Exhibit 10.19

PROMISSORY NOTE
(Loan (Mount Vernon))

|$2,340,000.00 |  | Indianapolis, Indiana
October 29, 2002
|------------- |  | --------------------------------------

FOR  VALUE  RECEIVED  the  undersigned   Bioanalytical  Systems,  Inc.  and  BAS
Evansville, Inc., both Indiana corporations (collectively,  Makers),
individually,  jointly  and  severally  promise  to pay to the  order  of  Union
Planters Bank,  N.A.  (Payee),  on or before  May 1,  2008 (the
Maturity Date), the principal sum of Two Million Three Hundred Forty
Thousand Dollars and No Cents ($2,340,000.00) or such lesser sum as is indicated
on Payees  records as having been disbursed by Payee to or for the benefit
of Makers, together with interest prior to the Maturity Date, upon the terms set
forth in this Promissory Note.

1.        
Definitions.   In  addition  to  the  terms  defined  elsewhere  in  this
Promissory Note, the following terms have the meanings indicated for purposes of
this Promissory Note:

| | a.        
l Year TCMI means a Fixed Rate which is equal to the then current
weekly or monthly average, as selected by Lender in its sole discretion, of the
one (1) year U.S. Treasury Constant Maturity Index as published by The Federal
Reserve Board of the United States in the most recent H.15 on or before fifteen
days prior to the Conversion Date, which rate will change at the end of each
such one (1) year interest rate period. If the Federal Reserve Board of the
United States discontinues publication of the H.15, Lender in its sole
discretion will select another authoritative source for said index.
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| | b.        
3 Year TCMI means a Fixed Rate which is equal to the then current
weekly or monthly average, as selected by Lender in its sole discretion, of the
three (3) year U.S. Treasury Constant Maturity Index as published by The Federal
Reserve Board of the United States in the most recent H.15 on or before fifteen
days prior to the Conversion Date, which rate will change at the end of each
such three (3) year interest rate period. If the Federal Reserve Board of the
United States discontinues publication of the H.15, Lender in its sole
discretion will select another authoritative source for said index.
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| | c.        
5 Year TCMI means a Fixed Rate which is equal to the then current
weekly or monthly average, as selected by Lender in its sole discretion, of the
five (5) year U.S. Treasury Constant Maturity Index as published by The Federal
Reserve Board of the United States in the most recent H.15 on or before fifteen
days prior to the Conversion Date, which rate will change at the end of each
such five (5) year interest rate period. If the Federal Reserve Board of the
United States discontinues publication of the H.15, Lender in its sole
discretion will select another authoritative source for said index.
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| | d.        
"Advance" means a disbursement  made to Makers,  or either of them,  pursuant to
this Promissory Note.
| | -----------------------------------------------------------------------------------------------------------------

| | e.        
Applicable Margin means, as applicable, a margin of (i) Two and One
Fourth Percent (2.25%) over the 1 Year TCMI, (ii) Two and One Half Percent
(2.50%) over the 3 Year TCMI, and (iii) Two and Three Fourths Percent (2.75%)
over the 5 Year TCMI.
| | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | f.        
"Conversion Date" means April 18, 2003.
| | --------------------------------------------------

| | g.        
Fixed Rate means, as may be selected by Makers, or either of them,
on or before fifteen days prior to the Conversion Date, (i) the 1 Year TCMI plus
the Applicable Margin, (ii) the 3 Year TCMI plus the Applicable Margin, or (iii)
the 5 Year TCMI plus the Applicable Margin.
| | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | h.        
Loan Agreement means that certain Loan Agreement of even date
herewith among Makers, as Borrowers, and Payee, as Lender, as may be amended
from time to time.
| | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | i.        
Prime Rate means that rate of interest announced from time to time
by Union Planters Bank, N.A. (or any financial institution which may succeed to
the commercial lending business of Union Planters Bank, N.A.) as its prime rate,
which rate shall change on the same date as the date of each change in said
Prime Rate. The Prime Rate is a reference rate and does not necessarily
represent the lowest or best rate actually charged to any customer. Lender may
make commercial loans or other loans at rates of interest at, above or below the
Prime Rate.
| | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Capitalized terms used in this Promissory Note and not otherwise defined in this
Promissory  Note  shall  have the  meanings  ascribed  to such terms in the Loan
Agreement.

