Exhibit 10.143

                                                                       EXHIBIT C

NEITHER THESE SECURITIES NOR THE SECURITIES ISSUABLE UPON EXERCISE OF THESE
SECURITIES HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR
THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM
REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT PURSUANT TO AN
EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN
AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION
REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH APPLICABLE STATE
SECURITIES LAWS AS EVIDENCED BY A LEGAL OPINION OF COUNSEL TO THE TRANSFEROR TO
SUCH EFFECT, THE SUBSTANCE OF WHICH SHALL BE REASONABLY ACCEPTABLE TO THE
COMPANY. THESE SECURITIES AND THE SECURITIES ISSUABLE UPON EXERCISE OF THESE
SECURITIES MAY BE PLEDGED IN CONNECTION WITH A BONA FIDE MARGIN ACCOUNT SECURED
BY SUCH SECURITIES.

                         CALYPTE BIOMEDICAL CORPORATION


                                     WARRANT


Warrant No. [  ]                              Original Issue Date: [     ], 2004

      Calypte Biomedical Corporation, a Delaware corporation (the "COMPANY"),
hereby certifies that, for value received, [ ] or its registered assigns (the
"HOLDER"), is entitled to purchase from the Company up to a total of [ ](1)
shares of Common Stock (each such share, a "WARRANT SHARE" and all such shares,
the "WARRANT SHARES"), at any time and from time to time from and after the
Original Issue Date and through and including [ ], 2009 (the "EXPIRATION DATE"),
and subject to the following terms and conditions:

      1. Definitions. As used in this Warrant, the following terms shall have
the respective definitions set forth in this Section 1. Capitalized terms that
are used and not defined in this Warrant that are defined in the Purchase
Agreement (as defined below) shall have the respective definitions set forth in
the Purchase Agreement.

      "BUSINESS DAY" means any day except Saturday, Sunday and any day that is a
federal legal holiday in the United States or a day on which banking
institutions in the State of New York are authorized or required by law or other
government action to close.

(1)   A number of shares as equals 35% of the Shares issuable to such Investor
      at Closing under the Purchase Agreement.


                                       1
<PAGE>

      "COMMON STOCK" means the common stock of the Company, par value $.03 per
share, and any securities into which such common stock may hereafter be
reclassified.

      "EXERCISE PRICE" means $0.50, subject to adjustment in accordance with
Section 9.

      "ORIGINAL ISSUE DATE" means the Original Issue Date first set forth on the
first page of this Warrant.

      "NEW YORK COURTS" means the state and federal courts sitting in the City
of New York, Borough of Manhattan.

      "PURCHASE AGREEMENT" means the Securities Purchase Agreement, dated May [
], 2004, to which the Company and the original Holders are parties.

      "TRADING DAY" means (i) a day on which the Common Stock is traded on a
Trading Market (other than the OTC Bulletin Board), or (ii) if the Common Stock
is not listed on a Trading Market (other than the OTC Bulletin Board), a day on
which the Common Stock is traded in the over-the-counter market, as reported by
the OTC Bulletin Board, or (iii) if the Common Stock is not quoted on any
Trading Market, a day on which the Common Stock is quoted in the
over-the-counter market as reported by the National Quotation Bureau
Incorporated (or any similar organization or agency succeeding to its functions
of reporting prices); provided, that in the event that the Common Stock is not
listed or quoted as set forth in (i), (ii) and (iii) hereof, then Trading Day
shall mean a Business Day.

      2. Registration of Warrant. The Company shall register this Warrant upon
records to be maintained by the Company for that purpose (the "WARRANT
REGISTER"), in the name of the record Holder hereof from time to time. The
Company may deem and treat the registered Holder of this Warrant as the absolute
owner hereof for the purpose of any exercise hereof or any distribution to the
Holder, and for all other purposes, absent actual notice to the contrary.

