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                                                                   EXHIBIT 10.28

                        CELL ROBOTICS INTERNATIONAL, INC.

                            2002 STOCK PURCHASE PLAN

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                        CELL ROBOTICS INTERNATIONAL, INC.

                            2002 STOCK PURCHASE PLAN

1.       PURPOSE.

         The purpose of this Plan is to provide an opportunity for Eligible
Participants of the Company and its Designated Subsidiary to purchase Common
Stock of the Company and thereby to have an additional incentive to contribute
to the prosperity of the Company. The Company makes no undertaking nor
representation to qualify the Plan as an "Employee Stock Purchase Plan" under
Section 423 of the Code.

2.       DEFINITIONS.

         (a)      "Board" shall mean the Board of Directors of the Company.

         (b)      "Code" shall mean the United States Internal Revenue Code of
1986, as amended.

         (c) "Committee" shall mean such committee as may be appointed by the
Board from time to time in accordance with Section 12 of this Plan, or if no
such committee is appointed, the entire Board.

         (d) "Common Stock" shall mean the common stock of the Company, par
value $.004 per share, or any stock into which such common stock may be
converted.

         (e)      "Company" shall mean Cell Robotics International, Inc., a
Colorado corporation.

         (f) "Compensation" shall mean an Employee's wages or salary and other
amounts payable to an Employee on account of personal services rendered by the
Employee to the Company or a Designated Subsidiary and which are reportable as
wages or other compensation on the Employee's Form W-2, plus pre-tax
contributions of the Employee under a cash or deferred arrangement (401(k) plan)
or cafeteria plan maintained by the Company or a Designated Subsidiary, but
excluding, however, (a) non-cash fringe benefits, (b) special payments as
determined by the Committee (e.g., moving expenses, unused vacation, severance
pay), (c) income from the exercise of stock options or other stock purchases and
(d) any other items of Compensation as determined by the Committee.

         (g)      "Consultant" shall mean a consultant or advisor who performs
bona fide services to the Company or a Designated Subsidiary.

         (h) "Designated Subsidiary" shall mean a Subsidiary which has been
designated by the Board or the Committee as eligible to participate in this
Plan.

         (i)      "Director" shall mean an individual serving as a member on the
Board.

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         (j) "Eligible Participants" shall mean those Employees, Consultants and
Directors who are selected by the Committee to be eligible to purchase shares of
Common Stock under Section 3 of this Plan.

         (k) "Employee" shall mean an individual classified as an employee
(within the meaning of Section 3401(c) of the Code and the regulations
thereunder) by the Company or a Designated Subsidiary on the Company payroll
records during the relevant participation period.

         (l)      "Exercise Period" shall mean a three-month, six-month or other
period as determined by the Committee.

         (m) "Fair Market Value" shall mean such amount as the Board, in its
sole discretion, shall determine; provided, however, that if there is a public
market for the securities, the Fair Market Value shall be the mean of the
highest and lowest sale prices of the securities per share or unit, as the case
may be, as reported in the Wall Street Journal (or, if not so reported, as
otherwise reported by the National Association of Securities Dealers Automated
Quotation System) as of the date in question or, in the event the securities are
listed on a stock exchange, the Fair Market Value shall be the meant of the
highest and lowest sale prices of the securities per share or unit, as the case
may be, on such exchange, as reported in the Wall Street Journal, as of the date
in question.

         (n)      "Participant" shall mean a participant in this Plan as
described in Section 4 of this Plan.

         (o)      "Plan" shall mean this Cell Robotics International, Inc. 2002
Stock Purchase Plan, as amended from time to time.

         (p) "Shareholder" shall mean a record holder of shares entitled to vote
shares of Common Stock under the Company's Bylaws.

         (q) "Subsidiary" shall mean any corporation or other entity (other than
the Company) in an unbroken chain of corporations or entities beginning with the
Company.

