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                                                                     EXHIBIT 4.9

                                   NEW NOTE
                                   --------


THIS NOTE HAS NOT BEEN REGISTERED UNDER THE UNITED STATES SECURITIES ACT OF
1933, AS AMENDED, OR THE SECURITIES LAWS OF ANY STATE.  THIS NOTE MAY NOT BE
SOLD OR TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION
THEREFROM.


                                 PROMISSORY NOTE

$2,000,000                                                      Philadelphia, PA
                                                                   June 21, 1999


          FOR VALUE RECEIVED, CARESIDE, INC., a Delaware corporation with
offices at 6100 Bristol Parkway, Culver City, California 90230 ("Maker")
promises to pay to the order of S.R. One, Limited, a Pennsylvania Business
Trust, ("Payee"), or to such other person or at such other place as Payee may
designate from time to time in writing, the principal amount of Two Million
Dollars ($2,000,000) in lawful money of the United States of America, together
with such interest as may be payable as hereinafter provided.  This Note is
issued pursuant to the Securities Purchase Agreement dated December 17, 1998
between Maker and Payee (the "Securities Purchase Agreement") and as modified by
the Securities Conversion Agreement, dated as of June 14, 1999, between Maker
and Payee (the "Securities Conversion Agreement").  This note represents the
remaining balance under those certain notes dated December 28, 1998 and January
13, 1999 each in the original principal amount of $1,500,000 (the "Original
Notes").  Simultaneously with the issuance of this Note, $1,000,000 of the
principal amount under the Original Notes, together with accrued interest
thereon, was converted into preferred stock of Maker (the "Conversion").  In
connection with the Conversion, Maker and Payee agreed to certain changes to the
terms of the Original Notes.  The Original Notes having been surrendered and
canceled, this Note is being issued as an amendment and restatement of the
Original Notes insofar as they represent the portion of the principal and
interest thereunder not converted to preferred stock (the "Remaining Balance").
Interest on the Remaining Balance accrued but not paid prior to the date hereof
shall be due and owing pursuant to this Note.

          1.   Maturity.  The principal amount outstanding under the Note will
               --------
be due and payable at the earliest to occur of (i) the closing of a private
equity financing of at least $8,000,000, or (ii) December 17, 1999 ("Maturity").

          2.   Interest Payments. Interest payable on the outstanding principal
               -----------------
will be calculated at the rate of eight percent (8%) per annum from the date
hereof through and including June 30, 1999.  Commencing July 1, 1999 interest
shall be calculated at the rate of ten percent (10%) per annum.  In either case,
interest shall be payable in cash on a quarterly basis on the last business day
of each calendar quarter, or on Maturity if other than the last day of a
calendar
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quarter, commencing with the last business day of the calendar quarter which
includes the date hereof.

          3.   Optional Prepayment.
               -------------------

               (a)  From and after the date hereof, provided demand for
repayment has not been made, Maker shall have the privilege at any time and from
time to time of prepaying this Note in whole or in part (each, a "Prepayment"),
provided that Maker sends a notice (each, a "Prepayment Notice") to Payee at
least 15 days prior to the date of such prepayment (each, a "Prepayment Date").
There shall be no premium or penalty in connection with any Prepayment. Each
Prepayment shall be applied first against accrued interest, if any, and then
against principal outstanding in the inverse order of the maturity of the
installments thereof. Each Prepayment Notice shall set forth the Prepayment Date
and the amount of the Prepayment, specifying the amount thereof being applied
against accrued interest and the amount thereof being applied against principal.

          4.   Conversion.  All of any portion of the remaining principal, plus
               ----------
accrued interest thereon, shall be convertible at the option of Payee,
exercisable after December 1, 1999, into shares of Series A Convertible
Preferred Stock determined on the same basis as the terms set forth in the
Securities Conversion Agreement.

