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                                                                    Exhibit 31.1

                                  CERTIFICATION

I, James R. Gavin III, M.D., Ph.D., certify that:

1. I have reviewed this Annual Report on Form 10-KSB of MicroIslet, Inc.;

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 small business
issuer as of, and for, the periods presented in this report;

4. The small business issuer's other certifying officer(s) 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
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,
     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 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 report based on
     such evaluation; and

            (c) Disclosed in this 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 (the small business
     issuer's fourth fiscal quarter in the case of an annual report) 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(s) 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
the 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: April 6, 2006

                                   /s/ James R. Gavin III
                                   ---------------------------------------------
                                   James R. Gavin III, M.D., Ph.D.
                                   Interim President and Chief Executive Officer