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                                                                    Exhibit 31.1


                            CERTIFICATION PURSUANT TO
                                 SECTION 302 OF
                         THE SARBANES-OXLEY ACT OF 2002

I, Kenneth J. Zuerblis, certify that:

    1.   I have reviewed this Quarterly Report on Form 10-Q for the quarter
         ended September 30, 2004 of Enzon Pharmaceuticals, Inc. ("Enzon");
    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-15(e) and
         15d-15(e)) 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 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 (the
                 registrant's fourth fiscal quarter in the case of an
                 annual report) 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 the registrant's board of directors (or persons
         performing the equivalent functions):
             (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.

November 15, 2004

                                           By: /s/Kenneth J. Zuerblis
                                              -----------------------
                                           Executive Vice President Finance,
                                           Chief Financial Officer and
                                           (Principal Accounting Officer and
                                           Acting Principal Executive Officer)
                                           Corporate Secretary


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