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                                                                    EXHIBIT 4.1


                          CERTIFICATE OF INCORPORATION

                                       OF

                          ACCUMED INTERNATIONAL, INC.


         FIRST.  The name of the corporation is: AccuMed International, Inc.
(the "Corporation").

         SECOND. The address of the Corporation's registered office in the
State of Delaware is 1209 Orange Street, in the City of Wilmington, County of
Newcastle (the "Registered Office").  The name of its registered agent at such
address is The Corporation Trust Company.

         THIRD.  The purpose of the Corporation is to engage in any lawful act
or activity for which a corporation may be organized under the General
Corporation Law of the State of Delaware as set forth in Title 8 of the
Delaware Code (the "GCL").

         FOURTH. The total number of shares of all classes of capital stock
which the Corporation shall have authority to issue is 35,000,000 shares,
divided into two classes as follows:

                  5,000,000 shares of Preferred Stock of the par value of $0.01
                  per share ("Preferred Stock"); and

                  30,000,000 shares of Common Stock of the par value of $0.01
                  per share ("Common Stock").

         The designations, powers, preferences and rights, and the
qualifications, limitations or restrictions of the above classes of stock are
as follows:

                                   DIVISION I

                                PREFERRED STOCK

         1.      The board of directors is expressly authorized at any time,
and from time to time, to issue shares of Preferred Stock in one or more
series, and for such





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consideration as the board of directors may determine, with such voting powers,
full or limited but not to exceed one vote per share, or without voting powers,
and with such designations, preferences and relative, participating, optional
or other special rights, and qualifications, limitations or restrictions
thereof, as shall be stated in the resolution or resolutions providing for the
issue thereof, and as are not stated in this Certificate of Incorporation, or
any amendment thereto.  All shares of any one series shall be of equal rank and
identical in all respects.

         2.      No dividend shall be paid or declared on any particular series
of Preferred Stock unless dividends shall be paid or declared pro rata on all
shares of Preferred Stock at the time outstanding of each other series which
ranks equally as to dividends with such particular series.

         3.      Unless and except to the extent otherwise required by law or
provided in the resolution or resolutions of the board of directors creating
any series of Preferred Stock pursuant to this Division I, the holders of the
Preferred Stock shall have no voting power with respect to any matter
whatsoever.  In no event shall the Preferred Stock be entitled to more than one
vote in respect of each share of stock.  Subject to the protective conditions
or restrictions of any outstanding series of Preferred Stock, any amendment to
this Certificate of Incorporation which shall increase or decrease the
authorized capital stock of any class or classes may be adopted by the
affirmative vote of the holders of a majority of the outstanding shares of the
voting stock of the Corporation.

         4.      Shares of Preferred Stock redeemed, converted, exchanged,
purchased, retired or surrendered to the Corporation, or which have been issued
and reacquired in any manner, shall, upon compliance with any applicable
provisions of the GCL, have the status of authorized and unissued shares of
Preferred Stock and may be reissued by the board of directors as part of the
series of which they were originally a part or may be reclassified into and
reissued as part of a new series or as a part of any other series, all subject
to the protective conditions or restrictions of any outstanding series of
Preferred Stock.

                                  DIVISION II

                                  COMMON STOCK

         1.      DIVIDENDS.  Subject to the preferential dividend rights, if
any, applicable to shares of the Preferred Stock and subject to applicable
requirements, if any, with respect to the setting aside of sums for purchase,
retirement or sinking funds for the




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Preferred Stock, the holders of the Common Stock shall be entitled to receive
to the extent permitted by law, such dividends as may be declared from time to
time by the board of directors.

         2.      LIQUIDATION.  In the event of the voluntary or involuntary
liquidation, dissolution, distribution of assets or winding up of the
Corporation, after distribution in full of the preferential amounts, if any, to
be distributed to the holders of shares of the Preferred Stock, holders of the
Common Stock shall be entitled to receive all the remaining assets of the
Corporation of whatever kind available for distribution to stockholders ratably
in proportion to the number of shares of Common Stock held by them
respectively.