      3. Registration of Transfers. The Company shall register the transfer of
any portion of this Warrant in the Warrant Register, upon surrender of this
Warrant, with the Form of Assignment attached hereto duly completed and signed,
to the Company at its address specified herein. Upon any such registration or
transfer, a new Warrant to purchase Common Stock, in substantially the form of
this Warrant (any such new Warrant, a "NEW Warrant"), evidencing the portion of
this Warrant so transferred shall be issued to the transferee and a New Warrant
evidencing the remaining portion of this Warrant not so transferred, if any,
shall be issued to the transferring Holder. The acceptance of the New Warrant by
the transferee thereof shall be deemed the acceptance by such transferee of all
of the rights and obligations of a holder of a Warrant.

      4. Exercise and Duration of Warrants. This Warrant shall be exercisable by
the registered Holder at any time and from time to time on or after the Original
Issue Date through and including the Expiration Date. At 6:30 p.m., New York
City time on the Expiration Date, the portion of this Warrant not exercised
prior thereto shall be and become void and of no value. The Company may not call
or redeem any portion of this Warrant without the prior written consent of the
affected Holder.


                                       2
<PAGE>

      5. Delivery of Warrant Shares.

            (a) To effect exercises hereunder, the Holder shall not be required
to physically surrender this Warrant unless the aggregate Warrant Shares
represented by this Warrant is being exercised. Upon delivery of the Exercise
Notice (in the form attached hereto) to the Company (with the attached Warrant
Shares Exercise Log) at its address for notice set forth herein and upon payment
of the Exercise Price multiplied by the number of Warrant Shares that the Holder
intends to purchase hereunder, the Company shall promptly (but in no event later
than three Trading Days after the Date of Exercise (as defined herein)) issue
and deliver to the Holder, a certificate for the Warrant Shares issuable upon
such exercise, which, unless otherwise required by the Purchase Agreement, shall
be free of restrictive legends. The Company shall, upon request of the Holder
and subsequent to the date on which a registration statement covering the resale
of the Warrant Shares has been declared effective by the Securities and Exchange
Commission, use its reasonable best efforts to deliver Warrant Shares hereunder
electronically through the Depository Trust Corporation or another established
clearing corporation performing similar functions, if available, provided, that,
the Company may, but will not be required to change its transfer agent if its
current transfer agent cannot deliver Warrant Shares electronically through the
Depository Trust Corporation. A "DATE OF EXERCISE" means the date on which the
Holder shall have delivered to the Company: (i) the Exercise Notice (with the
Warrant Exercise Log attached to it), appropriately completed and duly signed
and (ii) if such Holder is not utilizing the cashless exercise provisions set
forth in this Warrant, payment of the Exercise Price for the number of Warrant
Shares so indicated by the Holder to be purchased.

            (b) If by the third Trading Day after a Date of Exercise the Company
fails to deliver the required number of Warrant Shares in the manner required
pursuant to Section 5(a), then the Holder will have the right to rescind such
exercise.

            (c) If by the third Trading Day after a Date of Exercise the Company
fails to deliver the required number of Warrant Shares in the manner required
pursuant to Section 5(a), and if after such third Trading Day and prior to the
receipt of such Warrant Shares, the Holder purchases (in an open market
transaction or otherwise) shares of Common Stock to deliver in satisfaction of a
sale by the Holder of the Warrant Shares which the Holder anticipated receiving
upon such exercise (a "BUY-IN"), then the Company shall (1) pay in cash to the
Holder the amount by which (x) the Holder's total purchase price (including
brokerage commissions, if any) for the shares of Common Stock so purchased
exceeds (y) the amount obtained by multiplying (A) the number of Warrant Shares
that the Company was required to deliver to the Holder in connection with the
exercise at issue by (B) the closing bid price of the Common Stock at the time
of the obligation giving rise to such purchase obligation and (2) at the option
of the Holder, either reinstate the portion of the Warrant and equivalent number
of Warrant Shares for which such exercise was not honored or deliver to the
Holder the number of shares of Common Stock that would have been issued had the
Company timely complied with its exercise and delivery obligations hereunder.
The Holder shall provide the Company written notice indicating the amounts
payable to the Holder in respect of the Buy-In.

