<PAGE>   1
                                                                EXHIBIT *(10.57)


                                 AMENDMENT NO. 1
                                     TO THE
                       NOTE AND EQUITY PURCHASE AGREEMENT

                                      AMONG

                   IGI, INC., IGEN, INC., IMMUNOGENETICS, INC.
                              AND BLOOD CELLS, INC.

                                       AND

                        AMERICAN CAPITAL STRATEGIES, LTD.
                                       AND
                     ACS FUNDING TRUST I, AS THE PURCHASERS
















                  AMENDMENT NO. 1 DATED AS OF : MARCH 30, 2000
                         ORIGINAL DATE: OCTOBER 29, 1999
<PAGE>   2
                                 AMENDMENT NO. 1
                                     TO THE
                       NOTE AND EQUITY PURCHASE AGREEMENT

                    $6,650,000 AGGREGATE PRINCIPAL AMOUNT OF
            SERIES A SENIOR SUBORDINATED NOTES DUE SEPTEMBER 30, 2006
                               OF THE LOAN PARTIES

                     $350,000 AGGREGATE PRINCIPAL AMOUNT OF
            SERIES B SENIOR SUBORDINATED NOTES DUE SEPTEMBER 30, 2006
                               OF THE LOAN PARTIES


         THIS AMENDMENT NO. 1 TO THE NOTE AND EQUITY PURCHASE AGREEMENT (this
"Amendment"), entered into as of March 30, 2000, is by and among 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 collectively referred to herein as the "Loan Parties"), and
AMERICAN CAPITAL STRATEGIES, LTD., a Delaware corporation ("ACAS"), and ACS
FUNDING TRUST I, a Delaware business trust (the "Trust" and with ACAS, the
"Purchaser").


                                    RECITALS

A.       The Loan Parties and ACAS entered into a Note and Equity Purchase
Agreement, dated as of October 29, 1999 (the "Agreement"), pursuant to which
ACAS purchased (i) from the Loan Parties certain Series A and Series B Senior
Subordinated Notes Due September 30, 2006 (collectively, the "Notes") and (ii) a
warrant for the purchase of 1,907,543 shares (as adjusted from time to time in
accordance with the terms thereof) of the Common Stock of IGI (the "Warrant").
As of October 29, 1999, ACAS sold or contributed the Notes to the Trust.

B.       The Loan Parties have requested that ACAS exercise its rights under the
Warrant, waive certain defaults under the Agreement and amend certain provisions
of the Agreement, and ACAS is willing to do so, on the terms and conditions set
forth herein.

C.       Capitalized terms used herein and not otherwise defined shall have the
meaning assigned to such term as set forth in the Agreement.

         NOW, THEREFORE, the parties hereto, in consideration of the premises
and their mutual covenants and agreements herein set forth and intending to be
legally bound hereby, covenant and agree as follows:
<PAGE>   3
                                   ARTICLE 1

                                   THE WAIVER

         1.1   Waiver of Defaults. Pursuant to Section 12.2 of the Agreement,
and upon satisfaction of the conditions set forth in Article 4 herein:

               a.  The Purchaser hereby waives any violation of Section 7.3(a)
of the Agreement which may have arisen in connection with the Loan Parties
having a Fixed Charges Coverage Ratio of .14 to 1.0 for the calendar quarter
ending December 31, 1999, and the Purchaser hereby further waives any Event of
Default resulting therefrom.

               b.  The Purchaser hereby waives any violation of Section
7.3(c) of the Agreement which may have arisen or which may arise in connection
with the Loan Parties having a Maximum Debt to Equity Ratio of greater than 4.25
to 1.0 for the calendar quarters ended December 31, 1999 and March 31, 2000, and
the Purchaser hereby further waives any Event of Default resulting therefrom.

               c.  The Purchaser hereby waives any Event of Default arising
under Section 8.1(b) of the Agreement in connection with any violation by any
Loan Party of any term, condition or provision of the Senior Credit Agreement to
the extent, but only to the extent, that any such violation has been waived by
the lenders thereunder pursuant to the terms thereof.

