<PAGE>

                                                                            4.11

NAME OF SUBSCRIBER:_____________________________________

To:   CARESIDE, INC.
      6100 BRISTOL PARKWAY
      CULVER CITY, CA 90230



                SECURITIES PURCHASE AND SUBSCRIPTION AGREEMENT

                                  SECTION 1.
                                  ----------


          1.1  Subscription.  The undersigned (the "Purchaser"), intending to be
               ------------
legally bound, hereby subscribes for and agrees to purchase the following
securities of Careside, Inc., a Delaware corporation (the "Company"),
immediately upon the acceptance of such subscription by the Company together
with other similar subscriptions which aggregate at least five million dollars
($5,000,000) (the "Minimum Offering"):

               (a)  _____________________ (___________) shares of common stock,
                    $.01 par value per share (the "Common Stock"), and

               (b)  a contingent warrant (the "Contingent Warrant") to purchase
                    an additional __________ (_________) shares of Common Stock
                    for a purchase price of $.01 per share of Common Stock, such
                    warrant to be in the form of Exhibit A hereto,

for an aggregate purchase price of ______________ dollars ($___________) (the
"Aggregate Purchase Price") in accordance with the terms and conditions of this
Securities Purchase and Subscription Agreement (the "Subscription Agreement")
and pursuant to the Company's Confidential Private Offering Memorandum dated
February 2, 2000 (the "Confidential Memorandum").

          1.2  Purchase of Securities; Delivery of Documents. The Purchaser
               ---------------------------------------------
understands and acknowledges that the Aggregate Purchase Price shall be remitted
to H.C. Wainwright & Co., Inc. (the "Placement Agent"), as agent for the
Company, in exchange for the Common Stock and Contingent Warrant (the "Purchased
Securities").  Payment for the Purchased Securities shall be made by certified
check or wire transfer in accordance with the instructions of the Placement
Agent, together with an executed copy of this Subscription Agreement.  Also,
contemporaneously with the execution and delivery of this Subscription Agreement
by the Purchaser, the Purchaser is delivering to the Company a completed
Accredited Investor Questionnaire (the "Questionnaire") in the form attached to
the Confidential Memorandum as Exhibit C.
                               ---------
<PAGE>

          1.3  Pricing of Purchased Securities.  The Aggregate Purchase Price is
               -------------------------------
equal to the number of shares of Common Stock which are the subject of this
Subscription Agreement multiplied by $8.77, which is eighty percent (80%) of the
average closing trading price, as quoted by the American Stock Exchange
("AMEX"), for Common Stock for the twenty (20) trading days immediately
preceding the date of this Agreement.

                                  SECTION 2.
                                  ----------

          2.1  Acceptance or Rejection. The Company's acceptance of the
               -----------------------
Purchaser's subscription shall be evidenced by the Company's execution and
delivery of a duplicate original or a copy of this Subscription Agreement to the
Purchaser.

          (a)  The Purchaser understands and agrees that the Company reserves
the right to reject this subscription for the Common Stock in whole or in part,
at any time prior to the applicable Closing (as defined in Section 2.2 hereof),
notwithstanding prior receipt by the Purchaser of notice of acceptance of the
Purchaser's subscription.

         (b)   In the event a subscription is accepted in part, the applicable
portion of the Aggregate Purchase Price shall be retained by the Company in
payment of the shares of Common Stock to be sold to the Purchaser and the
balance shall be returned promptly to the Purchaser, without interest thereon.

         (c)   The Purchaser understands and agrees that this offer to purchase
is and shall be irrevocable, but its obligations hereunder will terminate if
this offer is rejected by the Company, pursuant to the terms herein.

         (d)   In the event of rejection of this subscription, or in the event
the sale of the Common Stock subscribed for by the Purchaser is not consummated
by the Company for any reason (in which event this Subscription Agreement shall
be deemed to be rejected), this Subscription Agreement and any other agreement
entered into between the Purchaser and the Company relating to this subscription
shall thereafter have no force or effect and the Company shall promptly return
or cause to be returned to the Purchaser the Aggregate Purchase Price remitted
to the Company by the Purchaser, without interest thereon or deduction
therefrom.

         (e)   Pending acceptance or rejection of this subscription at a
Closing, the Aggregate Purchase Price shall be held in escrow by American Stock
Transfer & Trust Company (the "Escrow Agent") pursuant to an escrow agreement
among the Company, the Placement Agent and the Escrow Agent.

          2.2  Closing; Closing Date.
               ---------------------

          The closing of the purchase and sale of the Minimum Offering (the
"Initial Closing") shall take place at the offices of Pepper Hamilton LLP, 3000
Two Logan Square, Philadelphia, PA  19103, or such other place as may be
mutually agreed by the Company and the

                                      -2-
<PAGE>

Placement Agent, no later than March 8, 2000 (the "Termination Date") or upon
the Company's acceptance of subscriptions equal to the Minimum Offering.
Subsequent closings of part or all of the sale of securities contemplated by the
Confidential Memorandum, if any, will be held at such times after the Initial
Closing as shall be determined by the Company (each, a "Closing") prior to the
Termination Date. At the Initial Closing, the Company shall deliver to the
Purchaser (i) certificates for the Common Stock and Contingent Warrants issued
and sold to the Purchaser, duly registered in the Purchaser's name (or their
nominee) against payment in full by the Purchaser of the Aggregate Purchase
Price, and (ii) an opinion of Pepper Hamilton LLP, counsel to the Company,
addressed to the Purchaser with respect to the valid existence and good standing
of the Company, the due authorization, execution and delivery of this Agreement
and the issuance and sale of the Common Stock and Contingent Warrants , and that
the Common Stock and Contingent Warrants, upon issuance and sale to the
Purchaser, are duly authorized, validly issued, fully paid and nonassessable.

                                  SECTION 3.
                                  ----------

          3.1  Representations and Warranties of the Company.
               ---------------------------------------------

          The Company represents and warrants that:

          (a)  The Company is a corporation duly organized and validly existing
and in good standing under the laws of the State of Delaware, and duly qualified
to do business and in good standing as a foreign corporation in each state in
which the nature of its business or properties requires such qualification
(except where failure to qualify would not have a material adverse effect on the
Company taken as a whole), with full power and authority, corporate and
otherwise, to enter into and perform this Subscription Agreement, and to execute
and deliver the various instruments and documents provided for herein.

