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                                                                   Exhibit 10.55

                            STOCK PURCHASE AGREEMENT

     THIS AGREEMENT is made and entered as of the 16th day of June, 1997, by and
between POLAR MOLECULAR CORPORATION, a Utah corporation (the "Company") and
Gerald A. Goray, Trustee ("Purchaser") pursuant a Trust Agreement dated January
30, 1984, as amended.

                                   WITNESSETH:

     WHEREAS, pursuant to the terms and conditions of this Agreement, the
Company desires to sell and Purchaser desires to purchase shares of the common
stock of the Company, par value $.001 per share.

     NOW THEREFORE, in consideration of the premises and of the mutual covenants
and conditions herein contained, the parties agree as follows:

     1. Purchase of Stock. Subject to the terms and conditions of this Agreement
and based upon the warranties and representations herein contained, the Company
agrees to sell to Purchaser for a purchase price of $.20 per share, an aggregate
of 1,000,000 shares of the common stock, par value $.001 per share, of the
Company (the "Shares").

     2. Representations and Warranties of the Company. The Company represents
and warrants that:

          2.01 Organization and Good Standing. The Company is a corporation duly
organized, validly existing and in good standing under the laws of the State of
Utah and has all requisite corporate power and is duly authorized, qualified,
franchised and licensed under all applicable laws, regulations, ordinances and
orders of public authorities to own its properties and assets and to carry on
its business as it is presently being conducted.

          2.02 Capitalization. The authorized capital stock of the Company
consists of 75,000,000 shares of common stock, with $.001 par value. All
outstanding shares are duly authorized, fully paid, validly issued and
non-assessable in accordance with applicable law. No dividends or other
distribution of the assets of the Company have been declared or paid in the
capital stock of the Company. 62,007,378 shares of said common stock are issued
and outstanding as of the date hereof.

          2.03 Authorization. The Board of Directors of the Company has approved
this Agreement and the transactions contemplated hereby and has authorized the
execution and delivery of this Agreement by the Company. The Company has full
power, authority and legal right to enter into this Agreement and to consummate
the transactions contemplated hereby and this Agreement constitutes a legal,
valid and binding obligation of the Company enforceable in accordance with its
terms.

          2.04 Litigation. There is no action, suit proceeding or investigation
pending, at law or in equity, or to the knowledge of the Company's management,
threatened, against or affecting the Company before or in any court, either
state or Federal, public board, or body which calls into question the creation,
organization or existence of the Company, the validity of this Agreement or the
authority of the Company to execute, deliver and carry out the terms of

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this Agreement or which judgment, order or finding can reasonably be expected to
have a material adverse effect on the condition (financial or otherwise) of the
Company. The Company has no knowledge of any default on its part with respect to
any judgment, order, writ, injunction, decree, award, rule or regulation of any
court, arbitrator or governmental agency or instrumentality.

          2.05 Subsidiaries. The Company does not own, directly or indirectly,
any interest or investment, whether equity or debt, in any corporation,
business, trust or other entity.

          2.06 Compliance with Law and Other Instruments. The Company is not in
violation or default of any term of its Articles of Incorporation or Bylaws, or
of any agreement, contract, commitment, instrument, indenture, judgment, decree
or order applicable to it and has timely filed all reports and any other
documents required by it to be filed with a governmental agency. The execution,
delivery and performance of this Agreement and the taking of action contemplated
hereby will not result in any violation of or be in conflict with or constitute
a default under (a) the Articles of Incorporation or By-Laws of the Company, or
(b) any material agreement or instrument to which the Company or any
consolidated subsidiary is a party or by which the Company is subject, or result
in the creation of any material lien, charge or encumbrance on any of the
properties of the Company.

          2.07 Contracts and Commitments. The Company is not a party to any
contract, agreement, other commitment or instrument or subject to any charter or
other corporate restriction or any judgment, order, writ, injunction, decree or
award which materially and adversely affects, the business, operations,
properties, assets or condition of the Company.

          2.08 Tax Returns. Within the times and in the manner prescribed by
law, the Company has filed all federal, state and local tax returns required by
law and has paid all taxes, assessments and penalties due and payable. All taxes
and governmental charges levied or assessed against the property or the business
of the Company have been paid, other than taxes or charges the payment of which
is not yet due or which, if due, is not yet delinquent or is being contested in
good faith or has not been finally determined.

