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                                                                     EXHIBIT 4.1

             Warrant to Purchase up to 58,632 Shares of Common Stock

                                       of

                          Northfield Laboratories Inc.

                            PLACEMENT AGENT'S WARRANT

                               Dated: May 18, 2004

      This certifies that SG COWEN & CO., LLC (herein sometimes called the
"PLACEMENT AGENT") or its permitted transferee (the Placement Agent or any such
transferee is sometimes herein called the "HOLDER") is entitled to purchase from
NORTHFIELD LABORATORIES INC., a Delaware corporation (the "COMPANY"), at the
price and during the period as hereinafter specified, up to 58,632 shares (the
"SHARES") (equal to three percent (3%) of the number of shares of common stock,
$0.01 par value per share of the Company (the "COMMON STOCK"), sold pursuant to
the purchase agreements in the form included as Exhibit A to the Placement Agent
Agreement (as defined below)) at a purchase price of $13.73 per share (equal to
the average Closing Price of a Share, as reported on the Nasdaq National Market
for the three consecutive Trading Days (as defined herein) ending on and
including the date of the Placement Agent Agreement (as defined herein)),
subject to adjustment as described below (as so adjusted from time to time, the
"EXERCISE PRICE")), at any time during the four (4) year period commencing one
(1) year from the Closing Date.

      This Placement Agent's Warrant (the "PLACEMENT AGENT'S WARRANT") is issued
pursuant to a Placement Agent Agreement between the Company and SG Cowen & Co.,
LLC, as Placement Agent, in connection with a public offering, through the
commercially reasonable efforts of the Placement Agent, of up to 1,954,416
shares of Common Stock as therein described (the "PLACEMENT AGENT AGREEMENT").
All capitalized terms used herein and not otherwise defined, shall have the
meanings ascribed to such terms in the Placement Agent Agreement.

      1. EXERCISE. The rights represented by the Placement Agent's Warrant shall
be exercisable at the Exercise Price, and during the periods as follows:

            (a) During the period from the Closing Date to and through May 17,
2005 (the "FIRST ANNIVERSARY DATE"), inclusive, the Holder shall have no right
to purchase any Shares hereunder.

            (b) At any time and from time to time between, May 18, 2005 and May
17, 2009, (the expiration of five (5) years from the Closing Date, i.e. the
"EXPIRATION DATE") inclusive, the Holder shall have the right to purchase such
number of Shares hereunder as is determined pursuant to Section 1(c) hereof at
the Exercise Price.

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            (c) This Placement Agent's Warrant shall be exercisable for such
number of shares (rounded to the nearest whole number) as is equal to the
aggregate number of shares of Stock purchased by the Purchasers at the Closing
multiplied by 0.03.

            (d) After the Expiration Date, the Holder shall have no right to
purchase all or any portion of the Shares hereunder.

      2. PAYMENT FOR SHARES; ISSUANCE OF CERTIFICATES; NET EXERCISE.

            (a) The rights represented by the Placement Agent's Warrant may be
exercised at any time within the periods above specified, in whole or in part,
by (i) the surrender of the Placement Agent's Warrant (with the purchase form at
the end hereof properly executed) at the principal executive office of the
Company (or such other office or agency of the Company as it may designate by
notice in writing to the Holder at the address of the Holder appearing on the
books of the Company); (ii) payment to the Company of the Exercise Price then in
effect for the number of Shares specified in the above-mentioned purchase form
together with applicable stock transfer taxes, if any; and (iii) delivery to the
Company of a duly executed agreement signed by the person(s) designated in the
purchase form to the effect that such person(s) agree(s) to be bound by the
provisions of Section 6 and subsections (b), (c) and (d) of Section 7 hereof.
The Placement Agent's Warrant shall be deemed to have been exercised, in whole
or in part to the extent specified, immediately prior to the close of business
on the date the Placement Agent's Warrant is surrendered and payment is made in
accordance with the foregoing provisions of this Section 2, and the person or
persons in whose name or names the certificates for the Shares shall be issuable
upon such exercise shall become the holder or holders of record of such Shares
at that time and date. The Shares and the certificates for the Shares so
purchased shall be delivered to the Holder within a reasonable time, not
exceeding ten (10) business days, after the rights represented by this Placement
Agent's Warrant shall have been so exercised.

            (b) Notwithstanding anything to the contrary contained in Section
2(a), the Holder may elect to exercise this Placement Agent's Warrant in whole
or in part on a "cashless exercise basis" by receiving Shares equal to the value
(as determined below) of this Placement Agent's Warrant, or any part hereof,
upon surrender of the Placement Agent's Warrant at the principal office of the
Company together with notice of such election in which event the Company shall
issue to the Holder a number of Shares computed using the following formula:

                                 X = Y(A-B)
                                     ------
                                       A

      Where:      X = the number of Shares to be issued to the Holder;

                  Y = the number of Shares issuable upon exercise of this
                      Placement Agent's Warrant or, if only a portion of this
                      Placement Agent's Warrant is being exercised, the portion
                      of this Placement Agent's Warrant being canceled (at the
                      date of such calculation);

                  A = the fair market value of one share of Common Stock (at the
                      date of such calculation);

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                  B = the Exercise Price (as adjusted to the date of such
                      calculation).