          (b)  The execution, delivery and performance by the Company of this
Subscription Agreement and the issuance and delivery by the Company of the
Common Stock and Contingent Warrant as contemplated hereby have been duly
authorized by all necessary corporate action and will not violate any provision
of law, court order or decree, or any provision of the Company's Certificate of
Incorporation or Bylaws, or result in the breach of, constitute a default under
or result in the creation of any lien, charge or encumbrance upon any property
or assets of the Company pursuant to any agreement or instrument to which the
Company is a party, or by which it or any of its property may be bound or
affected.  This Subscription Agreement is a valid and binding obligation of the
Company, enforceable in accordance with its terms subject to general principles
of equity and bankruptcy and other laws affecting creditors' rights generally.

          (c)  There are no material lawsuits or proceedings pending, or, to the
Company's knowledge, threatened, against or affecting the Company and there are
no proceedings before any governmental commission, bureau or other
administrative agency pending, or, to the Company's knowledge, threatened,
against or affecting the Company.

                                      -3-
<PAGE>

          (d)  As of January 31, 2000, the authorized capital stock of the
Company consisted of 50,000,000 shares of common stock, $.01 par value per share
(the Company "Common Stock") and 5,000,000 shares of preferred stock, $.01 par
value per share (the "Preferred Stock"). As of January 31, 2000, there were
7,609,581 shares of Company Common Stock and 162,914 shares of Series A
Preferred Stock (the "Series A Preferred Stock") outstanding. As of January 31,
2000, 4,272,444 shares of Company Common Stock are issuable upon the exercise of
currently exercisable warrants and options and upon the conversion of the
outstanding shares of Series A Preferred Stock.

         (e)  The Common Stock issuable under this Subscription Agreement or
upon exercise of the Contingent Warrant has been duly authorized and, when
issued against payment therefor, will be validly issued, fully paid and
nonassessable and will be issued in reliance upon applicable exemptions from the
registration and qualification provisions of all applicable securities laws of
the United States and each state whose securities laws may be applicable
thereto.  All Common Stock purchased hereunder or upon exercise of the
Contingent Warrant will be issued free and clear of any preemptive or similar
right and free and clear of any claim, lien, security interest or other
encumbrance.  The Company has reserved for issuance upon exercise of the
Contingent Warrant the full number of shares of Common Stock issuable upon
exercise thereof.

          (f)  No governmental permit, consent, approval or authorization is
required in connection with (i) the execution, delivery and performance of this
Subscription Agreement by the Company or (ii) the offer, sale, issuance and
delivery by the Company of the Common Stock and Contingent Warrant contemplated
hereby; provided that, all representations made to the Company by the Purchaser
        -------------
in this Subscription Agreement and in any other document or instrument delivered
in connection herewith are assumed for purposes of this representation and
warranty to be accurate and complete.

          (g)  Each of the Company's reports or filings with the Securities and
Exchange Commission ("SEC") that have been incorporated by reference into the
Confidential Memorandum complied as to form, at the time of filing of such
reports or filings, in all material respects with the requirements of the
Securities Exchange Act of 1934, as amended (the "Exchange Act") and the rules
and regulations promulgated under such Act.

          (h)  The Confidential Memorandum and any amendment or supplement
thereto provided by the Company to the Purchaser does not, at the date hereof,
contain any untrue statement of a material fact or omit to state a material fact
required to be stated therein or necessary to make the statements therein not
misleading.

          (i)  As of the date hereof, the Company's Common Stock and its
publicly traded warrants are traded on the AMEX. Within thirty (30) days after
the Initial Closing, the Company shall file a registration statement to register
such number of shares of Common Stock issued or issuable in connection with the
offering contemplated by the Confidential Memorandum (the "Offering") in the
manner set forth in Section 5.1 below.

                                      -4-
<PAGE>

          (j)  No sale of Common Stock or other securities by the Company within
the last six (6) months require integration under the Act and Regulation D
promulgated thereunder or would materially adversely affect the sale of the
Common Stock and Contingent Warrants or the timely effectiveness of the
Registration Statement referred to in Appendix II.

                                  SECTION 4.
                                  ----------

          4.1  Purchaser Representations and Warranties.
               ----------------------------------------

          The Purchaser hereby acknowledges, represents and warrants to, and
agrees with, the Company and its affiliates as follows:

          (a)  The Purchaser has received, read carefully and understands the
Confidential Memorandum and has had an adequate opportunity to consult his own
attorney, accountant or investment advisor (his "Advisors") with respect to the
suitability of the investment contemplated hereby for the Purchaser.  The
Purchaser further acknowledges that the Purchaser and his Advisors have also
made such other investigation, review, examination and inquiry concerning the
Company and its business and affairs as they have deemed appropriate so as to
understand the nature of the investment in the Purchased Securities, including
without limitation, the merits and risks thereof.

          (b)  The Purchaser is acquiring the Purchased Securities for the
Purchaser's own account as principal, not as a nominee or agent, for investment
purposes only, and not with a view to, or for, resale, distribution or
fractionalization thereof in whole or in part, which resale, distribution or
fractionalization would violate the Securities Act of 1933, as amended (the
"Securities Act").  Further, the Purchaser does not have any contract,
undertaking, agreement or arrangement with any person to sell, transfer or grant
participations to such person or to any third person, with respect to the
Purchased Securities, for which the Purchaser is subscribing.

          (c)  The Purchaser has full power and authority to enter into this
Subscription Agreement. The execution and delivery of this Subscription
Agreement has been duly authorized, if applicable, by the Purchaser and this
Subscription Agreement constitutes a valid and legally binding obligation of the
Purchaser.

          (d)  The Purchaser acknowledges the Purchaser's understanding that the
offering and sale of the Purchased Securities is intended to be exempt from
registration under the Securities Act by virtue of Section 4(2) thereof and the
provisions of Regulation D promulgated thereunder ("Regulation D").  In
furtherance thereof, the Purchaser represents and warrants to and agrees with
the Company and its affiliates as follows:

               (i) The Purchaser understands that the basis for the exemption
          from registration may not be present if, notwithstanding such
          representations, the Purchaser's intention is merely to acquire the
          Common Stock for a fixed or determinable period in the future, or for
          a market rise, or for sale if the market does not rise.  Accordingly,
          the Purchaser does not have any such intention;

                                      -5-
<PAGE>

               (ii)  The Purchaser has the financial ability to bear the
          economic risk of the Purchaser's investment, has adequate means for
          providing for the Purchaser's current needs and personal contingencies
          and has no need for liquidity with respect to the Purchaser's
          investment in the Company; and

               (iii) The Purchaser has such knowledge and experience in
          financial and business matters as to be capable of evaluating the
          merits and risks of the prospective investment in the Common Stock.
          If other than an individual, the Purchaser also represents that it has
          not been organized for the purpose of acquiring the Common Stock.

