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                                                                    EXHIBIT 31.1


                                  CERTIFICATION

I, Steven A. Gould, M.D., Chief Executive Officer, certify that:

1.   I have reviewed this report on Form 10-Q/A of Northfield Laboratories Inc.
     (the "Registrant");

2.   Based on my knowledge, this report does not contain any untrue statement of
     a material fact or omit to state a material fact necessary to make the
     statements made, in light of the circumstances under which such statements
     were made, not misleading with respect to the period covered by this
     report;

3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations and cash flows of
     the Registrant as of, and for, the periods presented in this report;

4.   The Registrant's other certifying officer and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in Exchange Act Rules 13a-15e and 15d-15e for the Registrant and have:

     a. Designed such disclosure controls and procedures, or caused such
        disclosure controls and procedures to be designed under our supervision,
        to ensure that material information relating to the Registrant,
        including its consolidated subsidiaries, is made known to us by others
        within those entities, particularly during the period in which this
        quarterly report is being prepared;

     b. Evaluated the effectiveness of the Registrant's disclosure controls and
        procedures and presented in this report our conclusions about the
        effectiveness of the disclosure controls and procedures, as of the end
        of the period covered by this report based on such evaluation; and

     c. Disclosed in this report any change in the Registrant's internal control
        over financial reporting that occurred during the Registrant's most
        recent fiscal quarter that has materially affected, or is reasonably
        likely to materially affect, the Registrant's internal control over
        financial reporting; and

5.   The Registrant's other certifying officer and I have disclosed, based on
     our most recent evaluation of internal control over financial reporting, to
     the Registrant's auditors and the audit committee of Registrant's Board of
     Directors:

     a. all significant deficiencies and material weaknesses in the design or
        operation of internal control over financial reporting which are
        reasonably likely to adversely affect the Registrant's ability to
        record, process, summarize and report financial information; and

     b. any fraud, whether or not material, that involves management or other
        employees who have a significant role in the Registrant's internal
        control over financial reporting.


Date: October 20, 2003                              /s/ Steven A. Gould, M.D.
                                                    ----------------------------
                                                    Steven A. Gould, M.D.
                                                    Chief Executive Officer