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                              EMPLOYMENT AGREEMENT


     EMPLOYMENT AGREEMENT (the "Agreement") made as of the 29th day of January,
1997 by and between Biocircuits Corporation, a Delaware corporation (the
"Company"), and Donald Hawthorne ("Employee").

1.   SERVICES, DUTIES AND ACCEPTANCE

     1.1  TERM; DUTIES.  The Company hereby employs Employee for the Employment
Term (as defined in Section 2 hereof) as Vice President and Chief Financial
Officer of the Company.  The parties agree that Employee will engage in an
active job search effective January 1, 1997, and will be permitted reasonable
time off to pursue other employment, consistent with his responsibilities.  The
Company hereby agrees to retain the consulting services of Employee during the
Consulting Term (as defined in Section 2 hereof).  Consulting services shall be
provided upon the reasonable request of the Company, but shall not interfere
with any employment responsibilities that Employee may have to another employer
during the Consulting Term.

     1.2  ACCEPTANCE.  Employee hereby accepts such employment and consulting
arrangement and agrees to render the services described above.  Employee shall
perform services hereunder with fidelity and to the best of his ability.

     1.3  PLACE OF EMPLOYMENT.  The duties to be performed by Employee hereunder
during the Employment Term shall be performed in the San Francisco Bay Area as
needed and at the discretion of the Chief Executive Officer.

2.   EMPLOYMENT AND CONSULTING TERM

     The term of Employee's employment under this Agreement (the "Employment
Term") shall commence on the date of this Agreement and continue until the
earliest of (i) September 30, 1997, (ii) the date Employee voluntarily
terminates his Employment or (iii) or the date Employee's employment is
terminated for Cause.  The Consulting Term shall commence at the end of the
Employment Term and end two years thereafter, provided that there shall be no
Consulting Term if Employee's employment is terminated for "Cause" as defined in
Subsection 4.2 hereof) and the Consulting Term shall end if Employee engages in
conduct constituting Cause.

3.   COMPENSATION

     3.1  BASE SALARY.  During the Employment Term and prior to July 1, 1997,
the Company shall pay Employee base salary at the rate in effect immediately
prior to the date of this Agreement.  For the remainder of the Employment Term,
the Company agrees to pay Employee base salary at 50% of such rate.  All base
salary shall be payable in periodic installments in accordance with the
Company's general payroll practices, less such deductions or amounts to be
withheld as shall be required by applicable law and regulations.  Base salary
shall not be paid during the Consulting Term.


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     3.2  EXPENSES.  The Company shall pay or reimburse Employee for all
reasonable expenses actually incurred or paid by Employee during the Employment
Term and the Consulting Term in the performance of his services under this
Agreement, upon presentation of expense statements or vouchers or such other
supporting information as the Company may reasonably require.

     3.3  STOCK OPTIONS.  As compensation for the services to be provided under
this Agreement, Employee's options to purchase common stock shall continue to
vest during the Employment Term and the Consulting Term.  Employee acknowledges
that in accordance with the requirements of the Internal Revenue Code,
Employee's incentive stock options shall be nonstatutory stock options if
exercised more than three months following the termination of the Employment
Term.

     3.4  OTHER BENEFITS.  During the Employment Term, Employee shall be
entitled to all rights and benefits for which he shall be eligible under any
group insurance or other employee benefit plans or arrangements which Company
may, in its sole discretion, provide for its vice-presidential level employees
generally.  During the Consulting Term, Employee shall be eligible for such
rights and benefits only to the extent required by law or the terms of the
Company's group insurance or employee benefit plans or arrangements.

4.   TERMINATION OF EMPLOYMENT

     4.1  DEATH.  If Employee dies during the Employment Term or Consulting
Term, Employee's legal representatives shall be entitled to receive the
compensation provided for hereunder through the last day of the month in which
Employee's death occurs and no other compensation (including option vesting)
shall be paid with respect to Employee's services hereunder as an employee or
consultant.

     4.2  INVOLUNTARY TERMINATION FOR CAUSE.  If Employee engages in conduct
constituting "Cause", the Company may by written notice to Employee terminate
the Employment Term and Employee's right to compensation (including benefits and
option vesting) hereunder shall be limited to that earned on or before the date
of such termination.  For purposes of this Agreement, Cause exists at any time
after the happening of one or more of the following events:  (a)  Employee's
willful misconduct or gross negligence in performance of his duties hereunder,
including Employee's refusal to comply in any material respect with the legal
directives of the Company's Chief Executive Officer or Board of Directors so
long as such directives are not inconsistent with the Employee's position and
duties, and such refusal to comply is not remedied within ten (10) working days
after written notice from the Company, which written notice shall state that
failure to remedy such conduct may result in Termination for Cause; or (b)
Dishonest or fraudulent conduct, a deliberate attempt to do an injury to the
Company, or conduct that materially discredits the Company or its materially
detrimental to the reputation of the Company.

