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                                                                     EXHIBIT 3-D

               CERTIFICATE OF DESIGNATION, PREFERENCES AND RIGHTS
                                       OF
                      SERIES B CONVERTIBLE PREFERRED STOCK
                                       OF
                                   ZILA, INC.

                         Pursuant to Section 151 of the
                           General Corporation Law of
                              the State of Delaware

         The President of Zila, Inc. (hereinafter called the "Corporation"), a
corporation organized and existing under the General Corporation Law of the
State of Delaware, in accordance with the provisions of Section 151, does hereby
certify as follows:

         Pursuant to the authority conferred upon the Board of Directors of the
Corporation by the Certificate of Incorporation of the Corporation, the Board of
Directors of the Corporation on December 7, 2000, adopted the following
resolution creating a series of Preferred Stock designated as Series B Preferred
Stock:

         RESOLVED, that pursuant to the authority granted to the Board of
Directors in accordance with the provisions of the Corporation's Certificate of
Incorporation, as amended, the Board of Directors hereby authorizes a series of
the Corporation's previously authorized Preferred Stock, par value $0.001 per
share (the "Preferred Stock"), and hereby states the designation and number of
shares, and fixes the relative rights, preferences, privileges and restrictions
thereof as follows:

1.       DESIGNATION AND AMOUNT.

         The number of shares of Preferred Stock that shall be designated as the
Series B Convertible Preferred Stock (the "Series B Preferred Stock") shall be
100,000.

2.       DIVIDENDS.

         (a) Cumulative Dividends. The holders of the Series B Preferred Stock
shall be entitled to receive dividends at the rate of $0.0975 per share (as
adjusted for any stock dividends, combinations or splits with respect to such
shares) per fiscal quarter ($0.39 per share per annum), payable out of funds
legally available therefor. Such dividends shall be cumulative and shall be due
and payable quarterly in arrears.

         (b) Preference. No dividends shall be paid on any Common Stock of the
Corporation during any fiscal year of the Corporation until dividends in the
total amount of $0.39 per share (as adjusted for any stock dividends,
combinations or splits with respect to such shares) on the Series
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B Preferred Stock shall be paid or declared and set apart during the fiscal year
and any prior years which dividends accumulated but remain unpaid.

3.       LIQUIDATION PRIORITY.

         Upon the occurrence of (a) any insolvency or bankruptcy proceedings, or
any receivership, liquidation, reorganization or other similar proceedings in
connection therewith, commenced by the Corporation or by its creditors, as such,
or relating to its assets, or (b) the dissolution or other winding up of the
Corporation whether total or partial, whether voluntary or involuntary and
whether or not involving insolvency or bankruptcy proceedings, or (c) any
assignment for the benefit of creditors or any marshaling of the material assets
or material liabilities of the Corporation (each, a "Liquidation Event"), no
distribution shall be made to the holders of any Common Stock unless and until
each holder of Series B Preferred Stock (each, a "Holder" and collectively, the
"Holders") shall have received a Liquidation Preference of $6.50 per share of
Series B Preferred Stock (the "Liquidation Preference"). In the event that upon
the occurrence of a Liquidation Event, the assets available for distribution to
the Holders are insufficient to pay the Liquidation Preference with respect to
all of the outstanding Series B Preferred Stock, the entire assets of the
Corporation shall be distributed ratably among the shares of Series B Preferred
Stock, and such pro rata amount shall be deemed to be the Liquidation
Preference.

4.       REDEMPTION.

         (a) Corporation's Optional Redemption. The Corporation may at any time
after the Redemption Triggering Event (defined below) redeem, from any source of
funds legally available, the Series B Preferred Stock. The Corporation shall
effect such redemption by giving Notice (defined below) to the holders of Series
B Preferred Stock and paying in cash in exchange for the shares of Series B
Preferred Stock to be redeemed a sum equal to the per share Redemption Price
(defined below) plus all accumulated but unpaid dividends on such shares. The
"Redemption Triggering Event" shall be the occurrence hereafter of any ten (10)
trading day period during which the Common Stock of the Corporation maintains a
closing price on each such trading day that is equal to or greater than $9.00
per share. The "Redemption Price" shall be the average bid closing price of the
Common Stock of the Corporation for the five (5) trading days immediately
preceding the date on which the Corporation gives Notice.

         (b) Redemption Notice. At least ten (10) days prior to redemption,
notice shall be sent to each holder of record (at the close of business on the
business day next preceding the day on which notice is given) of the Series B
Preferred Stock to be redeemed, at the address last shown on the records of the
Corporation for such holder, notifying such holder of the redemption to be
effected, specifying the number of shares to be redeemed from such holder, the
redemption, date, the redemption price, the place at which payment may be
obtained and calling upon such holder to surrender to the Corporation, in the
manner and at the place designated, his certificate or certificates representing
the shares to be redeemed (the "Notice"). On or after the redemption date, each
holder of Series B Preferred Stock to be redeemed shall surrender to this
Corporation the certificate or

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certificates representing such shares, in the manner and at the place designated
in the Notice, and thereupon the redemption price of such shares shall be
payable to the order of the person whose name appears on such certificate or
certificates as the owner thereof and each surrendered certificate shall be
cancelled. If less than all shares represented by any such certificate are
redeemed, a new certificate shall be issued representing the unredeemed shares.

         (c) Redemption Date. From and after the redemption date, unless there
shall have been a default in payment of the redemption price, all rights of the
holders of shares of Series B Preferred Stock designated for redemption in the
Notice as holders of Series B Preferred Stock shall cease with respect to such
shares, and such shares shall not thereafter be transferred on the books of the
Corporation or be deemed to be outstanding for any purpose whatsoever. The
shares of Series B Preferred Stock not redeemed shall remain outstanding and
entitled to all the rights and preferences provided herein.

