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EXHIBIT *(10.37)
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THE OBLIGATIONS EVIDENCED HEREBY ARE SUBORDINATE IN THE MANNER AND TO THE EXTENT
SET FORTH IN THAT CERTAIN SUBORDINATION AGREEMENT (THE "SUBORDINATION AGREEMENT")
DATED AS OF OCTOBER 29, 1999, AMONG FLEET CAPITAL CORPORATION, AMERICAN CAPITAL
STRATEGIES, LTD., IGI, INC., IGEN, INC., IMMUNOGENETICS, INC., AND BLOOD CELLS,
 INC., TO THE INDEBTEDNESS AND OTHER LIABILITIES OWED BY IGI, INC., IGEN, INC.,
 IMMUNOGENETICS, INC., AND BLOOD CELLS, INC. UNDER AND PURSUANT TO THE LOAN AND
    SECURITY AGREEMENT DATED AS OF OCTOBER 29, 1999, AND EACH RELATED "LOAN
   DOCUMENT" (AS DEFINED THEREIN), AND EACH HOLDER HEREOF, BY ITS ACCEPTANCE
      HEREOF, ACKNOWLEDGES AND AGREES TO BE BOUND BY THE PROVISIONS OF THE
                            SUBORDINATION AGREEMENT.

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       IGI, INC., IGEN, INC., IMMUNOGENETICS, INC., AND BLOOD CELLS, INC.
            SERIES B SENIOR SUBORDINATED NOTE DUE SEPTEMBER 30, 2006

No. SSN - 1                                                   October 29, 1999
$350,000

         FOR VALUE RECEIVED, the undersigned IGI, INC., a Delaware corporation,
("IGI"), IGEN, INC., a Delaware corporation ("Igen"), IMMUNOGENETICS, INC., a
Delaware corporation, ("ImmunoGenetics"), and BLOOD CELLS, INC., a Delaware
corporation ("Blood Cells") (IGI, Igen, ImmunoGenetics and Blood Cells are
referred to herein as the "Loan Parties"), hereby promise to pay to AMERICAN
CAPITAL STRATEGIES, LTD., or registered assigns (the "Holder"), the principal
sum of THREE HUNDRED FIFTY THOUSAND DOLLARS ($350,000), with interest thereon,
on the terms and conditions set forth in the Purchase Agreement (as defined
herein).

         Payments of principal of, interest on and any premium with respect to
this Georgia Note are to be made in lawful money of the United States of America
by check mailed and addressed to the registered Holder hereof at the address
shown in the register maintained by the Loan Parties for such purpose, or, at
the option of the Holder, in such manner and at such other place in the United
States of America as the Holder hereof shall have designated to the Loan Parties
in writing.

         Notwithstanding any provision to the contrary in this Georgia Note, the
Purchase Agreement or any other agreement, the Loan Parties shall not be
required to pay, and the Holder shall not be permitted to contract for, take,
reserve, charge or receive, any compensation which constitutes interest under
applicable law in excess of the maximum amount of interest permitted by law.

         This Georgia Note is one of a series of Series B Senior Subordinated
Notes Due September 30, 2006 (herein called the "Georgia Notes") issued pursuant
to the Note and Equity Purchase Agreement, dated as of October 29, 1999 (as from
time to time amended, the "Purchase Agreement"), between the Loan Parties and
American Capital Strategies, Ltd., a corporation organized and existing under
the laws of the State of
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Delaware, and is entitled to the benefits thereof. All terms used herein shall
have the meanings ascribed to them in the Purchase Agreement. Each Holder of
this Georgia Note will be deemed, by its acceptance hereof, to have agreed to
the provisions and to have made the representations and warranties set forth in
Article 6 of the Purchase Agreement.

         The Georgia Notes are issuable as registered notes. This Georgia Note
is transferable only by surrender hereof at the principal office of the Loan
Parties at Wheat Road and Lincoln Avenue, Buena (Atlantic County), New Jersey,
duly endorsed or accompanied by a written instrument of transfer duly executed
by the registered Holder of this Georgia Note.

         This Georgia Note is also subject to optional prepayment, in whole or
in part at the times and on the terms specified in the Purchase Agreement, but
not otherwise.

         If an Event of Default as defined in the Purchase Agreement occurs and
is continuing, the unpaid principal of this Georgia Note may be declared or
otherwise become due and payable in the manner, at the price (including any
applicable premium) and with the effect provided in the Purchase Agreement.

         Payments of principal, interest on and any premium with respect to this
Georgia Note are secured pursuant to the terms of the Security Documents.

         This Note and the rights and obligations of the parties hereto shall be
deemed to be contracts under the laws of the State of Maryland and for all
purposes shall be governed by and construed and enforced in accordance with the
laws of said State, except for its rules relating to the conflict of laws.

                                        IGI, INC.



                                        By: /s/ Paul Woitach
                                           ------------------------------------
                                            Name: Paul Woitach
                                            Title: President


                                        IGEN, INC.



                                        By: /s/ Paul Woitach
                                           ------------------------------------
                                            Name: Paul Woitach
                                            Title: President



                                        IMMUNOGENETICS, INC.
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                                        By: /s/ Paul Woitach
                                            ____________________________________
                                            Name:  Paul Woitach
                                            Title: President


                                        BLOOD CELLS, INC.



                                        By: /s/ Paul Woitach
                                            ____________________________________
                                            Name:  Paul Woitach
                                            Title: President