For the purpose of any computation under this Subsection 2(b), the fair market
value per share of Common Stock at any date shall be deemed to be the Closing
Price of the Common Stock on the Trading Day immediately preceding the date as
of which the fair market value is being determined, provided that if the Common
Stock is not then listed on any market or exchange, then the fair market value
shall be the average of the closing bid prices for the Common Stock on the OTC
Bulletin Board, or, if such is not available, the Pink Sheets LLC (formerly the
National Quotation Bureau), or otherwise the average of the closing bid prices
for the Common Stock quoted by two market-makers of the Common Stock, or
otherwise such fair market value shall be determined in good faith by the
Corporation and the Holders. "TRADING DAY" shall mean any day on which the
principal United States securities exchange or trading market on which the
Common Stock is listed or traded (the "PRINCIPAL MARKET") as reported by
Bloomberg Financial Markets ("BLOOMBERG'S") is open for trading. "CLOSING PRICE"
shall mean the last sale price for the Common Stock on the Principal Market on
any particular Trading Day.

      3. TRANSFER. (a) The Placement Agent's Warrant shall not be sold,
transferred, assigned, or hypothecated for a period of one (1) year commencing
on the Closing Date, except that it may be transferred to successors of the
Holder.

            (b) Any transfer of this Placement Agent's Warrant shall be effected
by the Holder by (i) executing the form of assignment at the end hereof and (ii)
surrendering the Placement Agent's Warrant for cancellation at the office or
agency of the Company referred to in Section 2 hereof, accompanied by (x) a
written instrument of transfer in form reasonably satisfactory by the Company,
duly executed by the registered Holder thereof or by the duly appointed legal
representative thereof or by a duly authorized attorney-in-fact, (y) a
certificate (signed by an officer of the Holder if the Holder is a corporation)
stating that each transferee is a permitted transferee under this Section 3; and
(z) an opinion of counsel, reasonably satisfactory in form and substance to the
Company, to the effect that this Placement Agent's Warrant or the Shares, as
applicable, may be sold or otherwise transferred without registration under the
Securities Act of 1933, as amended (the "ACT").

            Upon any transfer of this Placement Agent's Warrant or any part
thereof in accordance with the first sentence of this Section 3(b), the Company
shall issue, in the name or names specified by the Holder (including the
Holder), a new Placement Agent's Warrant or Warrants of like tenor and
representing in the aggregate rights to purchase the same number of Shares as
are purchasable hereunder at such time.

            (c) Any attempted transfer of this Placement Agent's Warrant or any
part thereof in violation of this Section 3 shall be null and void ab initio.

      4. SHARES TO BE FULLY PAID; RESERVATION OF SHARES. The Company covenants
and agrees that all Shares which may be purchased hereunder will, upon issuance
and delivery against payment therefor of the requisite purchase price, be duly
and validly issued, fully paid and nonassessable. The Company further covenants
and agrees that, during the periods within which the Placement Agent's Warrant
may be exercised, the Company will at all times have authorized and reserved a
sufficient

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number of shares of its Common Stock to provide for the exercise of the
Placement Agent's Warrant.

      5. NO VOTING OR DIVIDEND RIGHTS. The Placement Agent's Warrant shall not
entitle the Holder to any voting rights or other rights, including without
limitation notice of meetings of other actions or receipt of dividends, as a
stockholder of the Company.

      6. REGISTRATION RIGHTS. The Company covenants and agrees that, during the
periods within which the Placement Agent's Warrant may be exercised, the Company
will, upon the written request of the Placement Agent, use its commercially
reasonable efforts to amend or supplement the registration statement filed on
Form S-3 in connection with the offering of the Common Stock that is subject to
the Placement Agent Agreement in order to include any additional information as,
in the opinion of counsel to the Placement Agent, may be required to permit a
public offering of all or any of the Shares underlying the Placement Agent's
Warrant (the "REGISTRABLE SECURITIES"). In the event that, during any such
periods, the Registrable Securities may not be publicly offered under such
registration statement, the Holders of Placement Agent's Warrants shall have the
following registration rights:

            (a) Except as provided in Section 6(b), the Company shall advise the
Holder or its permitted transferee, whether the Holder holds the Placement
Agent's Warrant or has exercised the Placement Agent's Warrant and holds Shares,
by written notice at least ten (10) business days prior to the filing of any new
registration statement thereto under the Act, covering any equity securities of
the Company, for its own account or for the account of others, except for any
registration statement filed on Form S-4 or S-8 (or other comparable form), and
will, during the four (4) year period beginning on the First Anniversary Date,
upon the request of the Holder, include in any such new registration statement
(the "REGISTRATION STATEMENT") such information as may be required to permit a
public offering of, all or any of the Registrable Securities.