         3.      VOTING RIGHTS.  Except as may be otherwise required by law or
this Certificate of Incorporation, each holder of the Common Stock shall have
one vote in respect of each share of stock held by him or her of record on the
books of the Corporation on all matters voted upon by the stockholders.



                                  DIVISION III

                           ELIMINATION OF PREEMPTIVE
                                     RIGHTS

         No holder of stock of any class of the Corporation shall be entitled
as a matter of right to purchase or subscribe for any part of any unissued
stock of any class, or of any additional stock of any class or capital stock of
the Corporation, or of any bonds, certificates of indebtedness, debentures, or
other securities convertible into stock of the Corporation, now or hereafter
authorized, but any such stock or other securities convertible into stock may
be issued and disposed of pursuant to resolution by the board of directors to
such persons, firms, corporations or associations and upon such terms and for
such consideration (not less than the par value or stated value thereof) as the
board of directors in the exercise of its discretion may determine and as may
be permitted by law without action by the stockholders.

         FIFTH.  The name and mailing address of the incorporator are as
follows: Roger R. Fross,  115 South LaSalle Street, Chicago, IL 60603.

         SIXTH.  The following provisions are inserted for the management of
the business and the conduct of the affairs of the Corporation, and for further
definition, limitation and regulation of the powers of the Corporation and of
its directors and stockholders:





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         (1)  The business and affairs of the Corporation shall be managed by
or under the direction of the board of directors.

         (2)  The directors shall have concurrent power with the stockholders
to make, alter, amend, change, add to or repeal the by-laws of the Corporation.

         (3)  The number of directors of the Corporation shall be as from time
to time fixed by, or in the manner provided in, the by-laws of the Corporation.
Election of directors need not be by written ballot unless the by-laws so
provide.

         (4)  No director shall be personally liable to the Corporation or any
of its stockholders for monetary damages for breach of fiduciary duty as a
director, except for liability (i) for any breach of the director's duty of
loyalty to the Corporation or its stockholders, (ii) for acts or omissions not
in good faith or which involve intentional misconduct or a knowing violation of
law, (iii) pursuant to Section 174 of the GCL or (iv) for any transaction from
which the director derived an improper personal benefit.  If the GCL is amended
to authorize corporate action further eliminating or limiting the personal
liability of directors, then the liability of a director of the Corporation
shall be eliminated or limited to the fullest extent permitted by the GCL as so
amended.  Any repeal or modification of this Article SIXTH by the stockholders
of the Corporation shall not adversely affect any right or protection of a
director of the Corporation existing at the time of such repeal or modification
with respect to acts or omissions occurring prior to such repeal or
modification.

         (5)   In addition to the powers and authority hereinbefore or by
statute expressly conferred upon them, the directors are hereby empowered to
exercise all such powers and do all such acts and things as may be exercised or
done by the Corporation, subject, nevertheless, to the provisions of the GCL,
this Certificate of Incorporation, and any by-laws adopted by the stockholders;
provided, however, that no by-laws adopted by the stockholders shall invalidate
any prior act of the directors which would have been valid if such by-laws had
not been adopted.

         SEVENTH.         Meetings of stockholders may be held within or
without the State of Delaware, as the by-laws may provide.  The books of the
Corporation may be kept (subject to any provision contained in the GCL) outside
the State of Delaware at such place or places as may be designated from time to
time by the board of directors or in the by-laws of the Corporation.

