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                                                                    Exhibit 4(b)


NEITHER THIS WARRANT NOR THE WARRANT STOCK HAS BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933. THE CORPORATION WILL NOT TRANSFER THIS WARRANT OR THE
WARRANT STOCK UNLESS (i) THERE IS AN EFFECTIVE REGISTRATION COVERING SUCH
WARRANT OR SUCH WARRANT STOCK, AS THE CASE MAY BE, UNDER THE SECURITIES ACT OF
1933 AND APPLICABLE STATES SECURITIES LAWS, (ii) IT FIRST RECEIVES A LETTER FROM
AN ATTORNEY, ACCEPTABLE TO THE BOARD OF DIRECTORS OR ITS AGENTS, STATING THAT IN
THE OPINION OF THE ATTORNEY THE PROPOSED TRANSFER IS EXEMPT FROM REGISTRATION
UNDER THE SECURITIES ACT OF 1933 AND UNDER ALL APPLICABLE STATE SECURITIES LAWS,
OR (iii) THE TRANSFER IS MADE PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF
1933.


Series B Warrants
Warrant Certificate No. ___

                                  DEMEGEN, INC.
                            (a Colorado corporation)

                   Warrant for the Purchase of [NUMBER] Shares
                                 of Common Stock
                            par value $.001 per share


Void after the earlier of (i) 5:00 p.m. Pittsburgh, Pennsylvania Time, on March
31, 2005 or (ii) that date which is sixty days after a call of this Warrant is
made in accordance with the provisions of Section 10 of this Warrant.


FOR VALUE RECEIVED, Demegen, Inc. (the "Corporation"), a Colorado corporation,
hereby certifies that ____________________________________, or assigns
("Holder"), is entitled, subject to the provisions of this Warrant, to purchase
from the Corporation at any time, or from time to time during the period
commencing on the date hereof and expiring on the earlier of (i) 5:00 p.m.
Pittsburgh, Pennsylvania Time, on March 31, 2005 or (ii) that date which is
sixty days after a call of this Warrant is made in accordance with the
provisions of Section 10 of this Warrant.
(such earlier date the "Expiration Date"), up to ______________ (________) fully
paid and non-assessable shares of Common Stock at a price of $0.75 per share
("Exercise Price").

The term "Common Stock" means the common stock, par value $.001 per share, of
the Corporation as constituted on February 1, 2000 ("Base Date"), together with
any other equity securities that may be issued by the Corporation in respect
thereof or in substitution therefor. The number of shares of Common Stock to be
received upon the exercise of this Warrant may be


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adjusted from time to time as hereinafter set forth. The shares of Common Stock
deliverable or delivered upon such exercise, as adjusted from time to time, are
hereinafter referred to as "Warrant Stock."

Upon receipt by the Corporation of evidence reasonably satisfactory to it of the
loss, theft, destruction or mutilation of this Warrant certificate, and (in the
case of loss, theft or destruction) of satisfactory indemnification, and upon
surrender and cancellation of this Warrant certificate, if mutilated, the
Corporation shall execute and deliver a new Warrant certificate of like tenor
and date.

Section 1. Exercise of Warrant. Subject to the call provision set forth in
Section 10, this Warrant may be exercised, subject to the requirements set forth
below, in whole, or in part, at any time during the period commencing on the
date hereof and expiring at 5:00 p.m. Pittsburgh, Pennsylvania Time on the
Expiration Date set forth above, or, if such day is a day on which banking
institutions in Pittsburgh, Pennsylvania are authorized by law to close, then on
the next succeeding day that shall not be such a day, by presentation and
surrender of this Warrant certificate to the Corporation at its principal
office, or at the office of its stock transfer agent, if any, with the Warrant
Exercise Form attached hereto duly executed and accompanied by payment (either
in cash or by certified or official bank check, payable to the order of the
Corporation) of the aggregate Exercise Price for the number of shares specified
in such form and instruments of transfer, if appropriate, duly executed by the
Holder. If this Warrant should be exercised in part only, the Corporation shall,
upon surrender of this Warrant certificate for cancellation, execute and deliver
a new Warrant certificate evidencing the rights of the Holder thereof to
purchase the balance of the shares purchasable hereunder. Upon receipt by the
Corporation of this Warrant certificate, together with the Exercise Price, at
its office, or by the stock transfer agent of the Corporation at its office, if
any, in proper form for exercise as described above, together with an agreement
to comply with the restrictions on transfer and related covenants contained
herein and a representation as to investment intent and any other matter
required by counsel to the Corporation, signed by the Holder (and if other than
the original Holder accompanied by proof, satisfactory to counsel for the
Corporation, of the right of such person or persons to exercise the Warrant),
the Holder shall be deemed to be the holder of record of the shares of Common
Stock issuable upon such exercise, even if the stock transfer books of the
Corporation shall then be closed or certificates representing such shares of
Common Stock shall not have been delivered to the Holder. The Holder shall pay
any and all documentary stamp or similar issue or transfer taxes payable in
respect of the issue or delivery of shares of Common Stock on exercise of this
Warrant. The Corporation shall promptly thereafter issue certificate(s)
evidencing the Common Stock so purchased.