3.       ELIGIBILITY.

         3.1 Any Employee regularly employed on a full-time or part-time basis
by the Company or by the Designated Subsidiary shall be eligible to participate
in this Plan. Any Director and any Consultant shall also be eligible to
participate in this Plan; provided that any such Consultant shall either (a)(i)
be an individual within the meaning of General Instruction A of the Registration
Statement on Form S-8 and (ii) performs bona fide services to the Company or a
Designated Subsidiary and such services are not in connection with the offer or
sale of securities of the Company in a capital-raising transaction, and do not
directly or indirectly promote or maintain a market for the Company's securities
or (b) be otherwise eligible for issuance of securities to consultants or
advisors on a Registration Statement on Form S-8, or any successor form. The
Committee may establish administrative rules requiring that employment, in the
case of an Employee, or service, in the case of a Director or Consultant,
commence some


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minimum period (e.g., one pay period) prior to being eligible to participate in
this Plan. The Committee may also determine that a designated group of highly
compensated Employees (e.g., Employees subject to Section 16(b) of the
Securities Exchange Act of 1934, as amended (the "Exchange Act")) are ineligible
to participate in this Plan. The Committee may impose such restrictions on
eligibility and participation of Employees who are officers and directors to
facilitate compliance with federal or state securities laws or foreign laws.

         3.2 The Committee may determine that Directors, a designated group of
highly compensated Employees, Employees who are officers (e.g., persons subject
to Section 16(b) of the Securities Exchange Act of 1934, as amended (the
"Exchange Act")) are ineligible to participate in this Plan. The Committee may
impose such restrictions on eligibility and participation of Employees,
Consultants and Directors to facilitate compliance with federal or state
securities laws or foreign laws.

4.       PARTICIPATION.

         4.1 An Eligible Participant may become a Participant by filing, on a
date prescribed by the Committee, a Plan enrollment form required by the
Committee and, in the case of an Employee, a completed payroll deduction
authorization. An Eligible Participant who is an Employee may authorize payroll
deductions at the rate of any whole percentage of the Employee's Compensation,
not to exceed such percentage as specified from time to time by the Committee.
All such payroll deductions or other amounts paid by any Participant under the
Plan may be held by the Company and commingled with its other corporate funds.
No interest shall be paid or credited to the Participant with respect to such
payroll deductions or otherwise except where required by local law as determined
by the Committee. The Committee may establish, or cause to be established, a
separate bookkeeping account for each Participant. A Participant may not make
any additional payments into such account unless authorized by the Committee.

         4.2 A Participant who is an Employee may suspend or discontinue
participation in this Plan or increase or decrease his or her rate of payroll
deductions at any time under procedures established by the Committee; provided
that the Committee may impose a reasonable time period prior to end of any
payroll period in which such election must be made in order to be effective with
respect to that pay period and any election to increase or decrease a
Participant's rate of payroll deductions shall only be effective by filing a new
payroll deduction authorization and Plan enrollment form. If a new payroll
deduction authorization and Plan enrollment form is not filed with the Company,
the rate of payroll deductions shall continue at the originally elected rate
unless the Committee determines to change the permissible rate.

         4.3 In the event any Participant terminates employment with the Company
or any Subsidiary for any reason (including death) at any time before the
expiration of an Exercise Period, the Participant's participation in this Plan
shall terminate and all amounts credited to the Participant's account shall be
paid to the Participant or the Participant's estate without interest (except
where required by local law). Whether a termination of employment or service has
occurred shall be determined by the Committee. The Committee may also establish
rules regarding when leaves of absence or change of employment status (e.g.,
from full-time to part-time) will be considered to be a termination of
employment, and the Committee may establish


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termination of employment procedures for this Plan which are independent of
similar rules established under other benefit plans of the Company and its
Designated Subsidiary.

5.       OFFERING.

         5.1 The maximum number of shares of Common Stock which may be issued
pursuant to this Plan shall be 2,000,000 shares, subject to adjustment as
specified in Section 8. Each Exercise Period shall be determined by the
Committee. The Committee shall have the power to change the duration of future
Exercise Periods, establish different Exercise Periods for each Participant or
extend Exercise Periods.

         5.2 With respect to each Exercise Period, each Eligible Participant who
has elected to participate as provided in Section 4.1 shall be granted an option
to purchase that number of shares of Common Stock which may be purchased during
the Exercise Period with the value of the services rendered by the Participant
or, in the case of a Participant who is an Employee, payroll deductions
designated by such Employee, at the purchase price specified in Section 5.3
below.