                                    ARTICLE 2
                                  THE AMENDMENT

         2.1   Amendment to Section 1.1, Definitions. Section 1.1 of the
Agreement is hereby amended as follows:


               a.  The terms "Put Option", "Put Option Closing", "Put Price"
and "Put Shares" shall be deleted in their entirety from the Agreement.

               b.  The term "Fixed Charges Coverage Ratio" shall be amended by
deleting it in its entirety and inserting in its place the following:

               "Fixed Charges Coverage Ratio" shall mean the ratio of (i)
               EBITDA less the unfinanced portion of Capital Expenditures to
               (ii) the sum of principal and interest payments made during
               the Measurement Period in respect of Indebtedness (other than
               any non-cash charges relating to the issuance of the Warrants
               pursuant to this Agreement or any requirement that the
               Warrants be marked to market).

               c.  The term "Market Price" shall be amended by deleting
it in its entirety and inserting in its place the following:

               "Market Price" of any security shall mean the average of the
               closing prices of such security's sales on all securities
               exchanges on which such security


                                       -2-
<PAGE>   4
               may at the time be listed, or, if there has been no sales on
               any such exchange on any day, the average of the highest bid
               and lowest asked prices on all such exchanges at the end of
               each day, or, if on any day such security is not so listed,
               the average of the representative bid and asked prices quoted
               in the NASDAQ System as of 4:00 P.M., New York time, or, if on
               any day such security is not quoted in the NASDAQ System, the
               average of the highest bid and lowest asked prices on such day
               in the domestic over-the-counter market as reported by the
               National Quotation Bureau, Incorporated, or any similar
               successor organization, in each such case averaged over a
               period of thirty (30) days consisting of the day as of which
               "Market Price" is being determined and the twenty-nine (29)
               consecutive business days prior to such day.

               d.  The term "Maximum Debt to Equity Ratio" shall be amended by
deleting it in its entirety and inserting in its place the following:

               "Maximum Debt to Equity Ratio" shall mean the ratio of total
               liabilities (other than any liabilities relating to the
               issuance of Warrants pursuant to this Agreement) to
               stockholders equity, provided that the Warrants shall be
               treated as equity for the purposes of calculating stockholders
               equity.

               e.  The following terms shall be inserted into Section 1.1 of the
Agreement:

              "Make-Whole Amount" shall have the meaning assigned to such term
in Section 9.1 hereof.

              "Make-Whole Trigger Event" shall have the meaning assigned to
such term in Section 9.1 hereof.

               "Shares" shall mean all shares of Common Stock of IGI received by
ACAS upon the exercise of the Warrant or acquired by ACAS pursuant to Section
3.1 hereof.

               "Shelf Registration Statement" shall mean the shelf registration
statement filed by IGI with the SEC with respect to resales of the Shares.

         2.2  Amendment to Section 3.1, Interest Rates and Interest Payments.
Section 3.1 of the Agreement is hereby modified and amended by deleting it in
its entirety and inserting in its place the following:

              3.1   Interest Rates and Interest Payments. The Notes will bear
              interest on the outstanding principal amount thereof at a fixed
              rate of fourteen and one-half percent (14.5%) per annum, 12.5% of
              which shall be payable in cash by the Loan Parties and 2.0% of
              which shall be capitalized on the Interest Payment Date and added
              to the principal of the Notes (such capitalized interest being
              hereinafter referred to as "Capitalized Interest").


                                      -3-
<PAGE>   5
              The Loan Parties shall make payments of interest due hereunder for
              the following periods on the following dates (each such date being
              an "Interest Payment Date"):

                     Period                               Date
                     ------                               ----
                     April 1, 2000 to July 31, 2000       July 31, 2000
                     August 1, 2000 to October 31, 2000   October 31, 2000
                     Thereafter                           At the end of
                                                          each three-month
                                                          period ending on
                                                          January 31, April 30,
                                                          July 31 and October 31

