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                                  EXHIBIT 10.10

                            STOCK PURCHASE AGREEMENT


         This STOCK PURCHASE AGREEMENT (the "Agreement") is made as of January
23, 2001, by and among Hollenshead Capital Management LLC, a Nevada limited
liability company (the "Purchaser"), BioSys, Inc., an Ohio corporation (the
"Company") and American Bio Medica Corporation, a New York corporation (the
"Shareholder").

         In consideration of the mutual promises, representations, warranties,
covenants and conditions set forth in this Agreement, the parties hereto agree
as follows:

         1.       Purchase and Sale of Common Stock; Purchase Price; Payment.

                  (a)      Purchase and Sale; Purchase Price. Subject to the
terms and conditions of this Agreement, the Purchaser shall purchase from the
Shareholder and the Shareholder shall sell, assign and transfer to the
Purchaser, at the Closing (as defined below) and as of the Closing Date (as
defined below), all right, title and interest of the Shareholder in and to the
57.57576 shares of common stock of the Company (the "Common Stock") held by the
Shareholder (the "Shares"), for an aggregate purchase price of Three Hundred
Eighty Thousand Dollars ($380,000) (the "Purchase Price").

                  (b)      Payment. At the Closing and on the Closing Date, the
Purchaser shall pay to the Shareholder the aggregate Purchase Price by certified
check, wire transfer or by other mutually agreeable manner.

         2.       Representations and Warranties of the Shareholder. The
Shareholder represents and warrants to the Purchaser on and as of the date
hereof and as of the Closing Date as follows:

                  (a)      Authorization of the Shareholder. The Shareholder has
full power and authority to execute and deliver this Agreement and to perform
its obligations hereunder. All action on the part of the Shareholder necessary
for the authorization, execution and delivery of this Agreement and for the
performance of all obligations of the Shareholder hereunder has been taken and
this Agreement constitutes valid and legally binding obligations of the
Shareholder, enforceable in accordance with its terms.

                  (b)      Issuance of and Title to Common Stock. The Common
Stock that is being purchased by the Purchaser hereunder is duly and validly
issued, fully paid, and nonassessable. The Shareholder is the record owner of,
and has good title to, the shares of Common Stock, free and clear of any liens,
claims, encumbrances, restrictions, agreements and defects of any kind or nature
whatsoever and, upon the sale and transfer by the Shareholder of its certificate
or certificates therefor to the Purchaser pursuant to this Agreement, the
Shareholder will confirm and vest in the Purchaser good and valid title to their
respective shares, free and clear of any and all claims, liens, charges,
encumbrances, restrictions, agreements and defects of any kind or nature
whatsoever.

                  (c)      Claims Against the Purchaser or the Company. The
Shareholder does not have any presently existing claim, demand, action or cause
of action, whether at law or in equity, whether accrued, contingent, fixed or
otherwise, which the Shareholder might hereafter attempt to assert against the
Purchaser or the Company or any of their respective attorneys, accountants,
parents, subsidiaries, affiliates, predecessors, officers, directors, employees
or stockholders, of any kind, character or description whatsoever, arising out
of, related to or in any manner connected with, either directly or indirectly,
their participation as an employee, director, officer or shareholder of the
Company, including but not limited (i) to any rights to purchase or receive
shares of Common Stock, (ii) presently existing claim or basis for a claim for
indemnification from the Company pursuant to the Company's articles of
incorporation or bylaws, or any agreement or law, or (iii) any loans or


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debt.

         3.       Representations and Warranties of the Company. The Company
represents and warrants to the Purchaser on and as of the date hereof and on and
as of the Closing Date as follows:

                  (a)      Organization of the Company. The Company is a
corporation duly organized, validly existing, and in good standing under the
laws of the State of Ohio and has all requisite corporate power and authority to
own and operate its properties and assets and to carry on its business as now
conducted and as proposed to be conducted. The Company is qualified to do
business in Ohio and Michigan.

                  (b)      Authorization of the Company. The Company has full
power and authority to execute and deliver this Agreement and to perform its
obligations hereunder. All action on the part of the Company necessary for the
authorization, execution and delivery of this Agreement and for the performance
of all obligations of the Company hereunder has been taken and this Agreement
constitutes valid and legally binding obligations of the Company, enforceable in
accordance with its terms.

                  (c)      Corporate Matters. The authorized shares of the
Company consists of 850 shares of Common Stock, of which 303.0303 shares have
been issued and are currently outstanding, and are owned by the shareholders in
the amounts listed on Schedule 3(c)(i). The directors and officers of the
Company are listed on Schedule 3(c)(ii). The Company does not own or control,
directly or indirectly, any interest in any other corporation, association, or
other business entity and the Company is not a participant in any joint venture,
partnership, or similar arrangement.

