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                                                                 Exhibit 4.3


                              [FORM OF GLOBAL NOTE]

                                                              CUSIP No.:

                                DADE BEHRING INC.

                      o% SENIOR SUBORDINATED NOTE DUE 2010

No.                                                           $

                  DADE BEHRING INC., a Delaware corporation (the "Company,"
which term includes any successor entity), for value received promises to pay to
       or registered assigns, the principal sum of                      Dollars,
on o, 2010.

                  Interest Payment Dates: o and o.

                  Record Dates: o and o.

                  Reference is made to the further provisions of this Note
contained herein, which will for all purposes have the same effect as if set
forth at this place.

                  IN WITNESS WHEREOF, the Company has caused this Note to be
signed manually or by facsimile by its duly authorized officers and a facsimile
of its corporate seal to be affixed hereto or imprinted hereon.

                                           DADE BEHRING INC.

                                           By: _________________________________
                                               Name:
                                               Title

                                           By: _________________________________
                                               Name:
                                               Title
Certificate of Authentication

                  This is one of the o% Senior Subordinated Notes due 2010
referred to in the within-mentioned Indenture.

                                           [TRUSTEE], as Trustee

Dated:                                     By: _________________________________
                                                     Authorized Signatory


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                              (REVERSE OF SECURITY)

                      o% SENIOR SUBORDINATED NOTE DUE 2010

                  1. INTEREST. DADE BEHRING INC., a Delaware corporation (the
"COMPANY"), promises to pay interest on the principal amount of this Note at the
rate per annum shown above (the "COUPON"). Interest on the Notes will accrue
from the most recent date on which interest has been paid or, if no interest has
been paid, from o, 2002. The Company will pay interest semi-annually in arrears
on each Interest Payment Date, commencing o, 2002. Interest will be computed on
the basis of a 360-day year of twelve 30-day months.

                  The Company shall pay interest on overdue principal and on
overdue installments of interest from time to time on demand at the rate borne
by the Notes plus 2% per annum and on overdue installments of interest (without
regard to any applicable grace periods) to the extent lawful.

                  2. METHOD OF PAYMENT. The Company shall pay interest on the
Notes (except defaulted interest) to the Persons who are the registered Holders
at the close of business on the Record Date immediately preceding the Interest
Payment Date even if the Notes are cancelled on registration of transfer or
registration of exchange after such Record Date. Holders must surrender Notes to
a Paying Agent to collect principal payments. The Company shall pay principal,
premium, if any, and interest at the corporate offices of the Paying Agent in
money of the United States that at the time of payment is legal tender for
payment of public and private debts ("U.S. LEGAL TENDER"). However, the Company
may pay interest by its check payable in such U.S. Legal Tender. The Company may
deliver any such interest payment to the Paying Agent or to a Holder at the
Holder's registered address.

                  3. PAYING AGENT AND REGISTRAR. Initially, Deutsche Bank
Company Americas, a New York banking corporation (the "TRUSTEE"), will act as
Paying Agent and Registrar. The Company may change any Paying Agent, Registrar
or co-Registrar without notice to the Holders.

                  4. INDENTURE. The Company issued the Notes under an Indenture,
dated as of o, 2002 (the "INDENTURE"), between the Company and the Trustee. This
Note is one of a duly authorized issue of Notes of the Company designated as its
o% Senior Subordinated Notes due 2010. The Notes are limited in aggregate
principal amount to $o. Capitalized terms herein are used as defined in the
Indenture unless otherwise defined herein. The terms of the Notes include those
stated in the Indenture and those made part of the Indenture by reference to the
Trust Indenture Act of 1939 (15 U.S. Code Sections 77aaa-77bbbb) (the "TIA"), as
in effect on the date of the Indenture. Notwithstanding anything to the contrary
herein, the Notes are subject to all such terms, and Holders of Notes are
referred to the Indenture and said Act for a statement of them. The Notes are
general unsecured obligations of the Company.