          (e)  The information in the Questionnaire completed and executed by
the Purchaser is accurate and true in all respects and the Purchaser is an
"accredited investor," as that term is defined in Rule 501 of Regulation D as
described in Appendix I hereto.
             ----------

          (f)  The Purchaser:

               (i)   Has been furnished with copies of the Confidential
          Memorandum, a List of FDA Approved Tests, the Company's Quarterly
          Report on Form 10-Q for the quarter ended September 30, 1999, certain
          audited and unaudited financial statements and any documents which may
          have been made available upon request for a reasonable period of time
          prior to the date hereof (collectively, the "Documents").  The
          Purchaser acknowledges and agrees that the Documents supercede all
          written information regarding the Company that the Purchaser may have
          received prior to the date of the Documents.  The Purchaser has
          carefully read the Documents and has relied solely (except as
          indicated in subsections (ii) and (iii) below) on the information
          contained in the Documents (including all exhibits thereto);

               (ii)  Has been provided an opportunity for a reasonable period of
          time prior to the date hereof to obtain additional information
          concerning the Purchased Securities, the Company and all other
          information to the extent the Company possesses such information or
          can acquire it without unreasonable effort or expense;

               (iii) Has been given the opportunity for a reasonable period of
          time prior to the date hereof to ask questions of, and receive answers
          from, the Company or its representatives concerning the terms and
          conditions of the Offering and other matters pertaining to this
          investment, and has been given the opportunity for a reasonable period
          of time prior to the date hereof to obtain such additional information
          necessary to verify the accuracy of the information contained in the
          Documents or that which was otherwise provided in order for the
          Purchaser to evaluate the merits and risks of purchase of the
          Purchased Securities

                                      -6-
<PAGE>

          to the extent the Company possesses such information or can acquire it
          without unreasonable effort or expense;

               (iv) Has not been furnished with any oral representation or oral
          information in connection with the Offering which is not contained
          herein or in the Documents; and

               (v)  Has determined that the Purchased Securities are a suitable
          investment for the Purchaser and that at this time the Purchaser could
          bear a complete loss of such investment.

          (g)  This offer is not transferable or assignable by the Purchaser
unless the Purchaser complies with the terms of transfer hereof.  The Purchaser
further represents, warrants and agrees that the Purchaser will not sell or
otherwise transfer the Purchased Securities, without registration under the
Securities Act or an exemption therefrom, and that the Purchaser fully
understands and agrees that the Purchaser must bear the economic risk of the
Purchaser's purchase because, among other reasons, none of the Purchased
Securities has been registered under the Securities Act or under the securities
laws of any state and, therefore, none can be resold, pledged, assigned or
otherwise disposed of unless they are subsequently registered under the
Securities Act and under the applicable securities laws of such states or an
exemption from such registration is available.  In particular, the Purchaser is
aware that the Common Stock is a "restricted security," as such term is defined
in Rule 144 promulgated under the Securities Act ("Rule 144"), and may not be
sold pursuant to Rule 144 unless all of the conditions of Rule 144 are met.  The
Purchaser also understands that, except as expressly otherwise provided herein,
the Company is under no obligation to register the Common Stock on the
Purchaser's behalf or to assist the Purchaser in complying with any exemption
from registration under the Securities Act or applicable state securities laws.
The Purchaser further understands that sales or transfers of the Purchased
Securities are further restricted by state securities laws and the provisions of
this Subscription Agreement.

          (h)  No representations or warranties have been made to the Purchaser
by the Company, or any officer, employee, agent or affiliate of the Company,
other than the representations and warranties of the Company contained herein,
and in subscribing for the Purchased Securities, the Purchaser is not relying
upon any representations other than those contained herein.

          (i)  Any information which the Purchaser has heretofore furnished to
the Company with respect to the Purchaser's financial position and business
experience is correct and complete as of the date of this Subscription Agreement
and if there should be any material change in such information the Purchaser
will immediately furnish such revised or corrected information to the Company.

          (j)  The Purchaser understands and agrees that, at issuance, the
Common Stock shall bear the following legend, or a similar legend to the same
effect, until (i) such Common Stock shall have been registered under the
Securities Act and effectively been disposed

                                      -7-
<PAGE>

of in accordance with a registration statement that has been declared effective;
or (ii) in the opinion of counsel for the Company such Common Stock be may sold
without registration under the Securities Act or any applicable "Blue Sky" or
state securities laws:

     "THE COMMON STOCK REPRESENTED BY THIS CERTIFICATE HAS NOT BEEN
     REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
     "ACT"), AND IS SUBJECT TO RESTRICTIONS ON TRANSFERABILITY AS SET
     FORTH IN THIS CERTIFICATE. THE COMMON STOCK REPRESENTED HEREBY
     MAY NOT BE SOLD, TRANSFERRED, OR OTHERWISE DISPOSED OF IN THE
     ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT UNDER THE ACT OR
     AN OPINION OF COUNSEL, REASONABLY ACCEPTABLE TO COUNSEL FOR THE
     COMPANY, TO THE EFFECT THAT THE PROPOSED SALE, TRANSFER, OR
     DISPOSITION MAY BE EFFECTUATED WITHOUT REGISTRATION UNDER THE
     ACT."

          (k)  The Purchaser is not (i) a director, officer, or substantial
security holder of the Company (a "Related Party"), (ii) a subsidiary, affiliate
or other closely-related person of a Related Party, or (iii) any person, company
or entity in which a Related Party has a substantial direct or indirect
interest.

          (l)  No Federal or state agency has made any findings or determination
as to the fairness of the Offering or the Purchased Securities (or any part
thereof) for investment, or any recommendation or endorsement of any of the
Purchased Securities (or any part thereof).

          (m)  The Purchaser covenants that it will not, directly or indirectly
through its affiliates or agents, at any time prior to December 15, 2000, effect
shorts sales of the Common Stock or hedge transactions in the Common Stock that
customarily result in a counter party engaging in short sales.

          (n)  The foregoing representations, warranties and agreements shall
survive the Closing.


                                      -8-
<PAGE>

                                  SECTION 5.
                                  ----------

          5.1  Registration of the Common Stock.  Within thirty (30) days after
               --------------------------------
the Initial Closing, the Company shall file a registration statement on Form S-1
registering for resale the Common Stock included in the Purchased Securities and
the shares of Common Stock issuable upon exercise of the Contingent Warrant in
accordance with the provisions set forth in Appendix II, which is attached
                                            -----------
hereto and incorporated by reference as if set forth herein in its entirety. The
Company shall use its reasonable best efforts to have such registration
statement declared effective and to cause the listing of the Common Stock on the
AMEX as soon as practicable.  The Company does not hereby undertake to register
the Contingent Warrant included in the Purchased Securities.