            (d) The Company's obligations to issue and deliver Warrant Shares in
accordance with the terms hereof are absolute and unconditional, irrespective of
any action or inaction by the Holder to enforce the same, any waiver or consent
with respect to any provision hereof, the recovery of any judgment against any
Person or any action to enforce the same, or any setoff, counterclaim,
recoupment, limitation or termination, or any breach or alleged breach by the
Holder or any other Person of any obligation to the Company or any violation or
alleged violation of law by the Holder or any other Person, and irrespective of
any other circumstance which might otherwise limit such obligation of the
Company to the Holder in connection with the issuance of Warrant Shares. Nothing
herein shall limit a Holder's right to pursue any other remedies available to it
hereunder, at law or in equity including, without limitation, a decree of
specific performance and/or injunctive relief with respect to the Company's
failure to timely deliver certificates representing Warrant Shares upon exercise
of the Warrant as required pursuant to the terms hereof.


                                       3
<PAGE>

      6. Charges, Taxes and Expenses. Issuance and delivery of Warrant Shares
upon exercise of this Warrant shall be made without charge to the Holder for any
issue or transfer tax, withholding tax, transfer agent fee or other incidental
tax or expense in respect of the issuance of such certificates, all of which
taxes and expenses shall be paid by the Company; provided, however, that the
Company shall not be required to pay any tax which may be payable in respect of
any transfer involved in the registration of any certificates for Warrant Shares
or Warrants in a name other than that of the Holder. The Holder shall be
responsible for all other tax liability that may arise as a result of holding or
transferring this Warrant or receiving Warrant Shares upon exercise hereof.

      7. Replacement of Warrant. If this Warrant is mutilated, lost, stolen or
destroyed, the Company shall issue or cause to be issued in exchange and
substitution for and upon cancellation hereof, or in lieu of and substitution
for this Warrant, a New Warrant, but only upon receipt of evidence reasonably
satisfactory to the Company of such loss, theft or destruction and customary and
reasonable indemnity (which shall not include a surety bond), if requested.
Applicants for a New Warrant under such circumstances shall also comply with
such other reasonable regulations and procedures and pay such other reasonable
third-party costs as the Company may prescribe. If a New Warrant is requested as
a result of a mutilation of this Warrant, then the Holder shall deliver such
mutilated Warrant to the Company as a condition precedent to the Company's
obligation to issue the New Warrant.

      8. Reservation of Warrant Shares. The Company covenants that it will at
all times reserve and keep available out of the aggregate of its authorized but
unissued and otherwise unreserved Common Stock, solely for the purpose of
enabling it to issue Warrant Shares upon exercise of this Warrant as herein
provided, the number of Warrant Shares which are then issuable and deliverable
upon the exercise of this entire Warrant, free from preemptive rights or any
other contingent purchase rights of Persons other than the Holder (taking into
account the adjustments and restrictions of Section 9). The Company covenants
that all Warrant Shares so issuable and deliverable shall, upon issuance and the
payment of the applicable Exercise Price in accordance with the terms hereof, be
duly and validly authorized, issued and fully paid and nonassessable.

      9. Certain Adjustments. The Exercise Price and number of Warrant Shares
issuable upon exercise of this Warrant are subject to adjustment from time to
time as set forth in this Section 9.


                                       4
<PAGE>

            (a) Stock Dividends and Splits. If the Company, at any time while
this Warrant is outstanding, (i) pays a stock dividend on its Common Stock or
otherwise makes a distribution on any class of capital stock that is payable in
shares of Common Stock, (ii) subdivides outstanding shares of Common Stock into
a larger number of shares, or (iii) combines outstanding shares of Common Stock
into a smaller number of shares, then in each such case the Exercise Price shall
be multiplied by a fraction of which the numerator shall be the number of shares
of Common Stock outstanding immediately before such event and of which the
denominator shall be the number of shares of Common Stock outstanding
immediately after such event. Any adjustment made pursuant to clause (i) of this
paragraph shall become effective immediately after the record date for the
determination of stockholders entitled to receive such dividend or distribution,
and any adjustment pursuant to clause (ii) or (iii) of this paragraph shall
become effective immediately after the effective date of such subdivision or
combination.