          2.09 Brokers. The Company agrees to indemnify and hold Purchaser
harmless from and against any fee, loss or expense arising out of claims by
brokers or finders employed or alleged to have been employed by it with respect
to the transactions contemplated by this Agreement.

          2.10 Patent. The Company is the owner of certain patents ("Patents")
pursuant to a Patent Assignment Agreement dated April 1, 1997 ("Agreement"),
which Agreement is incorporated herein by reference. Said Agreement is in full
force and effect, the Company is not in default with respect to any provisions
in said Agreement and the Company shall use its best efforts to comply with the
conditions of said Agreement and maintain its rights and benefits pursuant to
such Agreement. It is understood and agreed by the Company that said Patents
constitute a valuable asset of the Company and that any additional U.S. or
foreign patents obtained by any officer, director, shareholder, employee or
agent of the Company which modifies, improves or is related to said Patents or
related technology, shall also be the property of the Company or in the case of
any new patents or technology obtained by or developed by

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Otis L. Nelson, Mark L. Nelson or A. Richard Nelson such new patents or
technology shall be exclusively licensed to the Company with worldwide
manufacturing and marketing rights belonging to the Company.

          2.11 Dilution of Shares. The Company hereby agrees that if at any time
it issues any additional Shares in the Company, Purchaser shall be given the
right to purchase shares at the same price and terms as the Company issues any
such additional Shares. The number of Shares Purchaser shall be entitled to
purchase shall be such amount as necessary to maintain Purchaser's pro-rata
ownership percentage interest in the Company's outstanding Shares. Purchaser
shall be given written notice of the Company's intention to issue additional
Shares and the terms and price thereof and Purchaser shall have 30 days to elect
to exercise its right to purchase Shares per this paragraph. If such additional
Shares are issued in consideration of services or property, such services or
property shall be appraised by an independent qualified appraiser and such
appraisal shall be used as the basis for determining the price of such Shares.

     3. Representations and Warranties of Purchaser:

          3.01 Investment Representations: Purchaser represents and warrants to
the company that:

               (a) The Purchaser has been informed that the sale of the Shares
     hereunder is being made without registration under the Securities Act of
     1933 (the "Act") or any state securities laws and that the Shares may not
     be sold or transferred without registration under the Act or unless an
     exemption from such registration is available.

               (b) Purchaser is acquiring the Shares for its own account, no one
     else has a beneficial interest in the Shares and Purchaser does not intend
     to and will not resell the Shares unless, at a future date, they are
     registered under the Act or a specific exemption from registration is
     available to Purchaser in connection with any such resale. Purchaser
     understands that an exemption from such registration may be available
     pursuant to Rule 144 promulgated under the Act by the Securities and
     Exchange Commission ("Commission") but that in no event may Purchaser sell
     the Shares pursuant to Rule 144 prior to the expiration of a two-year
     period after Purchaser has acquired the Shares and a minimum three-year
     holding period may be required in some cases; and that any sales pursuant
     to Rule 144 can only be made in full compliance with the provisions
     thereof.

               (c) Purchaser understands that each certificate representing the
     Shares will bear on its face a legend in substantially the following form:

          "The Shares represented by this Certificate have not been registered
     under the Securities Act of 1933 ("Act"). The Shares have been acquired for
     investment and no sale, transfer or hypothecation of the Shares or any
     interest therein may be made except pursuant to an effective registration
     statement under the Act unless the Company has received an opinion of
     counsel to the Company that such transfer does not require registration
     under the Act."

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          Purchaser further understands that the Company may place a stop
     transfer order pertaining to the certificates evidencing the Shares with
     the transfer agent to the same effect as such restrictive legend.

               (d) Purchaser has such knowledge and experience in financial and
     business matters that it is capable of evaluating the merits and risks of
     Purchaser's investment in the Shares or has obtained the advice of any
     attorney, certified public accountant or registered investment advisor with
     respect to the merits and risks of his investment in the Shares. Purchaser
     understands that the Company is subject to all of the risks inherent in a
     development stage business and additional risks that are inherent in the
     Company's business. Purchaser has taken full cognizance of and understands
     those risks and the effect they may have on the Purchaser's investment.