     4.3  INVOLUNTARY TERMINATION WITHOUT CAUSE.  If the Company terminates
Employee's employment without Cause (including in the context of layoff,
restructuring or acquisition) during the Employment Term, his compensation
(including benefits and option vesting) hereunder shall continue until the date
both the Employment Term and the Consulting


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Term would have ended had such termination not occurred, provided that the
Company's obligation to pay base salary and provide benefits shall terminate on
the date Employee accepts other full-time employment.

     4.4  VOLUNTARY TERMINATION WITH GOOD REASON.  A "Voluntary Termination With
Good Reason" shall be deemed to occur if there is an adverse change in the
Employee's position causing such position to be of materially less stature or of
materially less responsibility and, within a 30 day period immediately following
such material change or reduction Employee elects to terminate his employment
voluntarily.  In the event of a Voluntary Termination With Good Reason,
Employee's compensation (including benefits and option vesting) hereunder shall
continue until the date the Employment Term (and if the change or reduction is
not attributable to the hiring of a new Chief Financial Officer, the Consulting
Term) would have ended had such termination not occurred, provided that the
Company's obligation to pay base salary and provide benefits shall terminate on
the date Employee accepts other full-time employment.

     4.5  VOLUNTARY TERMINATION WITHOUT GOOD REASON.  If Employee voluntarily
terminates his employment during the Employment Term other than in a Voluntary
Termination With Good Reason, his entitlement to base salary and benefits
hereunder shall cease on the date of such termination, but his options shall
continue to vest during the Consulting Term.

5.   PROTECTION OF CONFIDENTIAL INFORMATION

     Employee shall continue to be bound by Company's standard proprietary
information agreement.

6.   NOTICES

     All notices, requests, consents and other communications required or
permitted to be given hereunder shall be in writing and shall be deemed to have
been duly given if delivered personally or sent by prepaid telegram, or mailed
first-class, postage prepaid, by registered or certified mail (notices sent by
telegram or mailed shall be deemed to have been given on the date sent), as
follows (or to such other address as either party shall designate by notice in
writing to the other in accordance herewith):

     6.1  If to the Company:
          Biocircuits Corporation
          1324 Chesapeake Terrace
          Sunnyvale, CA  94089
          Attn:  John Kaiser

          copy to:

          Cooley Godward LLP
          Five Palo Alto Square
          3000 El Camino Real
          Palo Alto, CA  94306-2155
          Attn:  Deborah Marshall, Esq.


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     6.2  If to Employee:

          Donald Hawthorne
          260 Windsor Drive
          San Carlos, CA  94070

7.   GENERAL

     7.1  GOVERNING LAW.  This Agreement shall be governed by and construed in
accordance with the laws of the State of California applicable to agreements
made and to be performed entirely within such State.

     7.2  CAPTIONS.  The section headings in this Agreement are for reference
only and shall not in any way affect the interpretation of this Agreement.

     7.3  ENTIRE AGREEMENT.  This Agreement sets forth the entire agreement and
understanding of the parties relating to the subject matter hereof, and
supersedes all prior agreements, arrangements and understandings, written or
oral, relating to the subject matter hereof, including any Employment Agreement.
No representation, promise or inducement has been made by either party that is
not embodied in this Agreement, and neither party shall be bound by or liable
for any alleged representation, promise or inducement not so set forth.

     7.4  ASSIGNABILITY.  Employee's rights and obligations hereunder shall be
assigned by the Company if, and to the extent, comparable rights (including
rights with respect to stock options) and obligations of other executive
officers of the Company are assigned.

     7.5  WAIVERS AND AMENDMENTS.  This Agreement may be amended, modified,
superseded, canceled, renewed or extended, and the terms hereof may be waived,
only by a written instrument executed by both of the parties hereto or, in the
case of a waiver, by the party waiving compliance.  The failure of either party
at any time or times to require performance of any provision hereof shall in no
manner affect the right at a later time to enforce the same.  No waiver by
either party of the breach of any term or covenant contained in this Agreement,
whether by conduct or otherwise, in any one or more instances, shall be deemed
to be, or construed as, or be implied to constitute a waiver or a further or
continuing waiver of any such breach, or a waiver of the breach of any other
term or covenant contained in this Agreement.


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

                                   BIOCIRCUITS CORPORATION



                                   By /s/ John Kaiser
                                     ------------------------

                                   Title: President & CEO
                                         --------------------


                                   EMPLOYEE



                                   /s/ Donald Hawthorne
                                   --------------------------
                                        Donald Hawthorne


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