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                                                                EXHIBIT 4.5

THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR
ANY APPLICABLE STATE SECURITIES LAWS.  THEY MAY NOT BE SOLD, OFFERED FOR SALE,
PLEDGED OR HYPOTHECATED OR OTHERWISE TRANSFERRED IN THE ABSENCE OF A
REGISTRATION STATEMENT IN EFFECT WITH RESPECT TO THE SECURITIES UNDER SUCH ACT
OR UNLESS SOLD PURSUANT TO RULE 144 OF SUCH ACT.  ANY SUCH TRANSFER MAY ALSO BE
SUBJECT TO APPLICABLE STATE SECURITIES LAWS.

                                XENOMETRIX, INC.


                 FORM OF WARRANT FOR THE PURCHASE OF SHARES OF 
                                  COMMON STOCK

NO. ____                                                          ______ SHARES


                 FOR VALUE RECEIVED, XENOMETRIX, INC., a Delaware corporation
(the "COMPANY"), hereby certifies that ______________________________________,
or its permitted assigns, is entitled to purchase from the Company, at any time
or from time to time commencing on SEPTEMBER 25, 1997, and prior to 5:00 P.M.,
New York City time, on SEPTEMBER 25, 2007 (the "TERMINATION DATE"), ______
fully paid and non-assessable shares of the Common Stock, $.001 par value per
share, of the Company (the "Common Stock") at an exercise price equal to the
lesser of (a) $2.14816 and (b) the price per share in the next placement of
equity securities of the Company where gross proceeds exceed three million
dollars ($3,000,000) (the "Private Placement").  (Hereinafter, (i) said Common
Stock, together with any other equity securities which may be issued by the
Company with respect thereto or in substitution therefor, is referred to as the
"COMMON STOCK", (ii) the shares of the Common Stock purchasable hereunder or
under any other Warrant (as hereinafter defined) are referred to as the
"WARRANT SHARES", (iii) the aggregate purchase price payable for the Warrant
Shares hereunder is referred to as the "AGGREGATE WARRANT PRICE", (iv) the
price payable for each of the Warrant Shares hereunder is referred to as the
"PER SHARE WARRANT PRICE", (v) this Warrant, all similar Warrants issued on the
date hereof and all warrants hereafter issued in exchange or substitution for
this Warrant or such similar Warrants are referred to as the "WARRANTS" and
(vi) the holder of this Warrant is referred to as the "HOLDER" and the holder
of this Warrant and all other Warrants or Warrant Shares issued upon the
exercise of any Warrant are referred to as the "HOLDERS").  The Aggregate
Warrant Price is not subject to adjustment.  The Per Share Warrant Price is
subject to adjustment as hereinafter provided; in the event of any such
adjustment, the number of Warrant Shares shall be adjusted by dividing the
Aggregate Warrant Price by the Per Share Warrant Price in effect immediately
after such adjustment.

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1.       EXERCISE OF WARRANT.

                 (a)      This Warrant may be exercised by the Holder, in whole
at any time or in part from time to time, commencing on September 25, 1997 and
prior to the Termination Date:

                 (i)      by the surrender of this Warrant (with the
         subscription form at the end hereof duly executed) at the address set
         forth in Subsection 10(a) hereof, together with proper payment of the
         Aggregate Warrant Price, or the proportionate part thereof if this
         Warrant is exercised in part, with payment for Warrant Shares made by
         certified or official bank check payable to the order of the Company;
         or

                 (ii)     by the surrender of this Warrant (with the cashless
         exercise form at the end hereof duly executed) (a "CASHLESS EXERCISE")
         at the address set forth in Subsection 10(a) hereof.  Such
         presentation and surrender shall be deemed a waiver of the Holder's
         obligation to pay the Aggregate Warrant Price, or the proportionate
         part thereof if this Warrant is exercised in part.  In the event of a
         Cashless Exercise, the Holder shall exchange its Warrant for that
         number of Warrant Shares subject to such Cashless Exercise multiplied
         by a fraction, the numerator of which shall be the difference between
         the then current Market Price per share (as hereinafter defined) of
         Common Stock and the Per Share Warrant Price, and the denominator of
         which shall be the then current Market Price per share of Common
         Stock.  The then current market price per share of the Common Stock at
         any date (the "MARKET PRICE") shall be deemed to be the last sale
         price of the Common Stock on the business day prior to the date of the
         Cashless Exercise or, in case no such reported sales take place on
         such day, the average of the last reported bid and asked prices of the
         Common Stock on such day, in either case on the principal national
         securities exchange on which the Common Stock is admitted to trading
         or listed, or if not listed or admitted to trading on any such
         exchange, the representative closing bid price of the Common Stock as
         reported by the NASDAQ Bulletin Board ("NASDAQ"), or other similar
         organization if NASDAQ is no longer reporting such information, or if
         not so available, the fair market price of the Common Stock as
         determined in good faith by the Board of Directors.