              On the Interest Payment Date occurring in October of each year,
              the Loan Parties shall issue to each holder of a Note a note
              substantially in the form attached hereto as Exhibit A in the
              amount of the Capitalized Interest accrued in respect of such
              Note; provided that the Loan Parties may, on such Interest Payment
              Date, at their election, in lieu of issuing such note, pay such
              Capitalized Interest in cash or deliver shares of Common Stock
              having an aggregate Market Price equal to such Capitalized
              Interest; and provided further that all unpaid Capitalized
              Interest payable upon the maturity of the Notes, together with all
              interest accrued thereon, shall be paid in cash by the Loan
              Parties. Notwithstanding the foregoing, during the period from
              April 1, 2000 until the earlier of (i) March 31, 2001 and (ii) the
              maturity of the Notes (whether as a result of the acceleration
              thereof pursuant to Section 8.2 hereof or otherwise), the Notes
              will bear interest on the outstanding principal amount thereof at
              a fixed rate of fourteen and three-fourths percent (14.75%) per
              annum, 12.5% of which shall be payable in cash by the Loan Parties
              and 2.25% of which shall constitute Capitalized Interest. Interest
              on the Notes will be computed on the basis of a year of 360 days,
              composed of twelve 30-day months, and the actual number of days
              elapsed.

         2.3  Amendment to Section 7.3(a), Financial Covenants, Minimum Fixed
Charges Coverage Ratio. Section 7.3(a) is hereby deleted in its entirety and
replaced with the following:

              (a) Minimum Fixed Charges Coverage Ratio. A Minimum Fixed Charges
              Coverage Ratio, for the applicable Measurement Date, of not less
              than:

<TABLE>
<CAPTION>
                   Period                                                   Ratio
                   ------                                                   -----
<S>                                                                     <C>
                   For the six-month period ending on 3-31-2000           .40 to 1.0
                   For the seven-month period ending on 4-30-2000         .45 to 1.0
                   For the eight-month period ending on 5-31-2000         .50 to 1.0
                   For the nine-month period ending on 6-30-2000          .50 to 1.0
</TABLE>


                                      -4-
<PAGE>   6
<TABLE>
<S>                                                                     <C>
                   For the ten-month period ending on 7-31-2000           .65 to 1.0
                   For the eleven-month period ending on 8-31-2000        .65 to 1.0
                   For the twelve-month period ending on 9-30-2000        .75 to 1.0
                   For the twelve-month period ending on 10-31-2000
                   (and thereafter as of the end of each month on a
                   rolling twelve-month basis)                           1.01 to 1.0
</TABLE>

         2.4  Amendment to Article 9, PUT OPTION. Article 9 of the Agreement is
hereby deleted in its entirety and replaced with the following:

                                    ARTICLE 9

                              MAKE-WHOLE FOR SHARES

         9.1  Sale of Shares; Make-Whole for Shares. (i) If, at any time after
the earliest to occur of (i) the fifth anniversary of the Closing Date, (ii) the
date of the payment in full of the outstanding principal, interest and fees of
the Notes, (iii) the date of the payment in full of the outstanding principal,
interest and fees of the Senior Debt, or (iv) the sale of IGI or of at least 30%
of its assets as part of a single transaction or series of related transactions
(unless Purchaser has granted IGI a waiver permitting such sale), (collectively,
the "Make-Whole Trigger Events"), Purchaser intends to sell any of the Shares,
it shall provide IGI written notice (the "Purchaser Notice") of such intention
and of the number of Shares proposed to be sold. IGI shall notify Purchaser in
writing, within three (3) Business Days of receipt by IGI of the Purchaser
Notice, of whether IGI intends to purchase such Shares (the "IGI Notice"). If
IGI elects to purchase such Shares from Purchaser, IGI shall exercise such
purchase right by paying Purchaser, within five (5) Business Days after it
provides the IGI Notice, in cash, against receipt of the Shares proposed to be
sold, the product of (x) the number of Shares proposed to be sold, multiplied by
(y) the Market Price per share on the date of the Purchaser Notice. If Purchaser
gives the Purchaser Notice and IGI does not exercise the purchase right
described in this Section 9.1(i), then Purchaser may sell the Shares in a market
transaction, a privately negotiated transaction or otherwise (a) after the
earlier of (I) expiration of the three-day period referred to in this Section
9.1(i) or (II) Purchaser's receipt of notice from IGI that it does not intend to
exercise the purchase right and (b) within 180 days of the date of the Purchaser
Notice.