                                  SECTION 6.
                                  ----------

          6.1  Indemnification of the Company.
               -------------------------------

          (a)  The Purchaser agrees to indemnify and hold harmless the Company,
its officers and directors, employees, agents and affiliates and each other
person, if any, who controls any thereof within the meaning of Section 15 of the
Securities Act or Section 20(a) of the Exchange Act, against any loss,
liability, claim, damage and expense whatsoever (including, but not limited to,
any and all expenses whatsoever reasonably incurred in investigating, preparing
or defending against any litigation commenced or threatened or any claim
whatsoever) arising out of or based upon any false representation or warranty or
breach or failure by the Purchaser to comply with any covenant or agreement made
by the Purchaser herein or in any other document furnished by the Purchaser to
any of the foregoing in connection with this transaction.  The Purchaser also
agrees to indemnify the Company as set forth in Appendix II with respect to the
                                                -----------
resale registration of Common Stock included or underlying the Purchased
Securities.

          6.2  Indemnification of Purchaser. The Company agrees to indemnify and
               ----------------------------
hold harmless the Purchaser against any loss, liability, claim, damage and
expense whatsoever (including, but not limited to, any and all expenses
whatsoever reasonably incurred in investigating, preparing or defending against
any litigation commenced or threatened or any claim whatsoever) arising out of
or based upon any false representation or warranty or breach or failure by the
Company to comply with any covenant or agreement made by the Company herein or
in any other Document furnished by the Company to any of the foregoing in
connection with the transaction contemplated by this Subscription Agreement. The
Company also agrees to indemnify the Purchaser as set forth in Appendix II with
                                                               -----------
respect to the resale registration of the Common Stock included in or underlying
the Purchased Securities.

          6.3  Modification.  Neither this Subscription Agreement nor any
               ------------
provisions hereof shall be modified, discharged or terminated except by an
instrument in writing signed by the party against whom any waiver, change,
discharge or termination is sought.

                                      -9-
<PAGE>

          6.4  Notices.  All notices, authorizations, demands or requests
               -------
required or permitted to be delivered to any party in connection with this
Subscription Agreement shall be in writing and shall be deemed to have been duly
given if personally delivered, if sent by facsimile transmission (with receipt
confirmed by automatic transmission report), if sent by a nationally-recognized
overnight courier with charges prepaid, if sent by registered or certified mail,
return receipt requested and postage prepaid (or by the most nearly comparable
method if mailed from or to a location outside the United States), or addressed
as follows:

          If to the Company, to:

               6100 Bristol Parkway
               Culver City, CA 90230
               Attn:  James R. Koch
               Fax: 310-338-6789

               With copies (which copies shall not constitute notice) to:

               Pepper Hamilton LLP
               3000 Two Logan Square
               Philadelphia, PA 19103-2799
               Attn: Julia D. Corelli, Esquire
               Fax: 215-981-4750

          If to the Purchaser, to the address shown on such Purchaser's
signature page hereto.

or to such other address as the party to whom the notice is to be given may have
furnished to the other party hereto in writing in accordance with the provisions
of this Section 6.4.  Any such notice or communication shall be deemed to have
been received (i) in the case of personal delivery, on the date of such
delivery, (ii) in the case of facsimile transmission (with receipt confirmed by
automatic transmission report), on the date of such transmission, (iii) in the
case of a nationally-recognized overnight courier, on the next business day
after the date when delivered to such courier, and (iv) in the case of mailing
(or by the most nearly comparable method if mailed from or to a location outside
the United States), on the third business day following that on which the piece
of mail containing such communication is posted; provided, however, that three
                                                 --------  -------
additional business days shall be added to the time any notice or communication
sent from or to a location outside the United States shall be deemed to have
been received in (iii) or (iv) above.

          6.5  Counterparts. This Subscription Agreement may be executed through
               ------------
the use of separate signature pages or in any number of counterparts (and by
facsimile signature), and each of such counterparts shall, for all purposes,
constitute one agreement binding on all parties, notwithstanding that all
parties are not signatories to the same counterpart.

                                      -10-
<PAGE>

          6.6  Binding Effect.  Except as otherwise provided herein, this
               --------------
Subscription Agreement shall be binding upon and inure to the benefit of the
parties and their heirs, executors, administrators, successors, legal
representatives and assigns.  If the Purchaser is more than one person, the
obligation of the Purchaser shall be joint and several and the agreements,
representations, warranties and acknowledgments herein contained shall be deemed
to be made by and be binding upon each such person and his heirs, executors,
administrators and successors.

          6.7  Severability.  In the event that any provision of this
               ------------
Subscription Agreement shall be deemed to be invalid, illegal or unenforceable,
the validity, legality or enforceability of the remaining provisions shall not
in any way be affected or impaired thereby.

          6.8  Entire Agreement.  This Subscription Agreement and the documents
               ----------------
referenced herein contain the entire agreement of the parties and there are no
representations, covenants or other agreements except as stated or referred to
herein and therein.

          6.9  Assignability.  This Subscription Agreement is not transferable
               -------------
or assignable by the Purchaser.

          6.10 Applicable Law.  This Subscription Agreement shall be governed by
               --------------
and construed in accordance with the laws of the State of Delaware, without
giving effect to conflicts of law principles.

          6.11 Jurisdiction.  The Purchaser and the Company each hereby submit
               ------------
to the exclusive jurisdiction of the courts of the State of Delaware and to the
United States District Court for the District of Delaware with respect to any
action or legal proceeding commenced by either of them with respect to this
Subscription Agreement, the Offering or the Common Stock.  Each of them
irrevocably waives any objection they now have or hereafter may have respecting
the venue of any such action or proceeding brought in such a court or respecting
the fact that such court is an inconvenient forum and consents to the service of
process in any such action or proceeding by means of registered or certified
mail, return receipt requested, in care of the address set forth above or below
or at such other address as either of them shall furnish in writing to the
other.

          6.12 Waiver.  The Purchaser and the Company each hereby waive trial by
               ------
jury in any action or proceeding involving any matter (whether sounding in tort,
contract, fraud or otherwise) in any way arising out of or relating to this
Subscription Agreement, the Offering or the Common Stock.

          6.13 Pronouns.  The use herein of the masculine pronouns "he," "him"
               --------
or "his" or similar terms shall be deemed to include the feminine and neuter
genders as well and the use herein of the singular pronoun shall be deemed to
include the plural as well.

