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EXHIBIT *(10.24)               TERM LOAN B NOTE

$350,000.00                                                     October 29, 1999

      FOR VALUE RECEIVED, and intending to be legally bound, the undersigned,
IGI, INC., IGEN, INC., IMMUNOGENETICS, INC., and BLOOD CELLS, INC., each a
Delaware corporation (collectively, "Borrowers," and severally, each a
"Borrower") promises to pay to the order of FLEET CAPITAL CORPORATION
("Lender"), in such coin or currency of the United States which shall be legal
tender in payment of all debts and dues, public and private, at the time of
payment, the principal sum of Three Hundred Fifty Thousand Dollars
($350,000.00), together with interest from and after the date hereof on the
unpaid principal balance outstanding at the applicable rates per annum set forth
in the Loan Agreement (as defined below). Interest shall be computed in the
manner provided in Section 2 of the Loan Agreement.

      This Term Loan B Note (the "Note") is the Term Loan B Note referred to in,
and is issued pursuant to, that certain Loan and Security Agreement between
Borrowers and Lender dated the date hereof (as amended from time to time, the
"Loan Agreement"), and is entitled to all of the benefits and security of the
Loan Agreement. All of the terms, covenants and conditions of the Loan Agreement
and the Security Documents are hereby made a part of this Note and are deemed
incorporated herein in full. All capitalized terms used herein, unless otherwise
specifically defined in this Note, shall have the meanings ascribed to them in
the Loan Agreement.

      The principal amount and accrued interest of this Note shall be due and
payable on the dates and in the manner hereinafter set forth:

            (a) Interest shall be due and payable in arrears, on the first day
      of each month, commencing on the first day of the first month following
      the date hereof, and continuing until such time as the full principal
      balance, together with all other amounts owing hereunder, shall have been
      paid in full.

            (b) The entire principal amount then outstanding, together with any
      and all other unpaid amounts hereunder, shall be due and payable on the
      Revolving Credit Maturity Date.

      Notwithstanding the foregoing, the entire unpaid principal balance and
accrued interest on this Note shall be due and payable immediately upon the
earlier of acceleration of the Obligations following an Event of Default under
the Loan Agreement or termination of the Loan Agreement pursuant to Section 4
thereof.

      This Note shall be subject to mandatory prepayment (and prepayment
premium, if applicable) in accordance with the provisions of Section 3.3 of the
Loan Agreement. Borrower may also terminate the Loan Agreement and, in
connection with such termination, prepay this Note in the manner provided in
Section 4 of the Loan Agreement.

      Upon the occurrence of an Event of Default, Lender shall have all of the
rights and remedies set forth in Section 10 of the Loan Agreement or as
available at law or in equity to protect and enforce Lender's rights hereunder.

      Time is of the essence of this Note. To the fullest extent permitted by
applicable law, each Borrower, for itself and its legal representatives,
successors and assigns, expressly waives presentment,


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demand, protest, notice of dishonor, notice of non-payment, notice of maturity,
notice of protest, presentment for the purpose of accelerating maturity, and
diligence in collection.

      Wherever possible, each provision of this Note shall be interpreted in
such manner as to be effective and valid under applicable law, but if any
provision of this Note shall be prohibited or invalid under applicable law, such
provision shall be ineffective to the extent of such prohibition or invalidity
without invalidating the remainder of such provision or remaining provisions of
this Note. No delay or failure on the part of Lender in the exercise of any
right or remedy hereunder shall operate as a waiver thereof, nor as an
acquiescence in any default, nor shall any single or partial exercise by Lender
of any right or remedy preclude any other right or remedy. Lender, at its
option, may enforce its rights against any Collateral securing this Note without
enforcing its rights against Borrowers (or any one or more of them) or any other
property of any Borrower. Each Borrower agrees that, without releasing or
impairing Borrowers' liability hereunder, Lender may at any time release,
surrender, substitute or exchange any Collateral securing this Note and may at
any time release any party primarily or secondarily liable for the indebtedness
evidenced by this Note.

       IN ANY LITIGATION ARISING OUT OF OR RELATING TO ANY OF THE MATTERS
CONTAINED IN THIS NOTE OR ANY OF THE DOCUMENTS DELIVERED IN CONNECTION HEREWITH
IN WHICH LENDER AND BORROWER ARE ADVERSE PARTIES, LENDER AND EACH BORROWER WAIVE
TRIAL BY JURY.

      This Note shall be governed by, and construed and enforced in accordance
with, the laws of the State of Pennsylvania. All obligations of Borrowers
hereunder shall be joint and several.


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      IN WITNESS WHEREOF, Borrowers have caused this Note to be duly executed
and delivered on the date first above written.

                                    IGI, INC.
Attest:

/s/ Robert McDaniel                 By: /s/ Manfred Hanuschek
----------------------------            --------------------------------------
                                    Name:  Manfred Hanuschek
                                           -----------------------------------
                                    Title: CFO
                                           -----------------------------------

                                    IGEN, INC.
Attest:

/s/ Robert McDaniel                 By: /s/ Manfred Hanuschek
----------------------------            --------------------------------------
                                    Name:  Manfred Hanuschek
                                           -----------------------------------
                                    Title: CFO
                                           -----------------------------------

                                    IMMUNOGENETICS, INC.
Attest:

/s/ Robert McDaniel                 By: /s/ Manfred Hanuschek
----------------------------            --------------------------------------
                                    Name:  Manfred Hanuschek
                                           -----------------------------------
                                    Title: CFO
                                           -----------------------------------

                                    BLOOD CELLS, INC.
Attest:

/s/ Robert McDaniel                 By: /s/ Manfred Hanuschek
----------------------------            --------------------------------------
                                    Name:  Manfred Hanuschek
                                           -----------------------------------
                                    Title: CFO
                                           -----------------------------------


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