EMPLOYMENT AGREEMENT


         THIS AGREEMENT is made April 1, 1997 by and between BioTime,  Inc. (the
"Company"), and Ronald S. Barkin, Esq. (the "Employee").

                              W I T N E S S E T H:

         WHEREAS,  the  Company  desires to employ  Employee,  and  Employee  is
willing  to  accept  such  employment,  all  on the  terms  and  subject  to the
conditions hereinafter set forth;

         NOW,   THEREFORE,   in   consideration  of  the  terms  and  conditions
hereinafter set forth, the parties hereto agree as follows:

         1. Employment. The Company hereby employs Employee, and Employee hereby
accepts  employment  with the  Company  on the terms and  conditions  herein set
forth.

         2. Term of Agreement.  This  Agreement  shall commence on April 1, 1997
and shall  continue  in effect  until March 31,  2002 (the  "Expiration  Date"),
unless terminated pursuant to the express provisions of this Agreement.

         3.  Renewal.  This  Agreement  shall be  renewed  automatically  for an
additional one (1) year period on April 1, 2002 and on each anniversary thereof,
unless one party gives the other advance  written notice of non-renewal at least
sixty  (60) days prior to such  date.  Either  party may elect not to renew this
Agreement with or without cause.

         4.  Position;  Duties.  Employee  shall be employed in the position and
shall  perform  the  duties  and  functions  set  forth on  EXHIBIT  A, and such
additional duties and functions as are normally carried out by an executive in a
comparable position with a developer of pharmaceutical or medical products,  and
as the Board of Directors or a duly authorized officer of the Company shall from
time to  time  reasonably  determine.  Employee  shall  devote  his or her  best
efforts,  skills and  abilities to the  Company's  business  pursuant to, and in
accordance with, reasonable business policies and procedures, as fixed from time
to time by the Board of  Directors  of the Company  (the "Board of  Directors").
Employee  covenants  and  agrees  that he or she will  faithfully  adhere to and
fulfill  such  policies  as are  established  from  time to time by the Board of
Directors.

         5. Compensation

                  5.1 Salary and Bonuses. During the term of this Agreement, the
Company shall pay to the Employee:


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                  5.1.1 Base Salary. A base annual salary (the "Base Salary") in
the following  amounts:  Ninety-Two  Thousand Dollars  ($92,000) during the year
beginning  April 1,  1997 and  ending on March 31,  1998;  Ninety-Nine  Thousand
Dollars  ($99,000)  during the year beginning  April 1, 1998 and ending on March
31, 1999; One Hundred Six Thousand Dollars  ($106,000) during the year beginning
April 1, 1999 and ending March 31, 2000; One Hundred  Thirteen  Thousand Dollars
($113,000)  during the year  beginning  April 1, 2000 and ending March 31, 2001;
and One Hundred Twenty  Thousand  Dollars  ($120,000)  during the year beginning
April 1, 2001 and ending March 31, 2002; and One Hundred  Twenty-Seven  Thousand
Dollars  ($127,000.00)  during the year beginning April 1, 2002 and ending March
31, 2003. The Base Salary shall be payable in equal semi-monthly installments or
in such other  installments as may be agreed upon between the parties.  The Base
Salary  may be  increased  from time to time in the  discretion  of the Board of
Directors.

                  5.1.2 The Company shall pay all premiums on Employee's present
disability policy.

                  5.1.3 Bonuses.  The Company may pay Employee such bonuses,  if
any, as the Board of Directors may, from time to time determine.

                  5.2 Benefit  Plans.  Employee shall be eligible (to the extent
he or she qualifies) to participate in any retirement,  pension,  life,  health,
accident and disability  insurance,  stock option plan or other similar employee
benefit  plans  which may be adopted by the  Company  (or any other  member of a
consolidated group of which the Company is a part) for its executive officers or
other employees.

                  5.3  Expense   Reimbursement.   The  Company  shall  reimburse
Employee for all reasonable expenses incurred by Employee in connection with the
performance of his or her employment  duties,  subject to the Company's policies
and procedures in effect from time to time,  and provided that Employee  submits
supporting vouchers.