2.        
Requests for Advances.  Subject to the terms of the Loan Agreement, until
the Conversion Date, Makers, or either of them, may request and receive Advances
under this  Promissory  Note so long as the balance  outstanding at any one time
does not exceed the face amount of this Promissory Note (i.e., Two Million Three
Hundred Forty Thousand Dollars and No Cents ($2,340,000.00). However, at no time
during the term of this  Promissory  Note may the aggregate  Advances under this
Promissory  Note  exceed  Eighty  Percent  (80%) of the value of the Real Estate
(Mount Vernon) as determined by an independent  appraiser  acceptable to Lender.

3.        
Construction  Loan.  Payee has  approved a Loan to Makers in a  principal
amount not to exceed the face amount of this Promissory Note. The Loan is in the
form of Advances made from time to time by Payee to Makers. This Promissory Note
evidences  Makers  obligation  to  repay  those  Advances.  The  aggregate
principal  amount of debt evidenced by this  Promissory Note shall be the amount
reflected  from time to time in the  records  of Payee but shall not  exceed the
face amount of this Promissory Note.

4.        
Interest.  Prior to the Conversion Date, interest on this Promissory Note
shall accrue at the Prime Rate. On and after the  Conversion  Date,  interest on
this Promissory Note shall accrue at the Prime Rate unless Maker selects a Fixed
Rate on or before fifteen days prior to the Conversion Date. All computations of
interest and fees under this  Agreement  shall be made on the basis of a year of
three hundred sixty (360) days and calculated  for the actual days elapsed.  Any
change in the rate of interest occasioned by a change in the Prime Rate shall be
effective on the same day as the change in the Prime Rate.

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5.        
Repayment.  Makers  will repay the  principal  amount of this  Promissory
Note, and accrued interest thereon, as follows:

| | (a)        
Prior to the Conversion Date,  consecutive  monthly payments of interest only on
the first day of each month, commencing December 1, 2002;
| | ------------------------------------------------------------------------------------------------------------------------------------------------------

| | (b)        
Makers will repay this Loan in consecutive monthly installments of principal and
interest,  based on the applicable  interest rate and the months remaining in an
amortization  period  that begins on the date hereof and extends for a period of
one hundred  eighty  (180)  months  thereafter.  Makers  said  installment
payments shall commence on the Conversion  Date, and shall continue on the first
day of each calendar  month until the Maturity  Date. On the Maturity  Date, the
balance,   plus  accrued  interest,   then  unpaid  shall  be  due  and  payable
immediately.  To the extent  that the  amortization  period  extends  beyond the
Maturity Date, the final payment on the Maturity Date will be a balloon  payment
in  an  amount  sufficient  to  repay  all  remaining  indebtedness  under  this
Promissory  Note.  Principal  and  interest  payments  after  any  change in the
applicable  interest rate or any partial  prepayment will be calculated based on
the  number  of  months   remaining  in  the  one  hundred  eighty  (180)  month
amortization period of this Promissory Note at such time.
| | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | (c)        
In any and all events,  the entire remaining  balance of this Promissory Note is
due and payable on the Maturity  Date.  Acceptance by Payee of any payment which
is less than payment in full of all amounts due and owing at such time shall not
constitute a waiver of Payees  right to receive payment in full at such or
any other time.
| | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Each payment of principal and interest due under this  Promissory  Note shall be
made by Makers to Payee at any of its offices.  All sums paid on this Promissory
Note shall be applied  first to fees and costs of Payee in  connection  with the
enforcement  of  the  terms  and  conditions  of the  Loan  Agreement  and  this
Promissory Note, second to interest accrued to the date of payment,  and finally
to principal.  Each payment due under this Promissory Note shall be made without
set-off or  counterclaim  in immediately  available  funds on a Business Day not
later than 3:30 p.m. Lafayette,  Indiana time. All sums received after such time
shall be  deemed  received  on the next  Business  Day.  If any  installment  of
principal or interest under this  Promissory Note is payable on a day other than
a Business Day, the maturity of such  installment  shall be extended to the next
succeeding  Business Day, and interest shall be payable during such extension of
maturity.