          6.14 Survival.  The respective indemnities, representations,
               --------
warranties and agreements of the Company and the Purchasers contained in this
Subscription Agreement or made by or on behalf on them, respectively, pursuant
to this Subscription Agreement, shall survive the delivery of and payment for
the Common Stock and shall remain in full force and

                                      -11-
<PAGE>

effect regardless of any investigation made by or on behalf of any of them or
any person controlling any of them for a period of one year from the date
hereof.

                                      -12-
<PAGE>

                         EXECUTION PAGE FOR INDIVIDUAL

     IN WITNESS WHEREOF, subject to acceptance by the Company, the undersigned
has completed this Subscription Agreement to evidence its offer to purchase the
Purchased Securities, comprised of Common Stock and the Contingent Warrant, on
this _________ day of ______________,2000.

Number of Shares of Common Stock subscribed for:                 ______________.
Amount of check enclosed:                                        $_____________.


______________________________________   ______________________________________
Signature of Purchaser                   (Name of Purchaser - Please Print)

______________________________________   ______________________________________
Social Security Number of Purchaser      Address of Purchaser

Accepted:

Dated: _________________, 2000           CARESIDE, INC.

                                         By:___________________________________
                                         Name:
                                         Title:

                                      14
<PAGE>

               EXECUTION PAGE FOR OFFER TO PURCHASE BY AN ENTITY
                   (Not applicable to offers by individuals)

     IN WITNESS WHEREOF, subject to acceptance by the Company, the undersigned
has completed this Subscription Agreement to evidence its offer to purchase the
Purchased Securities, comprised of Common Stock and the Contingent Warrant, this
___ day of ______________, 2000.

Number of Shares of Common Stock subscribed for:            _____________.

Amount of check enclosed:                                         $__________.


__ TRUST        -  (Please include copy of trust agreement)
__ CORPORATION  -  (Attach certified corporate resolution authorizing signature
                   and a copy of the articles of incorporation)
__ PARTNERSHIP  -  (Attached copy of the partnership agreement)

(Please print the following information exactly as you wish it to appear on the
Company records.)

_____________________________           ______________________________________
(Name of Subscriber)                    (Address)

_____________________________           ______________________________________
(Tax Identification Number)

_____________________________           ______________________________________
(Telephone)

     The undersigned trustee, partner or corporate officer certifies that he has
full power and authority from the beneficiaries, partners or directors of the
entity named below to execute this Subscription Agreement on behalf of the
entity and to make the representations and warranties made herein on their
behalf and that investment in the Company has been affirmatively authorized by
the governing board of such entity and is not prohibited by the governing
documents of the entity.

Date: ______________, 2000              ________________________________________
                                        (Print Name of Entity)

_____________________________           By:_____________________________________
(Print Name and Capacity)               (Signature of authorized trustee,
                                        partner, or corporate officer)


ACCEPTED:

Date: ______________, 2000              CARESIDE, INC.


                                        By:_____________________________________
                                        Name:
                                        Title:

                                      15
<PAGE>

                           CORPORATE ACKNOWLEDGMENT


STATE OF            )
                    )ss.:
COUNTY OF           )


     On this ___ day of ____________, 2000, before me personally came
_________________ to be known, being by me duly sworn, did depose and say that
he resides at ___________________________________, that he is the
________________________ of ________________________________, the corporation
described in and which executed the foregoing instrument; that he knows the seal
of said corporation; that the seal affixed to said instrument is such corporate
seal; that it was so affixed by order of the board of directors of said
corporation, and that he signed his name thereto by like order.


                                                ____________________________
                                                        Notary Public



PARTNERSHIP ACKNOWLEDGMENT


STATE OF            )
                    )ss.:
COUNTY OF           )


     On this ___ day of ____________, 2000, before me personally came
_________________ to be known, to be a partner in
___________________________________, a partnership, and known to be the person
described in and who executed the foregoing instrument in the partnership name,
and said ____________ duly acknowledged that he executed the foregoing
instrument on behalf of said partnership.


                                                ____________________________
                                                        Notary Public

                                      16
<PAGE>

                                  Appendix I
                                  ----------

     Pursuant to Rule 501 of Regulation D promulgated under the Securities Act,
an accredited investor means:

     (a)  A bank as defined in Section 3(a)(2) of the Securities Act, or any
          savings and loan association or other institution as defined in
          Section 3(a)(5)(A) of the Securities Act whether acting in its
          individual or fiduciary capacity; any broker or dealer registered
          pursuant to Section 15 of the Securities Exchange Act of 1934; any
          insurance company as defined in Section 2(13) of the Securities Act,
          any investment company registered under the Investment Company Act of
          1940 or a business development company as defined in Section 2(a)(48)
          of that act; any Small Business Investment Company licensed by the
          U.S. Small Business Administration under Section 301(c) or (d) of the
          Small Business Investment Act of 1958; any plan established and
          maintained by a state, its political subdivisions, or any agency or
          instrumentality of a state or its political subdivisions, for the
          benefit of its employees if such plan has total assets in excess of
          $5,000,000; any employee benefit plan within the meaning of the
          Employee Retirement Income Security Act of 1974 if the investment
          decision is made by a plan fiduciary, as defined in Section 3(21) of
          such act, which is either a bank, savings and loan association,
          insurance company, or registered investment advisor, or if the
          employee benefit plan has total assets in excess of $5,000,000 or, if
          a self-directed plan, with investment decision made solely by persons
          that are accredited investors;

     (b)  Any private business development company as defined in Section 202
          (a)(22) of the Investment Advisers Act of 1940;

     (c)  Any organization described in Section 501(c)(3) of the Internal
          Revenue Code (the "Code"), corporation, Massachusetts or similar
          business trust, or partnership, not formed for the specific purpose of
          acquiring the securities offered, with total assets in excess of
          $5,000,000;

     (d)  Any director or executive officer of the Company;

     (e)  Any natural person whose individual net worth, or joint net worth with
          that person's spouse, at the time of such person's purchase exceeds
          $1,000,000;

     (f)  Any natural person who had an individual income in excess of $200,000
          in each of the two most recent years or joint income with that
          person's spouse in excess of $300,000 in each of those years and who
          reasonably expects to reach the same income level in the current year;

     (g)  Any trust, with assets in excess of $5,000,000, not formed for the
          specific purpose of acquiring the securities offered, whose purchase
          is directed by a person having such knowledge and experience in
          financial and business matters so such person is capable

                                      17
<PAGE>

          of evaluating the merits and risks of the investment to be made; or

     (h)  Any entity in which all of the equity owners are accredited investors.