                  5.4 Vacation;  Sick Leave.  Employee shall be entitled to four
weeks of vacation, without reduction in compensation, during each calendar year.
Such vacation  shall be taken at such time as is  consistent  with the needs and
policies of the  Company.  All  vacation  days shall  accrue  based upon days of
service.  The Company  may,  from time to time,  adopt  policies  governing  the
disposition of unused vacation days remaining at the end of the Company's fiscal
year; which policies may govern whether unused vacation days will be paid, lost,
or carried over into subsequent fiscal years. Employee shall also be entitled to
leave from work, without reduction in compensation, due to illness to the extent
allowed by the Company  consistent  with its policies and procedures and subject
to the provisions of this  Agreement  governing  termination  due to disability,
sickness or illness.


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         6. Termination.  This Agreement shall terminate prior to the Expiration
Date upon the happening of any of the following events:

                  6.1 Death.  Automatically and without notice upon the death of
Employee;

                  6.2 Voluntary Termination by Employee. By Employee voluntarily
leaving  the employ of the  Company  with or without  the consent of the Company
(which Employee shall be entitled to do upon thirty (30) days written notice);

                  6.3  Disability.  Upon written notice of termination  from the
Company  to  Employee,  after  Employee  becomes  disabled,  either  totally  or
partially,  for a period of ninety (90) days during any one hundred  fifty (150)
day period,  so that he or she is prevented from performing his or her principal
duties pursuant to this Agreement;  provided,  that the Company's  obligation to
pay the compensation due under Section shall continue until this Agreement is so
terminated.

                  6.4 For Cause. Upon discharge of Employee,  on written notice,
by the Board of  Directors  on grounds  of: (i)  conviction  of a crime of moral
turpitude;  (ii) deliberate failure to carry out the reasonable  policies of the
Board  of  Directors,  as they  may  relate  to  Employee's  duties  under  this
Agreement;  (iii) chronic  alcohol or drug abuse;  (iv) fraud,  embezzlement  or
misappropriation  of Company assets; (v) disloyal,  dishonest or illegal conduct
in the course of his or her employment;  or (vi) a material default or breach of
any of the  covenants  made by Employee in this  Agreement.  The written  notice
delivered by the Board of Directors shall specify the ground for termination and
shall be supported by a statement of all relevant facts  constituting  cause for
termination.  Any  termination  under this Section shall be deemed a termination
for "cause".

                  6.5 Notice and  Opportunity to Cure. If the Company intends to
terminate  this  Agreement  under clause (ii) or (vi) of Section , and if all of
Employee's acts or omissions giving rise to such determination to terminate this
Agreement  are,  in the  reasonable  determination  of the  Board of  Directors,
susceptible to substantially complete cure by Employee within a period of thirty
(30) days, the written notice given to Employee  pursuant to Section shall state
that the effective date of  termination  shall be thirty (30) days from the date
of such  notice,  and such  notice  shall be  rescinded  if  Employee  effects a
substantially complete cure within such thirty (30) day period.


                  6.6  Payment  of  Compensation  After  Termination  . Upon the
occurrence of any events set forth in Sections  through  hereof or Section , the
Company shall be obligated to pay to Employee (or Employee's estate in the event
of Employee's death) (i) the compensation due him or her under Section up to the

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date of termination;  (ii) any unpaid bonus  previously  awarded by the Board of
Directors;  and (iii)  compensation  for any earned but unused  vacation,  which
compensation  shall be paid at the Base  Salary  rate in effect at the time such
unused vacation accrued.

                  6.7 Payment Upon  Termination by the Company Without Cause. In
the event this  Agreement is  terminated  by the Company for a reason other than
one of those set forth in Section or Section or Section , the  Company  shall be
required  to  continue  to  pay  Employee,   as  severance   compensation,   the
compensation  due him or her  under  Section  , for the  unexpired  term of this
Agreement  (without regard to Section 3). Such severance  compensation  shall be
paid for a period equal to the number of weeks  remaining in the unexpired  term
of this  Agreement  (without  regard to Section ). Employee may elect to receive
the severance  compensation (or such part of the severance compensation as shall
then remain  unpaid) in a lump sum. Such election may be made by written  notice
to the Company,  and if such  election is made the lump sum shall be paid by the
Company within ten (10) days after such notice.