            (b) At any time during the four (4) year period beginning on the
First Anniversary Date, a 50% Holder (as defined below) may request that the
Company register under the Act any and all of the Registrable Securities held by
such 50% Holder, at the Company's expense (except as provided below). Except as
otherwise expressly provided herein, the holders of Registrable Securities may
exercise the demand registration rights provided in this Section 6(b) only on
one occasion. Upon the receipt of any such notice, the Company will promptly,
but no later than four weeks after receipt of such notice, file a post-effective
amendment to any existing registration statement or a new registration statement
pursuant to the Act (such post-effective amendment or new registration
statement, a "DEMAND REGISTRATION Statement"), so that such designated
Registrable Securities may be publicly sold under the Act as promptly as
practicable thereafter and the Company shall, subject to Section 6(h), use its
commercially reasonable efforts to cause such Demand Registration Statement to
become effective (including the taking of such reasonable steps as are necessary
to obtain the removal of any stop order) within 120 days after the receipt of
such notice, provided, that such 50% Holder shall furnish the Company with
appropriate information in connection therewith as the Company may reasonably
request in writing. The 50% Holder may, at its option, request the registration
of any of Registrable Securities in a registration statement made

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by the Company as contemplated by Section 6(a) or in connection with a request
made pursuant to this Section 6(b), in either case prior to acquisition of the
Shares issuable upon exercise of the Placement Agent's Warrant. Subject to
Section 6(h), within ten days after receiving any such notice pursuant to this
Section 6(b), the Company shall give notice to any other Holders of the
Placement Agent's Warrant, advising that the Company is proceeding with such
Demand Registration Statement and offering to include therein, pursuant to
Section 6(a), the Shares underlying that part of the Placement Agent's Warrant
held by the other Holders, provided that they shall furnish the Company with
such appropriate information (relating to the intentions of such Holders) in
connection therewith as the Company shall reasonably request in writing.

            (c) The term "50% HOLDER" as used in this Section 6 shall mean the
Holder(s) of at least 50% of the Placement Agent's Warrant and/or the Shares
underlying the Placement Agent's Warrant upon the initial issuance of the
Placement Agent's Warrant, as the same may have been adjusted pursuant to
Section 8.

            (d) For so long as the Registrable Securities included in any
Registration Statement or Demand Registration Statement remain unsold, but in
any event not longer than 270 days after the date of effectiveness of such
Registration Statement or Demand Registration Statement (plus the number of
days, if any, that such Registration Statement or Demand Registration Statement
has been suspended pursuant to the provisions of Section 6(h)), the Company
shall, subject to Section 6(h), use its commercially reasonable efforts to (i)
maintain the effectiveness of such Registration Statement or Demand Registration
Statement; (ii) timely file all reports required under the Securities Exchange
Act of 1934, as amended, and the rules and regulations of the Securities and
Exchange Commission (the "COMMISSION") thereunder; (iii) file such
post-effective amendments to the Registration Statement or Demand Registration
Statement as may be necessary so that the Registration Statement or Demand
Registration Statement does not contain any misstatement of a material fact or
omit to state any material fact required to make the statements therein not
misleading; (iv) supply prospectuses and such other documents as any Holder
whose Registrable Securities are included in such Registration Statement or
Demand Registration Statement may reasonably request in order to facilitate the
public sale or other disposition of such Registrable Securities; (v) register
and qualify any of the Registrable Securities for sale in such jurisdictions
within the United States (x) as any such Holder designates and (y) with respect
to which the Company obtained a qualification in connection with its initial
public offering, provided that the nothing in this clause (v) shall require the
Company to qualify to do business as a foreign corporation, submit to taxation
in any jurisdiction or to file a general consent to service of process in any
jurisdiction in which it is not otherwise so qualified or required to file such
a consent at the time; and (vi) do any and all other acts and things which may
be necessary or desirable to enable any such Holder to consummate the public
sale or other disposition of the Registrable Securities included in the
Registration Statement or Demand Registration Statement, all at no expense to
such Holder or the Placement Agent (except as provided in the immediately
following sentence). All costs and expenses in connection with any Registration
Statement or Demand Registration Statement shall be borne by the Company, except
that the Holder(s) shall bear the fees of their own counsel and any other
advisors retained by them and any underwriting discounts or sales or other
commissions applicable to any of the Registrable

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Securities sold by them. In connection with any Registration Statement or Demand
Registration Statement, the Company shall furnish indemnification in the manner
provided in Section 7 hereof, and each Holder whose Registrable Securities are
included therein shall furnish information and indemnification in the manner
provided in Section 7. Subject to Section 6(g), the Company shall have the right
to include additional shares of Common Stock to be issued and sold by the
Company in any Demand Registration Statement.

            (e) Notwithstanding the foregoing set forth in this Section 6, the
Company shall not be required to include in any Registration Statement or any
Demand Registration Statement any Registrable Securities which in the opinion of
counsel to the Company (which opinion is reasonably acceptable to counsel to the
Placement Agent) would be saleable without restriction or limitation under the
holding period requirements or volume limitations under Rule 144 (or its
successor) if the Placement Agent's Warrant was exercised pursuant to Section
2(b) herein.