         5.3 The purchase price under each option shall be a percentage
established from time to time by the Committee of the Fair Market Value of the
Common Stock on the date on which the Common Stock is purchased, the date the
Participant enrolls in this Plan or such other date specified by the Committee.
The purchase price shall be established by the Committee and the Committee shall
in its sole discretion determine the value of services being rendered by any
Participant or other amount, property, services or obligations contributed by
the Participant for the purchase of the Common Stock. The value of any services
provided a Participant to purchase Common Stock or the amount of payroll
deductions of any Employee who is a Participant used to purchase Common Stock,
shall be received or retained by the Company as full payment for the Common
Stock and the Common Stock shall then be fully paid and non-assessable.

6.       PAYMENT AND DELIVERY.

         Unless the Committee determines otherwise, an Eligible Participant may
exercise an option at any time during the Exercise Period. Upon the exercise of
an option, the Company shall deliver to the Participant the Common Stock
purchased in accordance with this Plan and the elections made by such
Participant. In no event shall a Participant be entitled to exercise any option
for the purchase of fractional shares. To the extent the unused cash balance
represents a fractional share, the unused cash balance shall be carried over to
the next Exercise Period, if the Participant is also a Participant in this Plan
at that time or refunded to the Participant, as determined by the Committee. The
Committee may permit or require that shares be deposited directly with a broker
designated by the Participant (or a broker selected by the Committee) or to a
designated agent of the Company, and the Committee may utilize electronic or
automated methods of share transfer. The Committee may require that shares be
retained with such broker or agent for a designated period of time (and may
restrict dispositions during that period) and/or may establish other procedures
to permit tracking of dispositions of such shares or to restrict transfer of
such shares. No Participant shall have any voting, dividend, or other
shareholder


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rights with respect to shares subject to any option granted under this Plan
until the option has been exercised and shares issued.

7.       EXPIRATION OF EXERCISE PERIOD.

         Upon the expiration of each Exercise Period, to the extent unexercised
(a) a Participant that is an Employee shall be deemed to have automatically
exercised his option for the purchase of that number of full shares of Common
Stock which the accumulated payroll deductions credited to the Participant's
account at that time shall purchase at the applicable price specified in Section
5.3 and (b) a Participant that is a Consultant or a Director shall be deemed to
have terminated his option for the purchase of any shares of Common Stock
subject to such option.

8.       RECAPITALIZATION.

         If after the grant of an option, but prior to the purchase of Common
Stock under the option, there is any increase or decrease in the number of
outstanding shares of Common Stock because of a stock split, stock dividend,
combination or recapitalization of shares subject to options, the number of
shares to be purchased pursuant to an option, the maximum number of shares
specified in Section 5.1 shall be proportionately increased or decreased, the
terms relating to the purchase price with respect to the option shall be
appropriately adjusted by the Committee, and the Committee shall take any
further actions which, in the exercise of its discretion, may be necessary or
appropriate under the circumstances. The Committee, if it so determines in the
exercise of its sole discretion, also may adjust the number of shares specified
in Section 5.1, as well as the price per share of Common Stock covered by each
outstanding option and the maximum number of shares subject to any individual
option, in the event the Company effects one or more reorganizations,
recapitalizations, spin-offs, split-ups, rights offerings or reductions of
shares of its outstanding Common Stock. The Committee's determinations under
this Section 8 shall be conclusive and binding on all parties.

9.       MERGER, LIQUIDATION, OTHER COMPANY TRANSACTIONS.

         9.1      In the event of the proposed liquidation or dissolution of the
Company, any outstanding option grants will terminate immediately prior to the
consummation of such proposed transaction, unless otherwise provided by the
Committee in its sole discretion, and all outstanding options shall
automatically terminate and the amounts of all payroll deductions remaining in
the Participants' accounts will be refunded without interest to the applicable
Participants.

         9.2      In the event of a proposed sale of all or substantially all of
the assets of the Company, or the merger or consolidation of the Company with or
into another corporation, then in the sole discretion of the Committee, (a) each
option shall be assumed or an equivalent option shall be substituted by the
successor corporation or parent or subsidiary of such successor corporation, or
(b) a date established by the Committee on or before the date of consummation of
such merger, consolidation or sale shall be treated as an option termination
date, and, at the Committee's sole discretion, all outstanding options shall be
deemed void or exercisable on such date. To the extent the option is deemed void
under this Section 9.2, the amounts of all payroll


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deductions remaining in the Participants' accounts will be refunded without
interest to the applicable Participants.

