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EXHIBIT *(10.44)

                            PATENT SECURITY AGREEMENT
                             (United States Patents)

This Patent Security Agreement ("Agreement") is made this 29th day of October,
1999, by IGI, INC., a Delaware corporation having a mailing address at Wheat
Road and Lincoln Avenue, Buena, NJ 08310 ("Grantor") and delivered to AMERICAN
CAPITAL STRATEGIES, LTD., a Delaware corporation having a mailing address at 2
Bethesda Metro Center, 14th Floor, Bethesda, Maryland 20814 ("Lender").

                                   BACKGROUND

A. Grantor has entered into that certain Note and Equity Purchase Agreement
dated as of even date herewith among Grantor, IGEN, Inc., ImmunoGenetics, Inc.,
and Blood Cells, Inc. (collectively, "Borrowers") and Lender (as it may
hereafter be supplemented, restated, amended, superseded or replaced from time
to time, the "Purchase Agreement"). Capitalized terms not defined herein shall
have the meanings given to such terms in the Purchase Agreement.

B. This Agreement is being executed contemporaneously with that certain Security
Agreement of even date herewith among Borrowers and Lender (as it may hereafter
be supplemented, restated, amended, superseded or replaced from time to time,
the "Security Agreement"), under which, inter alia, Grantor is granting Lender a
lien on and security interest in certain assets of Grantor associated with or
relating to products leased or sold or services provided under Grantor's patents
and the goodwill associated therewith as security for the payment and
performance of all the Obligations (as defined in the Security Agreement) of all
the Borrowers, and under which Lender is entitled to foreclose or otherwise deal
with such assets and patents under the terms and conditions set forth therein.

C. Pursuant to the Security Agreement, Lender is acquiring a lien on, and
security interest in, and license to use (which license is conditioned upon the
occurrence and continuance of an Event of Default), among other things, (i) the
United States Letters Patent and the inventions described and claimed therein
set forth on Schedule A hereto and (ii) the applications for Letters Patent and
the inventions described and claimed therein set forth on Schedule A hereto and
any United States Letters Patent which may be issued upon any of said
applications, together with all the goodwill of Grantor associated therewith and
represented thereby, as security for all of the Obligations, and desires to have
its security interest in such letters patent and applications confirmed by a
document identifying same and in such form that it may be recorded in the United
States Patent and Trademark Office.

NOW THEREFORE, with the foregoing Background hereinafter deemed incorporated by
reference and made a part hereof, and in consideration of the premises and
mutual promises herein contained, the parties hereto, intending to be legally
bound hereby, covenant and agree as follows:
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1.   In consideration of and pursuant to the terms of the Purchase Agreement,
     and for other good, valuable and sufficient consideration, the receipt of
     which is hereby acknowledged, and to secure the payment and performance of
     all the Obligations of all Borrowers under the Purchase Documents, Grantor
     grants to Lender a lien on and security interest in all patents and patent
     applications, including, without limitation, the inventions and
     improvements described and claimed therein, and those patents and patent
     applications listed on Schedule "A" attached hereto and made a part hereof,
     and the reissues, divisions, continuations, renewals, extensions and
     continuations-in-part thereof (collectively, the "Schedule A Patents"), all
     of Grantor's rights and obligations pursuant to any license agreements
     between Grantor and any other Person or Persons, whether Grantor is a
     licensor or licensee under any such license agreements, including, without
     limitation, the licenses listed on Schedule "C" attached hereto and made a
     part hereof with respect to the patents and patent applications listed on
     Schedule "B" attached hereto and made a part hereof (collectively the
     "Schedule B Patents" and, together with the Schedule A Patents, the
     "Patents"), and, subject to the terms of such licenses, the right to
     prepare for sale, sell and advertise for sale, all Inventory now or
     hereafter owned by such Assignor and now or hereafter covered by such
     licenses (collectively, the "Licenses", and together with the Patents, the
     "Patent Rights") and all proceeds thereof and all Grantor's right, title,
     interest, claims and demands that Grantor has or may have in profits and
     damages for past and future infringements of the Patent Rights (such
     rights, interest, claims and demand being herein called the "Claims") (the
     Patent Rights and Claims are collectively referred to as the "Patent
     Collateral").