                  5. SUBORDINATION. The Notes are subordinated in right of
payment, in the manner and to the extent set forth in the Indenture, to the
prior payment in full in cash or Cash Equivalents of all Senior Debt of the
Company, whether outstanding on the date of the Indenture or thereafter created,
incurred, assumed or guaranteed. Each Holder by his acceptance hereof


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agrees to be bound by such provisions and authorizes and expressly directs the
Trustee, on his behalf, to take such action as may be necessary or appropriate
to effectuate the subordination provided for in the Indenture and appoints the
Trustee his attorney-in-fact for such purposes.

                  6. REDEMPTION.

                  (a) OPTIONAL REDEMPTION. The Notes will be redeemable, at the
Company's option, in whole at any time or in part from time to time, upon not
less than 30 nor more than 60 days' notice, as set forth below:

Redemption after ____________, 2005.

         On or after __________, 2005 the Notes will be subject to redemption at
the redemption prices (expressed as percentages of the principal amount thereof)
set forth below plus accrued and unpaid interest thereon to but not including
the applicable Redemption Date, if redeemed during the twelve-month period
beginning on [DATE] of the years indicated below:

<Table>
<Caption>
                       YEAR                               %                   PERCENTAGE
                       ----                               -                   ----------
<S>                                                  <C>            <C>

2005..............................................    __________%    [100% plus 1/2 of the Note
                                                                     Interest Rate]
2006..............................................    __________%    [100% plus 3/8 of the Note
                                                                     Interest Rate]
2007..............................................    __________%    [100% plus 1/4 of the Note
                                                                     Interest Rate]
2008..............................................    __________%    [100% plus 1/8 of the Note
                                                                     Interest Rate]
2009 and thereafter...............................     100.000%
</Table>

provided, however, that if the notice of redemption is mailed prior to an
Interest Payment Date but the Redemption Date falls after such Interest Payment
Date, then the applicable interest shall be paid on such Interest Payment Date
and the accrued and unpaid interest to the Redemption Date shall be that
interest accruing from such Interest Payment Date to the Redemption Date.

                  (b) OPTIONAL REDEMPTION UPON EQUITY OFFERINGS. At any time and
from time to time, prior to __________, 2005, the Company may redeem up to a
maximum of 35% of the original aggregate principal amount of the Notes with the
net cash proceeds of one or more Equity Offerings, at a Redemption Price equal
to 100% of the principal amount thereof, plus the Coupon, plus accrued and
unpaid interest thereon, if any, to the Redemption Date; provided, however, that
immediately after giving effect to any such redemption, at least 65% of the
original aggregate principal amount of the Notes remains outstanding. Any such
redemption shall be made within 75 days of such Equity Offering upon not less
than 30 nor more than 60 days' prior notice; provided, however, that if the
notice of redemption is mailed prior to an Interest Payment Date but the
Redemption Date falls after the same Interest Payment Date, then the applicable
interest shall be paid on the Interest Payment Date and the accrued and unpaid
interest to the Redemption Date shall be that interest accruing from the
Interest Payment Date to the Redemption Date.


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                  (c) MAKEWHOLE REDEMPTION. The Company may choose to redeem the
Notes at any time prior to _________, 2005 upon the terms and subject to the
conditions set forth in this paragraph. The Company may redeem all or any
portion of the Notes, at once or from time to time, after giving the required
notice under the Indenture. To redeem the Notes prior to ________, 2005, the
Company must pay a Redemption Price equal to the greater of:

                           (a) 100% of the principal amount of the Notes to be
redeemed, and

                           (b) the sum of the present values of (i) the
Redemption Price of the Notes at _______, 2005 (such Redemption Price being
___%) and (ii) any interest due on the Notes through _______ , 2005, in each
case discounted to the date of redemption on a semiannual basis (assuming a
360-day year consisting of twelve 30-day months) at the Makewhole Rate plus
0.50%, plus, in either case, accrued and unpaid interest, if any, to the
Redemption Date; provided, however, that if the notice of redemption is mailed
prior to an Interest Payment Date but the Redemption Date falls after such
Interest Payment Date, then the applicable interest shall be paid on such
Interest Payment Date and the accrued and unpaid interest to the Redemption Date
shall be that interest accruing from such Interest Payment Date to the
Redemption Date.

                  Any notice to Holders of Notes of such a redemption shall
include the appropriate calculation of the Redemption Price, but is not required
to include the Redemption Price itself. The actual Redemption Price, calculated
as described above, shall be set forth in an Officers' Certificate delivered to
the Trustee no later than two business days prior to the Redemption Date.