     In addition, a participant in a defined contribution or profit sharing plan
qualified under Section 401 of the Code may be deemed the purchaser of the
Common Stock for the purpose of determining whether the plan is an accredited
investor if the following conditions are satisfied: (x) the plan trust must
provide for segregated accounts for each plan participant, (y) the plan document
must provide the participant with the power to direct the trustee to make each
particular investment to the extent of the participant's voluntary contributions
plus that portion of employer contributions that have vested to the
participant's benefit and (z) the investment in the Common Stock must have been
made pursuant to an exercise by the participant of the power to direct the
investment of his or her account in the plan trust.

                                      18
<PAGE>

                                  Appendix II
                                  -----------


     1.  Registration of the Common Stock.
         --------------------------------

         (a) Subject to paragraph 1(b) below, within thirty (30) days after the
Initial Closing, the Company agrees to file a registration statement (the
"Registration Statement") on Form S-1 with the Securities Exchange Commission
("Commission") registering the Common Stock (which term, for all purposes of
this Appendix II, shall be deemed to include the shares of Common Stock issuable
upon exercise of the Contingent Warrant) for sale under the Securities Act. The
Company reserves the right to convert such registration to a registration with
like effect on any other form that may be or may become available to the
Company.  The Company further reserves the right to include in such registration
statement for registration any shares of its Common Stock which the Company, in
its sole discretion, determines to include therein.

         (b) If the Company shall furnish to the holders of Common Stock
included in the Registration Statement (each a "Holder", and collectively the
"Holders") a certificate signed by its Chief Executive Officer stating that, in
the good faith judgment of the Company's Board of Directors, it would be
detrimental to the Company and its shareholders for the Registration Statement
to be filed by reason of a material activity or pending event or transaction
(such as a material acquisition, joint venture, merger, consolidation or
financing transaction) and it is therefore advisable to defer the filing of such
registration statement, the Company shall have a one-time right to defer such
filing of the Registration Statement for a period of not more than ninety (90)
days after the date upon which the Company would otherwise have been required to
file the Registration Statement pursuant to Section 1(a). The Company hereby
confirms that it is not aware of any event, development, fact or state of
affairs that exists as of the date hereof that constitutes, or that would
reasonably be expected to lead to, a material activity or pending event or
transaction within the meaning of the preceding sentence.

         (c) The Company's obligation to register is limited to one Registration
Statement which becomes effective under the Securities Act, and, provided that
the Company complies with its obligations under this Agreement, no further
registration statements (other than required amendments or supplements to the
original Registration Statement) will be filed for the benefit of the Holders.

         (d) The Company shall use its best efforts to obtain effectiveness of
the Registration Statement as soon as practicable and shall continue to use its
best efforts to maintain such effectiveness for the registration until the
earlier of (i) the second (2nd) anniversary of the Initial Closing or (ii) the
date on which the Holder or his permitted transferee or assignee no longer holds
any Common Stock. The Registration Statement filed in connection herewith shall
not be deemed to have been effected unless it has become effective with the
Commission. Notwithstanding the foregoing, the Registration Statement will not
be deemed to have been effected if after it has become effective under the
Securities Act, such registration is interfered with by any stop order,
injunction or other order or requirement of the Commission or other

                                      19
<PAGE>

governmental agency or any court proceeding for any reason. The Company shall
use its best efforts to prevent the issuance of any stop order or other
suspension of effectiveness of the Registration Statement, and, if such an order
is issued, to obtain the withdrawal of such order at the earliest possible
moment and to notify the Purchaser of the issuance of such order and the
resolution thereof.

     2.   Registration Expenses. The Company shall pay all expenses incurred in
          ---------------------
connection with the registration of the Common Stock on the Registration
Statement.

     3.   Registration Procedures.
          -----------------------

          a.   In connection with the Company's obligation to register the
Common Stock under the Securities Act as provided in Section 1, the Company, as
expeditiously as possible and subject to the terms and conditions herein, will
use its best efforts to:

               (i)   cause the Registration Statement to be prepared and filed
          with the Commission pursuant to Section 1(a) above to become effective
          as soon as practicable;

               (ii)  prepare and file with the Commission such amendments and
          supplements to such Registration Statement and the prospectus used in
          connection therewith as may be necessary to keep such Registration
          Statement effective and to comply with the provisions of the
          Securities Act with respect to the disposition of all securities
          covered by such Registration Statement until such time as no Holder or
          his permitted transferee or assignee holds any Common Stock or, if
          earlier, the second (2/nd/) anniversary of the Initial Closing;

               (iii) furnish to the Holders such number of conformed copies of
          such registration statement and of each such amendment and supplement
          thereto (in each case including all exhibits), such number of copies
          of the prospectus contained in such Registration Statement (including
          each preliminary prospectus and any summary prospectus) and any other
          prospectus filed under the Securities Act, in conformity with the
          requirements of the Securities Act, and such other documents, in each
          case, as the Holders may reasonably request;

               (iv)  register or qualify all Common Stock covered by such
          Registration Statement under such other United States state securities
          or blue sky laws of such jurisdictions as any of the Holders shall
          reasonably request, to keep such registration or qualification in
          effect for so long as such registration remains in effect, and take
          any other action which may be reasonably necessary or advisable to
          enable the Holders to consummate the disposition of the Common Stock
          owned by the Holders in such jurisdictions, except that the Company
          shall not for any such purpose be required to qualify generally to do
          business as a foreign corporation in any jurisdiction wherein it would
          not but for the requirements of

                                      20
<PAGE>

          this Section 3(a)(iv) be obligated to be so qualified, subject itself
          to taxation in any such jurisdiction, or consent to general service of
          process in any such jurisdiction;

               (v)    immediately notify the Holders at any time when a
          prospectus relating to the Common Stock is required to be delivered
          under the Securities Act, of the happening of any event as a result of
          which the prospectus included in such Registration Statement, as then
          in effect, includes an untrue statement of a material fact or omits to
          state any material fact required to be stated therein or necessary to
          make the statements therein not misleading in the light of the
          circumstances under which they were made, and promptly prepare and
          furnish to the Holders a reasonable number of copies of a supplement
          to or an amendment of such prospectus as may be necessary so that, as
          thereafter delivered to the purchasers of such Common Stock, such
          prospectus shall not include an untrue statement of a material fact or
          omit to state a material fact required to be stated therein or
          necessary to make the statements therein not misleading in the light
          of the circumstances under which they were made;

               (vi)   comply with all applicable rules and regulations of the
          Commission, and not file (or withdraw or correct) any amendment or
          supplement to such Registration Statement or prospectus to which the
          Holders shall have reasonably objected in writing on the grounds that
          such amendment or supplement does not comply in all material respects
          with the requirements of the Securities Act or of the rules or
          regulations thereunder;

               (vii)  provide a transfer agent and registrar for all Common
          Stock covered by such Registration Statement not later than the
          effective date of such Registration Statement; and

               (viii) promptly list all Common Stock covered by such
          Registration Statement on the AMEX or any securities exchange or
          automated inter-dealer quotation system on which any of the Company
          Common Stock is then listed or traded.