                 (b)      If this Warrant is exercised in part, this Warrant
must be exercised for a number of whole shares of the Common Stock and the
Holder is entitled to receive a new Warrant covering the Warrant Shares which
have not been exercised and setting forth the proportionate part of the
Aggregate Warrant Price applicable to such Warrant Shares.  Upon surrender of
this Warrant, the Company will (i) issue a certificate or certificates in the
name of the Holder for the largest number of whole shares of the Common Stock
to which the Holder shall be entitled and, if this Warrant is exercised in
whole, in lieu of any fractional share of the Common Stock to which the Holder
shall be entitled, pay to the Holder cash in an amount equal to the fair value
of such fractional share (determined in such reasonable





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manner as the Board of Directors of the Company shall determine), and (ii)
deliver the other securities and properties receivable upon the exercise of
this Warrant, if any, or the proportionate part thereof if this Warrant is
exercised in part, pursuant to the provisions of this Warrant.

                 2.       RESERVATION OF WARRANT SHARES; LISTING.  The Company
agrees that, prior to the expiration of this Warrant, the Company will at all
times (a) have authorized and in reserve, and will keep available, solely for
issuance or delivery upon the exercise of this Warrant, the shares of the
Common Stock and other securities and properties as from time to time shall be
receivable upon the exercise of this Warrant, free and clear of all
restrictions on sale or transfer, except for the restrictions on sale or
transfer set forth in the Securities Act of 1933, as amended (the "Act"), and
restrictions created by or on behalf of the Holder, and free and clear of all
preemptive rights and rights of first refusal and (b) when the Company prepares
and files a registration statement covering the shares of Common Stock issued
or issuable upon exercise of this Warrant with the Securities and Exchange
Commission (the "SEC") which registration statement is declared effective by
the SEC under the Act and the Company lists its Common Stock on any national
securities exchange or other quotation system, it will use its reasonable best
efforts to cause the shares of Common Stock subject to this Warrant to be
listed on such exchange or quotation system.

                 3.       PROTECTION AGAINST DILUTION.

                 (a)      If, at any time or from time to time after the date
of issuance of this Warrant, the Company shall issue or distribute to the
holders of shares of Common Stock evidence of its indebtedness, any other
securities of the Company or any cash, property or other assets (excluding a
subdivision, combination or reclassification, or dividend or distribution
payable in shares of Common Stock, referred to in Subsection 3(b), and also
excluding cash dividends or cash distributions paid out of net profits legally
available therefor in the full amount thereof, which together with the value of
other dividends and distributions made substantially concurrently therewith or
pursuant to a plan which includes payment thereof, is equivalent to not more
than 5% of the Company's net worth) (any such non-excluded event being herein
called a "SPECIAL DIVIDEND"), the Per Share Warrant Price shall be adjusted by
multiplying the Per Share Warrant Price then in effect by a fraction, the
numerator of which shall be the then current Market Price of the Common Stock
less the fair market value (as determined in good faith by the Company's Board
of Directors) of the evidence of indebtedness, cash, securities or property, or
other assets issued or distributed in such Special Dividend applicable to one
share of Common Stock and the denominator of which shall be the then current
Market Price of the Common Stock.  An adjustment made pursuant to this
Subsection 3(a) shall become effective immediately after the record date of any
such Special Dividend.
                 
                 (b)      In case the Company shall hereafter (i) pay a
dividend or make a distribution on its capital stock in shares of Common Stock,
(ii) subdivide its outstanding shares of Common Stock into a greater number of
shares, (iii) combine its outstanding shares of Common Stock into a smaller
number of shares or (iv) issue by reclassification of its





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Common Stock any shares of capital stock of the Company, the Per Share Warrant
Price shall be adjusted to be equal to a fraction, the numerator of which shall
be the Aggregate Warrant Price and the denominator of which shall be the number
of shares of Common Stock or other capital stock of the Company which the
Holder would have owned immediately following such action had such Warrant been
exercised immediately prior thereto.  An adjustment made pursuant to this
Subsection 3(b) shall become effective immediately after the record date in the
case of a dividend or distribution and shall become effective immediately after
the effective date in the case of a subdivision, combination or
reclassification.

