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                                                                   EXHIBIT 10.40

PAYMENT OF THIS NOTE IS SUBJECT TO THE TERMS AND CONDITIONS OF THAT CERTAIN
SETTLEMENT AGREEMENT, DATED AS OF FEBRUARY 13, 2002, BY AND AMONG MOLECULAR
DIAGNOSTICS, INC., A DELAWARE CORPORATION, PETER GOMBRICH, AN ILLINOIS RESIDENT,
AND SCHWARTZ, COOPER, GREENBERGER & KRAUSS, CHARTERED, AN ILLINOIS PROFESSIONAL
CORPORATION. THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES LAWS OF THE
UNITED STATES OR ANY OTHER JURISDICTION AND IS BEING OFFERED AND SOLD PURSUANT
TO AN EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT OF 1933
(THE "ACT") AND SUCH OTHER SECURITIES LAWS AS MAY BE APPLICABLE. ACCORDINGLY,
THIS NOTE MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE
ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT UNDER THE ACT OR AN OPINION OF
COUNSEL SATISFACTORY TO MOLECULAR DIAGNOSTICS, INC. THAT SUCH REGISTRATION IS
NOT REQUIRED.

                                 PROMISSORY NOTE

$118,500.00                                                    Chicago, Illinois
                                                               February 13, 2002

     FOR VALUE RECEIVED, MOLECULAR DIAGNOSTICS, INC., a Delaware corporation
("Maker"), hereby promises to pay to the order of SCHWARTZ, COOPER, GREENBERGER
& KRAUSS, CHARTERED, an Illinois professional corporation (hereinafter referred
to, individually, as "Payee," and, together with any other simultaneous or
successive lawful holders hereof, as the "Holder"), in lawful money of the
United States of America, the principal amount of ONE HUNDRED EIGHTEEN THOUSAND
FIVE HUNDRED AND NO/100 DOLLARS ($118,500.00), in the manner provided below.
This Note has been executed and delivered pursuant to and in accordance with the
terms and provisions of that certain Settlement Agreement, dated as of February
13, 2002 (the "Settlement Agreement"), by and among Maker, Payee and Peter
Gombrich ("Gombrich"), an Illinois resident and an officer and director of
Maker, the terms and conditions of which are, by this reference, incorporated
herein and made a part hereof. Capitalized terms used in this Note without
definition shall have the respective meanings given to them in the Settlement
Agreement.

     1. Payment of Principal. The principal amount of this Note shall be due and
payable on March 15, 2002 (the "Maturity Date"), in cash, in one (1) lump sum,
together with all interest accrued thereon.

     2. Interest. Interest shall be payable on the principal amount hereof from
time to time outstanding, such interest to accrue from the date hereof through
and including the date on which said principal amount has been paid in full, at
the rate of twelve percent (12%) per annum. All interest accrued hereon shall be
due and payable on the same date that the principal amount with respect to which
such interest was calculated becomes due and payable. Interest shall be computed
on the basis of a 365 day year, and payable for the actual number of days
elapsed.

     3. Manner of Payment. Unless otherwise agreed to in writing by the Holder,
all payments of principal and interest due under the terms and provisions of
this Note shall be made


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by wire transfer of immediately available funds to an account designated by the
Holder in writing. If any payment of such principal or interest is due on a day
that is not a Business Day (as defined below), such payment shall be due on the
next succeeding Business Day, and such extension of time shall be taken into
account in calculating the amount of interest payable on this Note. "Business
Day" shall mean any day other than a Saturday, Sunday or legal holiday in the
State of Illinois.

     4. Prepayment. Maker may prepay the principal balance of this Note in whole
or in part at any time and from time to time without prior notice, premium or
penalty.

     5. Security for Note; Guaranty.

          (a) This Note shall initially be unsecured, and shall remain unsecured
throughout its term unless Payee or any other Holder hereof shall give notice in
writing to Maker, at any time or from time to time during the term hereof, that
Payee or said Holder desires to have this Note secured, in which case, Maker
shall, within five (5) business days after receipt of such notice, provide Payee
or said Holder with the requested security, the value of which shall not exceed
one hundred fifty percent (150%) of the balance of principal and interest then
remaining payable under this Note; provided, however, that any such request for
security shall be reasonable in nature.

          (b) This Note, and the payment thereof, shall be personally guaranteed
in full by Gombrich under the terms and conditions of a separate written
Guaranty of even date herewith, which terms and conditions are incorporated
herein by this reference.