Section 2. Reservation of Shares. The Corporation shall at all times reserve for
issuance and delivery upon exercise of this Warrant all shares of Common Stock
or other shares of capital stock of the Corporation (and other securities) from
time to time receivable upon exercise of this Warrant. All such shares (and
other securities) shall be duly authorized and, when issued upon exercise, shall
be validly issued, fully paid and non-assessable.


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Section 3. No Fractional Shares. No fractional shares or script representing
fractional shares shall be issued upon the exercise of this Warrant, but the
Corporation shall pay the Holder an amount equal to the fair market value of
such fractional share of Common Stock in lieu of each fraction of a share
otherwise called for upon any exercise of this Warrant. For purposes of this
Warrant, the fair market value of a share of Common Stock shall equal the
closing sale price (or if not available the average of the closing bid and asked
prices) on the business day prior to exercise of this Warrant, or, if the Common
Stock is then not publicly traded, then the price determined in good faith by
the Board of Directors of the Corporation.

Section 4. Transfer.

4.1 Securities Laws. Neither this Warrant nor the Warrant Stock have been
registered under the Securities Act of 1933 ("Securities Act") or any state
securities laws. The Corporation will not transfer either this Warrant or the
Warrant Stock unless: (i) there is an effective registration covering such
Warrant or such Warrant Stock, as the case may be, under the Securities Act and
applicable states securities laws; (ii) it first receives a letter from an
attorney, acceptable to the Corporation's board of directors or its agents,
stating that in the opinion of such attorney the proposed transfer is exempt
from registration under the Securities Act and under all applicable state
securities laws; or (iii) the transfer is made pursuant to Rule 144 under the
Securities Act.

4.2 Conditions to Transfer. Prior to any such proposed transfer, and as a
condition thereto, if such transfer is not made pursuant to an effective
registration statement under the Securities Act, the Holder will, if requested
by the Corporation, deliver to the Corporation: (i) an investment covenant
signed by the proposed transferee; (ii) an agreement by such transferee that the
restrictive investment legend set forth above be placed on the certificate or
certificates representing the securities acquired by such transferee; (iii) an
agreement by such transferee that the Corporation may place a "stop transfer
order" with its transfer agent or registrar; and (iv) an agreement by the
transferee to indemnify the Corporation to the same extent as set forth in the
next succeeding Subsection.

4.3 Indemnity. The Holder acknowledges that the Holder understands the meaning
and legal consequences of this Subsection, and the Holder hereby agrees to
indemnify and hold harmless the Corporation, its representatives and each
officer and director thereof from and against any and all loss, damage or
liability (including all attorneys' fees and costs incurred in enforcing this
indemnity provision) due to or arising out of: (i) the inaccuracy of any
representation or the breach of any warranty of the Holder contained in, or any
other breach of, this Warrant; (ii) any transfer of any of this Warrant or the
Warrant Stock in violation of the Securities Act, the Securities Exchange Act of
1934, as amended ("Exchange Act"), or the rules and regulations promulgated
under either of such Acts; (iii) any transfer of this Warrant or any of the
Warrant Stock in a manner inconsistent with this Warrant; or (iv) any untrue
statement or omission to state any material fact in connection with the
investment representations or with respect to the facts and representations
supplied by the Holder to counsel to the Corporation upon which its opinion as
to a proposed transfer shall have been based.


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4.4 Holdback Period and Transfer. Except as specifically restricted hereby, this
Warrant and the Warrant Stock issued may be transferred by the Holder in whole
or in part at any time or from time to time. Upon surrender of this Warrant
certificate to the Corporation or at the office of its stock transfer agent, if
any, accompanied by a request for transfer of this Warrant to a transferee, and
accompanied by funds sufficient to pay any documentary stamp or similar issue or
transfer tax, and upon compliance with the provisions of this Section 4, the
Corporation shall, without charge, execute and deliver a new Warrant certificate
in the name of such transferee, and this Warrant certificate shall promptly be
canceled. Any assignment, transfer, pledge, hypothecation or other disposition
of this Warrant attempted contrary to the provisions of this Warrant, or any
levy of execution, attachment or other process attempted upon this Warrant,
shall be null and void and without effect.