               (ii)     If Purchaser sells any Shares pursuant to Section
9.1, IGI shall, within three (3) Business Days of receiving notice of any such
sale, pay the Purchaser an amount (the "Make-Whole Amount") equal to the product
of (x) the number of Shares sold by Purchaser during such 180-day period in
arm's length transactions multiplied by (y) the excess, if any, of (i) the
Market Price on the date of the Purchaser Notice over (ii) the price per share
at which Purchaser actually sold such Shares, plus any and all reasonable
expenses actually incurred by Purchaser in consummating such sale, in cash or
Common Stock of IGI, at IGI's election.

               (iii)    If Purchaser does not sell any of the Shares pursuant
to this Section 9.1 or if the Purchaser has sold only a portion of its Shares,
the provisions of this Section 9.1


                                      -5-
<PAGE>   7
shall continue to be in force with respect to any remaining Shares held by the
Purchaser as long as the Purchaser reinitiates the process specified in this
Section 9.1.

                (iv)    Nothing in this Section 9.1 shall restrict Purchaser's
ability to sell Shares at any time or from time to time or retain any proceeds
from any such sale. Purchaser agrees that Purchaser shall not be entitled to
receive from IGI any profit from the resale of Shares purchased by IGI pursuant
to Section 9.1(i).

         9.2  Covenant to Maintain Effectiveness. IGI shall keep the Shelf
Registration Statement continuously effective under the Securities Act until the
earlier of (i) the date on which the Shares may be sold pursuant to paragraph
(k) of Rule 144 (or any successor provision) promulgated by the SEC under the
Securities Act and (ii) the date as of which the Shares have been sold pursuant
to the Shelf Registration Statement.

         9.3  Covenant to Maintain Stock Exchange Listing. IGI shall take all
actions necessary to comply with the requirements of each securities exchange on
which IGI's Common Stock then trades in order to ensure that all the Shares are
listed or accepted for quotation of each such securities exchange;

         9.4  Access to Information. IGI will, as expeditiously as possible,
furnish to Purchaser, as holder of the Shares, such number of copies of the
Shelf Registration Statement, each amendment and supplement thereto, the
prospectus included in such registration statement (including each preliminary
prospectus) and such other documents as Purchaser may reasonably request in
order to facilitate the disposition of the Shares owned by Purchaser.

         9.5  Notification. IGI will, as expeditiously as possible, notify
Purchaser, at any time when a prospectus relating thereto is required to be
delivered under the Securities Act, of the happening of any event as a result of
which the prospectus included in the Shelf Registration Statement contains an
untrue statement of a material fact or omits any fact necessary to make the
statements therein, in light of the circumstances in which they were made, not
misleading, and, at the request of Purchaser, IGI will prepare a supplement or
amendment to such prospectus so that, as thereafter delivered to purchasers of
such Shares, such prospectus will not contain an untrue statement of a material
fact or omit to state any fact necessary to make the statements therein, in
light of the circumstances in which they were made, not misleading.

         9.6  Indemnification. (i) IGI agrees to indemnify, to the extent
permitted by law, each holder of the Shares, its officers and directors and each
Person who controls such holder (within the meaning of the Securities Act)
against all losses, claims, damages, liabilities and expenses caused by any
untrue or alleged untrue statement of material fact contained in any
registration statement, prospectus or preliminary prospectus or any amendment
thereof or supplement thereto or any omission or alleged omission of a material
fact required to be stated therein or necessary to make the statements therein
not misleading, except insofar as the same are caused by or contained in any
information furnished in writing to IGI by such holder expressly for use therein
or by such holder's failure to deliver a copy of the registration statement or
prospectus or any amendments or supplements thereto after IGI has furnished such
holder with a


                                      -6-
<PAGE>   8
sufficient number of copies of the same. In connection with an underwritten
offering, IGI will indemnify such underwriters, their officers and directors and
each Person who controls such underwriters (within the meaning of the Securities
Act) to the same extent as provided above with respect to the indemnification of
the holders of the Shares.