            (f) If any registration pursuant to this Section 6 is in the form of
an underwritten offering, the Company will select and obtain the investment
banker or investment bankers and manager or managers that will administer the
offering. The Company shall (together with each Holder whose Registrable
Securities are included in such offering) enter into an underwriting agreement
in customary form with the managing underwriter selected for such underwriting.
If any Holder disapproves of the terms of the underwriting, it may elect to
withdraw therefrom by written notice to the Company and the managing
underwriter, and upon such withdrawal the original request of such Holder to
cause Registrable Securities to be registered shall not be deemed to constitute
a request for registration pursuant to Section 6(b), provided that the
withdrawal of one or more Holders shall not affect the determination of whether
any request made pursuant to Section 6(b) was made by a 50% Holder, and provided
further that if all Holders who have requested inclusion of their shares in a
Demand Registration pursuant to Section 6(b) withdraw their Registrable
Securities, then, notwithstanding anything to the contrary in this Placement
Agent's Warrant, any Holders who request registration of Registrable Securities
pursuant to Section 6(b) in the future shall be responsible for and pay all
expenses incurred by the Company in connection with such future registration.

            (g) (i) In the event that any registration pursuant to Section 6(a)
shall be in connection with an underwritten offering, and the managing
underwriter determines in good faith and advises in writing that the number of
Registrable Securities to be included in such offering, together with the number
of shares of Common Stock to be included in the Registration Statement by the
Company or other holders of the Company's securities with the right to request
inclusion in the Registration Statement, if any, exceeds the number of shares of
Common Stock that it is advisable to offer and sell at such time or would
interfere with the successful marketing of the Common Stock covered by the
Registration Statement, then priority for including shares of Common Stock in
the Registration Statement, up to the number advised by the managing
underwriter, shall be allocated first, to the Company and each other person who
has requested inclusion of shares of Common Stock pursuant to a "demand"
registration right, pro rata in proportion to the respective number of shares of
Common Stock to be included by them, and second, to the extent of any remaining
capacity as advised by the

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managing underwriter, to the Holders requesting registration of their
Registrable Securities and each other person who has requested inclusion of
shares of Common Stock pursuant to a "piggyback" registration right, pro rata in
proportion to the respective number of shares of Common Stock (including
Registrable Securities) to be included by them. (ii) In the event that any
registration pursuant to Section 6(b) shall be in connection with an
underwritten offering, and the managing underwriter determines in good faith and
advises in writing that the number of Registrable Securities to be included in
such offering, together with the number of shares of Common Stock to be included
in the Demand Registration Statement by the Company or other holders of the
Company's securities with the right to request inclusion in the Demand
Registration Statement, if any, exceeds the number of shares of Common Stock
that it is advisable to offer and sell at such time or would interfere with the
successful marketing of the Common Stock covered by the Demand Registration
Statement, then priority for including shares of Common Stock in the Demand
Registration Statement, up to the number advised by the managing underwriter,
shall be allocated first, to the 50% Holder and each other person who has
requested inclusion of shares of Common Stock pursuant to a "demand"
registration right, pro rata in proportion to the respective number of shares of
Common Stock to be included by them, and second, to the extent of any remaining
capacity as advised by the managing underwriter, to the Company and each other
person (including any Holder who is not a 50% Holder and who requests inclusion
of Registrable Securities in the Demand Registration Statement pursuant to
Section 6(a)) who has requested inclusion of shares of Common Stock pursuant to
a "piggyback" registration right, pro rata in proportion to the respective
number of shares of Common Stock (including Registrable Securities) to be
included by them.

            (h) In any registration initiated by the Company or by any person
having "demand" registration rights (other than a 50% Holder exercising such
rights pursuant to Section 6(b)) in which Holders request inclusion of their
Registrable Securities pursuant to Section 6(a), if at any time after giving
notice of its intention to register securities and prior to the effective date
of the Registration Statement the Company or such other person shall determine
for any reason not to register or to delay registration of it securities, the
Company may, at its election, give written notice of such determination to each
Holder that has requested inclusion of Registrable Securities in the
Registration Statement and (x) in the case of a determination not to register,
shall be relieved of its obligation to register any Registrable Securities in
connection with such registration and (y) in the case of a determination to
delay registering, shall be permitted to delay registering any Registrable
Securities for the same period as the delay in registering such other
securities. If (i) at any time when a prospectus relating to Registrable
Securities is required to be delivered under the Act, the Company discovers
that, or any event occurs as a result of which, the prospectus (including any
supplement thereto) included in any Registration Statement or Demand
Registration Statement, as then in effect, includes an untrue statement of a
material fact or omits to state any material fact required to be stated therein
or necessary to make the statements therein, in the light of the circumstances
under which they were made, not misleading, or (ii) the Commission issues any
stop order suspending the effectiveness of any Registration Statement or
proceedings are initiated or threatened for that purpose, then the Company shall
promptly deliver a written notice to such effect to each Holder whose
Registrable

