**Exhibit 31.1****Certification of the Principal Executive Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002**I, Douglas D. Burkett, certify that:1. I have reviewed this report on Form 10-Q for the quarter ended October 31, 2005 of Zila, Inc.;2. Based on my knowledge, this report for the quarter ended October 31, 2005 does not containany untrue statement of a material fact or omit to state a material fact necessary to make thestatements made, in light of the circumstances under which such statements were made, notmisleading with respect to the period covered by this report;3. Based on my knowledge, the financial statements, and other financial information included inthis quarterly report, fairly present in all material respects the financial condition, results ofoperations 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 maintainingdisclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) andinternal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and15d-15(f)) for the registrant and have:     a) designed such disclosure controls and procedures, or caused such disclosurecontrols and procedures to be designed under our supervision, to ensure thatmaterial information relating to the registrant, including its consolidatedsubsidiaries, is made known to us by others within those entities, particularlyduring the period in which this report is being prepared;     b) designed such internal control over financial reporting, or caused suchinternal control over financial reporting to be designed under our supervision,to provide reasonable assurance regarding the reliability of financialreporting and the preparation of financial statements for external purposes inaccordance with generally accepted accounting principles;     c) evaluated the effectiveness of the registrant’s disclosure controls andprocedures and presented in this report our conclusions about the effectivenessof the disclosure controls and procedures, as of the end of the period coveredby this report based on such evaluation; and     d) disclosed in this report any change in the registrant’s internal controlover financial reporting that occurred during the registrant’s most recentfiscal quarter that has materially affected, or is reasonably likely tomaterially affect, the registrant’s internal control over financial reporting;5. The registrant’s other certifying officer and I have disclosed, based on our most recentevaluation of internal control over financial reporting, to the registrant’s auditors and the auditcommittee of registrant’s board of directors (or persons performing the equivalent functions):     a) all significant deficiencies and material weaknesses in the design oroperation of internal control over financial reporting which are reasonablylikely 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 otheremployees who have a significant role in the registrant’s internal controlsover financial reporting./s/ Douglas D. Burkett, Ph. D.