     6. Events of Default. (a) The occurrence and continuance of any one or more
of the following events shall constitute an event of default hereunder (an
"Event of Default"):

          (i) If Maker shall fail to pay, when due, any portion of the principal
or interest payable hereunder; or

          (ii) If, pursuant to or within the meaning of the United States
Bankruptcy Code or any other federal or state law relating to insolvency or
relief of debtors (a "Bankruptcy Law"), Maker shall (1) commence a voluntary
case or proceeding; (2) consent to the entry of an order for relief against it
in an involuntary case; (3) consent to the appointment of a trustee, receiver,
assignee, liquidator or similar official; (4) make an assignment for the benefit
of its creditors; or (5) admit in writing its inability to pay its debts as they
become due; or

          (iii) If a court of competent jurisdiction enters an order or decree
under any Bankruptcy Law that (1) is for relief against Maker in an involuntary
case; (2) appoints a trustee, receiver, assignee, liquidator or similar official
for Maker or substantially all of Maker's assets or properties; or (3) orders
the liquidation of Maker, and in each such case the order or decree is not
dismissed within sixty (60) days.

     (b) Upon the occurrence of an Event of Default hereunder (unless such Event
of Default has been waived by the Holder or cured), the Holder may, at the
Holder's sole option, (i) by written notice to Maker, declare the entire unpaid
principal balance of this Note, together with all interest accrued thereon,
immediately due and payable regardless of any prior forbearance,


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and (ii) exercise any and all rights or remedies available to the Holder under
applicable law, including, without limitation, the right to collect from Maker
all amounts due under this Note. In addition, upon the occurrence of such an
Event of Default, the number of shares of Common Stock, $.001 par value per
share, of Maker which Payee is entitled to acquire under the terms and
conditions of that certain Stock Purchase Warrant (the "Warrant"), dated
February 13, 2002 and issued by Maker to Payee pursuant to the terms and
conditions of the Settlement Agreement, shall be increased, from 750,000 to
1,500,000, as provided in the Warrant.

     7. Waiver. To the extent permitted by law, Maker hereby waives demand,
notice, protest and all other demands and notices in connection with the
delivery, acceptance, performance, default or enforcement of this Note. No
waiver by Payee or any other Holder hereof of any right or remedy under this
Note shall be effective unless in a writing signed by such waiving party.
Neither the failure nor any delay in exercising any right, power or privilege
under this Note will operate as a waiver of such right, power or privilege, and
no single or partial exercise of any such right, power or privilege by Payee or
any other Holder hereof shall preclude any other or further exercise of such
right, power or privilege or the exercise of any other right, power or
privilege.

     8. Severability. If any provision of this Note is held invalid or
unenforceable by any court of competent jurisdiction, then the other provisions
of this Note shall remain in full force and effect. Any provision of this Note
held invalid or unenforceable only in part or degree shall remain in full force
and effect to the extent not held invalid or unenforceable.

     9. Reimbursement. Maker shall reimburse each Holder hereof for any and all
costs and expenses, including, without limitation, actual attorney's fees,
incurred by such Holder in enforcing the rights of such Holder under this Note.
Such costs and expenses shall include, without limitation, costs and expenses
incurred by such Holder in any bankruptcy, reorganization, insolvency or other
similar proceeding.

     10. Governing Law. All questions concerning the construction, validity,
enforcement and interpretation of this Note shall be governed by the internal
laws of the State of Illinois, without giving effect to any choice of law or
conflict of law provision or rule (whether of the State of Illinois or any other
jurisdiction) that would cause the application of the laws of any jurisdiction
other than the State of Illinois. Maker hereby irrevocably submits to the
jurisdiction of the state and federal courts sitting in the City of Chicago, for
the adjudication of any dispute hereunder or in connection herewith or
contemplated hereby or discussed herein, and hereby irrevocably waives, and
agrees not to assert in any suit, action or proceeding, any claim that it is not
personally subject to the jurisdiction of any such court, that such suit, action
or proceeding is brought in an inconvenient forum or that the venue of such
suit, action or proceeding is improper. Maker hereby irrevocably waives personal
service of process and consents to process being served in any such suit, action
or proceeding by mailing a copy thereof to Maker and agrees that such service
shall constitute good and sufficient service of process and notice thereof.
Nothing contained herein shall be deemed to limit in any way any right to serve
process in any manner permitted by law. MAKER HEREBY IRREVOCABLY WAIVES ANY
RIGHT IT MAY HAVE TO, AND AGREES NOT TO REQUEST, A JURY TRIAL FOR THE
ADJUDICATION OF ANY DISPUTE HEREUNDER OR IN CONNECTION HEREWITH OR ARISING OUT
OF THIS NOTE OR ANY TRANSACTION CONTEMPLATED HEREBY.