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Securities are included in such Registration Statement or Demand Registration
Statement, and each such Holder shall immediately upon receipt of such notice
discontinue its disposition of Registrable Securities pursuant to such
Registration Statement or Demand Registration Statement until its receipt of the
copies of the supplemented or amended prospectus contemplated by the immediately
following sentence and, if so directed by the Company, shall deliver to the
Company (at the Company's expense) all copies, other than permanent file copies,
then in such Holder's possession of the prospectus or prospectus supplement
relating to such Registrable Securities current at the time of receipt of such
notice. As promptly as practicable following the event or discovery referred to
in clause (i) of the immediately preceding sentence, the Company shall prepare
and furnish to the Holders whose Registrable Securities are included in such
Registration Statement or Demand Registration Statement a reasonable number of
copies of an amendment or supplement of such prospectus so that, as thereafter
delivered to purchasers of such Registrable Securities, such prospectus shall
not include an untrue statement of a material fact or omit to state a material
fact required to be stated therein or necessary to make the statements therein,
in the light of the circumstances under which they were made, not misleading.
Notwithstanding anything to the contrary in this Section 6 if the filing or
maintenance of any Registration Statement or Demand Registration Statement would
require the Company to make a disclosure that would, in the reasonable judgment
of the Company's Board of Directors, have a material adverse effect on the
business, operations, properties, prospects or financial condition of the
Company or on pending or imminent transactions, the Company shall have the
right, exercisable for a period not to exceed in the aggregate 60 consecutive
calendar days in any period of twelve consecutive months (the "Blackout Period")
upon written notice to the Holders, to delay the filing of any Registration
Statement or Demand Registration Statement or of any amendment thereto, to
suspend its obligation to maintain the effectiveness of any Registration
Statement or Demand Registration Statement and to suspend the use of any
prospectus or prospectus supplement in connection with any Registration
Statement or Demand Registration Statement. Each Holder agrees that upon receipt
of any such notice from the Company, it shall immediately cease all efforts to
dispose of Registrable Securities pursuant to such Registration Statement or
Demand Registration Statement until such time as the Company shall notify it of
the end of such restrictions or, if earlier, the expiration of the Blackout
Period.

            7. INDEMNIFICATION. (a) Whenever pursuant to Section 6 a
Registration Statement or Demand Registration Statement relating to any Shares
issued upon exercise of the Placement Agent's Warrant is filed under the Act,
amended or supplemented, the Company will indemnify and hold harmless each
Holder of the securities covered by such Registration Statement or Demand
Registration Statement, amendment or supplement (such Holder being hereinafter
called the "DISTRIBUTING HOLDER"), and each person, if any, who controls (within
the meaning of the Act) the Distributing Holder, and each underwriter (within
the meaning of the Act) of such securities and each person, if any, who controls
(within the meaning of the Act) any such underwriter, against any losses,
claims, damages or liabilities, joint or several, to which the Distributing
Holder, any such controlling person or any such underwriter may become subject,
under the Act or otherwise, insofar as such losses, claims, damages or
liabilities, or actions in respect thereof, arise out of or are based upon (i)
any untrue statement or alleged untrue

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statement of any material fact contained in any such Registration Statement or
Demand Registration Statement as declared effective or any final prospectus
constituting a part thereof or any amendment or supplement thereto, (ii) the
omission or the alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein not misleading or
(iii) any act or failure to act, or any alleged act or failure to act, by any
Distributing Holder in connection with, or relating in any manner to, the
Registration Statement or Demand Registration Statement or the offering
contemplated thereby, and which is included as part of or referred to in any
loss, claim, damage, liability or action arising out of or based upon matters
covered by clause (i) or (ii) above; (provided that the Company shall not be
liable in the case of any matter covered by this clause (iii) to the extent that
it is determined in a final judgment by a court of competent jurisdiction that
such loss, claim, damage, liability or action resulted directly from any such
act or failure to act undertaken or omitted to be taken by such Distributing
Holder through its gross negligence or willful misconduct) and will reimburse
the Distributing Holder or such controlling person or underwriter promptly upon
demand for any legal or other expense reasonably incurred by them in connection
with investigating or defending any such loss, claim, damage, liability or
action as such expenses are incurred; provided, however, that the Company will
not be liable in any such case to the extent that any such loss, claim, damage,
liability or action arises out of or is based upon an untrue statement or
alleged untrue statement or omission or alleged omission made in said
Registration Statement or Demand Registration Statement, said preliminary
prospectus, said final prospectus or said amendment or supplement in reliance
upon and in conformity with written information furnished by such Distributing
Holder or any other Distributing Holder for use in the preparation thereof and
provided further, that the indemnity agreement provided in this Section 7(a)
with respect to any preliminary prospectus shall not inure to the benefit of any
Distributing Holder, controlling person of such Distributing Holder, underwriter
or controlling person of such underwriter from whom the person asserting any
losses, claims, charges, liabilities or litigation based upon any untrue
statement or alleged untrue statement of a material fact or omission or alleged
omission to state therein a material fact, received such preliminary prospectus,
if a copy of the prospectus in which such untrue statement or alleged untrue
statement or omission or alleged omission was corrected has not been sent or
given to such person within the time required by the Act and the rules and
regulations of the Commission thereunder. This indemnity agreement is not
exclusive and will be in addition to any liability, which the Company might
otherwise have and shall not limit any rights or remedies that may otherwise be
available at law or in equity to each Distributing Holder.