         EIGHTH. (1)  The Corporation shall indemnify any person who was or is
a party or is threatened to be made a party to any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative
or investigative





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(other than an action by or in the right of the Corporation) by reason of the
fact that he or she is or was a director or officer of the Corporation or is or
was serving at the request of the Corporation as a director, officer, employee
or agent of another corporation, partnership, joint venture, trust or other
enterprise, against expenses (including attorneys' fees), judgments, fines and
amounts paid in settlement actually and reasonably incurred by him or her in
connection with such action, suit or proceeding if he or she acted in good
faith and in a manner he or she reasonably believed to be in or not opposed to
the best interests of the Corporation, and, with respect to any criminal action
or proceeding, had no reasonable cause to believe his or her conduct was
unlawful.  The termination of any action, suit or proceeding by judgment,
order, settlement, conviction, or upon a plea of nolo contendere or its
equivalent, shall not, of itself, create a presumption that the person did not
act in good faith and in a manner which he or she reasonably believed to be in
or not opposed to the best interests of the Corporation, and, with respect to
any criminal action or proceeding, had reasonable cause to believe that his or
her conduct was unlawful.

         (2)  The Corporation shall indemnify any person who was or is a party
or is threatened to be made a party to any threatened, pending or completed
action or suit by or in the right of the Corporation to procure a judgment in
its favor by reason of the fact that he or she is or was a director or officer
of the Corporation, or is or was serving at the request of the Corporation as a
director, officer, employee or agent of another corporation, partnership, joint
venture, trust or other enterprise against expenses (including attorneys' fees)
and amounts paid in settlement actually and reasonably incurred by him or her
in connection with the defense or settlement of such action or suit if he or
she acted in good faith and in a manner he or she reasonably believed to be in
or not opposed to the best interests of the Corporation and except that no such
indemnification shall be made in respect of any claim, issue or matter as to
which such person shall have been adjudged to be liable to the Corporation
unless and only to the extent that the Court of Chancery of the State of
Delaware or the court in which such action or suit was brought shall determine
upon application that despite the adjudication of liability but in view of all
the circumstances of the case, such person is fairly and reasonably entitled to
indemnity for such expenses which the Court of Chancery of the State of
Delaware or such other court shall deem proper.

         (3)  To the extent that any person referred to in paragraphs (1) and
(2) of this Article EIGHTH has been successful on the merits or otherwise in
defense of any action, suit or proceeding referred to therein or in defense of
any claim, issue or matter therein, he or she shall be indemnified against
expenses (including attorneys' fees) actually and reasonably incurred by him or
her in connection therewith.





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         (4)  Any indemnification under paragraphs (1) and (2) of this Article
EIGHTH (unless ordered by a court) shall be made by the Corporation only as
authorized in the specific case upon a determination that indemnification of
the director or officer is proper in the circumstances because he or she has
met the applicable standard of conduct set forth in said paragraphs (1) and
(2).  Such determination shall be made (a) by a majority vote of the directors
who are not parties to such action, suit or proceeding, even though less than a
quorum, or (b) if there are no such directors, or if such directors so direct,
by independent legal counsel in a written opinion, or (c) by the stockholders.

         (5)  Expenses (including attorneys' fees) incurred by an officer or
director in defending any civil, criminal, administrative or investigative
action, suit or proceeding may be paid by the Corporation in advance of the
final disposition of such action, suit or proceeding upon receipt of an
undertaking by or on behalf of the director or officer to repay such amount if
it shall ultimately be determined that he or she is not entitled to be
indemnified by the Corporation as provided in this Article EIGHTH.

         (6)  The Corporation may, to the extent authorized from time to time
by the board of directors, grant rights to indemnification and to the
advancement of expenses, to any employee or agent of the Corporation or its
subsidiaries, or to any employee or agent of any entity providing contractual
services for the Corporation or its subsidiaries, to the fullest extent of the
provisions of this Article EIGHTH with respect to the indemnification and
advancement of expenses of directors and officers of the Corporation.

         (7)  The indemnification and advancement of expenses provided by or
granted pursuant to the other subsections of this Article EIGHTH shall not be
deemed exclusive of any other rights to which those seeking indemnification or
advancement of expenses may be entitled under any statute, by-law, agreement,
vote of stockholders or disinterested directors or otherwise, both as to action
in his or her official capacity and as to action in another capacity while
holding such office.