                 (c)      Except as provided in subsections 3(a) and 3(d), in
case the Company shall hereafter issue or sell any Common Stock, any securities
convertible into Common Stock or any rights, options or warrants to purchase
Common Stock or securities convertible into Common Stock, in each case for a
price per share or entitling the holders thereof to purchase Common Stock at a
price per share (determined by dividing (i) the total amount, if any, received
or receivable by the Company in consideration of the issuance or sale of such
securities plus the total consideration, if any, payable to the Company upon
exercise or conversion thereof (the "TOTAL CONSIDERATION") by (ii) the number
of additional shares of Common Stock issued, sold or issuable upon exercise or
conversion of such securities) less than the then current Market Price of the
Common Stock or the current Per Share Warrant Price in effect on the date of
such issuance or sale, the Per Share Warrant Price shall be adjusted by
multiplying the Per Share Warrant Price then in effect by a fraction, the
numerator of which shall be (x) the sum of (A) the number of shares of Common
Stock outstanding on the record date of such issuance or sale plus (B) the
Total Consideration divided by either the current Market Price of the Common
Stock or the current Per Share Warrant Price, whichever is greater, and the
denominator of which shall be (y) the number of shares of Common Stock
outstanding on the record date of such issuance or sale plus the maximum number
of additional shares of Common Stock issued, sold or issuable upon exercise or
conversion of such securities.

                 (d)      Except as otherwise provided herein, no adjustment in
the Per Share Warrant Price shall be required in the case of the issuance by
the Company of (i) Common Stock pursuant to the exercise or conversion of any
Warrant or any other options, warrants or any convertible securities currently
outstanding or outstanding as a result of securities hereafter issued;
provided, that the exercise price or conversion price at which such securities
are exercised or converted, as the case may be, is equal to the exercise price
or conversion price in effect as of the date of this Warrant or as of the date
of issuance with respect to securities hereafter issued (except for standard
anti- dilution adjustments) and (ii) shares of Common Stock issued or sold
pursuant to stock purchase or stock option plans or other similar arrangements
that are approved by the Company's Board of Directors.

                 (e)      In case of any capital reorganization or
reclassification, or any consolidation or merger to which the Company is a
party other than a merger or consolidation in which the Company is the
continuing corporation, or in case of any sale or conveyance to another entity
of the property of the Company as an entirety or substantially as an entirety,





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or in the case of any statutory exchange of securities with another corporation
(including any exchange effected in connection with a merger of a third
corporation into the Company), the Holder of this Warrant shall have the right
thereafter to receive on the exercise of this Warrant the kind and amount of
securities, cash or other property which the Holder would have owned or have
been entitled to receive immediately after such reorganization,
reclassification, consolidation, merger, statutory exchange, sale or conveyance
had this Warrant been exercised immediately prior to the effective date of such
reorganization, reclassification, consolidation, merger, statutory exchange,
sale or conveyance and in any such case, if necessary, appropriate adjustment
shall be made in the application of the provisions set forth in this Section 3
with respect to the rights and interests thereafter of the Holder of this
Warrant to the end that the provisions set forth in this Section 3 shall
thereafter correspondingly be made applicable, as nearly as may reasonably be,
in relation to any shares of stock or other securities or property thereafter
deliverable on the exercise of this Warrant.  The above provisions of this
subsection 3(e) shall similarly apply to successive reorganizations,
reclassifications, consolidations,  mergers, statutory exchanges, sales or
conveyances.  The issuer of any shares of stock or other securities or property
thereafter deliverable on the exercise of this Warrant shall be responsible for
all of the agreements and obligations of the Company hereunder.  Notice of any
such reorganization, reclassification, consolidation, merger, statutory
exchange, sale or conveyance and of said provisions so proposed to be made,
shall be mailed to the Holders of the Warrants not less than 30 days prior to
such event.  A sale of all or substantially all of the assets of the Company
for a consideration consisting primarily of securities shall be deemed a
consolidation or merger for the foregoing purposes.

                 (f)      In case any event shall occur as to which the other
provisions of this Section 3 are not strictly applicable but as to which the
failure to make any adjustment would not fairly protect the purchase rights
represented by this Warrant in accordance with the essential intent and
principles hereof then, in each such case, the Holders of Warrants representing
the right to purchase a majority of the Warrant Shares subject to all
outstanding Warrants may appoint a firm of independent public accountants of
recognized national standing reasonably acceptable to the Company, which shall
give their opinion as to the adjustment, if any, on a basis consistent with the
essential intent and principles established herein, necessary to preserve the
purchase rights represented by the Warrants.  Upon receipt of such opinion, the
Company will promptly mail a copy thereof to the Holder of this Warrant and
shall make the adjustments described therein.  The fees and expenses of such
independent public accountants shall be borne by the Company.
                 