          5.   Security.  The indebtedness outstanding under this Note will
               --------
be unsecured.  Maker covenants that it will not create, incur, assume or permit
any mortgage, pledge, lien, security interest or other preferential arrangement,
charge or encumbrance of any nature upon or with respect to the assets of the
Maker except for mortgages, pledges, liens, security interests or other
preferential arrangements, charges or encumbrances on the assets of the Maker
incurred, assumed or permitted pursuant to any lease financing for up to
$3,000,000 undertaken by the Maker.

          6.   Seniority.  The indebtedness outstanding under this Note will be
               ---------
considered senior debt and will not be subordinated to any other indebtedness of
the Maker except insofar as Maker has granted security to Finova Technology
Finance, Inc. in connection with equipment lease financing obtained from such
lender.

          7.   Events of Default.  The occurrence of one or more of the
               -----------------
following events (after the expiration of any stated notice or cure period)
shall constitute an event of default ("Event of Default") hereunder:

               (a)  Maker shall fail to make any payment due to Payee under this
Note within ten (10) days after the same shall become due and payable, whether
at Maturity, by acceleration or otherwise;

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               (b)  If Maker becomes insolvent, bankrupt or generally fails to
pay its debts as such debts become due; is adjudicated insolvent or bankrupt;
admits in writing its inability to pay its debts; or shall suffer a custodian,
receiver or trustee for it or substantially all of its property to be appointed
and if appointed without its consent, not be discharged within ninety (90) days;
makes an assignment for the benefit of creditors; or suffers proceedings under
any law related to bankruptcy, insolvency, liquidation or the reorganization,
readjustment or the release of debtors to be instituted against it, and if
contested by it, not dismissed or stayed within ninety (90) days; if proceedings
under any law related to bankruptcy, insolvency, liquidation, or the
reorganization, readjustment or the release of debtors is instituted or
commenced by Maker; if any order for relief is entered relating to any of the
foregoing proceedings; if Maker shall call a meeting of its creditors with a
view to arranging a composition or adjustment of its debts; or if Maker shall by
any act or failure to act indicate its consent to, approval of or acquiescence
in any of the foregoing;

               (c)  Maker fails to perform in accordance with any other terms or
conditions in this Note, Securities Purchase Agreement or the Securities
Conversion Agreement between Maker and Payee and Maker has failed to cure the
same within thirty (30) days following its receipt of written notice of said
Event of Default hereunder or of a default thereunder;

               (d)  Maker sells or otherwise transfers substantially all of its
assets, discontinues its business, voluntarily or involuntarily dissolves, or
more than fifty percent (50%) of the voting power of the equity of Maker is
transferred to a single acquirer or group of acquirers acting in concert in a
single transaction or series of related transactions.

          8.   Remedies.  Upon the occurrence of any Event of Default, at the
               --------
option of Payee:

               (a)  the entire unpaid principal sum outstanding hereunder plus
any and all interest accrued thereon plus all other sums due and payable to
Payee hereunder shall become immediately due and payable; and

               (b)  Payee may exercise any and all other rights and remedies at
law or in equity.

          9.   Remedies Cumulative, etc.
               -------------------------

               (a)  No right or remedy conferred upon or reserved to Payee
hereunder or now or hereafter existing at law or in equity is intended to be
exclusive of any other right or remedy, and each and every such right or remedy
shall be cumulative and concurrent, and in addition to every other such right or
remedy, and may be pursued singly, concurrently, successively or otherwise, at
the sole discretion of Payee, and shall not be exhausted by any one exercise
thereof but may be exercised as often as occasion therefor shall occur.

                                      -3-
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               (b)  Maker agrees that any action or proceeding against it to
enforce this Note may be commenced in state or federal court in any county in
the State of Delaware.

          10.  No Setoff.  Maker shall not be permitted to set off any
               ---------
obligation owed to Payee hereunder against any obligations owed by Payee to
Maker, if any, unless such obligation setting off payments hereunder has been
finally determined to be owed to Maker and such determination is not appealable
by Payee.