2.   Grantor hereby covenants and agrees to maintain the Patent Collateral in
     full force and effect until all of the Obligations are satisfied in full.

3.   Grantor represents, warrants and covenants to Lender that:

     (a) The Patent Collateral is subsisting and has not been adjudged invalid
or unenforceable;

     (b) All of the Patent Rights subsisting, and, to the best of Grantor's
knowledge, valid and enforceable;

     (c) Grantor is the sole and exclusive owner of the entire and unencumbered
right, title and interest in and to the Patent Collateral (excepting the
Schedule B Patents, but including the Grantor's rights under the Licenses).
Except for Liens permitted under Section 7.2(b) of the Purchase Agreement, all
of the Patent Collateral (other than the Schedule B Patents, but including
Grantor's right under the Licenses) is free and clear of any liens, charges and
encumbrances including, without limitation, pledges, assignments, options and
covenants by Grantor not to sue third persons;

     (d) Except for Liens permitted under Section 7.2(b) of the Purchase
Agreement, the Grantor's rights under the Licenses are free and clear of any
liens, claims,



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charges and encumbrances, including, without limitation, pledges, assignments,
options, and covenants by Grantor not to sue third persons;

     (e) Grantor has no notice of any suits or actions commenced or threatened
against it, or notice of claims asserted or threatened against it, with
reference to the Patent Collateral;

     (f) Grantor has the unqualified right, power and authority to enter into
this Agreement and perform its terms; and

     (g) Grantor has complied with, and will continue for the duration of this
Agreement to comply with the requirements set forth in 15 U.S.C.
Section1051-1127 and any other applicable statutes, rules and regulations in
connection with its use of the Patent Collateral except where failure to comply
would not have a material adverse effect on Grantor or its Property.

4.   Grantor further covenants that:

     (a) Until all of the Obligations have been satisfied in full, Grantor will
not enter into any agreement which is inconsistent with Grantor's obligations
under this Agreement, Grantor's obligations under the Purchase Agreement or
which may restrict or impair Lender's rights or priorities hereunder.

     (b) If Grantor acquires rights to any new owned Patent Collateral, the
provisions of this Agreement shall automatically apply thereto and such Patent
Collateral shall be deemed part of the Patent Collateral. Grantor shall give
Lender prompt written notice thereof along with an amended Schedule "A."
Furthermore, if Grantor acquires rights as a licensee to any new patents, the
provisions of this Agreement shall automatically apply thereto and such patent
shall be deemed part of the Schedule B Patents, and any license agreement
pursuant to which Grantor acquires such rights shall be deemed to be included in
the definition of "Licenses." Grantor shall give Lender written notice promptly
upon its first use thereof along with an amended Schedule "B."

5.   So long as this Agreement is in effect and so long as Grantor has not
     received notice from Lender that an Event of Default has occurred and is
     continuing under the Notes and the Purchase Agreement and that Lender has
     elected to exercise its rights hereunder (i) Grantor shall continue to have
     the exclusive right to use the Patent Collateral; and (ii) Lender shall
     have no right to use the Patent Collateral or issue any exclusive or
     non-exclusive license with respect thereto, or assign, pledge or otherwise
     transfer title in the Patent Collateral to anyone else.

6.   Grantor agrees not to sell, license, grant any option, assign or further
     encumber its rights and interest in the Patent Collateral to any entity or
     person other than Grantor without the prior written consent of Lender or as
     may be expressly permitted under the Purchase Agreement. Notwithstanding
     the foregoing, and providing that no Default or Event of Default has
     occurred and is outstanding, Grantor shall be entitled to license any
     Patents in exchange for fair market consideration in the exercise of its
     reasonable business judgment.