                 (g)      No adjustment in the Per Share Warrant Price shall be
required unless such adjustment would require an increase or decrease of at
least $0.05 per share of Common Stock; provided, however, that any adjustments
which by reason of this Subsection 3(g) are not required to be made shall be
carried forward and taken into account in any subsequent adjustment.  All
calculations under this Section 3 shall be made to the nearest cent or to the
nearest 1/100th of a share, as the case may be.  Anything in this Section 3 to
the contrary notwithstanding, the Company shall be entitled to make such
reductions in the Per Share Warrant Price, in addition to those required by
this Section 3, as it in its discretion shall deem





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to be advisable in order that any stock dividend, subdivision of shares or
distribution of rights to purchase stock or securities convertible or
exchangeable for stock hereafter made by the Company to its stockholders shall
not be taxable.

                 (h)      Whenever the Per Share Warrant Price is adjusted as
provided in this Section 3 and upon any modification of the rights of a Holder
of Warrants in accordance with this Section 3, the Chief Financial Officer of
the Company shall promptly prepare a certificate setting forth the Per Share
Warrant Price and the number of Warrant Shares after such adjustment or the
effect of such modification and a brief statement of the facts requiring such
adjustment or modification and the manner of computing the same and cause
copies of such certificate to be mailed to the Holders of the Warrants.

                 (i)      If the Board of Directors of the Company shall
declare any dividend or other distribution with respect to the Common Stock,
the Company shall mail notice thereof to the Holders of the Warrants not less
than 15 days prior to the record date fixed for determining stockholders
entitled to participate in such dividend or other distribution.

                 (j)      If, as a result of an adjustment made pursuant to
this Section 3, the Holder of any Warrant thereafter surrendered for exercise
shall become entitled to receive shares of two or more classes of capital stock
or shares of Common Stock and other capital stock of the Company, the Board of
Directors (whose determination shall be conclusive and shall be described in a
written notice to the Holder of any Warrant promptly after such adjustment)
shall determine the allocation of the adjusted Per Share Warrant Price between
or among shares or such classes of capital stock or shares of Common Stock and
other capital stock.

                 4.       REDEMPTION.  At any time after September 25,1997, 
this Warrant shall be redeemable at the Company's option upon forty five (45)
days notice to the Holder, for $.01 per Warrant Share, if the closing price of
the Common Stock of the Company shall exceed three hundred percent (300%) (as
reported on the Nasdaq Small Cap Market) of the Exercise Price of this Warrant
for twenty (20) consecutive trading days ending ten (10) days prior to the date
of notice of redemption.

                  5.      FULLY PAID STOCK; TAXES.  The Company agrees that the
shares of the Common Stock represented by each and every certificate of Warrant
Shares delivered on the exercise of this Warrant be validly issued and
outstanding, fully paid and nonassessable, and not subject to preemptive rights
or rights of first refusal, and the Company will take all such actions as may
be necessary to assure that the par value or stated value, if any, per share of
the Common Stock is at all times equal to or less than the then Per Share
Warrant Price.  The Company further covenants and agrees that it will pay, when
due and payable, any and all Federal and state stamp, original issue or similar
taxes which may be payable in respect of the issue of any Warrant Share or any
certificate thereof.





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                 6.       REGISTRATION UNDER SECURITIES ACT OF 1933.

                 (a)      The shares of Common Stock underlying the Warrants
(the "Conversion Shares") shall be included in the registration statement filed
in connection with the Private Placement or, if no such registration statement
is filed or becomes effective, in the next registration statement (the
"Registration Statement") filed by the Company in which these shares can
legally be included (i.e. excluding registrations on Form S-4, S-8 or any other
limited purpose form), such Registration Statement to be completed no later
that 240 days from the date of this Agreement.

                 (b)      Until all Warrant Shares have been sold under a
Registration Statement or pursuant to Rule 144, the Company shall use its
reasonable best efforts to file with the Securities and Exchange Commission all
current reports and the information as may be necessary to enable the Holder to
effect sales of its shares in reliance upon Rule 144 promulgated under the Act.