          11.  Costs and Expenses.  Following the occurrence of any Event of
               ------------------
Default, Maker shall pay upon demand all costs and expenses (including all
attorneys' fees and expenses) incurred by Payee in the exercise of any of its
rights, remedies or powers to enforce this Note and any amount thereof not paid
promptly following demand therefor shall be added to the principal sum hereunder
and shall bear interest as set forth in Section 2 hereof, from the date of such
demand until paid in full.

          12.  Notices.  All notices required to be given to any of the parties
               -------
hereunder shall be in writing and shall be deemed to have been sufficiently
given for all purposes when presented personally to such party or sent by
certified or registered mail, return receipt requested, to such party at its
address set forth below:

     If to Maker:     CARESIDE, INC.
     -----------
                      6100 Bristol Parkway
                      Culver City, CA 90230
                      Attn:  President and
                             Chief Executive Officer
                      Facsimile No.: 310-338-6789

     With a copy to:  Pepper Hamilton LLP
     --------------
                      3000 Two Logan Square
                      18th & Arch Streets
                      Philadelphia, PA 19103
                      Attn:  Julia D. Corelli, Esq.

     If to Payee:     S.R. One, Limited
     -----------
                      4 Towers Bridge
                      200 Barr Harbor Drive
                      Suite 250
                      West Conshohocken, PA 19428
                      Attn:  Ms. Brenda Gavin
                      Facsimile No.: ____________

          Such notice shall be deemed to be given when received if delivered
personally or three (3) business days after the date mailed to a recipient in
the same country as the sender, or

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seven (7) business days to any other recipient. Any notice mailed shall be sent
by certified or registered mail. Any notice of any change in such address shall
also be given in the manner set forth above. Whenever the giving of notice is
required, the giving of such notice may be waived in writing by the party
entitled to receive such notice.

          13.  Severability.  In the event that any provision of this Note is
               ------------
held to be invalid, illegal or unenforceable in any respect or to any extent,
such provision shall nevertheless remain valid, legal and enforceable in all
such other respects and to such extent as may be permissible.  Any such
invalidity, illegality or unenforceability shall not affect any other provisions
of this Note, but this Note shall be construed as if such invalid, illegal or
unenforceable provision had never been contained herein.

          14.  Successors and Assigns.  This Note inures to the benefit of Payee
               ----------------------
and binds Maker, and its respective successors and assigns, and the words
"Payee" and "Maker" whenever occurring herein shall be deemed and construed to
include such respective successors and assigns.

          15.  Entire Agreement. This Note embodies the entire understanding and
               ----------------
agreement between the parties hereto and thereto with respect to the subject
matter hereof and thereof and supersedes all prior agreements, understandings
and inducements, whether express or implied, oral and written.

          16.  Modification of Agreement. This Note may not be modified, altered
               -------------------------
or amended, except by an agreement in writing signed by both Maker and Payee.

          17.  No Presentment, Etc.  Maker hereby waives presentment, demand,
               -------------------
notice, protest and all other demands and notices in connection with the
delivery, acceptance, performance, Event of Default or enforcement of this Note.

          18.  No Waiver.  Payee shall not, by any act, delay, omission or
               ---------
otherwise, be deemed to have waived any of its rights or remedies hereunder,
unless such waiver shall be in writing and signed by Payee.  A waiver on any one
occasion shall not be construed as a bar to or waiver of any such right or
remedy on any future occasion.

          19.  Governing Law.  This Note shall be governed by and construed in
               -------------
accordance with the laws of the State of Delaware.

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          IN WITNESS WHEREOF, Maker has duly executed this Promissory Note this
21st day of June 1999.

                                   CARESIDE, INC.



                                   By:  /s/ James Koch
                                       -----------------------------------
                                   Name:    James Koch
                                   Title:   Chief Financial Officer

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