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                                                                    Exhibit 10.1


               AMENDMENT AND WAIVER TO LOAN AND SECURITY AGREEMENT

         This Amendment and Waiver to Loan and Security Agreement (this
"AGREEMENT") dated as of October 31, 2000 by and between Fleet Capital
Corporation (the "LENDER") and IGI, Inc., IGEN, Inc., Immunogenetics, Inc. and
Blood Cells, Inc. (each a "Borrower" and collectively, the "BORROWERS"), as
parties to that certain Loan and Security Agreement dated October 29, 1999, as
amended by that certain Amendment to Loan and Security Agreement dated as of
April 12, 2000 and that Second Amendment to Loan and Security Agreement dated as
of June 23, 2000 (as amended and in effect from time to time, the "LOAN
AGREEMENT").

                              W I T N E S S E T H:

         WHEREAS, the Borrowers have requested that the Lender waive certain
Events of Default which exist under the Loan Agreement and amend certain terms
and conditions of the Loan Agreement and the Term Loan A Note in the manner set
forth herein; and

         WHEREAS, the Lender is willing to waive such Events of Default and
amend certain terms and conditions of the Loan Agreement and the Term Loan A
Note on the terms and conditions set forth herein.

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

         SECTION 1. AMENDMENT TO THE LOAN AGREEMENT. The following is added to
the end of the first sentence of Section 1.2.1 of the Loan Agreement:

                  ; provided, that, without in any way affecting the other
         regularly scheduled quarterly principal payments, with respect to the
         quarterly principal payment due on November 1, 2000, such principal
         payment shall be in the amount of $100,000 and the balance of such
         quarterly principal payment ($133,333.33) shall be payable on December
         29, 2000.

         SECTION 2. AMENDMENT TO TERM LOAN A NOTE. The following is added to the
end of subsection (b) of the third paragraph on Page 1 of the Term Loan A Note:

                  ; provided, that, without in any way affecting the other
         regularly scheduled quarterly principal payments, with respect to the
         quarterly principal payment due on November 1, 2000, such principal
         payment shall be in the amount of $100,000 and the balance of such
         quarterly principal payment ($133,333.33) shall be payable on December
         29, 2000.

         SECTION 3. CONDITIONS PRECEDENT. The effectiveness of the amendment and
waivers contained herein shall be subject to the prior satisfaction, on or
before the date hereof, of the following conditions precedent:

                  (a) Execution and delivery by the Borrowers and the Lender of
         this Agreement.
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                  (b) The Lender shall have received a copy of the fully
         executed Amendment No. 3 to Note and Equity Purchase Agreement among
         the Borrower and American Capital Strategies, Ltd. and ACS Funding
         Trust I in form, scope and substance satisfactory to the Lender.

         SECTION 4. REPRESENTATIONS AND WARRANTIES. The Borrowers hereby
represent and warrant to the Lender that (a) all of the representations and
warranties made by the Borrowers in the Loan Agreement and the other Loan
Documents are true and correct on the date hereof as if made on and as of the
date hereof, except to the extent that any of such representations and
warranties expressly relate by their terms to a prior date (b) after giving
effect to the transactions contemplated hereby, no Event of Default under and as
defined in any of the Loan Documents has occurred and is continuing on the date
hereof.

         SECTION 5. RATIFICATION OF EXISTING AGREEMENTS. Each of the Borrowers
hereby acknowledges and agrees that nothing set forth herein shall alter or
affect the validity or effectiveness of any of the Obligations. All of the
Obligations as evidenced by or otherwise arising under the Loan Agreement and
the other Loan Documents, are, by each Borrowers' execution of this Agreement,
ratified and confirmed in all respects. In addition, by their execution of this
Agreement, each of the Borrowers represents, warrants and agrees that no
counterclaim, right of set-off, right of recoupment or defense of any kind
exists or is outstanding with respect to the Obligations. As of October 31,
2000, the aggregate principal amount of the Revolving Credit Loans outstanding
is $3,007,990.20; the principal amount of the Term Loan A outstanding is
$2,705,000.00, the principal amount of the Term Loan B outstanding is $0.00; and
the aggregate principal amount of the Capital Expenditure Loans outstanding is
$0.00.

         SECTION 6. WAIVERS. Subject to the satisfaction of the conditions set
forth below, the Lender waives those Events of Default that have occurred under
the Loan Agreement as a result of the Borrowers' failure on or before September
30, 2000 to comply with those sections of the Loan Agreement set forth on
Schedule 1 attached hereto. The waiver set forth in this Section 6 shall be
effective only for those Events of Defaults contained in the existing Loan
Agreement as specified in the preceding sentence occurring on or before
September 30, 2000 and such waiver shall not entitle the Borrowers to any future
waiver in similar or other circumstances. Without limiting the foregoing, upon
the occurrence of an Event of Default after September 30, 2000, or if an Event
of Default has occurred and is continuing on the date hereof that is not set
forth on Schedule 1, the Lender shall be free in its sole and absolute
discretion to accelerate the payment in full of the Borrowers' indebtedness to
the Lender under the Loan Agreement and the other Loan Documents, and may, if
the Lender so elects, proceed to enforce any or all of the Lender's rights under
or in respect of the Loan Agreement and the other Loan Documents and applicable
law.