            (b) The Distributing Holder will indemnify and hold harmless the
Company, each of its directors, each of its officers who have signed said
Registration Statement or Demand Registration Statement and such amendments and
supplements thereto, and each person, if any, who controls the Company (within
the meaning of the Act) against any losses, claims, damages or liabilities,
joint or several, to which the Company or any such director, officer or
controlling person may become subject, under the Act or otherwise, insofar as
such losses, claims, damages or liabilities, or actions in respect thereof,
arise out of or are based upon (i) any untrue or alleged untrue statement of any
material fact contained in said Registration Statement or Demand Registration

                                       9
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Statement, said preliminary prospectus, said final prospectus, or said amendment
or supplement, or (ii) are based upon the omission or the alleged omission to
state therein a material fact required to be stated therein or necessary to make
the statements therein not misleading, in each case to the extent, but only to
the extent, that such loss, claim, damage or liability arises out of or is based
upon an untrue statement or alleged untrue statement or omission or alleged
omission made in said Registration Statement or Demand Registration Statement,
said preliminary prospectus, said final prospectus or said amendment or
supplement in reliance upon and in conformity with written information furnished
by such Distributing Holder for use in the preparation thereof; and will
reimburse the Company or any such director, officer or controlling person for
any legal or other expenses reasonably incurred by them in connection with
investigating or defending any such loss, claim, damage, liability or action as
such expenses are incurred. This indemnity agreement is not exclusive and will
be in addition to any liability, which each Distributing Holder might otherwise
have and shall not limit any rights or remedies that may otherwise be available
at law or in equity to the Company.

            (c) Promptly after receipt by an indemnified party under this
Section 7 of notice of the commencement of any action, such indemnified party
will, if a claim in respect thereof is to be made against an indemnifying party
under this Section 7, notify the indemnifying party in writing of the
commencement thereof, but the omission so to notify the indemnifying party will
not relieve it from any liability which it may have to any indemnified party for
indemnity or contribution to the extent it is not prejudiced as a proximate
result of such failure. In case any such action is brought against any
indemnified party, and such indemnified party seeks or intends to seek indemnity
from an indemnifying party, the indemnifying party will be entitled to
participate in, and, to the extent that it shall elect, jointly with any other
indemnifying party similarly notified, by written notice delivered to the
indemnified party promptly after receiving the aforesaid notice from such
indemnified party, to assume the defense thereof with counsel reasonably
satisfactory to such indemnified party; provided, however, if the defendants in
any such action include both the indemnified party and the indemnifying party
and the indemnified party shall have reasonably concluded that a conflict may
arise between the positions of the indemnifying party and the indemnified party
in conducting the defense of any such action or that there may be legal defenses
available to it and/or other indemnified parties which are different from or
additional to those available to the indemnifying party, the indemnified party
or parties shall have the right to select separate counsel to assume such legal
defenses and to otherwise participate in the defense of such action on behalf of
such indemnified party or parties. Upon receipt of notice from the indemnifying
party to such indemnified party of such indemnifying party's election so to
assume the defense of such action and approval by the indemnified party of
counsel (which approval shall not be unreasonably withheld or delayed), the
indemnifying party will not be liable to such indemnified party under this
Section 7 for any legal or other expenses subsequently incurred by such
indemnified party in connection with the defense thereof unless: (i) the
indemnified party shall have employed separate counsel in accordance with the
proviso to the next preceding sentence (it being understood, however, that the
indemnifying party shall not be liable for the expenses of more than one
separate counsel (together with local counsel), representing the indemnified
parties who are parties to such action); (ii) the indemnifying party shall not
have employed counsel

                                       10
<PAGE>

satisfactory to the indemnified party to represent the indemnified party within
a reasonable time after notice of commencement of the action; or (iii) the
indemnifying party has authorized the employment of counsel for the indemnified
party satisfactory to the indemnified party at the expense of the indemnifying
party, in each of which cases the fees and expenses of counsel shall be at the
expense of the indemnifying party.

            (d) The indemnifying party under this Section 7 shall not be liable
for any settlement of any proceeding effected without its written consent, which
consent shall not be unreasonably withheld or delayed, but if settled with such
consent or if there be a final judgment for the plaintiff, the indemnifying
party agrees to indemnify the indemnified party against any loss, claim, damage,
liability or expense by reason of such settlement or judgment. No indemnifying
party shall, without the prior written consent of the indemnified party, effect
any settlement, compromise or consent to the entry of judgment in any pending or
threatened action, suit or proceeding in respect of which any indemnified party
is or could have been a party and indemnity was or could have been sought
hereunder by such indemnified party, unless such settlement, compromise or
consent includes: (i) an unconditional release of such indemnified party from
all liability on claims that are the subject matter of such action, suit or
proceeding; and (ii) does not include a statement as to or an admission of
fault, culpability or a failure to act by or on behalf of any indemnified party.