                  (d)      Options, Commitments, Agreements. Except for the
option granted to Peter Savarino whereby he has the right to acquire up to 1% of
the issued and outstanding shares of the Company, and other than rights held by
the Purchaser, there are no existing options, warrants, commitments or
agreements of any kind or nature whatsoever calling for or relating to the
issuance of the Common Stock or other securities of the Company, nor do there
exist any agreements, trusts or understandings relating to the voting,
redemption or transfer of Common Stock or other securities of the Company.

                  (e)      Intellectual Property.

                           (i)  The Company has good and marketable title to all
                  rights, title, and interest in and to all of the Company's
                  Intellectual Property (as defined below), and such
                  Intellectual Property is free and clear of any claims of
                  former or present employees, agents, consultants or
                  contractors or other persons or entities and is not subject to
                  any liens. The term "Intellectual Property" shall mean all
                  intellectual property rights, including, without limitation,
                  (i) all trademark and service mark registrations and
                  applications therefor and all trade names, trademarks and
                  service marks, whether or not registered or registrable; (ii)
                  the goodwill pertaining thereto; (iii) all copyrightable
                  works, all copyrights, and all applications, registrations,
                  and renewals in connection therewith, whether or not
                  registered; (iv) all inventions (whether patentable or
                  unpatentable and whether or not reduced to practice), all
                  improvements thereto, and all patents and pending patent
                  applications together with all reissuances, continuations,
                  continuations-in-part, revisions, extensions, and
                  reexaminations thereof; (v) all trade secrets and confidential
                  business information (including research and development,
                  know-how, formulas, compositions, manufacturing and production
                  processes and techniques, technical data, designs, drawings,
                  specifications, customer and supplier lists, pricing and cost
                  information, and business and marketing plans and proposals);
                  (vi) all proprietary know-how, computer programs and software,
                  and other related items and other data used in and related to
                  the Company's business; (vii) all trademark licenses, royalty
                  agreements, patent licenses and other licenses used in the
                  Company's business; (viii) all technology used in the
                  operation of the Company's business; and (ix) all causes of
                  action for infringement and/or misappropriation of the
                  foregoing, now existing or arising in the future. Set forth on
                  Schedule 3(e)(i) is a list of the Company's patents, patent
                  applications, trademark registrations, trademark applications,
                  copyright registrations, and copyright applications. All such
                  Intellectual Property is valid and enforceable and properly
                  applied for.


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                           (ii)  Except as set forth on Schedule 3(e)(ii), there
                  are no additional patents, patent applications, trademark
                  registrations, trademark applications, copyright registrations
                  or copyright applications owned by or registered in the name
                  of the Company. There are no licensing agreements with respect
                  to any Intellectual Property to which the Company is a party
                  either as a licensor or licensee which currently is used,
                  useful or necessary to operate the Company's business as now
                  being conducted. The operation of the Company's business,
                  including, but not limited to any products to be manufactured
                  and sold by the Company, and the use of the Intellectual
                  Property owned or licensed by the Company do not conflict with
                  or infringe upon third party-owned Intellectual Property.
                  There are no actions, suits, claims, demands, legal or
                  administrative proceedings, or governmental investigations or
                  any actions before any arbitrator, arbitrator panel or other
                  dispute resolution panel that has been served on the Company
                  or, to the best knowledge of the Company, threatened alleging
                  that the technology used in the operation of the Company's
                  business or the use of the Intellectual Property owned or
                  licensed by the Company conflicts with, is a misappropriation
                  of, or infringes upon third-party Intellectual Property. There
                  is no unauthorized use of the Company's Intellectual Property
                  by third-parties.

                           (iii) All present and former employees of and
                  consultants to the Company who have in any way participated in
                  the development of any Intellectual Property of the Company
                  were, at the time such work was performed, bound by written
                  agreements providing for assignment to the Company of all
                  ownership rights in any inventions and copyrightable subject
                  matters resulting from the work ("Invention Agreement"). The
                  forms of Invention Agreement are attached to Schedule
                  3(e)(iii), are enforceable and have not been challenged by any
                  of such employees or consultants.

                           (iv)  All rights, including, but not limited to
                  copyrights, in any and all computer software used by or in any
                  products contemplated to be sold by the Company are owned
                  exclusively by the Company.

                  (f)      Litigation and Investigations. There are no actions,
suits, legal or administrative proceedings or governmental investigations
pending or, to the best knowledge of the Company, threatened against or
affecting or relating to the Shares, the Company, its business or any of its
property or assets, nor any judgments, decrees, orders, rulings, writs or
injunctions specifically referring to the Shares or the Company.