          (b)  The Holders agree that upon receipt of any notice from the
Company of the happening of any event of the kind described in Section 3(a)(v),
the Holders will forthwith discontinue their disposition of Common Stock
pursuant to the Registration Statement until the Holders receive copies of the
supplemented or amended prospectus contemplated by Section 3(a)(v) and, if so
directed by the Company, will deliver to the Company all copies, other than
permanent file copies, then in the possession of the Holders of the prospectus
relating to such Common Stock current at the time of receipt of such notice and
that they will immediately notify the Company, at any time when a prospectus
relating to the registration of such Common Stock is required to be delivered
under the Securities Act, of the happening of any event as a result of which
information previously furnished by the Holders to the Company for inclusion in
such

                                      21
<PAGE>

prospectus contains an untrue statement of a material fact or omits to state any
material fact required to be stated therein or necessary to make the statements
therein not misleading in the light of the circumstances under which they were
made.

          c.   As a condition of the fulfillment of its obligations under this
Agreement, the Company may require the Holders, at their own expense, to furnish
the Company with such information and undertakings regarding such Holders and
the distribution of such securities as the Company may from time to time
reasonably request in writing to the extent necessary in order to cause the
registration statement to comply with the Securities Act, and the Holders shall
provide such information and make such undertakings as are requested.

          d.   In connection with the preparation and filing of each
registration statement under the Securities Act, the Company will give the
Holders and their respective counsel and accountants, the reasonable opportunity
to participate in the preparation of such Registration Statement, each
prospectus included therein or filed with the Commission and each amendment
thereof or supplement thereto, and will give each of them such reasonable access
to its books and records and such reasonable opportunities to discuss the
business of the Company with its officers and the independent public accountants
who have certified its financial statements as shall be necessary to conduct a
reasonable investigation within the meaning of the Securities Act.

          e.   Promptly after a sale of Common Stock pursuant to the
Registration Statement (assuming that no stop order is in effect with respect to
the registration statement at the time of such sale), the Company shall
cooperate with the Holders and provide the transfer agent for the Common Stock
with such instructions and legal opinions as may be required in order to
facilitate the issuance to the purchaser (or the Holder's broker) of new
unlegended certificates for such Common Stock.

    4.    Indemnification; Contribution.
          -----------------------------

          a.   To the extent permitted by applicable law, the Company shall
indemnify and hold harmless each Holder, each person, if any, who controls such
Holders within the meaning of the Securities Act, and each officer, director,
partner, and employee of such Holders and such controlling person, against any
and all losses, claims, damages, liabilities and expenses (joint or several),
including reasonable attorneys' fees and disbursements and expenses of
investigation, incurred by such party pursuant to any actual or threatened
action, suit, proceeding or investigation, or to which any of the foregoing
persons may become subject under the Securities Act, the Exchange Act or any
other federal or state laws, insofar as such losses, claims, damages,
liabilities and expenses arise out of or are based upon any of the following
statements, omissions or violations (collectively a "Violation"):

               (i)  Any untrue statement or alleged untrue statement of a
          material fact contained in such Registration Statement, including any
          preliminary prospectus or final prospectus contained therein, or any
          amendments or supplements thereto;

                                      22
<PAGE>

               (ii)  The omission or alleged omission to state therein a
          material fact required to be stated therein, or necessary to make the
          statements therein not misleading; or

               (iii) Any violation or alleged violation by the Company of the
          Securities Act, the Exchange Act, any applicable state securities law
          or any rule or regulation promulgated under the Securities Act, the
          Exchange Act or any applicable state securities law; provided,
          however, that the indemnification required by this Section 4(a) shall
          not apply to amounts paid in settlement of any such loss, claim,
          damage, liability or expense if such settlement is effected without
          the consent of the Company (which consent shall not be unreasonably
          withheld), nor shall the Company be liable in any such case for any
          such loss, claim, damage, liability or expense to the extent (and only
          to the extent) that it arises out of or is based upon a Violation
          which occurs in reliance upon and in conformity with written
          information furnished to the Company by the indemnified party
          expressly for use in connection with such registration.

          b.   To the extent permitted by applicable law, each Holder shall
indemnify and hold harmless the Company, each of its directors, each of its
officers who shall have signed the registration statement, each person, if any,
who controls the Company within the meaning of the Securities Act, any other
Holder, any controlling Person of any such other Holder and each officer,
director, partner and employee of such other Holder and such controlling Person,
against any and all losses, claims, damages, liabilities and expenses (joint and
several), including reasonable attorneys' fees and disbursements and expenses of
investigation, incurred by such party pursuant to any actual or threatened
action, suit, proceeding or investigation, or to which any of the foregoing
Persons may otherwise become subject under the Securities Act, the Exchange Act
or any other federal or state laws, insofar as such losses, claims, damages,
liabilities and expenses arise out of or are based upon any Violation, in each
case to the extent (and only to the extent) that such Violation occurs in
reliance upon and in conformity with written information furnished by such
Holder expressly for use in connection with such registration; provided,
                                                               --------
however, that the indemnification required by this Section 4(b) shall not apply
-------
to amounts paid in settlement of any such loss, claim, damage, liability or
expense if settlement is effected without the consent of the relevant Holder
(which consent shall not be unreasonably withheld); and, provided further that
                                                         -------- -------
in no event shall the amount of any indemnity under this Section 4(b) exceed the
gross proceeds from the applicable offering received by such Holder.

          c.   Promptly after receipt by an indemnified party under this Section
4 of notice of the commencement of any action, suit, proceeding, investigation
or threat thereof made in writing for which such indemnified party may make a
claim under this Section 4, such indemnified party shall deliver to the
indemnifying party a written notice of the commencement thereof and the
indemnifying party shall have the right to participate in, and, to the extent
the indemnifying party so desires, jointly with any other indemnifying party
similarly noticed, to assume the defense thereof with counsel reasonably
satisfactory to the indemnified party;

