the month in which
        this Agreement is terminated in accordance with the provisions hereof,
        whichever comes first;

               (iii) the Additional Loans to be made on March 1, 2001 and April
        1, 2001 shall be made automatically, without any request therefor being
        necessary, and each shall be in the amount of Two Hundred Twenty-Five
        Thousand Dollars ($225,000);

               (iv) the Additional Loan to be made on May 1, 2001 shall be made
        automatically, without any request therefor being necessary, and shall
        be in the amount of One Hundred Fifty Thousand Dollars ($150,000);

               (v) the Additional Loans to be made on June 1, 2001 and the first
        day of each month thereafter until the Merger closes or the Merger
        Agreement is terminated, shall be made automatically, without any
        request therefor being necessary, in the amount of One Hundred Thousand
        Dollars ($100,000); provided, however, that upon the written request of
        AccuMed, delivered to Ampersand in accordance with the provisions hereof
        no less than two (2) business days prior to the last day of the month
        immediately preceding the scheduled payment date of the Additional Loan,
        each such Additional Loan shall have added to it such amount as AccuMed
        shall request in the aforesaid notice, so long as: (1) the total amount
        of the Additional Loan made on the relevant date does not exceed Two
        Hundred Twenty-Five Thousand Dollars ($225,000), and (2) said notice
        sets forth the specific business uses to which such added amount shall
        be put, which uses shall be reasonably satisfactory to Ampersand in
        order to obligate Ampersand to loan such added amount to AccuMed
        hereunder; and



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               (vi) prior to the making of each Additional Loan, AccuMed and
        Ampersand shall identify on a schedule or schedules to be attached to
        the Security Agreement sufficient additional collateral to secure such
        Additional Loans in accordance with the terms and conditions of the
        Security Agreement."

        3. Defined Terms. All capitalized terms not defined herein shall have
the meanings ascribed to them in the Merger Agreement.

        4. Continuing Effect of Original Agreement; Effective Date of Changes.
Except for the modifications and amendments specifically set forth herein, the
Merger Agreement shall continue in full force and effect as originally written.
Subject to the provisions of Section 1(c) of this Amendment, the modifications
and amendments set forth herein shall become immediately effective as of the
date first hereinabove set forth.

        5. Governing Law. This Amendment shall be governed by and construed in
accordance with the laws of the State of Illinois, without taking into account
any provisions regarding choice of law.

        IN WITNESS WHEREOF, each party has hereto caused this Agreement to be
executed on its behalf by its duly authorized officer as of the date first
hereinabove set forth.

ACCUMED INTERNATIONAL, INC                   AMPERSAND MEDICAL CORPORATION



By:    /s/ PAUL F. LAVALLEE                  By:   /s/ PETER P. GOMBRICH
    -------------------------------              -------------------------------
        Paul F. Lavallee,                           Peter P. Gombrich,
        Chairman of the Board and                   Chairman of the Board and
        Chief Executive Officer                     Chief Executive Officer

                                             ACCUMED ACQUISITION CORP.



                                             By:   /s/ PETER P. GOMBRICH
                                                 -------------------------------
                                                    Peter P. Gombrich, President



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