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                                                                    Exhibit 4(a)


                             SUBSCRIPTION AGREEMENT

                            THE SHARES REFERRED TO IN
                     THIS AGREEMENT HAVE NOT BEEN REGISTERED
                     UNDER THE SECURITIES ACT OF 1933 OR ANY
                   APPLICABLE STATE SECURITIES LAWS, AND THEIR
                   TRANSFER IS RESTRICTED BY THE TERMS OF THIS
                        AGREEMENT AND BY APPLICABLE LAW.

                             SUBSCRIPTION AGREEMENT

TO:    Demegen, Inc.
       1051 Brinton Road
       Pittsburgh, PA 15221

Gentlemen:

1.       Description of Units; Subscription for Units.

         a)       Description of Units. Demegen, Inc., a Colorado corporation
                  (the "Company"), is offering to sell units of its securities,
                  such units to be comprised of (i) shares of its common stock,
                  $.001 par value ("Common Stock"), and (ii) warrants to
                  purchase Common Stock (the "Units"). Each Unit shall consist
                  of one (1) share of Common Stock and a warrant entitling the
                  holder to purchase one (1) share of Common Stock at any time
                  on or before March 31, 2005 at an exercise price of $0.75 per
                  share (the "Warrants"). The Warrants shall be in the form of
                  Exhibit A to this Subscription Agreement. The purchase price
                  of each Unit will be $0.50. The minimum purchase by each
                  subscriber is 20,000 Units for $10,000 unless the Company, in
                  its sole discretion, agrees otherwise.

         b)       Subscription for Units. The undersigned (the "Subscriber")
                  hereby subscribes for and agrees to purchase the number of
                  Units set forth on the Signature Page attached to this
                  Subscription Agreement. The Subscriber is delivering with this
                  Subscription Agreement a check in the amount of $_________
                  ($0.50 multiplied by the number of Units the Subscriber is
                  subscribing for) payable to the order of Demegen, Inc.

2.       Representations of the Subscriber. By executing this Subscription
         Agreement, the Subscriber hereby represents and warrants to the Company
         that:

         (i)      Subscriber understands that Subscriber must bear the economic
                  risk of an investment in the Units for an indefinite period of
                  time.

         (ii)     Subscriber understands that an investment in Company involves
                  certain risks and has taken full cognizance of and understands
                  all of the risk factors relating to the purchase of Shares as
                  set forth in the investment materials packet dated February
                  10, 2000 which were delivered to the Subscriber (the
                  "Investment Materials"), including the document entitled "List
                  of Recent Developments and Risk Factors" included the
                  Investment Materials.

         (iii)    Subscriber acknowledges that Subscriber has read and carefully
                  reviewed the Investment Materials and has based a decision to
                  invest solely on the information contained in the Investment
                  Materials; acknowledges that the Company has made available to
                  Subscriber the opportunity to ask questions of, and receive
                  answers from, the Company concerning the terms and conditions
                  of the offering and to obtain any additional information
                  necessary to verify the accuracy of the information given to
                  Subscriber in the Investment.

         (iv)     Subscriber is acquiring the Units for Subscriber's own account
                  as principal for investment and not with a view to resale or
                  distribution. Subscriber will not sell or otherwise transfer
                  the Shares except in accordance with applicable securities
                  laws.

         (v)      Subscriber is at least 21 years of age, and (a) Subscriber has
                  adequate means of providing for Subscriber's current needs and
                  personal contingencies, (b) Subscriber has no need for
                  liquidity in the investment in the Units, (c) Subscriber
                  maintains a principal domicile (and is not a transient or
                  temporary resident) at the



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                  address shown below, (d) all of Subscriber's investments in
                  and commitments to non-liquid investments are, and after
                  Subscriber's purchase of the Units will be, reasonable in
                  relation to Subscriber's net worth and current needs, and (e)
                  the personal financial information provided by Subscriber to
                  the Company in the "Accredited Purchaser Questionnaire"
                  contained in the Investor Materials accurately reflects
                  Subscriber's current financial condition, with respect to
                  which Subscriber does not anticipate any material adverse
                  changes.

         (vi)     Subscriber understands that the Company shall have the right,
                  in its sole discretion, to accept or reject this subscription,
                  in whole or in part, or to allocate to Subscriber only a
                  portion of the number of Units covered by this subscription.
                  The Company will notify Subscriber whether this subscription
                  is accepted or rejected. To the extent that Subscriber's
                  subscription is rejected, any payment made will be returned to
                  Subscriber without interest and all of Subscriber's
                  obligations hereunder with respect to the rejected portion of
                  the subscription shall terminate.