               (ii) In connection with any registration statement in which a
holder of the Shares is participating, each such holder will furnish to IGI in
writing such information and affidavits as IGI reasonably requests for use in
connection with any such registration statement or prospectus and, to the extent
permitted by law, will indemnify IGI, its directors and officers and each Person
who controls IGI (within the meaning of the Securities Act) against any losses,
claims, damages, liabilities and expenses resulting from any untrue or alleged
untrue statement of material fact contained in the registration statement,
prospectus or preliminary prospectus or any amendment thereof or supplement
thereto or any omission or alleged omission of a material fact required to be
stated therein or necessary to make the statements therein not misleading but
only to the extent that such untrue statement or omission is contained in any
information or affidavit so furnished in writing by such holder;

               (iii) Any Person entitled to indemnification hereunder will (a)
give prompt written notice to the indemnifying party of any claim with respect
to which it seeks indemnification and (b) unless in such indemnified party's
reasonable judgment a conflict of interest between such indemnified and
indemnifying parties may exist with respect to such claim, permit such
indemnifying party to assume the defense of such claim with counsel reasonably
satisfactory to the indemnified party. If such defense is assumed, the
indemnifying party will not be subject to any liability for any settlement made
by the indemnified party without its consent (but such consent will not be
unreasonably withheld). An indemnifying party who is not entitled to, or elects
not to, assume the defense of a claim will not be obligated to pay the fees and
expenses of more than one counsel for all parties indemnified by such
indemnifying party with respect to such claim, unless in the reasonable judgment
of any indemnified party a conflict of interest may exist between such
indemnified party and any other of such indemnified parties with respect to such
claim.

               (iv) The indemnification provided for under this Agreement will
remain in full force and effect regardless of any investigation made by or on
behalf of the indemnified party or any officer, director or controlling Person
of such indemnified party and will survive the transfer of securities. IGI also
agrees to make such provisions, as are reasonably requested by any indemnified
party, for contribution to such party in the event IGI's indemnification is
unavailable for any reason.

         2.5  Amendment to Annex A. Annex A of the Agreement is hereby modified
and amended in its entirety and replaced with Annex A hereto.





                                      -7-
<PAGE>   9
                                   ARTICLE 3
                FURTHER AMENDMENT; REPRESENTATION AND WARRANTIES

         3.1  Shelf Registration Statement. The Loan Parties covenant and agree
that, within one hundred eighty (180) days from the date hereof, the Loan
Parties shall file the Shelf Registration Statement with the SEC and cause such
Shelf Registration Statement to be declared effective by the SEC. If, at the end
of such 180-day period, (a) the Company shall have failed to file the Shelf
Registration Statement with the SEC, (b) the SEC shall not have declared the
Shelf Registration Statement effective, (c) the SEC shall have issued a stop
order suspending the effectiveness of the Shelf Registration Statement or (d)
the SEC shall have initiated or threatened to initiate any proceeding for that
purpose, then, in any such event, Article 9 of the Agreement, as in effect
immediately prior to the effective date of this Amendment, shall automatically
and without further action of any Person (including any Loan Party) be
reinstated in full, together with the definitions of "Put Option", "Put Option
Closing", "Put Price" and "Put Shares", and the Agreement shall be deemed
amended to such effect. The Loan Parties agree to execute and deliver such
documents, certificates, agreements and other writings and to take such other
actions as may be necessary or desirable in order to evidence or implement such
reinstatement.


         3.2  Representations and Warranties of Loan Parties. The Loan Parties
represent and warrant to the Purchaser that, after giving effect to the waivers
set forth in Article 1 of this Amendment, (a) no Default or Event of Default has
occurred and is continuing under the Agreement, the Notes or the other Purchase
Documents and (b) the representations and warranties of the Loan Parties in each
Purchase Document are true and correct with the same effect as though such
representations and warranties had been made on and as of the date hereof (other
than such representations and warranties which are made as of a specified date).