            (b) Fundamental Transactions. If, at any time while this Warrant is
outstanding, (1) the Company effects any merger or consolidation of the Company
with or into another Person, (2) the Company effects any sale of all or
substantially all of its assets in one or a series of related transactions, (3)
any tender offer or exchange offer (whether by the Company or another Person) is
completed pursuant to which holders of Common Stock are permitted to tender or
exchange their shares for other securities, cash or property, or (4) the Company
effects any reclassification of the Common Stock or any compulsory share
exchange pursuant to which the Common Stock is effectively converted into or
exchanged for other securities, cash or property (in any such case, a
"FUNDAMENTAL TRANSACTION"), then the Holder shall have the right thereafter to
receive, upon exercise of this Warrant, the same amount and kind of securities,
cash or property as it would have been entitled to receive upon the occurrence
of such Fundamental Transaction if it had been, immediately prior to such
Fundamental Transaction, the holder of the number of Warrant Shares then
issuable upon exercise in full of this Warrant (the "ALTERNATE CONSIDERATION").
For purposes of any such exercise, the determination of the Exercise Price shall
be appropriately adjusted to apply to such Alternate Consideration based on the
amount of Alternate Consideration issuable in respect of one share of Common
Stock in such Fundamental Transaction, and the Company shall apportion the
Exercise Price among the Alternate Consideration in a reasonable manner
reflecting the relative value of any different components of the Alternate
Consideration. If holders of Common Stock are given any choice as to the
securities, cash or property to be received in a Fundamental Transaction, then
the Holder shall be given the same choice as to the Alternate Consideration it
receives upon any exercise of this Warrant following such Fundamental
Transaction. At the Holder's option and request, any successor to the Company or
surviving entity in such Fundamental Transaction shall, either (1) issue to the
Holder a new warrant substantially in the form of this Warrant and consistent
with the foregoing provisions and evidencing the Holder's right to purchase the
Alternate Consideration for the aggregate Exercise Price upon exercise thereof,
or (2) purchase the Warrant from the Holder for a purchase price, payable in
cash within five Trading Days after such request (or, if later, on the effective
date of the Fundamental Transaction), equal to the Black Scholes value of the
remaining unexercised portion of this Warrant on the date of such request. The
terms of any agreement pursuant to which a Fundamental Transaction is effected
shall include terms requiring any such successor or surviving entity to comply
with the provisions of this paragraph (c) and insuring that the Warrant (or any
such replacement security) will be similarly adjusted upon any subsequent
transaction analogous to a Fundamental Transaction.


                                       5
<PAGE>

            (c) Subsequent Equity Sales.

                  (i) If the Company or any subsidiary thereof, as applicable
with respect to Common Stock Equivalents, at any time while this Warrant is
outstanding, shall issue any securities of the Company or any Subsidiary which
entitle the holder thereof to acquire Common Stock at any time, including
without limitation, any debt, preferred stock, rights, options, warrants or any
other instrument that is at any time convertible into or exchangeable for, or
otherwise entitles the holder thereof to receive, Common Stock or Common Stock
Equivalents entitling any Person to acquire shares of Common Stock, at a price
per share less than $0.40 (appropriately adjusted for any stock splits, stock
combinations or similar events occurring prior to such time) (if the holder of
the Common Stock or Common Stock Equivalent so issued shall at any time, whether
by operation of purchase price adjustments, reset provisions, floating
conversion, exercise or exchange prices or otherwise, or due to warrants,
options or rights issued in connection with such issuance, be entitled to
receive shares of Common Stock at a price less than $0.40 (appropriately
adjusted for any stock splits, stock combinations or similar events occurring
prior to such time), such issuance shall be deemed to have occurred for less
than $0.40 (appropriately adjusted for any stock splits, stock combinations or
similar events occurring prior to such time)), then, at the option of the Holder
for such exercises as it shall indicate, the Exercise Price shall be multiplied
by a fraction, the numerator of which shall be the number of shares of Common
Stock outstanding immediately prior to the issuance of such shares of Common
Stock or such Common Stock Equivalents plus the number of shares of Common Stock
which the offering price for such shares of Common Stock or Common Stock
Equivalents would purchase at the Exercise Price, and the denominator of which
shall be the sum of the number of shares of Common Stock outstanding immediately
prior to such issuance plus the number of shares of Common Stock so issued or
issuable. Such adjustment shall be made whenever such Common Stock or Common
Stock Equivalents are issued. The Company shall notify the Holder in writing, no
later than the Trading Day following the issuance of any Common Stock or Common
Stock Equivalent subject to this section, indicating therein the applicable
issuance price, or of applicable reset price, exchange price, conversion price
and other pricing terms. Notwithstanding the foregoing, no adjustment will be
made under this Section 9(c) in respect of:

                        (1) any grant of an option or warrant for Common Stock
or issuance of any shares of Common Stock upon the exercise of any options or
warrants to employees, officers and directors of or consultants to the Company
pursuant to any stock option plan, employee stock purchase plan or similar plan
or incentive or consulting arrangement approved by the Company's board of
directors;

                        (2) any restricted stock awards approved by the
Company's Board of Directors;

                        (3) shares of Common Stock or Common Stock Equivalents
issued as consideration for the acquisition of another company or business in
which the shareholders of the Company do not have an ownership interest, which
acquisition has been approved by the Board of Directors of the Company;

                        (4) any rights or agreements to purchase Common Stock
Equivalents outstanding on the date hereof and as specified in Schedule 3.1(g)
to the Purchase Agreement (but not as to any amendments or other modifications
to the number of Common Stock issuable thereunder, the terms set forth therein,
or the exercise price set forth therein);


                                       6
<PAGE>

                        (5) issuance of shares of Common Stock to Logisticorp
and Southwest Resource Preservation, Inc., based upon the issuance and
conversion of outstanding convertible debentures, with the issuance of said
Common Stock not to exceed 700,000 shares; or

                        (6) up to an aggregate of 500,000 shares of Common Stock
(including any shares of Common Stock issuable in respect of Common Stock
Equivalents) issued or issuable as part of an equipment financing line in the
ordinary course of business or a modification to the existing MTVB facility,
approved by the Company's Board of Directors, in each case, at a price not less
than the market price of the Common Stock at the time of the issuance.

                  (ii) If, at any time while this Warrant is outstanding, the
Company or any Subsidiary issues Common Stock Equivalents at a price per share
that floats or resets or otherwise varies or is subject to adjustment based on
market prices of the Common Stock (a "FLOATING PRICE SECURITY"), then for
purposes of applying the preceding paragraph in connection with any subsequent
exercise, the Exercise Price will be determined separately on each Exercise Date
and will be deemed to equal the lowest price per share at which any holder of
such Floating Price Security is entitled to acquire shares of Common Stock on
such Exercise Date (regardless of whether any such holder actually acquires any
shares on such date).

            (d) Number of Warrant Shares. Simultaneously with any adjustment to
the Exercise Price pursuant to this Section 9, the number of Warrant Shares that
may be purchased upon exercise of this Warrant shall be increased or decreased
proportionately, so that after such adjustment the aggregate Exercise Price
payable hereunder for the adjusted number of Warrant Shares shall be the same as
the aggregate Exercise Price in effect immediately prior to such adjustment.

            (e) Calculations. All calculations under this Section 9 shall be
made to the nearest cent or the nearest 1/100th of a share, as applicable. The
number of shares of Common Stock outstanding at any given time shall not include
shares owned or held by or for the account of the Company, and the disposition
of any such shares shall be considered an issue or sale of Common Stock.

            (f) Notice of Adjustments. Upon the occurrence of each adjustment
pursuant to this Section 9, the Company at its expense will promptly compute
such adjustment in accordance with the terms of this Warrant and prepare a
certificate setting forth such adjustment, including a statement of the adjusted
Exercise Price and adjusted number or type of Warrant Shares or other securities
issuable upon exercise of this Warrant (as applicable), describing the
transactions giving rise to such adjustments and showing in detail the facts
upon which such adjustment is based. Upon written request, the Company will
promptly deliver a copy of each such certificate to the Holder and to the
Company's Transfer Agent.


