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                                                                    Exhibit 10.1


                           SECOND AMENDMENT TO LEASE

         This instrument is a Second Amendment to Lease dated 3rd day of March,
2005, between ROTARY INTERNATIONAL, an Illinois not-for-profit corporation (the
"Landlord") and NORTHFIELD LABORATORIES, INC., an Illinois corporation (the
"Tenant").

                                    RECITALS

         First Illinois Bank of Evanston, N.A., not individually but solely as
Trustee under Trust Agreement dated March 17, 1975 and known as Trust No.
R-1809, Rotary International, an Illinois not-for-profit corporation, and
Northfield Laboratories, Inc. entered into a Sublease dated April 20, 1988 (the
"Sublease") for certain premises on the tenth floor of One Rotary Center,
Evanston, Illinois (the "Premises").

         Bank One Illinois, N.A. succeeded to all of the interest of Landlord.

         The underlying Lease dated April 14, 1975 between First National Bank
and Trust of Evanston, the predecessor to First Illinois Bank of Evanston, N.A.,
as Trustee under Trust No. R-1809 and American Hospital Supply Corporation, with
respect to which this Sublease was made, expired December 31, 2001.

         Bank One Illinois, N.A., Rotary International and Northfield
Laboratories, Inc. amended the Sublease in certain respects and agreed that
commencing January 1, 2002, the Sublease, as amended, constituted a direct lease
from Bank One Illinois, N.A. to Northfield Laboratories, Inc. Accordingly, the
Sublease is herein referred to as the Lease.

         Rotary International, the Owner of the beneficial interest of Trust No.
R-1089 has acquired title to One Rotary Center from Bank One Illinois, N.A., as
Trustee.

         NOW, THEREFORE, in consideration for the mutual covenants for their
respective benefits contained herein, Landlord and Tenant agree that the Lease
is hereby amended, effective February 15, 2006 (except certain provisions shall
be applicable on the dates herein stated), as follows:

         1. EXTENSION OF TERM. The Term of the Lease is hereby extended by a
period beginning February 15, 2006 and ending February 14, 2011 (the "Further
Extended Term").

         2. BASE RENT. The Base Rent for the Further Extended Term shall be as
set forth on Exhibit "A" attached hereto.

         3. EXPANSION SPACE. Effective August 1, 2005, the 2,518 rentable square
feet on the tenth floor that is described on Exhibit "B" attached hereto (the
"Expansion Space") shall become a part of the Premises. Landlord shall give
Tenant possession of the Expansion Space on June 1, 2005 to enable Tenant, at
its own expense, to complete the Tenant's improvements to the Expansion Space.
Tenant is taking the Expansion Space in "AS IS' condition. The Base Rent for the
Expansion Space for the period August 1, 2005 through February 14, 2006 shall be
as set forth on Exhibit "C" hereto. Thereafter, the Base Rent for the Expansion
Space is included in the Base Rent set forth on Exhibit "A" hereto.


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         4. PROPORTIONAL SHARE. Effective August 1, 2005, Tenant's Proportional
Share shall be increased to 3.67%, which is the percentage determined by
dividing the number of rentable square feet in the Premises (13,518) by the
number of rentable square feet in the Building (368,757).

         5. ADDITIONAL PARKING. Effective August 1, 2005, Tenant shall be
entitled to three (3) additional parking spaces. These spaces will be at the
Best Western Hotel that is approximately one block south of the Building.
Tenant's use of these spaces will be limited to 8:00 A.M. to 6:00 P.M. Monday
through Friday. Tenant shall be required to pay the market rate determined from
time to time for these parking spaces. The current market rate per space is
$75.00 per month. While Landlord will use commercially reasonable efforts to
maintain Tenant's right to use these spaces, the spaces are owned and controlled
by a third party. In the event the third party terminates Landlord's right to
use these spaces, Landlord shall have the right to terminate Tenant's right to
use these spaces.

         6. TENANT'S OPTION TO TERMINATE. Article 32 of the Lease, as amended by
the Amendment to Lease, is deleted effective immediately and replaced with the
following:

                  "Tenant shall have the option to terminate this Lease,
         effective any time after February 14, 2009 ("Option to Terminate").
         Tenant may exercise its Option to Terminate only by serving notice, by
         fax, e-mail or otherwise in accordance with the notice provisions of
         the Lease, upon Landlord not less than six (6) months prior to the
         effective date of the termination ("Early Termination Date"). If notice
         is by fax or e-mail and Landlord challenges the notice on the basis
         that it has not received the notice, the notice shall not be effective
         unless Tenant provides Landlord a written confirmation establishing
         that the notice was faxed to Landlord's correct fax number or e-mailed
         to Landlord's correct e-mail address. Tenant shall pay Landlord, in
         addition to all other amounts due Landlord through the Early
         Termination Date pursuant to this Lease, a cancellation payment
         ("Cancellation Payment"). The Cancellation Payment shall be comprised
         of (a) the lesser of (i) an amount equal to the Base Rent and
         Additional Rent payments that otherwise would be due for the period
         commencing on the Early Termination Date and ending on the expiration
         date of the Term of the Lease, or (ii) an amount equal to the Base Rent
         and Additional Rent payments that otherwise would be due for the three
         (3) months immediately following the Early Termination Date and (b), to
         compensate Landlord for the real estate brokerage commissions incurred
         and paid by Landlord with respect to this Second Amendment to Lease, an
         amount equal to the product of $831.90 multiplied times the number of
         months commencing with the Early Termination Date and ending with
         expiration date of the Term of the Lease.