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7.   Anything herein contained to the contrary notwithstanding, if and while
     Grantor shall be in default hereunder or an Event of Default exists under
     the Notes or the Purchase Agreement, Grantor hereby covenants and agrees
     that Lender as the holder of a security interest under the Uniform
     Commercial Code, as now or hereafter in effect in the State whose law
     governs the interpretation of the Purchase Documents, may take such action
     permitted under the Purchase Documents, hereunder or under any law, in its
     exclusive discretion, to foreclose upon the Patent Collateral covered
     hereby. For such purposes, Grantor hereby authorizes and empowers Lender,
     its successors and assigns to make, constitute and appoint any officer or
     agent of Lender as Lender may select, in its exclusive discretion, as
     Grantor's true and lawful attorney-in-fact, with the power to endorse
     Grantor's name on all applications, documents, papers and instruments
     necessary for Lender to use the Patent Collateral or to grant or issue any
     exclusive or non-exclusive license under the Patent Collateral to anyone
     else, or necessary for Lender to assign, pledge, convey or otherwise
     transfer title in or dispose of the Patent Collateral to anyone else
     including, without limitation, the power to execute a Patent Collateral
     assignment in the form attached hereto as Exhibit 1. Grantor hereby
     ratifies all that such attorney shall lawfully do or cause to be done by
     virtue hereof, except for the gross negligence or willful misconduct of
     such attorney. This power of attorney shall be irrevocable for the life of
     this Agreement, the Purchase Documents, and until all of the Obligations of
     all of the Borrowers are indefeasibly paid and satisfied in full.

8.   This Agreement shall be subject to the terms, provisions, and conditions
     set forth in the Purchase Agreement and may not be modified without the
     written consent of the party against whom enforcement is being sought.

9.   All rights and remedies herein granted to Lender shall be in addition to
     any rights and remedies granted to Lender under the Purchase Documents. In
     the event of an inconsistency between this Agreement and Purchase
     Agreement, the language of this Agreement shall control.

10.  Upon Borrowers' performance of all of the Obligations under the Purchase
     Documents and full and unconditional satisfaction of all of the Borrowers'
     Obligations, Lender shall execute and deliver to Grantor all documents
     reasonably necessary to terminate Lender's security interest in the Patent
     Collateral.

11.  Any and all reasonable fees, costs and expenses, of whatever kind or
     nature, including the reasonable attorneys' fees and legal expenses
     incurred by Lender in connection with the preparation of this Agreement and
     all other documents relating hereto and the consummation of this
     transaction, the filing or recording of any documents (including all taxes
     in connection therewith) in public offices, the payment or discharge of any
     taxes, reasonable counsel fees, maintenance fees, encumbrances or costs
     otherwise incurred in protecting, maintaining, preserving the Patent
     Collateral, or in defending or prosecuting any actions or proceedings
     arising out of or related to the Patent Collateral, in each case in
     accordance with the terms of this Agreement, shall be borne and paid by
     Grantor on demand by


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<PAGE>   5
     Lender and until so paid shall be added to the principal amount of the
     Obligations to Lender and shall bear interest at the rate of interest
     determined in accordance with Section 8.2(c) of the Purchase Agreement.

12.  Subject to the terms of the Purchase Agreement and the Notes, Grantor shall
     have the duty to prosecute diligently any application with respect to the
     Patent Collateral (other than the Schedule B Patents or any applications or
     inventions relating thereto) pending as of the date of this Agreement or
     thereafter, until Borrowers' Obligations shall have been satisfied in full,
     to preserve and maintain all rights in the Patent Collateral (other than
     the Schedule B Patents or any application or inventions relating thereto),
     and upon reasonable request of Lender, Grantor shall make federal
     application on registrable but unregistered Patent Collateral (other than
     the Schedule B Patents or any applications, or inventions relating thereto)
     belonging to Grantor and licensed to Grantor. To the extent that Grantor
     has the duty or right to make any patent applications under any License,
     Grantor shall have the same duties with respect to the Schedule B Patents
     as stated in the previous sentence. Grantor shall not abandon any Patent
     Collateral without the prior written consent of the Lender, which consent
     shall not be unreasonably withheld.

13.  Grantor shall have the right to bring suit in its own name to enforce the
     Patent Collateral, in which event Lender may, if Grantor reasonably deems
     it necessary, be joined as a nominal party to such suit if Lender shall
     have been satisfied, in its sole discretion, that it is not thereby
     incurring any risk of liability because of such joinder. Grantor shall
     promptly, upon demand, reimburse and indemnify Lender for all damages,
     costs and expenses, including attorneys' fees and costs, incurred by Lender
     in the fulfillment of the provisions of this paragraph.