                                       7
<PAGE>

            (g) Notice of Corporate Events. If the Company (i) declares a
dividend or any other distribution of cash, securities or other property in
respect of its Common Stock, including without limitation any granting of rights
or warrants to subscribe for or purchase any capital stock of the Company or any
Subsidiary, (ii) authorizes or approves, enters into any agreement contemplating
or solicits stockholder approval for any Fundamental Transaction or (iii)
authorizes the voluntary dissolution, liquidation or winding up of the affairs
of the Company, then the Company shall deliver to the Holder a notice describing
the material terms and conditions of such transaction (but only to the extent
such disclosure would not result in the dissemination of material, non-public
information to the Holder) at least 10 calendar days prior to the applicable
record or effective date on which a Person would need to hold Common Stock in
order to participate in or vote with respect to such transaction, and the
Company will take all steps reasonably necessary in order to insure that the
Holder is given the practical opportunity to exercise this Warrant prior to such
time so as to participate in or vote with respect to such transaction; provided,
however, that the failure to deliver such notice or any defect therein shall not
affect the validity of the corporate action required to be described in such
notice.

      10. Payment of Exercise Price. The Holder may pay the Exercise Price in
one of the following manners:

            (a) Cash Exercise. The Holder may deliver immediately available
funds; or

            (b) Cashless Exercise. If an Exercise Notice is delivered following
the earlier of the (i) Effectiveness Date or (ii) Effective Date, at a time when
a registration statement permitting the Holder to resell the Warrant Shares is
not then effective or the prospectus forming a part thereof is not then
available to the Holder for the resale of the Warrant Shares, then the Holder
may notify the Company in an Exercise Notice of its election to utilize cashless
exercise, in which event the Company shall issue to the Holder the number of
Warrant Shares determined as follows:

                      X = Y [(A-B)/A]

                      where:

                      X = the number of Warrant Shares to be issued to the
                          Holder.

                      Y = the number of Warrant Shares with
                      respect to which this Warrant is being
                      exercised.

                      A = the average of the closing prices for
                      the five Trading Days immediately prior to
                      (but not including) the Exercise Date.

                      B = the Exercise Price.

For purposes of Rule 144 promulgated under the Securities Act, it is intended,
understood and acknowledged that the Warrant Shares issued in a cashless
exercise transaction shall be deemed to have been acquired by the Holder, and
the holding period for the Warrant Shares shall be deemed to have commenced, on
the date this Warrant was originally issued.


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<PAGE>

      11. Limitations on Exercise.

            (a) Notwithstanding anything to the contrary contained herein, the
number of Warrant Shares that may be acquired by the Holder upon any exercise of
this Warrant (or otherwise in respect hereof) shall be limited to the extent
necessary to insure that, following such exercise (or other issuance), the total
number of shares of Common Stock then beneficially owned by such Holder and its
Affiliates and any other Persons whose beneficial ownership of Common Stock
would be aggregated with the Holder's for purposes of Section 13(d) of the
Exchange Act, does not exceed 4.999% of the total number of issued and
outstanding shares of Common Stock (including for such purpose the shares of
Common Stock issuable upon such exercise). For such purposes, beneficial
ownership shall be determined in accordance with Section 13(d) of the Exchange
Act and the rules and regulations promulgated thereunder. This provision shall
not restrict the number of shares of Common Stock which a Holder may receive or
beneficially own in order to determine the amount of securities or other
consideration that such Holder may receive in the event of a Fundamental
Transaction as contemplated in Section 9 of this Warrant. By written notice to
the Company, the Holder may waive the provisions of this Section 11(a), but any
such waiver will not be effective until the 61st day after delivery of such
notice, nor will any such waiver effect any other Holder.

            (b) Notwithstanding anything to the contrary contained herein, the
number of Warrant Shares that may be acquired by the Holder upon any exercise of
this Warrant (or otherwise in respect hereof) shall be limited to the extent
necessary to insure that, following such exercise (or other issuance), the total
number of shares of Common Stock then beneficially owned by such Holder and its
Affiliates and any other Persons whose beneficial ownership of Common Stock
would be aggregated with the Holder's for purposes of Section 13(d) of the
Exchange Act, does not exceed 9.999% of the total number of issued and
outstanding shares of Common Stock (including for such purpose the shares of
Common Stock issuable upon such exercise). For such purposes, beneficial
ownership shall be determined in accordance with Section 13(d) of the Exchange
Act and the rules and regulations promulgated thereunder. This provision shall
not restrict the number of shares of Common Stock which a Holder may receive or
beneficially own in order to determine the amount of securities or other
consideration that such Holder may receive in the event of a Fundamental
Transaction as contemplated in Section 9 of this Warrant. This restriction may
not be waived.