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     11. Paragraph Headings; Construction. The paragraph headings contained in
this Note are provided for convenience only and shall not affect the
construction or interpretation of this Note. All words used in this Note shall
be construed to be of such gender or number as the circumstances require. Unless
otherwise expressly provided, the words "hereof" and "hereunder" and similar
references refer to this Note in its entirety and not to any specific paragraph
or subparagraph hereof.

     12. Binding Effect. The terms and conditions of this Note shall inure to
the benefit of, and be binding upon, Maker and Payee and any successors and
permitted assigns of either.

     13. Notices. Any notice or other communication required or permitted
hereunder shall be sufficiently given if it is in writing and either personally
served, sent by confirmed facsimile transmission, air courier guaranteeing next
business day delivery or certified or registered United States mail, postage
prepaid, and shall be deemed delivered upon receipt if personally served, or
upon confirmation of receipt if sent by facsimile transmission, or the next
business day, if sent by air courier guaranteeing next business day delivery,
or, if sent by mail, there (3) business days after deposit in the United States
mail with postage prepaid and properly addressed. For purposes hereof, the
addresses of the initial parties hereto shall be as follows:

         If to Maker, to:

         Molecular Diagnostics, Inc.
         414 North Orleans
         Suite 510
         Chicago, Illinois 60610
         Attention:     Peter P. Gombrich,
                        Chairman of the Board, President and
                        Chief Executive Officer
         Telecopier:    (312) 222-9580
         Confirmation:  (312) 222-9550

         If to Payee, to:

         Schwartz, Cooper, Greenberger & Krauss, Chartered
         180 North LaSalle Street
         Suite 2700
         Chicago, Illinois 60601
         Attention:     Richard J. Firfer, Esq.,
                        Edward S. Weil, Esq.
                        or Robert A. Smoller, Esq.
         Telecopier:    (312) 782-8416
         Confirmation:  (312) 346-1300

or to such other address as shall be furnished in writing by either party (or
their respective successors or permitted assigns) to the other in accordance
with the provisions of this Paragraph 13.



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     14. Lost or Stolen Note. Upon receipt by Maker of evidence satisfactory to
Maker of the loss, theft, destruction or mutilation of this (or any replacement)
Note, and upon the delivery of a written indemnification by the Holder to Maker
in a form reasonably acceptable to Maker and, in the case of mutilation, upon
surrender and cancellation of this Note, Maker shall execute and deliver to the
Holder a new Note of like tenor and date.

     15. Amendment. This Note and any provision hereof may only be amended by an
instrument in writing signed by Maker and the Holder. The term "Note" and all
references thereto, as used throughout this instrument, shall mean this
instrument as originally executed, or if later amended or supplemented, then as
so amended or supplemented.

     16. Remedies, Etc. The remedies provided in this Note shall be cumulative
and in addition to all other remedies available to Payee or any other Holder
hereof by law or under this Note (including a decree of specific performance
and/or other injunctive relief), together with any right of such party to bring
any action under any federal or state securities laws or for fraud, and no
remedy contained herein shall be deemed a waiver of compliance with the
provisions giving rise to such remedy, and nothing herein shall limit such
party's right to pursue actual damages for any failure by Maker to comply with
the terms of this Note. Maker covenants with Payee and any other Holder hereof
that there shall be no characterization concerning this instrument other than as
expressly provided herein. Amounts set forth or provided for herein with respect
to payments and the like (and the computation thereof) shall be the amounts to
be received by the Payee or such other Holder hereof and shall not, except as
expressly provided herein, be subject to any other obligation of Maker (or the
performance thereof). Maker acknowledges that a breach by Maker of its
obligations hereunder would cause irreparable harm to Payee and any other Holder
hereof and that the remedy at law for any such breach may be inadequate. Maker
therefore agrees that, in the event of any such breach or threatened breach, the
Payee and any other Holder hereof shall be entitled, in addition to all other
available remedies, to an injunction restraining any such breach, without the
necessity of showing economic loss and without any bond or other security being
required.





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     IN WITNESS WHEREOF, Maker has executed and delivered this Note as of the
date first hereinabove set forth, and Payee has acknowledged the terms hereof
and accepted delivery of this Note as of the same date.

                                       MOLECULAR DIAGNOSTICS, INC.,
                                       a Delaware corporation



                                       By:
                                          --------------------------------------
                                          Peter Gombrich, Chairman of the Board,
                                          President and Chief Executive Officer


Accepted and Agreed:

SCHWARTZ, COOPER, GREENBERGER
& KRAUSS, CHARTERED,
an Illinois professional corporation



By:
   ------------------------------------
         A Principal






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