14.  Upon the occurrence of an Event of Default under the Purchase Agreement or
     hereunder, Lender may, without any obligation to do so, complete any
     obligation of Grantor hereunder, in Grantor's name or in Lender's name, but
     at the expense of Grantor, and Grantor hereby agrees to reimburse Lender in
     full for all expenses, including, without limitation, all attorneys' fees
     incurred by Lender in protecting, defending and maintaining the Patent
     Collateral.

15.  No course of dealing between Grantor and Lender, nor any failure to
     exercise, nor any delay in exercising, on the part of Agent, any right,
     power or privilege hereunder, shall operate as a waiver thereof, and all of
     Lender's rights and remedies with respect to the Patent Collateral, whether
     established hereby or by the Purchase Documents, or by any other future
     agreements between Grantor and Lender or by law, shall be cumulative and
     may be exercised singularly or concurrently.

16.  The provisions of this Agreement are severable and the invalidity or
     unenforceability of any provision herein shall not affect the remaining
     provisions which shall continue unimpaired and in full force and effect.



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<PAGE>   6
17.  This Agreement shall inure to the benefit of and be binding upon the
     respective successors and permitted assigns of the parties.

18.  This Agreement shall be governed by and construed in conformity with the
     laws of the State of Maryland, without regard to its otherwise applicable
     principles of conflicts of laws.

19.  GRANTOR AND LENDER EACH WAIVES ANY AND ALL RIGHTS EITHER MAY HAVE TO A JURY
     TRIAL ARISING IN CONNECTION WITH ANY PROCEEDING OR CONTROVERSY RELATING TO
     THIS AGREEMENT OR ANY OTHER AGREEMENT BETWEEN GRANTOR AND LENDER.


                  [REMAINDER OF PAGE LEFT INTENTIONALLY BLANK]



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<PAGE>   7
20. GRANTOR AND LENDER EACH WAIVES ANY AND ALL RIGHTS EITHER MAY HAVE TO A JURY
TRIAL ARISING IN CONNECTION WITH ANY PROCEEDING OR CONTROVERSY RELATING TO THIS
AGREEMENT OR ANY OTHER AGREEMENT BETWEEN GRANTOR AND LENDER.

21. THE OBLIGATIONS SECURED HEREBY AND THE SECURITY INTERESTS GRANTED HEREUNDER
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, AS AGENT FOR THE SENIOR LENDERS, AMERICAN
CAPITAL STRATEGIES, LTD., AND ASSIGNORS TO THE INDEBTEDNESS AND OTHER
LIABILITIES OWED BY ASSIGNORS 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 ASSIGNEE HEREUNDER, BY ITS ACCEPTANCE HEREOF,
ACKNOWLEDGES AND AGREES TO BE BOUND BY THE PROVISIONS OF THE SUBORDINATION
AGREEMENT.


IN WITNESS WHEREOF, the parties hereto have executed this Patent Security
Agreement, under seal, the day and year first above written.

                                    IGI, INC.



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





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<PAGE>   8
                            CORPORATE ACKNOWLEDGMENT

UNITED STATES OF AMERICA            :
STATE OF                            :   SS
COUNTY OF                           :




      On this 29th of October, 1999, before me personally appeared to me known
and being duly sworn, deposes and says that s/he is
 of IGI, INC.; that s/he signed the Agreement thereto as such officer pursuant
to the authority vested in him by law; that the within Agreement is the
voluntary act of such corporation; and s/he desires the same to be recorded as
such.







                                    Notary Public

                                    My Commission Expires:





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<PAGE>   9
                                   SCHEDULE A

<TABLE>
<CAPTION>
Patent                        Registration No.        Country     Filing Date
<S>                           <C>                     <C>         <C>


</TABLE>




























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<PAGE>   10
                                    EXHIBIT I

                                PATENT ASSIGNMENT

WHEREAS, IGI, INC., a Delaware corporation ("Grantor") is the registered owner
of: (i) the United States Letters Patent and the inventions described and
claimed therein set forth on Schedule A hereto (hereinafter referred to
collectively as the "Patents"); (ii) the applications for Letters Parent and the
inventions described and claimed therein set forth on Schedule A hereto and any
United States Letters Patent which may be issued upon any of said applications
(hereinafter referred to collectively as the "Applications"), which are
registered with the United States Patent and Trademark Office.