                  6.8 Change of  Control.  Notwithstanding  the  foregoing,  the
Company or its  successor,  or Employee may terminate  this  Agreement,  with or
without  cause,  in connection  with a Change of Control of the Company.  In the
event of such a  termination,  the  Company  shall pay  Employee  on the date of
termination a lump sum payment equal to the greater of (a) 2.99 times Employee's
"Base  Amount"  and (b) the  compensation  due him or her under  Section for the
unexpired  term of this  Agreement  (without  regard to Section ). Such  payment
shall be in addition to any unpaid  amounts  otherwise  then due Employee  under
Section of this Agreement. Any termination of this Agreement, except termination
under Sections through , within twelve months after either (i) the earliest date
on which the Company enters into a letter of intent, memorandum of agreement, or
similar document leading to a Change of Control, or (ii) the effective date of a
Change  of  Control,  shall  be  deemed  conclusively  to  be a  termination  in
connection  with a Change of Control.  If the Company or its successor  causes a
material reduction in Employee's responsibilities or compensation after a Change
of Control,  then Employee may at Employee's  option  terminate  this  Agreement
under  Section  any time  within  one  hundred  eighty  (180)  days  after  such
reduction,  and such resignation shall be deemed a termination by the Company in
connection  with a Change of Control and shall entitle  Employee to the benefits
of this  Section . For purposes of this  Agreement,  the  following  definitions
shall apply.

                  6.8.1 "Change of Control" means (i) the  acquisition of Voting
Securities  of the  Company by a Person or an  Affiliated  Group  entitling  the
holder  thereof to elect a majority of the  directors of the Company;  provided,
that an  increase  in the  amount  of  Voting  Securities  held by a  Person  or
Affiliated  Group who previously  held sufficient  Voting  Securities to elect a
majority of the directors shall not constitute

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a Change of  Control;  and  provided,  further,  that an  acquisition  of Voting
Securities by one or more Persons acting as an underwriter in connection  with a
sale or distribution of such Voting  Securities shall not constitute a Change of
Control under this clause (i); (ii) the sale of all or substantially  all of the
assets of the Company; or (iii) a merger or consolidation of the Company with or
into  another  corporation  or entity in which the  stockholders  of the Company
immediately  before such merger or  consolidation  do not own, in the aggregate,
Voting Securities of the surviving corporation or entity (or the ultimate parent
of the surviving  corporation or entity)  entitling  them, in the aggregate (and
without  regard to  whether  they  constitute  an  Affiliated  Group) to elect a
majority of the  directors or persons  holding  similar  powers of the surviving
corporation  or entity (or the ultimate  parent of the surviving  corporation or
entity); provided,  however, that in no event shall any transaction described in
clauses  (i),  (ii) or  (iii)  be a  Change  of  Control  if all of the  Persons
acquiring Voting Securities or assets of the Company or merging or consolidating
with the  Company  are one or more  direct  or  indirect  subsidiary  or  parent
corporations of the Company.

                  6.8.2  "Voting  Securities"  means shares of capital  stock or
other equity  securities  entitling the holder thereof to regularly vote for the
election of directors (or for person performing a similar function if the issuer
is not a corporation), but does not include the power to vote upon the happening
of some condition or event which has not yet occurred.

                  6.8.3 "Person"  means any natural  person or any  corporation,
partnership,   limited  liability  company,   trust,   unincorporated   business
association or other entity.

                  6.8.4  "Affiliated  Group"  means (i) a Person and one or more
other Persons in control of,  controlled  by, or under common  control with such
Person;  and (ii) two or more Persons who, by written  agreement among them, act
in concert to acquire  Voting  Securities  entitling them to elect a majority of
the directors of the Company.

         7. Renegotiation.  Employee shall be entitled to seek a modification of
this Agreement prior to the Expiration Date if the market value of the Company's
outstanding  capital stock exceeds  $100,000,000.  The Company will negotiate in
good faith with Employee in connection with any such request by the Employee for
such a modification of this Agreement.

         8.  Intellectual  Property  Agreement.  Employee  acknowledges that the
Intellectual Property Agreement  concurrently executed and delivered by Employee
shall remain in effect and shall not be affected by the terms of this  Agreement
or the termination of this Agreement.