                  7. NOTICE OF REDEMPTION. Notice of redemption will be mailed
at least 30 days but not more than 60 days before the Redemption Date to each
Holder of Notes to be redeemed at such Holder's registered address. Notes in
denominations larger than $1,000 may be redeemed in part.

                  Except as set forth in the Indenture, if monies for the
redemption of the Notes called for redemption shall have been deposited with the
Paying Agent for redemption on such Redemption Date, then, unless the Company
defaults in the payment of such Redemption Price plus accrued interest, if any,
the Notes called for redemption will cease to bear interest from and after such
Redemption Date and the only right of the Holders of such Notes will be to
receive payment of the Redemption Price plus accrued interest, if any.

                  8. OFFERS TO PURCHASE. Sections 4.15 and 4.16 of the Indenture
provide that, after certain Asset Sales (as defined in the Indenture) and upon
the occurrence of a Change of Control (as defined in the Indenture), and subject
to further limitations contained therein, the Company will make an offer to
purchase certain amounts of the Notes in accordance with the procedures set
forth in the Indenture.

                  9. DENOMINATIONS; TRANSFER; EXCHANGE. The Notes are in
registered form, without coupons, in denominations of $1,000 and integral
multiples of $1,000. A Holder shall register the transfer of or exchange Notes
in accordance with the Indenture. The Registrar may require a Holder, among
other things, to furnish appropriate endorsements and transfer documents and to
pay certain transfer taxes or similar governmental charges payable in


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connection therewith as permitted by the Indenture. The Registrar need not
register the transfer of or exchange of any Notes or portions thereof selected
for redemption.

                  10. PERSONS DEEMED OWNERS. The registered Holder of a Note
shall be treated as the owner of it for all purposes.

                  11. UNCLAIMED MONEY. If money for the payment of principal or
interest remains unclaimed for two years, the Trustee and the Paying Agent will
pay the money back to the Company. After that, all liability of the Trustee and
such Paying Agent with respect to such money shall cease.

                  12. DISCHARGE PRIOR TO REDEMPTION OR MATURITY. If the Company
at any time deposits with the Trustee U.S. Legal Tender or U.S. Government
Obligations sufficient to pay the principal of and interest on the Notes to
redemption or maturity and complies with the other provisions of the Indenture
relating thereto, the Company will be discharged from certain provisions of the
Indenture and the Notes (including certain covenants, but excluding its
obligation to pay the principal of and interest on the Notes).

                  13. AMENDMENT; SUPPLEMENT; WAIVER. Subject to certain
exceptions, the Indenture or the Notes may be amended or supplemented with the
written consent of the Holders of at least a majority in aggregate principal
amount of the Notes then outstanding, and any existing Default or Event of
Default or noncompliance with any provision may be waived with the written
consent of the Holders of a majority in aggregate principal amount of the Notes
then outstanding. Without notice to or consent of any Holder, the parties
thereto may amend or supplement the Indenture or the Notes to, among other
things, cure any ambiguity, defect or inconsistency, provide for uncertificated
Notes in addition to or in place of certificated Notes, or comply with Article
Five of the Indenture or make any other change that does not adversely affect in
any material respect the rights of any Holder of a Note.

                  14. RESTRICTIVE COVENANTS. The Indenture imposes certain
limitations on the ability of the Company and its Restricted Subsidiaries to,
among other things, incur additional Indebtedness, make payments in respect of
its Capital Stock or certain Indebtedness, enter into transactions with
Affiliates, create dividend or other payment restrictions affecting
Subsidiaries, merge or consolidate with any other Person, sell, assign,
transfer, lease, convey or otherwise dispose of all or substantially all of its
assets or adopt a plan of liquidation. Such limitations are subject to a number
of important qualifications and exceptions. The Company must annually report to
the Trustee on compliance with such limitations.

                  15. SUCCESSORS. When a successor assumes, in accordance with
the Indenture, all the obligations of its predecessor under the Notes and the
Indenture, the predecessor will be released from those obligations.