            (e) Any losses, claims, damages, liabilities or expenses for which
an indemnified party is entitled to indemnification or contribution under this
Section 7 shall be paid by the indemnifying party to the indemnified party as
such losses, claims, damages, liabilities or expenses are incurred, but in all
cases, no later than forty-five (45) days after invoice to the indemnifying
party.

            (f) If the indemnification provided for in this Section 7 is
unavailable to or insufficient to hold harmless an indemnified party under
Section 7(a) or 7(b) above in respect of any losses, claims, damages or
liabilities (or actions or proceedings in respect thereof) then each
indemnifying party shall contribute to the aggregate amount paid or payable by
such indemnified party in such proportion as is appropriate to reflect the
relative fault of such indemnifying party on the one hand and the Distributing
Holder on the other in connection with the statements or omissions which
resulted in such losses, claims, damages or liabilities (or actions or
proceedings in respect thereof), as well as any other relevant equitable
considerations. The relative fault shall be determined by reference to, among
other things, whether the untrue or alleged untrue statement of a material fact
or the omission or alleged omission to state a material fact relates to
information supplied by the Company or the "control" stockholders on the one
hand or the Distributing Holder on the other and the parties' relative intent,
knowledge, access to information and opportunity to correct or prevent such
statement or omission.

      The Company and each Distributing Holder agree that it would not be just
and equitable if contributions pursuant to this Section 7(f) were determined by
pro rata allocation or by any other method of allocation which does not take
account of the equitable considerations referred to above in this Section 7(f).
The amount paid or payable by an indemnified party as a result of the losses,
claims, damages or liabilities (or actions or proceedings in respect thereof)
referred to above in this Section 7(f) shall be deemed to include any legal or
other expenses reasonably incurred by such indemnified

                                       11
<PAGE>

party in connection with investigating or defending any such action or claim.
Notwithstanding the provisions of this Section 7(f): (i) each Distributing
Holder shall not be required to contribute any amount in excess of the amount of
proceeds received by such Holder from sale(s) of such Holder's Shares pursuant
to the Registration Statement or Demand Registration Statement; and (ii) no
person guilty of fraudulent misrepresentation (within the meaning of Section
11(f) of the Act) shall be entitled to contribution from any person who was not
guilty of such fraudulent misrepresentation.

      8. ADJUSTMENT OF EXERCISE PRICE. The Exercise Price in effect at the time
and the number and kind of securities purchasable upon the exercise of the
Warrant shall be subject to adjustment from time to time upon the happening of
certain events as follows:

            (a) In case the Company shall (i) declare a dividend or make a
distribution on its outstanding shares of Common Stock in shares of Common
Stock, (ii) subdivide or reclassify its outstanding shares of Common Stock into
a greater number of shares, (iii) combine or reclassify its outstanding shares
of Common Stock into a smaller number of shares, or (iv) enter into any
transaction whereby the outstanding shares of Common Stock of the Company are at
any time changed into or exchanged for a different number or kind of shares or
other security of the Company or of another corporation through reorganization,
merger, consolidation, liquidation or recapitalization, then appropriate
adjustments in the number of Shares (or other securities for which such Shares
have previously been exchanged or converted) subject to this Placement Agent's
Warrant shall be made and the Exercise Price in effect at the time of the record
date for such dividend or distribution or of the effective date of such
subdivision, combination, reclassification, reorganization, merger,
consolidation, liquidation or recapitalization shall be proportionately adjusted
so that the Holder of this Placement Agent's Warrant exercised after such date
shall be entitled to receive the aggregate number and kind of shares of Common
Stock which, if this Placement Agent's Warrant had been exercised by such Holder
immediately prior to such date, the Holder would have been entitled to receive
upon such dividend, distribution, subdivision, combination, reclassification,
reorganization, merger, consolidation, liquidation or recapitalization. For
example, if the Company declares a 2 for 1 stock distribution and the Exercise
Price hereof immediately prior to such event was $7.00 per Share and the number
of Shares issuable upon exercise of this Placement Agent's Warrant was 85,500,
the adjusted Exercise Price immediately after such event would be $3.50 per
Share and the adjusted number of Shares issuable upon exercise of this Placement
Agent's Warrant would be 171,000. Such adjustment shall be made successively
whenever any event listed above shall occur.

            (b) Whenever the Exercise Price is adjusted, as herein provided, the
Company shall promptly cause a notice setting forth the adjusted Exercise Price
and adjusted number of Shares issuable upon exercise of the Placement Agent's
Warrant to be mailed to the Holder, at its address set forth herein, and shall
cause a certified copy thereof to be mailed to the Company's transfer agent, if
any. The Company may retain a firm of independent certified public accountants
selected by the Board of Directors (who may be the regular accountants employed
by the Company) to make any computation required by this Section 8, and a
certificate signed by such firm shall be conclusive evidence of the correctness
of such adjustment.