         SECTION 7. NO WAIVER BY LENDER. Except as otherwise expressly provided
for herein, nothing in this Agreement shall extend to or affect in any way the
Borrowers' obligations or the Lender's rights and remedies arising under the
Loan Agreement or the other Loan Documents, and the Lender shall not be deemed
to have waived any or all of its remedies with respect to any Event of Default
(other than an Event of Default arising under the Loan Agreement as a result of
the Borrowers' failure to comply with those sections of the Loan Agreement set
forth on Schedule 1 attached hereto and then only to the extent set forth in
Section 6 hereof) or event or condition which, with notice or the lapse of time,
or both would
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become an Event of Default and which upon the Borrowers' execution and delivery
of this Agreement might otherwise exist or which might hereafter occur.

         SECTION 8. RELEASE. The Borrowers, on their own behalf and on behalf of
their shareholders, employees and agents and their successors and assigns,
hereby waive, release and discharge the Lender and all affiliates of the Lender,
and all of their directors, officers, employees, attorneys and agents, from any
and all claims, demands, actions or causes of action whether known or unknown,
arising out of or in any way relating to this Agreement, the Loan Agreement, the
Loan Documents and/or any documents, agreements, dealings or other matters
connected with the Loan Agreement, the Loan Documents or the administration
thereof.

         SECTION 9. EXPENSES. The Borrowers agree to pay to the Lender (a) on
the date hereof Lender's legal fees and disbursements incurred through the date
hereof in connection with the negotiation and preparation of this Agreement and
related matters, (b) on the date hereof Lender's examiner fees and disbursements
incurred through the date hereof, and (c) upon demand from time to time any and
all reasonable out-of-pocket costs or expenses (including commercial examiner
fees and reasonable legal fees and disbursements) hereafter incurred by the
Lender in connection with the administration of credit extended by the Lender to
the Borrowers or the preservation of or enforcement of its rights under the Loan
Agreement, the Notes and the other Loan Documents or in respect of any of the
Borrowers' other obligations to the Lender.

         SECTION 10. MISCELLANEOUS PROVISIONS.

                  (a) Except as otherwise expressly provided by this Agreement,
         all of the terms, conditions and provisions of the Loan Agreement shall
         remain the same. It is declared and agreed by each of the parties
         hereto that the Loan Agreement, as amended hereby, shall continue in
         full force and effect, and that this Agreement and the Loan Agreement
         shall be read and construed as one instrument.

                  (b) The Borrowers shall at each time as the Lender may
         reasonably request execute and deliver such further instruments, and
         take such further action, in each case further to effect the purposes
         of this Agreement, the Loan Agreement, the Notes and the other Loan
         Documents.

                  (c) This Agreement is intended to take effect under, and shall
         be construed according to and governed by, the laws of the Commonwealth
         of Pennsylvania without giving effect to principles of conflicts of
         laws.

                  (d) This Agreement may be executed in any number of
         counterparts, but all such counterparts shall together constitute but
         one instrument. In making proof of this Agreement it shall not be
         necessary to produce or account for more than one counterpart signed by
         each party hereto by and against which enforcement hereof is sought.
         TIME IS OF THE ESSENCE AS TO ALL OF THE PROVISIONS HEREIN.

                  (e) THE BORROWERS AND THE LENDER HEREBY WAIVE THEIR RIGHT TO A
         JURY TRIAL WITH RESPECT TO ANY ACTION OR CLAIM ARISING OUT OF ANY
         DISPUTE IN CONNECTION WITH THIS AGREEMENT, THE LOAN AGREEMENT,
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         THE NOTES, THE OTHER LOAN DOCUMENTS OR ANY OF THE BORROWERS'
         OBLIGATIONS HEREUNDER OR THEREUNDER OR THE PERFORMANCE OF SUCH
         OBLIGATIONS.

         IN WITNESS WHEREOF, each of the parties hereto have caused this
Agreement to be executed in its name and behalf by its duly authorized officer
as of the date first written above.


                               IGI, INC.



                               By:
                                  ----------------------------------------------

                                    Its:
                                        ----------------------------------------


                               IGEN, INC.



                               By:
                                  ----------------------------------------------

                                    Its:
                                        ----------------------------------------


                               IMMUNOGENETICS, INC.



                               By:
                                  ----------------------------------------------

                                    Its:
                                        ----------------------------------------


                               BLOOD CELLS, INC.



                               By:
                                  ----------------------------------------------

                                    Its:
                                        ----------------------------------------


                               FLEET CAPITAL CORPORATION



                               By: /s/ Stephen M. Spencer
                                  ----------------------------------------------
                                       Stephen M. Spencer

                                    Its: Senior Vice President
                                        ----------------------------------------
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                                   SCHEDULE 1

1.       The failure of the Borrowers to comply with Section 8.2.3(ii) for the
         period beginning on June 23, 2000 through September 30, 2000.

2.       The failure of the Borrowers to comply with Section 8.3.1 for the
         period beginning on June 23, 2000 through September 30, 2000.

3.       The failure of the Borrowers to comply with Section 8.3.2 for the
         period beginning on June 23, 2000 through September 30, 2000.