         (vii)    Subscriber understands that the neither the shares of Common
                  Stock nor the Warrants comprising the Units have been
                  registered under the Securities Act of 1933, as amended (the
                  "1933 Act"), or the securities laws of any state and, as the
                  result thereof, are subject to substantial restrictions on
                  transfer.

         (viii)   Subscriber understands and agrees that Subscriber will not
                  sell or otherwise transfer any shares of Common Stock or any
                  of the Warrants comprising the Units unless the Subscriber
                  provides the Company with an opinion of counsel which is
                  reasonably satisfactory to the Company (both as to the issuer
                  of the opinion and the form and substance thereof) that an
                  applicable exemption from the registration requirements of the
                  Securities Act, and any other applicable securities laws is
                  available for the proposed transfer.

         (ix)     Subscriber understands that (a) the Company has no obligation
                  or intention to register any of the shares of Common Stock or
                  any of the Warrants comprising the Units for resale under any
                  federal or state securities laws or to take any action (except
                  to the extent set forth in this Subscription Agreement and
                  except for the filing of reports or the publication of
                  information required by Rule 144 under the Securities Act),
                  which would make available any exemption from the registration
                  requirements of such laws, and (b) Subscriber therefore may be
                  precluded from selling or otherwise transferring or disposing
                  of any shares of Common Stock or any of the Warrants
                  comprising the Units, or any portion thereof, and may
                  therefore have to bear the economic risk of investment in the
                  Shares for an indefinite period of time.

         (x)      Subscriber understands that no federal or state agency has
                  approved or disapproved the Units, passed upon or endorsed the
                  merits of the offering thereof, or made any finding or
                  determination as to the fairness of the Units for investment.

         (xi)     Subscriber acknowledges that, if purchasing the Units
                  subscribed for hereby in a fiduciary capacity, the above
                  representations and warranties in this Section shall be deemed
                  to have been made on behalf of the person or persons for whom
                  the undersigned is so purchasing.

         (xii)    IF SUBSCRIBER IS A PENNSYLVANIA RESIDENT, THE SUBSCRIBER
                  ACKNOWLEDGES AND UNDERSTANDS THAT SUBSCRIBER HAS THE RIGHT TO
                  CANCEL AND WITHDRAW THIS SUBSCRIPTION AGREEMENT AND HIS OR HER
                  PURCHASE OF SHARES UPON WRITTEN NOTICE TO THE COMPANY GIVEN TO
                  THE COMPANY AT THE ADDRESS SET FORTH ABOVE WITHIN TWO BUSINESS
                  DAYS FOLLOWING RECEIPT BY THE COMPANY OF AN EXECUTED
                  SUBSCRIPTION AGREEMENT FOR THE UNITS. UPON SUCH CANCELLATION
                  OR WITHDRAWAL, THE SUBSCRIBER WILL HAVE NO OBLIGATION OR DUTY
                  UNDER THIS SUBSCRIPTION AGREEMENT TO THE COMPANY OR TO ANY
                  OTHER PERSON AND WILL BE ENTITLED TO THE FULL RETURN WITHOUT
                  INTEREST OF ANY AMOUNT PAID BY THE SUBSCRIBER PURSUANT TO THIS
                  SUBSCRIPTION AGREEMENT. SUBSCRIBER FURTHER ACKNOWLEDGES AND
                  UNDERSTANDS THAT ANY NOTICE OF CANCELLATION OR WITHDRAWAL
                  SHOULD BE MADE BY CERTIFIED OR REGISTERED MAIL OR TELEGRAPH OR
                  OTHER MESSAGE DELIVERY SERVICE. SUCH NOTICE WILL BE EFFECTIVE
                  UPON DEPOSIT IN THE UNITED STATES MAILS, SENT REGISTERED OR
                  CERTIFIED MAIL, OR DELIVERED TO A TELEGRAPH OR OTHER MESSAGE
                  SERVICE FOR TRANSMITTAL, WITH POSTAGE OR OTHER TRANSMITTAL
                  FEES PAID BY SUBSCRIBER.

         (xiii)   If Subscriber is a Pennsylvania resident, Subscriber agrees
                  that Subscriber will not sell any portion of the



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                  securities comprising Subscriber's Units purchased pursuant
                  thereto for one year following the purchase of the Units.