                                    ARTICLE 4
                           CONDITIONS TO EFFECTIVENESS

         4.1  ACAS Conditions to the Effectiveness of Article 1 of this
Amendment. Article 1 of this Amendment shall be effective upon satisfaction of
the conditions set forth below.

                  a.       Fleet Capital Corporation shall have evidenced, in
form and content reasonably satisfactory to ACAS, its written consent to the
transactions contemplated hereby under the terms of the Subordination Agreement
dated as of October 29, 1999;

                  b.       The Loan Parties shall have delivered to Purchaser
certified copies of the resolutions duly adopted by each of the Loan Parties'
respective board of directors authorizing the execution, delivery and
performance by such Loan Party of this


                                      -8-
<PAGE>   10
Amendment and any other agreement, instrument and document contemplated hereby
and the consummation of transactions contemplated herein; and

                  c.       The Loan Parties shall have delivered or caused to be
delivered to Purchaser (i) an executed copy of an amendment to the Senior Credit
Agreement providing, among other things, that the lenders named therein have
waived all defaults and events of default thereunder (including, without
limitation, any cross-default thereunder resulting from the occurrence of any
Default or Event of Default under the Agreement), and (ii) all such other
documents in form and substance satisfactory to Purchaser relating to the
transactions contemplated by this Amendment as Purchaser or its counsel may
reasonably request.

         Any condition specified in this Section 4.1 may be waived by the
Purchasers; provided, however, that no such waiver will be effective against the
Purchasers unless it is set forth in a writing executed by the Purchasers.

         4.2  ACAS Conditions to the Effectiveness of Article 2 of this
Amendment. Article 2 of this Amendment shall be effective as of April 12, 2000
upon satisfaction of the conditions set forth below.

                  a.       The Loan Parties shall have delivered or caused to
be delivered to Purchaser all such documents in form and substance satisfactory
to Purchaser relating to the transactions contemplated by this Amendment as
Purchaser or its counsel may reasonably request.

         Any condition specified in this Section 4.2 may be waived by the
Purchasers; provided, however, that no such waiver will be effective against the
Purchasers unless it is set forth in a writing executed by the Purchasers.


                                    ARTICLE 5

                    REFERENCE TO AND EFFECT ON THE AGREEMENT

         5.1  References. On and after the date hereof, (i) each reference in
the Agreement to "this Agreement," "hereunder," "hereof," "herein," or words of
like import shall mean and be a reference to the Agreement as amended hereby,
and (ii) each reference to the Agreement in all other Purchase Documents shall
mean and be a reference to the Agreement, as amended hereby.

         5.2  Effects. Except as specifically amended above, the Agreement, and
all other documents, instruments and agreements executed and/or delivered in
connection therewith, shall remain in full force and effect, and are hereby
ratified and confirmed.

         5.3  No Waiver. The execution, delivery and effectiveness of this
Amendment shall not operate as a waiver of any right, power or remedy of the
Purchasers, or constitute a waiver of, or consent to and departure from, any
provision of the Agreement,


                                      -9-
<PAGE>   11
or any other documents, instruments and agreements executed and/or delivered in
connection therewith.

                                    ARTICLE 6

                                  MISCELLANEOUS

         6.1 Survival. All representations, warranties, covenants and agreements
of the Loan Parties contained in the Agreement or made in writing in connection
therewith and herewith shall survive the execution and delivery of this
Amendment and the purchase of the Additional Warrants and shall continue in full
force and effect so long as any Note is outstanding and until payment in full of
all of the Loan Parties' obligations hereunder or thereunder.

         6.2 Effect; Ratification. The amendments and waivers set forth herein
are effective for the purposes set forth herein and shall be limited precisely
as written, and shall not be deemed to (i) be a consent to any amendment, waiver
or modification of any other term or condition of the Agreement or of any other
Purchase Document or (ii) prejudice any right or rights that the Purchaser or
any holder of a Note may now have or may have in the future under or in
connection with the Agreement or any other Purchase Document. This Amendment
shall be construed in connection with and as a part of the Agreement and all
terms, conditions, representations, warranties, covenants and agreements set
forth in the Agreement and each other Purchase Document, except as herein
amended or waived, are hereby ratified and confirmed and shall remain in full
force and effect.