5.       CONVERSION.

         The holders of the Series B Preferred Stock shall have conversion
rights as follows (the "Conversion Rights"):

         (a) Right to Convert. Each share of Series B Preferred Stock shall be
convertible, at the option of the holder thereof, at any time on or before
December 31, 2010 into fully paid and nonassessable shares of Common Stock at
the ratio of one-to-one. A holder may convert his Series B Preferred Stock in
whole or in part, provided that any conversion in part may only be effected in
one or more blocks of 10,000 shares each.

         (b) Automatic Conversion. Each share of Series B Preferred Stock shall
automatically be converted into shares of Common Stock at a ratio of one-to-one
on December 31, 2010.

         (c) Mechanics of Conversion. (i) Before any holder of Series B
Preferred Stock shall be entitled to convert into shares of Common Stock, he
shall surrender the certificate or certificates therefor, duly endorsed, at the
office of the Corporation or of any transfer agent for such stock, and shall
give written notice to the Corporation at such office that he elects to convert
the same and shall state names in which he wishes the certificate for shares of
Common Stock to be issued. The Corporation shall, as soon as practicable
thereafter, issue and deliver to such holder of Series B Preferred Stock, a
certificate for the number of shares of Common Stock to which he shall be
entitled. Such conversion shall be deemed to have been made immediately prior to
the close of business on the date of surrender of the shares of Series B
Preferred Stock to be converted, and the person entitled to receive the shares
of Common Stock issuable, upon such conversion shall be treated for all purposes
as the record holder of such shares of Common Stock on such date.

         (d) Reservation of Stock Issuable Upon Conversion. The Corporation
shall at all times reserve and keep available out of its authorized but unissued
shares Common Stock, solely for the

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purpose of effecting the conversion of the shares of the Series B Preferred
Stock, such number of its shares of Common Stock as shall from time to time be
sufficient to effect the conversion of all outstanding shares of the Series B
Preferred Stock; and if at any time the number of authorized but unissued shares
of Common Stock is not sufficient to effect the conversion of all then
outstanding shares of the Series B Preferred Stock, the Corporation will take
such corporate action as may, in the opinion of its counsel, be necessary to
increase its authorized but unissued shares of Common Stock to such number of
shares as shall be sufficient for such purpose, including, without limitation,
engaging in best efforts to obtain the requisite stockholder approval of any
necessary amendment to the Certificate of Incorporation.

         Shares of Series B Preferred Stock shall automatically convert into
shares of Common Stock at a ratio of one-to-one, on December 31, 2010. Promptly
after such date and surrender of the certificate or certificates for the share
or shares of Series B Preferred Stock to be converted, the Corporation shall
issue and deliver, or cause to be issued and delivered to each Holder a
certificate or certificates for the number of shares of Common Stock issuable
upon the conversion, subject to compliance with any agreement relating to
transfer by which such Holder is bound.

6.       VOTING RIGHTS.

         The holders of Series B Convertible Preferred Stock do not have voting
rights, except to the extent required by applicable law.

7.       MISCELLANEOUS.

         (a) Transfer of Preferred Shares. A Holder may sell or transfer all,
but not less than all, of the Holder's Series B Preferred Stock to any person or
entity as long as such sale or transfer is the subject of an effective
registration statement under the Securities Act or is exempt from registration
thereunder. From and after the date of such sale or transfer, the transferee
thereof shall be deemed to be a Holder. Upon any such sale or transfer, the
Corporation shall, promptly following the return of the certificate or
certificates representing the Series B Preferred Stock that is the subject of
such sale or transfer, issue and deliver to such transferee a new certificate in
the name of such transferee.

         (b) Notices. Except as otherwise provided herein, any notice, demand or
request required or permitted to be given pursuant to the terms hereof, the form
or delivery of which notice, demand or request is not otherwise specified
herein, shall be in writing and shall be deemed given (i) when delivered
personally or by verifiable facsimile transmission on or before 5:00 p.m.,
eastern time, on a Business Day or, if such day is not a Business Day, on the
next succeeding Business Day, (ii) on the next Business Day after timely
delivery to an overnight courier and (iii) on the third Business Day after
deposit in the U.S. mail (certified or registered mail, receipt requested,
postage prepaid), addressed to the parties as follows:


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                  If to the Corporation:

                           Zila, Inc.
                           5227 North 7th Street
                           Phoenix, Arizona 85014-2800
                           Attn:  Janice L. Backus, Vice President and Corporate
                                    Secretary
                           Tel: (602) 266-6700
                           Fax: (602) 234-2264

and if to any Holder, to such address for such Holder as shall be designated by
such Holder in writing to the Corporation.

         (c) Lost or Stolen Certificate. Upon receipt by the Corporation of
evidence of the loss, theft, destruction or mutilation of a certificate
representing any shares of Series B Preferred Stock, and (in the case of loss,
theft or destruction) of indemnity reasonably satisfactory to the Corporation,
and upon surrender and cancellation of such certificate if mutilated, the
Corporation shall execute and deliver to the Holder a new certificate identical
in all respects to the original certificate.


         IN WITNESS WHEREOF, the Corporation has caused this Certificate of
Designations to be signed by Joseph Hines, its President, as of the 1st day of
February, 2001.


                                      ZILA, INC.

                             By:      /s/ Joseph Hines
                             Name:    Joseph Hines
                             Its:     President


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