                  Tenant shall pay Landlord the applicable Cancellation Payment
         at the time it serves the written notice that it is exercising this
         option to terminate. Upon the Early Termination Date, Tenant shall
         return the Premises to Landlord in accordance with the requirements of
         the Lease, and the Term of this Lease shall be deemed to have expired
         by lapse of time.

                  It is expressly agreed that (1) time is of the essence of the
         foregoing option and payment, and the timely serving of notice of
         election to terminate and the timely payment of the Cancellation
         Payment to Landlord shall be a condition precedent to the effectiveness
         of Tenant's early termination of this Lease; and (2), at Landlord's

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         election, Tenant's failure to pay the applicable Cancellation Payment
         within ten (10) days of written notice from Landlord shall operate to
         abrogate Tenant's early termination of this Lease and shall reinstate
         this Lease and all the terms and conditions therein as of the Early
         Termination Date."

         7. BASE YEAR. Effective February 15, 2006, the Base Year shall be 2005.
Taxes for the Base Year shall be the 2004 Taxes paid in 2005. Operating Expenses
for the Base Year shall be the Operating Expenses paid in 2005. All references
to Taxes shall mean Taxes paid, not Taxes accrued during a particular year.

         8. TENANT'S OPTION TO EXTEND. Provided this Lease is then in full force
and effect and that Tenant is not then in Default under this Lease, Tenant shall
have the option to extend the Term of this Lease ("Option to Extend") for an
additional five (5) year period ("Extension Period"). Tenant may exercise said
option only by serving written notice upon Landlord not less than nine (9)
months prior to the expiration of the Further Extended Term.

         All terms and conditions of this Lease shall apply to the leasing of
the Premises during the Extension Period, except that the amount of Rent for the
Premises at the commencement of the Extension Period shall be revised to be the
Market Rent (as hereinafter defined). Within thirty (30) days following receipt
of Tenant's notice, Landlord shall provide Tenant with its assessment of what
the Market Rent is for the Premises for such renewal period. In determining the
Market Rent Landlord shall take into consideration customary rent and lease
concessions provided to other creditworthy tenants leasing similar sized
premises in the Evanston Office Market at the time of Tenant's exercise of this
option. Within fifteen (15) days after receipt of Landlord's determination of
Market Rent, Tenant shall either accept or reject the Market Rent in writing. If
Tenant rejects Landlord's determination of the Market Rent, then Landlord and
Tenant shall attempt to mutually agree upon Market Rent within thirty (30) days
of the date of receipt by Landlord of Tenant's rejection of Landlord's
determination of the Market Rate. If Landlord and Tenant are unable to agree
upon Market Rent during such thirty (30) day period, this Option to Extend shall
immediately terminate.

         "Market Rent" shall mean the effective rent (i.e., taking into account
any tenant concessions which are then being provided in the marketplace, such as
but not limited to rent abatement, cash allowance or credits for tenant
improvements and relocation costs) that would be received by tenants renting
comparable space in comparable buildings in Evanston and Skokie, Illinois or
renewing leases in the Building for a comparable term commencing on or about the
dates of the commencement of the applicable Extension Period.

         9. DEMISING WALL. Landlord agrees to pay for the cost of the demising
wall between the Expansion Space and the balance of the floor not leased by
Northfield Laboratories, Inc. Landlord shall commence work on the demising wall
on June 1, 2005 and shall complete the demising wall by July 1, 2005. If the
demising wall is not completed by July 1, 2005, rent on the Expansion Space
shall abate for one day for each day after July 1, 2005 that the demising wall
is not completed.

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         10. ADDRESS FOR PAYMENT. Effective immediately, Section C of Article 2
of the Lease is further amended to provide that all payments are to be made to
Cushman & Wakefield of Illinois, Inc., as agent for Rotary International, Inc.,
at P. O. Box 88256, Chicago, Illinois 60680-1256.

         11. NOTICE. Effective immediately, Article 27 of the Lease is further
amended to provide that the correct address for the copy of any notice sent to
Landlord is as follows:

                            Charles R. Staley
                            29 South LaSalle Street
                            Suite 950
                            Chicago, Illinois 60603

         12. "AS IS" CONDITION. Tenant is taking both the Premises and the
Expansion Space in "AS IS" condition.

         13. RIGHT TO SHIFT LOCATION OF PREMISES. Article 36 of the Lease is
hereby deleted.

         14. CONFLICT. In the event of any conflict between the terms and
provisions of this Second Amendment To Lease and the terms and provisions of the
of the Lease as previously amended, this Second Amendment To Lease shall be
controlling.

         15. CAPITALIZED TERMS. All capitalized terms which are not defined
herein shall have the meaning given them in the Lease.

         IN WITNESS WHEREOF, this Second Amendment to Lease was executed on
behalf of Landlord and Tenant the date first above written.

LANDLORD:
                                ROTARY INTERNATIONAL, AN ILLINOIS NOT-FOR-PROFIT
                                CORPORATION

                                By:    /s/ Ed Futa
                                   ---------------------------------------------
                                           Ed Futa
                                Its: General Secretary
                                   ---------------------------------------------

TENANT:                         NORTHFIELD LABORATORIES, INC., AN ILLINOIS
                                CORPORATION

                                By:  /s/ Jack Kogut
                                   ---------------------------------------------
                                         Jack Kogut
                                Its: Sr. VP Finance
                                    --------------------------------------------


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