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                                  EXHIBIT 10.47


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.


                      WARRANT FOR THE PURCHASE OF SHARES OF
                                  COMMON STOCK

NO. 128                                                         55,833 SHARES

            FOR VALUE RECEIVED, XENOMETRIX, INC., a Delaware corporation (the
"COMPANY"), hereby certifies that THE ARIES FUND, A CAYMAN ISLANDS TRUST, 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"), 55,832 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 


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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.

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 


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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 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.



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            (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 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.


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            (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, 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 


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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 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 JANUARY 12, 1998, 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 


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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.

            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 Paramount
Capital Asset Management, Inc. the Investment Manager of The Aries Fund, a
Cayman Island 


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Trust, 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.

            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 c/o Paramount Capital Asset Management, Inc., 787
Seventh Avenue, New York, NY, 10019, Attn: Lindsay A. Rosenwald, M.D. 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 12th day of JANUARY, 1998.


                                    XENOMETRIX, INC.



                                    By: --------------------------------
                                      Name:
                                      Title: President & Chief Executive Officer

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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