         6.3 Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED
IN ACCORDANCE WITH, THE LAWS OF THE STATE OF MARYLAND, WITHOUT REGARD TO
CONFLICT OF LAWS PRINCIPLES.

         6.4 Severability. Whenever possible, each provision of this Amendment
shall be interpreted in such manner as to be effective and valid under
applicable law, but if any provision of this Amendment is held to be prohibited
by or invalid under applicable law in any jurisdiction, such provision shall be
ineffective only to the extent of such prohibition or invalidity, without
invalidating any other provision of this Amendment.

         6.5 Headings. Article, section and subsection headings in this
Amendment are included for convenience of reference only and shall not
constitute a part of this Amendment for any other purpose.

         6.6 Counterparts. This Amendment may be executed in any number of
counterparts and by either party hereto on separate counterparts, each of which,
when so executed and delivered, shall be an original, but all such counterparts
shall together constitute one and the same instrument.

         6.7 Integration. This Amendment, the Agreement and the other Purchase
Documents set forth the entire understanding of the parties hereto with respect
to all matters contemplated hereby and supersede all previous agreements and
understandings


                                      -10-
<PAGE>   12
among them concerning such matters. No statements or agreements, oral or
written, made prior to or at the signing hereof, shall vary, waive or modify the
written terms hereof.





                                      -11-
<PAGE>   13
                               SIGNATURE PAGES TO
                               AMENDMENT NO. 1 TO
                       NOTE AND EQUITY PURCHASE AGREEMENT


         IN WITNESS WHEREOF, the parties hereto have executed this Amendment as
of the day and year first above written.


                                    IGI, INC.


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

                                    IGEN, INC.



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

                                    IMMUNOGENETICS, INC.



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

                                    BLOOD CELLS, INC.



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




                                      -12-
<PAGE>   14
                               SIGNATURE PAGES TO
                               AMENDMENT NO. 1 TO
                       NOTE AND EQUITY PURCHASE AGREEMENT



                                    AMERICAN CAPITAL STRATEGIES,
                                    LTD., a Delaware corporation


                                    By: /s/ John Erickson
                                       ------------------------------------
                                    Name:  John Erickson
                                    Title: CFO


                                    ACS FUNDING TRUST I, a Delaware
                                    business trust


                                    By: /s/ Malon Wilkus
                                       ------------------------------------
                                    Name:  Malon Wilkus
                                    Title: Chairman





                                      -13-
<PAGE>   15
                                     ANNEX A

                        INFORMATION RELATING TO PURCHASER

                                                       Principal Amount of
Name and Address of Purchaser                          Notes to be Purchased

AMERICAN CAPITAL STRATEGIES, LTD.                      Notes $7,000,000
2 Bethesda Metro Center
14th Floor
Bethesda, MD  20814

Purchaser has assigned all
Notes to:

ACS FUNDING TRUST I
c/o American Capital Strategies, Ltd.,
  as Servicer
2 Bethesda Metro Center
14th Floor
Bethesda, MD  20814

(1)      All payments:

         If by wire:

                Account Name:  ACS Funding
                  Trust I
                Account #: 8601046967
                Bank:  LaSalle National Bank, Chicago
                ABA #: 071000505





                                      -14-
<PAGE>   16
If by mail:

                ACS Funding Trust I
                135 South LaSalle Street, Dept 4522
                Chicago, Illinois  60674-4522

         If by overnight parcel service (e.g., FedEx, UPS, etc):

                ACS Funding Trust I
                200 West Monroe Street, Suite 200
                Chicago, Illinois  60606
                Attn:  ACS Funding Trust I, Dept. 4522

         with sufficient information
         to identify the source and
         application of such funds.

(2)      All notices of payments and written confirmations of such wire
         transfers:

                American Capital Strategies, Ltd., as Servicer
                2 Bethesda Metro Center, 14th Floor
                Bethesda, Maryland  20814
                Attn:  Comptroller
                Telecopier:  (301) 654-6714

(3)      All other communications:

                American Capital Strategies, Ltd., as Servicer
                2 Bethesda Metro Center, 14th Floor
                Bethesda, Maryland  20814
                Attn:  President
                Telecopier:  (301) 654-6714






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