                                      23
<PAGE>

provided, however, that an indemnified party shall have the right to retain its
own counsel at its own expense (except as specifically provided below). The
failure to deliver written notice to the indemnifying party within a reasonable
time following the commencement of any such action shall not relieve such
indemnifying party of any liability to the indemnified party under this Section
4 except, if and to the extent that the indemnifying party is actually
prejudiced thereby, but in no event shall it relieve the indemnifying party of
any liability that it may have to any indemnified party otherwise than pursuant
to this Section 4. Any fees and expenses incurred by the indemnified party
(including any fees and expenses incurred in connection with investigating or
preparing to defend such action or proceeding) shall be paid to the indemnified
party, as incurred, within sixty (60) days of written notice thereof to the
indemnifying party (regardless of whether it is ultimately determined that an
indemnified party is not entitled to indemnification hereunder, but in such
event such amounts shall be immediately refunded). Any such indemnified party
shall have the right to employ separate counsel in any such action, claim or
proceeding and to participate in the defense thereof, but the fees and expenses
of such counsel shall be the expenses of such indemnified party unless (i) the
indemnifying party has agreed to pay such fees and expenses or (ii) the
indemnifying party shall have failed to promptly assume the defense of such
action, claim or proceeding or (iii) the named parties to any such action, claim
or proceeding (including any impleaded parties) include both such indemnified
party and the indemnifying party, and such indemnified party shall have been
advised by counsel that there may be one or more legal defenses available to it
which are different from or in addition to those available to the indemnifying
party and that the assertion of such defenses would create a conflict of
interest such that counsel employed by the indemnifying party could not
faithfully represent the indemnified party, it being understood, however, that
the indemnifying party shall not, in connection with any one such action, claim
or proceeding or separate but substantially similar or related actions, claims
or proceedings in the same jurisdiction arising out of the same general
allegations or circumstances, be liable for the reasonable fees and expenses of
more than one separate firm of attorneys (together with appropriate local
counsel) at any time for all such indemnified parties. No indemnifying party
shall be liable to an indemnified party for any settlement of any action,
proceeding or claim without the written consent of the indemnifying party, which
consent shall not be unreasonably withheld.

          d.   If the indemnification required by this Section 4 from the
indemnifying party is unavailable to an indemnified party hereunder in respect
of any losses, claims, damages, liabilities or expenses referred to in this
Section 4:

               (i)  The indemnifying party, in lieu of indemnifying such
          indemnified party, shall contribute to the amount paid or payable by
          such indemnified party as a result of such losses, claims, damages,
          liabilities or expenses in such proportion as is appropriate to
          reflect the relative fault of the indemnifying party and indemnified
          parties in connection with the actions which resulted in such losses,
          claims, damages, liabilities or expenses, as well as any other
          relevant equitable considerations.  The relative fault of such
          indemnifying party and indemnified parties shall be determined by
          reference to, among other things, whether any violation has been
          committed by, or relates to information supplied by, such

                                      24
<PAGE>

          indemnifying party or indemnified parties, and the parties' relative
          intent, knowledge, access to information and opportunity to correct or
          prevent such Violation; provided however, that in no event shall the
          obligation of any indemnifying party to contribute under this clause
          (i) exceed the amount that such indemnifying party would have been
          obligated to pay by way of indemnification if the indemnification
          provided for in Section 4(a) had been available under the
          circumstances. The amount paid or payable by a party as a result of
          the losses, claims, damages, liabilities and expenses referred to
          above shall be deemed to include, subject to the limitations set forth
          in Section 4(a) and (b), any legal or other fees or expenses
          reasonably incurred by such party in connection with any investigation
          or proceeding.

               (ii)  The parties hereto agree that it would not be just and
          equitable if contribution pursuant to this Section 4(d) were
          determined by pro rata allocation or by any other method of allocation
          that does not take into account the equitable considerations referred
          to in Section 4(d)(i).  No person guilty of fraudulent
          misrepresentation within the meaning of Section 11(f) of the
          Securities Act shall be entitled to contribution from any person who
          was not guilty of such fraudulent misrepresentation.

          e.   The obligations of the Company and the Holders under this Section
4 shall survive the completion of any offering of Common Stock pursuant to a
registration statement.

     5.   Rule144; Exchange Act Filings.  The Company shall file as and when
          -----------------------------
applicable, on a timely basis, all reports required to be filed by it under the
Exchange Act. If, for any reason the Company is not required to file reports
pursuant to the Exchange Act, upon the request of any Holder, the Company shall
make publicly available the information specified in subparagraph (c)(2) of Rule
144 of the Securities Act, and take such further action as may be reasonably
required from time to time and as may be within the reasonable control of the
Company, to enable the Holders to transfer the Common Stock to a transferee
without registration under the Securities Act within the limitation of the
exemptions provided by Rule 144 under the Securities Act or any similar rule or
regulation hereafter adopted by the Commission. The Company further covenants
and agrees that it will furnish to each Holder so long as such Holder owns
Common Stock promptly upon request, (i) a written statement by the Company as to
the status of its compliance with the reporting requirements of Rule 144, the
1933 Act and the 1934 Act, (ii) a copy of the most recent annual or quarterly
report of the Company and such other reports and documents so filed by the
Company, and (iii) such other information as may be reasonably requested to
permit the Holders to sell such securities pursuant to Rule 144 without
registration.

     6.   Transfer or Assignment of Registration Rights.  The rights of a
          ---------------------------------------------
Holder provided herein to cause the Company to register the Common Stock may be
transferred or assigned only with respect to Common Stock transferred to an
affiliate of such Holder.

                                      25
<PAGE>

                                  COUNTERPART
                                  -----------

     THIS INSTRUMENT forms part of the Stockholders Agreement (the "Agreement")
made as of the 4th day of December, 1996 among Exigent Diagnostics, Inc.,
SmithKline Beecham Diagnostics Systems Co., Spencer Trask Securities
Incorporated, Exigent Partners, L.P., W. Vickery Stoughton, Thomas H. Grove,
Kenneth B. Asarch, William S. Knight, Donald S. Wong, Ashok K. Sawhney, Philip
B. Smith and the Investors, and any additional Stockholders (as such terms are
defined in the Agreement) of the Corporation, from time to time as such
Agreement has been or shall hereafter be amended in accordance with the terms
thereof, which Agreement permits execution by counterpart. The undersigned
hereby acknowledges having received a copy of the said Agreement (which is
annexed hereto as Schedule I) and having read the said Agreement in its
entirety, and for good and valuable consideration, receipt and sufficiency of
which is hereby acknowledged, hereby agrees that the terms and conditions of the
said Agreement shall be binding upon the undersigned as a Stockholder and such
terms and conditions shall inure to the benefit of the binding upon the
undersigned and its successors and permitted assigns.


     IN WITNESS WHEREOF, the undersigned has executed this instrument this
_____ day of March, 2000.



                                             __________________________________
                                             Felix Hernandez