                                       12
<PAGE>

            (c) In the event that at any time, as a result of an adjustment made
pursuant to the provisions of this Section 8, the Holder of the Placement
Agent's Warrant thereafter shall become entitled to receive any shares of the
Company other than Common Stock, thereafter the number of such other shares so
receivable upon exercise of the Placement Agent's Warrant shall be subject to
adjustment from time to time in a manner and on terms as nearly equivalent as
practicable to the provisions with respect to the Common Stock contained in
Sections 8(a) above.

      9. GOVERNING LAW. This Agreement shall be governed by and in accordance
with the laws of the State of New York without regard to conflicts of laws
principles thereof.

      10. BINDING EFFECT ON SUCCESSORS. In case of any consolidation of the
Company with, or merger of the Company into, any other entity, or in case of any
sale or conveyance of all or substantially all of the assets of the Company
other than in connection with a plan of complete liquidation of the Company at
any time prior to the Expiration Date, then as a condition of such
consolidation, merger or sale or conveyance, the Company shall give written
notice of consolidation, merger, sale or conveyance to the Holder and, from and
after the effective date of such consolidation, merger, sale or conveyance the
Placement Agent's Warrant shall represent only the right to receive the
consideration that would have been issuable in respect of the Shares underlying
the Placement Agent's Warrant in such consolidation, merger, sale or conveyance
had the Placement Agent's Warrant been exercised in full immediately prior to
such effective time and the Holder shall have no further rights under this
Placement Agent's Warrant other than the right to receive such consideration.

      11. FRACTIONAL SHARES. No fractional shares shall be issued upon exercise
of this Placement Agent's Warrant. The Company shall, in lieu of issuing any
fractional share, pay the holder entitled to such fraction a sum in cash equal
to such fraction multiplied by the then effective Exercise Price.

      12. LOST WARRANTS. The Company represents and warrants to the Holder
hereof that upon receipt of evidence reasonably satisfactory to the Company of
the loss, theft, destruction, or mutilation of this Warrant and, in the case of
any such loss, theft or destruction, upon receipt of an indemnity reasonably
satisfactory to the Company, or in the case of any such mutilation upon
surrender and cancellation of such Warrant, the Company, at its expense, will
make and deliver a new Warrant, of like tenor, in lieu of the lost, stolen,
destroyed or mutilated Warrant.

      13. HEADINGS. The headings of the several sections and paragraphs of this
Warrant are inserted for convenience only and do not constitute a part of this
Warrant.

      14. MODIFICATION AND WAIVER. This Warrant and any provision hereof may be
changed, waived, discharged or terminated only by an instrument in writing
signed by the party against which enforcement of the same is sought.

      15. SURVIVAL. The rights and obligations of the Company, of the holder of
this Warrant and of the holder of Shares issued upon exercise of this Warrant
shall survive the exercise of this Warrant.

                                       13
<PAGE>

      IN WITNESS WHEREOF, the Company has caused this Placement Agent's Warrant
to be signed by its duly authorized officers under its corporate seal, and this
Placement Agent's Warrant to be dated May 18, 2004.

                                         NORTHFIELD LABORATORIES INC.

                                         By:______________________________
                                             Name:
                                             Title:

                                       14
<PAGE>

                                  PURCHASE FORM

                  (To be signed only upon exercise of Warrant)

      The undersigned, the holder of the foregoing Placement Agent's Warrant,
hereby irrevocably elects to exercise the purchase rights represented by such
Warrant for, and to purchase thereunder, _______________ shares of Common Stock,
$0.01 par value per share (the "SHARES"), of NORTHFIELD LABORATORIES INC. and
either

[ ] tenders herewith payment of the aggregate Exercise Price in respect of the
Shares in full, in the amount of $_________; or

[ ] elects pursuant to Section 2(b) of such Warrant to convert such Warrant into
Common Stock on a cashless exercise basis; and

      requests that the certificates for the Shares issued in the name(s) of,
and delivered to _________________, whose address(es) is (are):

      Dated:__________________________

                        By: __________________________

                            __________________________

                            __________________________
                            Address

<PAGE>

                                  TRANSFER FORM

         (To be signed only upon transfer of Placement Agent's Warrant)

      For value received, the undersigned hereby sells, assigns, and transfers
unto ______________________________ the right to purchase Shares represented by
the foregoing Placement Agent's Warrant to the extent of __________ Shares, and
appoints _________________________ attorney to transfer such rights on the books
of Northfield Laboratories Inc., with full power of substitution in the
premises. The undersigned believes that each transferee is a permitted
transferee under Section 3 of the Placement Agent's Warrant.

      Dated: ____________________________

                  By:       __________________________

                            __________________________

                            __________________________
                            Address

In the presence of:

__________________________