                  (g)      Taxes. All tax returns, including, without
limitation, income, sales, employment and personal property tax returns,
required to be filed by the Company on or prior to the date hereof with the
United States or any state or any other governmental agency or authority have
been duly prepared and filed, and were true and correct and complete. The
Company has withheld and paid all taxes required to have been withheld and paid
in connection with amounts paid or owing to its employees, independent
contractors, creditors and shareholders, except for such taxes which are accrued
for periods after December 31, 2000. All taxes, penalties and interest due by
the Company have been paid. No shareholder, director or officer of the Company
or employee of the Company responsible for tax matters expects any authority to
assess any additional taxes for any period for which tax returns have been filed
or is aware of any basis therefor. There is no dispute or claim concerning any
tax liability of the Company either (i) claimed or raised by any authority in
writing, or (ii) as to which any shareholder, director or officer of the Company
or employee of the Company responsible for tax matters has knowledge based upon
personal contact with any agent of such authority. The Company has not received
any notice of assessment of additional taxes and has not executed or filed with
any taxing authority any agreement extending the period for assessment of any
income or other taxes. The Company has never been audited by any federal, state
or local taxing authority nor is the Company currently the subject of an audit.

                  (h)      Property. The Company does not own any real property.
The Company leases real property located at 3810 Packard Road, Suite 110, Ann
Arbor, Michigan 48108.

                  (i)      Compliance with Laws. The Company's business is being
conducted in compliance with all laws, ordinances and regulations of any
governmental authority applicable to the Company, except where such
non-compliance would not have a material adverse effect on the


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Company. The Company has not received any notice or complaint from any
governmental agency or authority and none is threatened, alleging that the
Company has violated any requirement, law, ordinance or regulation.

         4.       Representations and Warranties of the Purchaser. The Purchaser
represents and warrants to the Company and the Shareholder as follows:

                  (a)      Authorization of the Purchaser. The Purchaser has
full power and authority to execute and deliver this Agreement and to perform
its obligations hereunder. All action on the part of the Purchaser necessary for
the authorization, execution and delivery of this Agreement and for the
performance of all obligations of the Purchaser hereunder has been taken and
this Agreement constitutes valid and legally binding obligations of the
Purchaser, enforceable in accordance with its terms.

                  (b)      Securities Laws Matters. The Purchaser is an
"accredited investor" within the meaning of Securities and Exchange Commission
Rule 501 of Regulation D.

         5.       Closing and Closing Date.

                  (a)      Time and Place. The closing of the purchase and sale
of the Common Stock contemplated herein (the "Closing") shall occur at such
place and time as is mutually agreed to by the parties hereto after the
satisfaction or waiver of all conditions to the obligations of the parties to
consummate the transactions contemplated hereby (which time, date, and place are
referred to in this Agreement as the "Closing Date").

                  (b)      Deliveries and Actions. As part of the Closing, the
Company, the Shareholder and the Purchaser shall make the following deliveries
and taking the following actions:

         (i)      The Company/Shareholder shall deliver to the Purchaser a stock
certificate(s) representing all of the Common Stock being purchased and sold
hereunder duly registered in the name of the Shareholder, endorsed in blank or
with accompanying stock powers duly signed.

                           (ii)   The Shareholder shall deliver to the Purchaser
                  an assignment of all of the Shareholder's rights in the Voting
                  Agreement, dated July 31, 2000 and the Loan Conversion
                  Agreement, dated July 31, 2000, in a form satisfactory to the
                  Purchaser (the "Assignment"). (iii) The Company shall deliver
                  its consent to the Assignment in a form satisfactory to the
                  Purchaser.

                           (iii)  The company shall deliver its consent to the
                  Assignment in a form satisfactory to the Purchaser.

                           (iv)   The Purchaser shall deliver to the Shareholder
                  the aggregate Purchase Price.

         6.       Indemnification.

                  (a)      The Shareholder and the Company agree to indemnify
and hold harmless the Purchaser, and their successors and assigns, against and
with respect to, any and all loss, injury, liability, claim, assessment, damage
or expense (including, without limitation, reasonable attorneys' fees), court
costs and amounts paid in settlement of claims, of any kind or character arising
out of or in any manner incident, relating or attributed to, any inaccuracy in,
or breach or violation of, the representations and warranties made by the
Shareholder or the Company and the covenants and agreements undertaken by them
pursuant to this Agreement, whether or not such inaccuracy or breach or
violation was known to, or should have been known by, any of the parties hereto
on the Closing Date.