      12. No Fractional Shares. No fractional shares of Warrant Shares will be
issued in connection with any exercise of this Warrant. In lieu of any
fractional shares which would, otherwise be issuable, the Company shall pay cash
equal to the product of such fraction multiplied by the closing price of one
Warrant Share as reported by the applicable Trading Market on the date of
exercise.

      13. Notices. Any and all notices or other communications or deliveries
hereunder (including, without limitation, any Exercise Notice) shall be in
writing and shall be deemed given and effective on the earliest of (i) the date
of transmission, if such notice or communication is delivered via facsimile at
the facsimile number specified in this Section prior to 6:30 p.m. (New York City
time) on a Trading Day, (ii) the next Trading Day after the date of
transmission, if such notice or communication is delivered via facsimile at the
facsimile number specified in this Section on a day that is not a Trading Day or
later than 6:30 p.m. (New York City time) on any Trading Day, (iii) the Trading
Day following the date of mailing, if sent by nationally recognized overnight
courier service, or (iv) upon actual receipt by the party to whom such notice is
required to be given. The addresses for such communications shall be: (i) if to


                                       9
<PAGE>

the Company, to Calypte Biomedical Corporation, Attn: President, or to Facsimile
No.: (510) 814-8494 (or such other address as the Company shall indicate in
writing in accordance with this Section), or (ii) if to the Holder, to the
address or facsimile number appearing on the Warrant Register or such other
address or facsimile number as the Holder may provide to the Company in
accordance with this Section.

      14. Warrant Agent. The Company shall serve as warrant agent under this
Warrant. Upon 10 days' notice to the Holder, the Company may appoint a new
warrant agent. Any corporation into which the Company or any new warrant agent
may be merged or any corporation resulting from any consolidation to which the
Company or any new warrant agent shall be a party or any corporation to which
the Company or any new warrant agent transfers substantially all of its
corporate trust or shareholders services business shall be a successor warrant
agent under this Warrant without any further act. Any such successor warrant
agent shall promptly cause notice of its succession as warrant agent to be
mailed (by first class mail, postage prepaid) to the Holder at the Holder's last
address as shown on the Warrant Register.

      15. Miscellaneous.

            (a) This Warrant shall be binding on and inure to the benefit of the
parties hereto and their respective successors and assigns. Subject to the
preceding sentence, nothing in this Warrant shall be construed to give to any
Person other than the Company and the Holder any legal or equitable right,
remedy or cause of action under this Warrant. This Warrant may be amended only
in writing signed by the Company and the Holder and their successors and
assigns.

            (b) All questions concerning the construction, validity, enforcement
and interpretation of this Warrant shall be governed by and construed and
enforced in accordance with the internal laws of the State of New York (except
for matters governed by corporate law in the State of Delaware), without regard
to the principles of conflicts of law thereof. Each party agrees that all legal
proceedings concerning the interpretations, enforcement and defense of this
Warrant and the transactions herein contemplated ("PROCEEDINGS") (whether
brought against a party hereto or its respective Affiliates, employees or
agents) shall be commenced exclusively in the New York Courts. Each party hereto
hereby irrevocably submits to the exclusive jurisdiction of the New York Courts
for the adjudication of any dispute hereunder or in connection herewith or with
any transaction contemplated hereby or discussed herein, and hereby irrevocably
waives, and agrees not to assert in any Proceeding, any claim that it is not
personally subject to the jurisdiction of any New York Court, or that such
Proceeding has been commenced in an improper or inconvenient forum. Each party
hereto hereby irrevocably waives personal service of process and consents to
process being served in any such Proceeding by mailing a copy thereof via
registered or certified mail or overnight delivery (with evidence of delivery)
to such party at the address in effect for notices to it under this Warrant and
agrees that such service shall constitute good and sufficient service of process
and notice thereof. Nothing contained herein shall be deemed to limit in any way
any right to serve process in any manner permitted by law. Each party hereto
hereby irrevocably waives, to the fullest extent permitted by applicable law,
any and all right to trial by jury in any legal proceeding arising out of or
relating to this Warrant or the transactions contemplated hereby. If either
party shall commence a Proceeding to enforce any provisions of this Warrant,
then the prevailing party in such Proceeding shall be reimbursed by the other
party for its attorney's fees and other costs and expenses incurred with the
investigation, preparation and prosecution of such Proceeding.