         (8)  The Corporation shall have power to purchase and maintain
insurance on behalf of any person who is or was a director, officer, employee
or agent of the Corporation, or is or was serving at the request of the
Corporation as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise against any liability
asserted against him or her and incurred by him or her in any such capacity, or
arising out of his or her status as such, whether or not the Corporation would
have the power to indemnify him or her against such liability under the
provisions of this Article.





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         (9)  For the purposes of this Article EIGHTH, references to the
"Corporation" shall include in addition to the resulting Corporation, any
constituent corporation (including any constituent of a constituent) absorbed
in a consolidation or merger which, if its separate existence had continued,
would have had power and authority to indemnify its directors, officers, and
employees or agents, so that any person who is or was a director, officer,
employee or agent of such constituent corporation, or is or was serving at the
request of such constituent corporation as a director, officer, employee or
agent of another corporation, partnership, joint venture, trust or other
enterprise, shall stand in the same position under the provisions of this
Article EIGHTH with respect to the resulting or surviving corporation as he or
she would have with respect to such constituent corporation if its separate
existence had continued.

         (10)  For purposes of this Article EIGHTH, references to "other
enterprises" shall include employee benefit plans; references to "fines" shall
include any excise taxes assessed on a person with respect to any employee
benefit plan; and references to "serving at the request of the Corporation"
shall include any service as a director, officer, employee or agent of the
Corporation which imposes duties on, or involves services by, such director,
officer, employee or agent with respect to an employee benefit plan, its
participants or beneficiaries; and a person who acted in good faith and in a
manner he or she reasonably believed to be in the interest of the participants
and beneficiaries of an employee benefit plan shall be deemed to have acted in
a manner "not opposed to the best interests of the Corporation" as referred to
in this paragraph.

         (11)  The indemnification and advancement of expenses provided by, or
granted pursuant to this Article EIGHTH shall, unless otherwise provided when
authorized or ratified, continue as to a person who has ceased to be a
director, officer, employee or agent and shall inure to the benefit of the
heirs, executors, and administrators of such a person.  Any repeal or
modification of this Article EIGHTH shall not adversely affect any right to
indemnification or advancement of expenses of any present or former director,
officer, employee or agent of the Corporation existing at the time of such
repeal or modification.

         (12)  If this Article EIGHTH or any portion hereof is invalidated by
any court of competent jurisdiction, then the Corporation shall nevertheless
provide such indemnification and advancement of expenses as would otherwise be
permitted under any portion of this Article EIGHTH that shall not have been
invalidated.

         NINTH.  Whenever a compromise or arrangement is proposed between this
Corporation and its creditors or any class of them and/or between this
Corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the





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State of Delaware may, on the application in a summary way of this Corporation
or of any creditor or stockholder thereof, or on the application of any
receiver or receivers appointed for this Corporation under the provisions of
Section 291 of the GCL or on the application of trustees in dissolution or of
any receiver or receivers appointed for this Corporation under the provisions
of Section 279 of the GCL, order a meeting of the creditors or class of
creditors, and/or of the stockholders or class of stockholders of this
Corporation, as the case may be, to be summoned in such manner as the said
court directs.  If a majority in number representing three-fourths in value of
the creditors or class of creditors, and/or the stockholders or class of
stockholders of this Corporation, as the case may be, agree to any compromise
or arrangement and to any reorganization of this Corporation as consequence of
such compromise or arrangement, the said compromise or arrangement and the said
reorganization shall, if sanctioned by the court to which the said application
has been made, be binding on all the creditors or class of creditors, and/or on
all the stockholders or class of stockholders, of this Corporation, as the case
may be, and also on this Corporation.

         TENTH.  The Corporation reserves the right to amend, alter, change or
repeal any provision contained in this Certificate of Incorporation, in the
manner now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation.

         I, the undersigned, being the sole incorporator hereinbefore named,
for the purpose of forming a Corporation pursuant to the GCL, do make this
certificate, hereby declaring and certifying that the facts herein stated are
true and accordingly have hereunto set my hand this 8th day of December, 1995.



                                         /s/ ROGER FROSS
                                         Incorporator





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