                  (b)      The Purchaser agrees to indemnify and hold harmless
the Shareholder and


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the Company, and their successors and assigns, against and with respect to, any
and all loss, injury, liability, claim, assessment, damage or expense
(including, without limitation, reasonable attorneys' fees), court costs and
amounts paid in settlement of claims, of any kind or character arising out of or
in any manner incident, relating or attributed to, any inaccuracy in, or breach
or violation of, the representations and warranties made by the Purchaser and
the covenants and agreements undertaken by them pursuant to this Agreement,
whether or not such inaccuracy or breach or violation was known to, or should
have been known by, any of the parties hereto on the Closing Date.

         7.       Miscellaneous.

                  (a)      Entire Agreement; Amendment. This Agreement
constitutes the entire agreement and understanding of the parties hereto with
respect to the subject matter hereof. No representation, inducement, agreement,
promise or understanding altering, modifying, amending, taking from or adding to
the terms and conditions hereof shall have any force and effect unless the same
is in writing and validly executed by the parties hereto.

                  (b)      Notices. All notices or other communications required
or permitted hereunder shall be in writing and shall be deemed to have been duly
given if physically delivered, telephonically transmitted by telecopier or other
similar means, or three (3) days after having been deposited in the United
States Mail, as certified mail with return receipt requested and with postage
prepaid, addressed to the recipient as follows:

                  If to the Shareholder, to:

                           Stan Cipkowski
                           President
                           American Bio Medica Corporation
                           122 Smith Road
                           Kinderhook, NY  12106

                  If to the Company, to:

                           Gerald Moore
                           BioSys, Inc.
                           3810 Packard Road
                           Suite 110
                           Ann Arbor, MI  48108

                  If to any of the Purchaser, to:

                           Joseph Hollenshead
                           Hollenshead Capital Management LLC
                           9030 West Sahara #410
                           Las Vegas, NV  89117

The addresses and other information so indicated for any party may be changed by
similar written notice.

                  (c)      Parties in Interest. This Agreement shall be binding
upon and inure to the benefit of, and be enforceable by, the parties hereto and
their respective permitted successors and assigns, heirs and personal
representatives.

                  (d)      Assignment. The rights and obligations provided by
this Agreement shall not be assignable by the Purchaser on the one hand and the
Shareholder or the Company on the other hand without the prior written consent
of the Shareholder and the Company or the Purchaser, as the case may be.


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                  (e)      Counterparts. This Agreement may be executed in any
number of counterparts, each of which shall be treated as an original but all of
which, collectively, shall constitute a single instrument.

                  (f)      Severability. In the event that any one or more of
the provisions of this Agreement should be invalid, illegal or unenforceable in
any respect, the validity, legality and enforceability of the remaining
provisions contained herein shall not in any way be affected or impaired
thereby.

                  (g)      Captions. The captions and headings of the sections
and the subsections have been inserted as a matter of convenience and reference
only and shall not control or affect the meaning or construction of this
Agreement.

                  (h)      Governing Law. This Agreement shall be governed by
and construed in accordance with the laws of the State of Ohio without regard to
its rules regarding choice of law.

         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.


PURCHASER:                                  SHAREHOLDER:

HOLLENSHEAD CAPITAL MANAGEMENT              AMERICAN BIO MEDICA CORPORATION
LLC


By: /s/ Joseph Hollenshead                  By: /s/ Stan Cipkowski
   -----------------------------------         ---------------------------------
    Joseph Hollenshead                          Stan Cipkowski



COMPANY:

BIOSYS, INC.


By: /s/ Gerald Moore
   -----------------------------------
    Gerald Moore


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                        EXHIBIT 1 - INTELLECTUAL PROPERTY

THE EDENS REPRESENT THAT THEY ARE THE SOLE OWNERS OF THE ENTIRE RIGHT, TITLE AND
INTEREST IN AND TO THE FOLLOWING:

        -   DEVICE AND METHOD FOR USE IN DETECTING MICROORGANISMS IN A SAMPLE --
            US PATENT 5,366,873.
        -   CONTAINER DEVICE AND METHOD FOR USE IN DETECTING MICROORGANISMS IN
            A SAMPLE -- GB PATENT 2,309,081.
        -   TRANSPARENT VIAL -- DESIGN PATENT APPLICATION 29/089596.
        -   METHOD AND DEVICE FOR CONCENTRATING SELECTED GROUPS OF
            MICROORGANISMS -- PROVISIONAL APPLICATION 60/097,627.
        -   INSTRUMENT FOR DETECTION OF MICROORGANISMS -- PROVISIONAL
            APPLICATION 60/086,503.
        -   KNOW-HOW, AND TRADE SECRETS.
        -   USE OF MICROSYS AND BIOSYS NAMES.



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