               (e) The Purchaser has been provided with copies of the Company's
     Financial Statements dated March 31, 1997, prepared by Marrs, Rudnick &
     Sevier, LLC and such other financial and other information regarding the
     Company that Purchaser deemed necessary. The Company represents that such
     information is true and correct.

               (f) The Purchaser has been informed that the proceeds from the
     sale of the Shares will be used by the Company for general working capital
     purposes. It is agreed by the Company that such proceeds shall be used in
     particular for the following purposes: commence accounting work to prepare
     the Company for an initial public offering of its Shares, the hiring of
     Chandra Prakash to represent the Company in general and to market the
     Company's products in India, to pay legal fees and related fees in
     connection with the preparation of the Company for an initial public
     offering of its Shares and to evaluate the Octel Associates, acquisition
     opportunity.

               (g) The Purchaser has been provided with the opportunity to ask
     questions of, and receive answers from, the Company and its officers,
     employees and agents concerning the business and financial condition of the
     Company and Purchaser has received satisfactory answers to any such
     questions and has no further questions at this time.

               (h) The Purchaser understands that his investment in the Shares
     and the Company is speculative and may remain so for an indefinite period,
     that substantial additional investments in the Company may be required and
     that there is no assurance that any such additional investments can be
     obtained, and acknowledges that it is able to bear the economic risk of its
     investment in the Shares should it be determined ultimately to the
     worthless.

          3.2 Authorization. The execution of this Agreement has been duly
authorized by Purchaser and this Agreement is binding upon Purchaser in
accordance with its terms.

     4. Survival of Agreements. All covenants, agreements, representations and
warranties made herein shall survive execution and delivery of this Agreement
and the Closing hereunder.

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     5. Notices. All notices, requests, consents and other communications herein
shall be in writing and shall be mailed by certified mail, return receipt
requested, postage prepaid or delivered by Federal Express, or personally
delivered to the address set below each party's signature to this Agreement or
such other addresses as each of the parties hereto may provide from time to time
in writing to the other parties. Any such notice or communication shall be
deemed to have been given as of the date so delivered, mailed or telegraphed.

     6. Modifications, Waiver. No modification or waiver of any provision of
this Agreement or consent to any departure therefrom shall be effective unless
in writing and approved by all of the parties hereto.

     7. Entire Agreement. This Agreement contain the entire agreement between
the parties with respect to the transactions contemplated hereby, and supersedes
all negotiations, agreements, representations, warranties, commitments whether
in writing or oral, prior to the date hereof. Nothing in this Agreement shall be
construed or is intended to impose any personal liability on Gerald A. Goray or
the Gerald A. Goray Trust.

     8. Successors and Assigns. All of the terms of this Agreement shall be
binding upon and inure to the benefit of and be enforceable by the respective
successors and assigns of the parties hereto. Notwithstanding the foregoing,
Purchaser may not assign his rights under this Agreement without the written
consent of the Company.

     9. Execution and Counterparts. This Agreement may be executed in any number
of counterparts, each of which when so executed and delivered shall be deemed
any original, and such counterparts together shall constitute one instrument.
Each party shall receive a duplicate original of the counterpart copy or copies
executed by it.

     10. Governing Law and Forum. This Agreement shall be governed by the laws
of the State of Michigan.

     11. Severability. In the event any provision of this Agreement or the
application of such provision to any party shall be held by a court of competent
jurisdiction to be contrary to law, the remaining provisions of this Agreement
shall remain in full force and effect.

     12. Reports: The Company agrees to provide Purchaser with data and reports
at least quarterly with respect to its financial condition, marketing efforts,
technology status and initial public offering status.

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     IN WITNESS WHEREOF, the parties hereto have executed this Agreement by
persons thereunto duly authorized as of the date first above written.

PURCHASER                                  POLAR MOLECULAR CORPORATION


/s/ Gerald A. Goray                        By:  /s/ Mark L. Nelson
----------------------------------              --------------------------------
Gerald A. Goray, Trustee                   Its: President
621 NW 53rd Street, Suite 255                   4600 S. Ulster Street, Suite 700
Boca Raton, FL 33487                            Denver, CO 80237

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