         (xiv)    Subscriber understands that the Units are being offered and
                  sold in reliance on specific exemptions from the registration
                  requirements of federal and state securities laws and that the
                  Company is relying upon the truth and accuracy of the
                  representations, warranties agreements, acknowledgments and
                  understandings set forth herein in order to determine the
                  applicability of such exemptions and the suitability of
                  Subscriber to acquire Shares.


3.       Registration Rights. The Company 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 1933 Act seeking
         registration of all shares of Common Stock (i) which comprise the Units
         and (ii) issuable upon exercise of the Warrants (collectively, the
         "Registerable Shares"), and shall use its commercially reasonable
         efforts to cause all such Registerable Shares to be registered under
         the 1933 Act. Each holder of any Registerable Shares agrees to
         cooperate fully with the Company in effecting registration and
         qualification of such holder's Registerable Shares, and shall indemnify
         and hold harmless the Company and each person who may control the
         Company within the meaning of Section 15 of the 1933 Act, each director
         of the Company, 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 Company by any such
         holder.

4.       Miscellaneous.

         a) Controlling Law. All questions relating to the interpretation,
construction and enforcement of this Agreement will be determined in accordance
with the domestic laws of the Commonwealth of Pennsylvania.

         b) Binding Nature of Agreement; No Assignment. This Agreement shall be
binding upon and inure to the benefit of the parties hereto and their respective
heirs, personal representatives, successors and assigns , except that the
Subscriber may not assign or transfer Subscriber's rights or obligations under
or interest in this Agreement without the prior written consent of the Company.

         c) Execution in Counterparts. This Agreement may be executed in any
number of counterparts, each of which shall be deemed to be an original as
against any party whose signature appears thereon, and all of which shall
together constitute one and the same instrument. If executed in multiple
counterparts, this Agreement shall become binding when two or more counterparts
hereto, individually or taken together, bear the signatures of all of the
parties reflected hereon as the signatories.

         d) Entire Agreement. This Agreement contains the entire understanding
among the parties hereto with respect to the subject matter hereof, and
supersedes all prior and contemporaneous agreements and understandings,
inducements or conditions, express or implied, oral or written.

         e) Disclaimer of Representations. Except as expressly set forth in the
Investor Materials, Company has not made any representations or warranties to
Subscriber and Subscriber expressly acknowledges that it is not relying on any
other information received from the Company or its representations (including,
without limitation, any projections, forecasts or forward-looking information.




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                                  DEMEGEN, INC.
                COUNTERPART SUBSCRIPTION AGREEMENT SIGNATURE PAGE

         Subscriber, desiring to purchase Units offered by the Company, by
executing this Signature Page hereby accepts, adopts and agrees to all terms,
conditions and representations of the foregoing Subscription Agreement and
agrees to subscribe for the number of Units stated below.

Number of  Units  subscribed for (20,000 Unit minimum):     _____ Units

Enclosed is a check payable to Demegen, Inc. for $___________ ($0.50 per Unit,
$10,000 minimum)

Date: February ____ , 2000

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<CAPTION>
<S>                                    <C>                                <C>
INDIVIDUALS SIGN BELOW:

-------------------------------         -------------------------------    -------------------------------
Subscriber's Signature                  Print Subscriber's Name            Social Security No.

-------------------------------         -------------------------------    -------------------------------
Joint Subscriber's Signature*           Print Joint Subscriber's Name      Social Security No.

* If Shares are to be owned jointly, both Subscribers must sign.


PARTNERSHIPS, TRUSTS AND OTHER ENTITIES SIGN BELOW:

Name of Entity:
               -------------------------------------------------------------------------------------------

By:
   ----------------------------------------------         ------------------------------------------------
                                                          Taxpayer Identification Number

Title:
      -------------------------------------------         ------------------------------------------------
                                                          Date

ALL SUBSCRIBERS COMPLETE THE ADDRESS SECTION

Principal Residence Address:                              Mailing Address, if different from
                                                          Residence Address:

   ----------------------------------------------         ------------------------------------------------

   ----------------------------------------------         ------------------------------------------------



                                          * * * * * * * * *



The foregoing Subscription is                             DEMEGEN, INC..
accepted on February  _____, 2000
to the extent of _____ Units                              By
                                                              ----------------------------------------------
                                                             Richard D. Ekstrom, President
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