Section 5. Rights of the Holder. The Holder shall not, by virtue hereof, be
entitled to any rights of a shareholder in the Corporation, either at law or
equity, unless and until this Warrant is exercised. The rights of the Holder are
limited to those expressed in this Warrant and are not enforceable against the
Corporation except to the extent set forth herein.

Section 6. Anti-Dilution Provisions.

6.1 Stock Splits, Dividends, Etc.

         6.1.1 If the Corporation shall at any time subdivide its outstanding
shares of Common Stock (or other securities at the time receivable upon the
exercise of the Warrant) by recapitalization, reclassification or split-up
thereof, or if the Corporation shall declare a stock dividend or distribute
shares of Common Stock to its stockholders, the number of shares of Common Stock
subject to this Warrant immediately prior to such subdivision shall be
proportionately increased, and if the Corporation shall at any time combine the
outstanding shares of Common Stock by recapitalization, reclassification or
combination thereof, the number of shares of Common Stock subject to this
Warrant immediately prior to such combination shall be proportionately
decreased. Any such adjustment and adjustment to the Exercise Price pursuant to
this Section shall be effective at the close of business on the effective date
of such subdivision or combination or if any adjustment is the result of a stock
dividend or distribution then the effective date for such adjustment based
thereon shall be the record date therefor.

         6.1.2 Whenever the number of shares of Common Stock purchasable upon
the exercise of this Warrant is adjusted, as provided in this Section, the
Exercise Price shall be adjusted to the nearest cent by multiplying such
Exercise Price immediately prior to such adjustment by a fraction (x) the
numerator of which shall be the number of shares of Common Stock purchasable
upon the exercise immediately prior to such adjustment, and (y) the denominator
of which shall be the number of shares of Common Stock so purchasable
immediately thereafter.


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6.2 Adjustment for Reorganization, Consolidation, Merger, Etc. In case of any
reorganization of the Corporation (or any other corporation, the securities of
which are at the time receivable on the exercise of this Warrant) after the Base
Date or in case after such date the Corporation (or any such other corporation)
shall consolidate with or merge into another corporation or convey all or
substantially all of its assets to another corporation, then, and in each such
case, the Holder of this Warrant upon the exercise as provided in Section 1 at
any time after the consummation of such reorganization, consolidation, merger or
conveyance, shall be entitled to receive, in lieu of the securities and property
receivable upon the exercise of this Warrant prior to such consummation, the
securities or property to which such Holder would have been entitled upon such
consummation if such Holder had exercised this Warrant immediately prior
thereto; in each such case, the terms of this Warrant shall be applicable to the
securities or property received upon the exercise of this Warrant after such
consummation.

6.3 Certificate as to Adjustments. In each case of an adjustment in the number
of shares of Common Stock receivable on the exercise of this Warrant, the
Corporation at its expense shall promptly compute such adjustment in accordance
with the terms of the Warrant and prepare a certificate executed by an officer
of the Corporation setting forth such adjustment and showing the facts upon
which such adjustment is based. The Corporation shall forthwith mail a copy of
each such certificate to each Holder.

6.4 Notices of Record Date, Etc. In case:

         6.4.1 the Corporation shall take a record of the holders of its Common
Stock (or other securities at the time receivable upon the exercise of the
Warrant) for the purpose of entitling them to receive any dividend (other than a
cash dividend at the same rate as the rate of the last cash dividend theretofore
paid) or other distribution, or any right to subscribe for, purchase or
otherwise acquire any shares of stock of any class or any other securities, or
to receive any other right; or

         6.4.2 of any voluntary or involuntary dissolution, liquidation or
winding-up of the Corporation, then, and in each such case, the Corporation
shall mail or cause to be mailed to each Holder a notice specifying, as the case
may be: (i) the date on which a record is to be taken for the purpose of such
dividend, distribution or right, and stating the amount and character of such
dividend, distribution or right; or (ii) the date on which such reorganization,
reclassification, consolidation, merger, conveyance, dissolution, liquidation or
winding-up is to take place, and the time, if any, to be fixed, as to which the
holders of record of Common Stock (or such other securities at the time
receivable upon the exercise of this Warrant) shall be entitled to exchange
their shares of Common Stock (or such other securities) for securities or other
property deliverable upon such reorganization, reclassification, consolidation,
merger, conveyance, dissolution, liquidation or winding-up. Such notice shall be
mailed at least twenty (20) days prior to the date therein specified, and this
Warrant may be exercised prior to said date during the term of the Warrant.