                                       10
<PAGE>

      t 12 (c) The headings herein are for convenience only, do not constitute a
part of this Warrant and shall not be deemed to limit or affect any of the
provisions hereof.

            (d) In case any one or more of the provisions of this Warrant shall
be invalid or unenforceable in any respect, the validity and enforceability of
the remaining terms and provisions of this Warrant shall not in any way be
affected or impaired thereby and the parties will attempt in good faith to agree
upon a valid and enforceable provision which shall be a commercially reasonable
substitute therefor, and upon so agreeing, shall incorporate such substitute
provision in this Warrant.

            (e) Prior to exercise of this Warrant, the Holder hereof shall not,
by reason of by being a Holder, be entitled to any rights of a stockholder with
respect to the Warrant Shares

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK,
                             SIGNATURE PAGE FOLLOWS]


                                       11
<PAGE>

      IN WITNESS WHEREOF, the Company has caused this Warrant to be duly
executed by its authorized officer as of the date first indicated above.


                                      CALYPTE BIOMEDICAL CORPORATION



                                      By:
                                         --------------------------------------
                                         Name:
                                         Title:


                                       12
<PAGE>


                                 EXERCISE NOTICE
                         calypte biomedical corporation
                             WARRANT DATED [ ], 2004


The undersigned Holder hereby irrevocably elects to purchase _____________
shares of Common Stock pursuant to the above referenced Warrant. Capitalized
terms used herein and not otherwise defined have the respective meanings set
forth in the Warrant.

(1) The undersigned Holder hereby exercises its right to purchase
_________________ Warrant Shares pursuant to the Warrant.

(2) The Holder intends that payment of the Exercise Price shall be made as
(check one):

                      ____ "Cash Exercise" under Section 10

                      ____ "Cashless Exercise" under Section 10

(3) If the holder has elected a Cash Exercise, the holder shall pay the sum of
$____________ to the Company in accordance with the terms of the Warrant.

(4) Pursuant to this Exercise Notice, the Company shall deliver to the holder
_______________ Warrant Shares in accordance with the terms of the Warrant.

(5) By its delivery of this Exercise Notice, the undersigned represents and
warrants to the Company that in giving effect to the exercise evidenced hereby
the Holder will not beneficially own in excess of the number of shares of Common
Stock (determined in accordance with Section 13(d) of the Securities Exchange
Act of 1934) permitted to be owned under Section 11 of this Warrant to which
this notice relates.



Dated:               ,                  Name of Holder:
       --------------  -------

                                        (Print)
                                               ---------------------------------

                                        By:
                                               ---------------------------------
                                        Name:
                                               ---------------------------------

                                        Title:
                                               ---------------------------------

                                        (Signature must conform in all respects
                                        to name of holder as specified on the
                                        face of the Warrant)


                                       13
<PAGE>

                           Warrant Shares Exercise Log


-----------------------------------------------------------------------------
         Number of Warrant         Number of            Number of Warrant
         Share Available           Warrant Shares       Shares Remaining to
Date     to be Exercised           Exercised            be Exercised
----     ----------------          --------------       ---------------------


                                       14
<PAGE>

                         CALYPTE BIOMEDICAL CORPORATION
                       WARRANT ORIGINALLY ISSUED [ ], 2004
                                 WARRANT NO. [ ]

                               FORM OF ASSIGNMENT


         [To be completed and signed only upon transfer of Warrant]

         FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers
unto ________________________________ the right represented by the
above-captioned Warrant to purchase ____________ shares of Common Stock to which
such Warrant relates and appoints ________________ attorney to transfer said
right on the books of the Company with full power of substitution in the
premises.

Dated:   _______________, ____


                                       ---------------------------------------
                                       (Signature  must  conform in all respects
                                       to name of holder as specified on the
                                       face of the Warrant)


                                       ---------------------------------------
                                       Address of Transferee



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

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


In the presence of:


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



                                       15