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         9. Entire  Agreement.  The provisions of this Agreement,  including the
exhibits  attached to this Agreement,  constitute the entire  agreement  between
Employee and the Company with respect to the subject  matter of this  Agreement,
and  supersede  any prior oral  understanding.  No  modification,  supplement or
discharge of this Agreement shall be effective unless in writing and executed on
behalf of the party to be charged.

         10.  Waiver.  No  waiver  by  either  party of any  condition,  term or
provision of this Agreement  shall be deemed to be a waiver of any proceeding or
succeeding  breach of the same or of any other  condition,  term or provision of
this Agreement.

         11.  Assignability.  This Agreement,  and the rights and obligations of
the parties under this Agreement,  may not be assigned by Employee.  The Company
may  assign  any of its  rights and  obligations  under  this  Agreement  to any
successor or surviving corporation resulting from a merger, consolidation,  sale
of assets or stock, or other corporate  reorganization,  upon condition that the
assignee  shall  assume,  either  expressly  or by  operation of law, all of the
Company's obligations under this Agreement.

         12.   Counterparts.   This   Agreement   may  be  executed  in  several
counterparts,  each of  which  shall  be  deemed  an  original  but all of which
together shall constitute one and the same instrument.

         13. Construction.  This Agreement shall be construed in accordance with
the laws of the State of California.

         14. Survival.  This Section and the covenants and agreements  contained
in Sections  5.3, 6.6, 6.7, and 6.8 of this Agreement shall survive  termination
of Employee's employment.

         15. Notices.  Any notices or other communication  required or permitted
to be given under this Agreement shall be in writing and shall be sent by United
States mail, first class certified or registered postage prepaid, return receipt
requested, or personally delivered to the parties at the following addresses:

         To the Company:           BioTime, Inc.
                                   935 Pardee Street
                                   Berkeley, California 94710
                                   Attention: President

         To Employee:              Ronald S. Barkin, Esq.
                                   935 Pardee Street
                                   Berkeley, California 94710


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A notice sent by certified or registered  mail shall be deemed  delivered on the
fourth  day after  deposit in the  United  States  mail,  postage  prepaid,  and
addressed  as  aforesaid.  Any party may change its address for notice by giving
notice to the other party in the manner provided in this Section.

         16. Unenforceable  Provisions. If all or part of any one or more of the
provisions  contained  in this  Agreement  is for any reason held to be invalid,
illegal,  or  unenforceable  in any  respect,  the  invalidity,  illegality,  or
unenforceability shall not affect any other provisions, and this Agreement shall
be  equitably  construed  as if it did not  contain  the  invalid,  illegal,  or
unenforceable provision.

         17. Section  Headings.  Section headings are for the convenience of the
parties and do not form a part of this Agreement.

         18.  Section and Other  References.  References  in this  Agreement  to
Sections,  subsections,  and Exhibits are references to sections and subsections
in this  Agreement  and exhibits  attached to this  Agreement  unless  specified
otherwise.


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

                                                      /s/ Ronald S. Barkin
EMPLOYEE:                                       _______________________________
                                                      Ronald S. Barkin, Esq.



COMPANY:                                                 BIOTIME, INC.


                                                 By: __________________________


                                              Title: __________________________

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                                    EXHIBIT A


                           DUTIES AND RESPONSIBILITIES


The Executive Vice  President  shall  participate  in formulating  the Company's
operating and financial plans in conjunction with the Board of Directors and the
Corporate Officers.  In such capacity,  and subject to the ultimate authority of
the Board of Directors,  the Executive Vice President shall assist in the review
and approval or disapproval of proposed plans, programs, and contracts for joint
ventures  and  investments  in  other  corporations,  partnerships  and  similar
entities,  and for  obtaining  debt and equity  financing  for the  Company.  As
requested  by the  Board  of  Directors  or the  Chief  Executive  Officer,  the
Executive  Vice  President  shall  represent the Company in the  negotiation  of
contracts and  agreements  with third  parties,  including,  but not limited to,
license distribution and manufacturing contracts in regulatory matters involving
government or administrative  bodies having jurisdiction over the Company or its
operations,  in obtaining debt and equity financing, and in other aspects of the
Company's affairs.

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