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Section 7. Legend and Stop Transfer Orders. Unless the shares of Warrant Stock
have been registered under the Securities Act, upon exercise of any of this
Warrant and the issuance of any of the shares of Warrant Stock, the Corporation
shall instruct its transfer agent, if any, to enter stop transfer orders with
respect to such shares, and all certificates representing shares of Warrant
Stock shall bear on the face thereof substantially the following legend:

         This certificate has not been registered under the Securities Act of
         1933. The Corporation will not transfer this certificate unless (i)
         there is an effective registration covering the shares represented by
         this certificate under the Securities Act of 1933 and all applicable
         state securities laws, (ii) it first receives a letter from an
         attorney, acceptable to the board of directors or its agents, stating
         that in the opinion of the attorney the proposed transfer is exempt
         from registration under the Securities Act of 1933 and under all
         applicable state securities laws, (iii) the transfer is made pursuant
         to Rule 144 under the Securities Act of 1933.

Section 8. Registration. The Corporation agrees that on or before March 31,
2001, it shall file a Registration Statement on Form SB-2, or any other
available form or successor form, under the Securities Act of 1933, as amended
(the "1933 Act") seeking registration of all shares of Warrant Stock and shall
use its commercially reasonable efforts to cause all such Warrant Shares to be
registered under the 1933 Act. Each Holder agrees to cooperate fully with the
Corporation in effecting registration and qualification of such Holder's Warrant
Shares, and shall indemnify and hold harmless the Corporation and each person
who may control the Corporation within the meaning of Section 15 of the 1933
Act, each director of the Corporation, and each officer who signed any
registration statement from and against any and all losses, claims, damages,
expenses, and liabilities caused by any untrue statement of fact or omission of
a material fact to the extent that such untrue statement or omission was made in
reliance upon information furnished to the Corporation by any such holder.

Section 9. Officer's Certificate. Whenever the number or kind of securities
purchasable upon exercise of this Warrant or the Exercise Price shall be
adjusted as required by the provisions hereof, the Corporation shall forthwith
file with its Secretary or Assistant Secretary at its principal office and with
its stock transfer agent, if any, an officer's certificate showing the adjusted
number of kind of securities purchasable upon exercise of this Warrant and the
adjusted Exercise Price determined as herein provided and setting forth in
reasonable detail such facts as shall be necessary to show the reason for and
the manner of computing such adjustments. Each such officer's certificate shall
be made available at all reasonable times for inspection by the Holder and the
Corporation shall, forthwith after each such adjustment, mail by certified mail
a copy of such certificate to the Holder.


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Section 10. Call Provisions.

10.1 Call of Warrants. At any time after March 31, 2001, the Corporation may
deliver to the Holder a Call Notice (as defined in section 10.3) provided that
the closing price of Corporation's Common Stock is $1.50 or more per share (as
adjusted for any stock splits or stock combination) for each of the forty (40)
consecutive trading days preceding the date of the Call Notice.

10.2 Exercise Following a Call Notice. Upon receipt of a Call Notice, the Holder
shall have a period of sixty (60) calendar days after the date of the Call
Notice to elect to exercise all or a portion of this Warrant in accordance with
the terms of Section 1. Following a Call Notice, any purchase rights under this
Warrant not exercised in accordance with this Section shall expire and this
Warrant shall be terminated.

10.3 Call Notices. A Call Notice shall be delivered by the Corporation in
writing to the Holder and shall specify that it is being submitted pursuant to
this Section 10 and shall include evidence of the closing price of the
Corporation's common stock for each of the forty (40) consecutive trading days
preceding the date of the Call Notice

Section 11. Law Governing. This Agreement shall be governed by and construed in
accordance with the laws of the Commonwealth of Pennsylvania.


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                              WARRANT EXERCISE FORM

The undersigned hereby irrevocably elects to exercise the within Warrant to the
extent of purchasing ______________ shares of Common Stock of Demegen, Inc. and
hereby makes payment of $_________________ in payment therefor.

Date:


__________________________
Signature


__________________________
Signature
(if jointly held)



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