WHEREAS, in conjunction with the Patents and Applications, Grantor may use or
adopt any reissues, extensions, divisions or continuations of the Patents or
Applications (such reissues, extension, divisions and continuations being herein
referred to collectively as the "Reissued Patents"); may be entitled to all
future royalties or other fees paid or payments made to Grantor in respect of
the Patents (hereinafter referred to collectively as the "Royalties"), (the
Patents, Applications and the Reissued Patents and the Royalties being herein
referred to collectively as the "Patent Rights") and may be entitled to profits
and damages for past and future infringements of the Patent Rights (such rights,
interest, claims and demand being herein called the "Claims') (the Patent Rights
and Claims are collectively referred to as the "Patent Collateral").

WHEREAS,                         , ("Grantee") having a place of business at
                        is desirous of acquiring said Patent Collateral;

NOW THEREFORE, for good and valuable consideration, receipt of which is hereby
acknowledged, and intending to be legally bound hereby, Grantor, its successors
and assigns, does hereby transfer, assign and set over unto Grantee, its
successors, transferees and assigns, all of its present and future right, title
and interest in and to the Patent Collateral and all proceeds thereof and all
goodwill associated therewith. No rights or duties of any kind are intended to
be granted or conferred upon Grantee unless and until this Patent Assignment is
recorded with the United States Patent and Trademark Office.

IN WITNESS WHEREOF, the undersigned has caused this Patent Assignment to be
executed as of the 29th day of October, 1999.


                                    IGI, INC.



                                    By:
                                              As Attorney-in-fact




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<PAGE>   11
STATE OF                :
                        : S.S.
COUNTY OF               :

On this 29th day of October, 1999, before me, a Notary Public for the said
County and State, personally appeared known to me or satisfactorily proven to me
to be attorney-in-fact on behalf of IGI, INC. ("Grantor") and s/he acknowledged
to me that s/he executed the foregoing Patent Assignment on behalf of Grantor,
and as the act and deed of Grantor for the purposes therein contained.

IN WITNESS WHEREOF, I hereunto set my hand and official seal.





                                         Notary Public





My Commission Expires:






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<PAGE>   12
                                POWER OF ATTORNEY

IGI., INC., a Delaware corporation, ("Grantor"), hereby authorizes AMERICAN
CAPITAL STRATEGIES, LTD., its successors and assigns, and any officer or agent
thereof (collectively, "Lender") as Grantor's true and lawful attorney-in-fact,
with the power to endorse Grantor's name on all applications, assignments,
documents, papers and instruments necessary for Lender to enforce and effectuate
its rights under a certain Patent Security Agreement (United States Patents)
between Grantor and Lender dated the date hereof (as it may hereafter be
supplemented, restated, superseded, amended or replaced, the "Patent
Agreement"), including, without limitation, the power to use the Patent
Collateral (as defined in the Patent Agreement), to grant or issue any exclusive
or nonexclusive license under the Patent Collateral to anyone else, or to
assign, pledge, convey or otherwise transfer title in or dispose of the Patent
Collateral.

This Power of Attorney is given and any action taken pursuant hereto is intended
to be so given or taken pursuant to a certain Loan and Security agreement
bearing even date herewith between Grantor and Lender as it may be hereinafter
supplemented, restated, superseded, amended or replaced.

Grantor hereby unconditionally ratifies all that such attorney shall law fully
do or cause to be done by virtue hereof.

This Power of Attorney shall be irrevocable for the life of the Patent
Agreement.

IN WITNESS WHEREOF, the Grantor has executed this Power of Attorney, under seal,
this 29th day of October, 1999.

                                    IGI, INC.



                                    By:    /s/ MANFRED HANUSCHEK
                                    Name:  MANFRED HANUSCHEK
                                    Title: CFO

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<PAGE>   13
                            CORPORATE ACKNOWLEDGMENT

UNITED STATES OF AMERICA            :
STATE OF                            :           SS
COUNTY OF                           :


On this 29th of October, 1999 personally appeared, to me known and being duly
sworn, deposes and says that s/he is ____________ of IGI, INC., the Grantor
corporation described in the foregoing Power of Attorney; that s/he signed the
Power of Attorney as such officer pursuant to the authority vested in her/him by
law; that the within Power of Attorney is the voluntary act of such corporation;
and s/he desires the same to be recorded as such.






                                    Notary Public

                                    My Commission Expires




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