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Exhibit 31.1


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


I, Thomas G. Tachovsky, certify that:

1. I have reviewed this quarterly report on Form 10-QSB of Entropin, Inc.;

2. Based on my knowledge, this quarterly 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 quarterly
report;

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

4. The small business issuer'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 small business issuer and
we 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 small
         business issuer, is made known to us by others within this entity,
         particularly during the period in which this quarterly report is being
         prepared;

         (b) evaluated the effectiveness of the small business issuer'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 quarterly
         report based on such evaluation; and

         (c) disclosed in this quarterly report any change in the small business
         issuer's internal control over financial reporting that occurred during
         the small business issuer's most recent fiscal quarter that has
         materially affected, or is reasonably likely to materially affect, the
         small business issuer's internal control over financial reporting; and

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


Date: August 12, 2003


/s/ Thomas G. Tachovsky, Ph.D.
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Thomas G. Tachovsky, Ph.D.
President and Chief Executive Officer