                 7.       LIMITED TRANSFERABILITY.  This Warrant may not be
sold, transferred, assigned or hypothecated by the Holder except in compliance
with the provisions of the Act and the applicable state securities "blue sky"
laws.  The Company may treat the registered Holder of this Warrant as he or it
appears on the Company's books at any time as the Holder for all purposes.  The
Company shall permit any Holder of a Warrant or his duly authorized attorney,
upon written request during ordinary business hours, to inspect and copy or
make extracts from its books showing the registered holders of Warrants.  All
warrants issued upon the transfer or assignment of this Warrant will be dated
the same date as this Warrant, and all rights of the holder thereof shall be
identical to those of the Holder.

                 8.       LOSS, ETC., OF WARRANT.  Upon receipt of evidence
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant, and of indemnity reasonably satisfactory to the Company, if lost,
stolen or destroyed, and upon surrender and cancellation of this Warrant, if
mutilated, the Company shall execute and deliver to the Holder a new Warrant of
like date, tenor and denomination.

                 9.       WARRANT HOLDER NOT SHAREHOLDER.  Except as otherwise
provided herein, this Warrant does not confer upon the Holder any right to vote
or to consent to or receive notice as a stockholder of the Company, as such, in
respect of any matters whatsoever, or any other rights or liabilities as a
stockholder, prior to the exercise hereof.

                 10.      MODIFICATION.    This Agreement may not be modified,
amended or waived in any manner except by an instrument in writing signed by
_____________________________________________________________________, and the
Company.  The waiver by either party of compliance with any provision of this
Agreement by the other party shall not operate or be construed as a waiver of
such party of a provision of this Agreement.





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                 11.      COMMUNICATION.  No notice or other communication
under this Warrant shall be effective unless, but any notice or other
communication shall be effective and shall be deemed to have been given if, the
same is in writing and is mailed by first-class mail, postage prepaid,
addressed to:

                 (a)      the Company at 2425 North 55th Street, Boulder, CO
80301, Attention: President or other address as the Company has designated in
writing to the Holder; or

                 (b)      the Holder at _______________________________________
______________________________________________________________ or other such
address as the Holder has designated in writing to the Company.

                 12.      HEADINGS.  The headings of this Warrant have been
inserted as a matter of convenience and shall not affect the construction
hereof.

                 13.      APPLICABLE LAW.  This Warrant shall be governed by
and construed in accordance with the law of the State of New York without
giving effect to the principles of conflicts of law thereof.





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                 IN WITNESS WHEREOF, the Company has caused this Warrant to be
signed by its President and its corporate seal to be hereunto affixed and
attested by its Secretary this 25th day of SEPTEMBER, 1997.

           
                                                XENOMETRIX, INC.



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

ATTEST:


----------------------------
         Secretary

[Corporate Seal]





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                                  SUBSCRIPTION

                 The undersigned, ___________________, pursuant to the
provisions of the foregoing Warrant, hereby agrees to subscribe for and
purchase ____________________ shares of the Common Stock, par value $.001 per
share, of Xenometrix, Inc. covered by said Warrant, and makes payment therefor
in full at the price per share provided by said Warrant.

Dated:                                Signature:
      ----------------                          ----------------------------

                                      Address:
                                                ----------------------------


                               CASHLESS EXERCISE

                 The undersigned ___________________, pursuant to the
provisions of the foregoing Warrant, hereby elects to exchange its Warrant for
___________________ shares of Common Stock, par value $.001 per share, of
Xenometrix, Inc.  pursuant to the Cashless Exercise provisions of the Warrant.

Dated:                                Signature:
      ----------------                          ----------------------------

                                      Address:
                                                ----------------------------



                                   ASSIGNMENT

                 FOR VALUE RECEIVED _______________ hereby sells, assigns and
transfers unto ____________________ the foregoing Warrant and all rights
evidenced thereby, and does irrevocably constitute and appoint
_____________________, attorney, to transfer said Warrant on the books of
Xenometrix, Inc.


Dated:                                Signature:
      ----------------                          ----------------------------

                                      Address:
                                                ----------------------------





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                               PARTIAL ASSIGNMENT

                 FOR VALUE RECEIVED _______________ hereby assigns and
transfers unto ____________________ the right to purchase _______ shares of the
Common Stock, par value $.001 per share, of Xenometrix, Inc. covered by the
foregoing Warrant, and a proportionate part of said Warrant and the rights
evidenced thereby, and does irrevocably constitute and appoint
____________________, attorney, to transfer that part of said Warrant on the
books of Xenometrix, Inc.

Dated:                                Signature:
      ----------------                          ----------------------------

                                      Address:
                                                ----------------------------





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