                  16. DEFAULTS AND REMEDIES. If an Event of Default occurs and
is continuing, the Trustee or the Holders of at least 25% in aggregate principal
amount of Notes then outstanding may declare all the Notes to be due and payable
in the manner, at the time and with the effect provided in the Indenture.
Holders of Notes may not enforce the Indenture or the Notes except as provided
in the Indenture. The Trustee is not obligated to enforce the Indenture or the


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Notes unless it has received indemnity reasonably satisfactory to it. The
Indenture permits, subject to certain limitations therein provided, Holders of a
majority in aggregate principal amount of the Notes then outstanding to direct
the Trustee in its exercise of any trust or power. The Trustee may withhold from
Holders of Notes notice of any continuing Default or Event of Default (except a
Default in payment of principal or interest) if it determines that withholding
notice is in their interest.

                  17. TRUSTEE DEALINGS WITH COMPANY. The Trustee under the
Indenture, in its individual or any other capacity, may become the owner or
pledgee of Notes and may otherwise deal with the Company, its Subsidiaries or
their respective Affiliates as if it were not the Trustee.

                  18. NO RECOURSE AGAINST OTHERS. No stockholder, director,
officer, employee or incorporator, as such, of the Company shall have any
liability for any obligation of the Company under the Notes or the Indenture or
for any claim based on, in respect of or by reason of, such obligations or their
creation. Each Holder of a Note by accepting a Note waives and releases all such
liability. The waiver and release are part of the consideration for the issuance
of the Notes.

                  19. AUTHENTICATION. This Note shall not be valid until the
Trustee or Authenticating Agent manually signs the certificate of authentication
on this Note.

                  20. GOVERNING LAW. The Laws of the State of New York shall
govern this Note and the Indenture, without regard to principles of conflict of
laws.

                  21. ABBREVIATIONS AND DEFINED TERMS. Customary abbreviations
may be used in the name of a Holder of a Note or an assignee, such as: TEN CON
(= tenants in common), TEN ENT (= tenants by the entireties), .JT TEN (= joint
tenants with right of survivorship and not as tenants in common), CUST (=
Custodian), and U/G/M/A (= Uniform Gifts to Minors Act).

                  22. CUSIP NUMBERS. Pursuant to a recommendation promulgated by
the Committee on Uniform Security Identification Procedures, the Company has
caused CUSIP numbers to be printed on the Notes as a convenience to the Holders
of the Notes. No representation is made as to the accuracy of such numbers as
printed on the Notes and reliance may be placed only on the other identification
numbers printed hereon.

                  23. INDENTURE. Each Holder, by accepting a Note, agrees to be
bound by all of the terms and provisions of the Indenture, as the same may be
amended from time to time.

                  The Company will furnish to any Holder of a Note upon written
request and without charge a copy of the Indenture, which has the text of this
Note in larger type. Requests may be made to: Dade Behring Inc., 1717 Deerfield
Road, Deerfield, IL 60015-0778, Attn: Chief Financial Officer.


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                                 ASSIGNMENT FORM

                  If you the Holder want to assign this Note, fill in the form
below and have your signature guaranteed:

I or we assign and transfer this Note to:

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________
        (Print or type name, address and zip code and social security or
                           tax ID number of assignee)

and irrevocably appoint _______________________________________, agent to
transfer this Note on the books of the Company. The agent may substitute another
to act for him.

Dated: ____________________         Signed: ____________________________________
                                            (Sign exactly as name appears on the
                                            other side of this Note)

 Signature Guarantee:  _________________________________________________________


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                      [OPTION OF HOLDER TO ELECT PURCHASE)

                  If you want to elect to have this Note purchased by the
Company pursuant to Section 4.15 or Section 4.16 of the Indenture, check the
appropriate box:

                  Section 4.15 [      ]
                  Section 4.16 [      ]

                  If you want to elect to have only part of this Note purchased
by the Company pursuant to Section 4.15 or Section 4.16 of the Indenture, state
the amount you elect to have purchased:

$________________________

Dated: ________________________        _________________________________________
                                       NOTICE: The signature on this assignment
                                               must correspond with the name as
                                               it appears upon the face of the
                                               within Note in every particular
                                               without alteration or
                                               enlargement or any change
                                               whatsoever and be guaranteed by
                                               the endorser's bank or broker.

Signature Guarantee: _____________________________


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