10.      TRANSFERABILITY.

         Options granted to Participants may not be voluntarily or involuntarily
assigned, transferred, pledged, or otherwise disposed of in any way, and any
attempted assignment, transfer, pledge, or other disposition shall be null and
void and without effect. If a Participant in any manner attempts to transfer,
assign or otherwise encumber his or her rights or interest under this Plan, such
act shall be treated as an election by the Participant to discontinue
participation in this Plan pursuant to Section 4.2.

11.      AMENDMENT OR TERMINATION OF THE PLAN.

         11.1     This Plan shall continue until, September 30, 2004, unless
previously terminated in accordance with Section 11.2.

         11.2     The Board may, in its sole discretion, insofar as permitted by
law, terminate or suspend this Plan, or revise or amend it in any respect
whatsoever, except that, without approval of the shareholders, no such revision
or amendment shall:

                  (a)      be made if shareholder approval is required by
applicable law or any listing standards of any exchange or market in which the
Common Stock is listed or trades; or

                  (b)      amend this Section 11.2 to defeat its purpose.

12.      ADMINISTRATION.

         The Board may elect to administer this Plan or the Board shall appoint
a Committee consisting of at least two members, each of whom shall be a member
of the Board who is a Non-Employee Director, within the meaning of Rule 16b-3
promulgated under the Exchange Act. The Board may also require that each member
of the Committee be an Outside Director, within the meaning of Section 162(m) of
the Code. The members of the Committee will serve for such period of time as the
Board may specify and may be removed by the Board at any time. This Plan shall
be administered by, or under the direction of, the Committee constituted in such
a manner as to comply at all times with Rule 16b-3 (or any successor rule) under
the Exchange Act. The Committee will have the authority and responsibility for
the day-to-day administration of this Plan, the authority and responsibility
specifically provided in this Plan and any additional duty, responsibility and
authority delegated to the Committee by the Board, which may include any of the
functions assigned to the Board in this Plan. The Committee shall have full
power and authority to promulgate any rules and regulations which it deems
necessary for the proper administration of this Plan, to interpret the
provisions and supervise the administration of this Plan, and to take all action
in connection with administration of this Plan as it deems necessary or
advisable, consistent with the delegation from the Board. Decisions of the Board
and the Committee shall be final and binding upon all Participants. Any decision
reduced to writing and signed by a majority of the members of the Committee
shall be fully effective as if it had been


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made at a meeting of the Committee duly held. The Company shall pay all expenses
incurred in the administration of this Plan. No Board or Committee member shall
be liable for any action or determination made in good faith with respect to
this Plan or any option granted thereunder.

13.      COMMITTEE RULES FOR NON-UNITED STATES JURISDICTIONS.

         The Committee may adopt rules or procedures relating to the operation
and administration of this Plan in non-United States jurisdictions to
accommodate the specific requirements of local laws and procedures. Without
limiting the generality of the foregoing, the Committee is specifically
authorized to adopt rules and procedures regarding handling of payroll
deductions, payment of interest, conversion of local currency, withholding
procedures and handling of stock certificates which vary with local
requirements.

14.      SECURITIES LAWS REQUIREMENTS.

         The Company shall not be under any obligation to issue Common Stock
upon the exercise of any option unless and until the Company has determined
that: (a) it and the Participant have taken all actions required to register the
Common Stock under the United States Securities Act of 1933, as amended, or to
perfect an exemption from the registration requirements thereof; (b) any
applicable listing requirement of any stock exchange on which the Common Stock
is listed has been satisfied; and (c) all other applicable provisions of state,
federal and applicable foreign law have been satisfied.

15.      GOVERNMENTAL REGULATIONS.

         This Plan and the Company's obligation to sell and deliver shares of
its stock under this Plan shall be subject to the approval of any governmental
authority required in connection with this Plan or the authorization, issuance,
sale, or delivery of stock hereunder.

16.      NO ENLARGEMENT OF EMPLOYEE RIGHTS.

         Nothing contained in this Plan shall be deemed to give any Employee the
right to be retained in the employ of the Company or any Designated Subsidiary
or to interfere with the right of the Company or Designated Subsidiary to
discharge any Employee at any time.

17.      GOVERNING LAW.

         THIS PLAN SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE
LAWS OF THE STATE OF NEW MEXICO, WITHOUT REGARD TO CONFLICT OF LAWS PRINCIPLES.

18.      EFFECTIVE DATE.

         This Plan shall become effective on September 27, 2002, the date of its
adoption by the Board.

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