All sums payable hereunder will be payable with  attorneys  fees and costs
of collection and without relief from valuation and  appraisement  laws.  Makers
and all  endorsers  hereof  hereby  severally  waive  presentment  for  payment,
protest,  notice of  protest,  notice of  non-payment  and all other  notices or
demands in  connection  with the  delivery,  acceptance,  performance,  default,
endorsement or guaranty of this Promissory  Note,  notice of loans made,  credit
extended,  collateral  received or delivered,  or other action taken in reliance
hereon and all other demands and notices of any description. Further, Makers and
all endorsers hereof hereby severally consent to extensions of time with respect
to sums payable hereunder and any collateral for this  indebtedness.  Each Maker
consents to any  extension or  postponement  of the time of payment or any other
indulgence to any substitution, exchange or release of or failure to perfect any
security  interest in such collateral,  to the adding or release of any party or
person  primarily or secondarily  liable,  to the acceptance of partial  payment
thereon,  and the  settlement,  compromise or adjustment of any thereof,  all in
such manner and at such time as Payee may deem advisable.

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6.        
Prepayment.  Makers  shall have the right to prepay all or any portion of
the amount outstanding under this Promissory Note accruing interest at the Prime
Rate at any time  without  premium or penalty.  In all other  cases,  Makers may
prepay all or any part of the principal  balance of this  Promissory Note on one
Business Days notice provided that, in addition to all principal, interest
and costs owing at the time of prepayment, Makers pay a prepayment premium equal
to:

[A]  The  NPV  (NPV  calculations  will  be  based  on the  original  contracted
Promissory  Note rate) of interest that would have accrued on the amount prepaid
(under  the  original  terms  and  conditions  of this  Promissory  Note) at the
original LIBOR/SWAP rate through the maturity date:

Minus

[B] The NPV (NPV  calculations  will be based on the  current  LIBOR / SWAP rate
concurrent  with the date of  prepayment) of interest that would have accrued on
the amount prepaid  (under the original terms and conditions of this  Promissory
Note) at the current LIBOR / SWAP rate through the maturity date.

[A] - [B] = Prepayment Premium

In no event shall the prepayment premium be less than zero. Makers  notice
of  their  intent  to  prepay  shall  be  irrevocable.  If the  balance  of this
Promissory  Note is accelerated in accordance  with the terms of this Promissory
Note, the resulting balance due shall be considered a prepayment due and payable
as of the date of acceleration.

Makers agree that the  prepayment  premium is a reasonable  estimate of loss and
not a penalty.  The prepayment  premium is payable as liquidated damages for the
loss of bargain,  and its payment shall not in any way reduce,  affect or impair
any other obligation of Makers under this Promissory  Note. As used herein,  the
following terms have the following definitions:

NPV:  Net Present Value

LIBOR/SWAP:  LIBOR  (London  Interbank  Offered  Rate) is  fixed  each
morning by the British Bankers  Association  (BBA). The LIBOR / SWAP rates to be
used will be on the day of prepayment.

Union Planters  Corporation uses the LIBOR / SWAP as shown in Bloomberg  (USSWAP
Mid) (day count adjusted from actual/360 to actual/actual).

Bloomberg:  Is  an  independent  source for LIBOR / SWAP  rates  which
Union  Planters  Corporation  and most  well  respected  financial  institutions
subscribe  to. Type  USSWAP<GO>  to see the US Government  Composite  rate
screen.

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7.        
Default  Rate  and  Late  Charge.  After  maturity  (by  acceleration  or
otherwise) the unpaid balance (both principal and unpaid pre-maturity  interest)
shall bear  interest at a Default  Rate equal to four percent (4%) over the rate
of interest in effect  immediately prior to maturity.  If any payment under this
Promissory  Note is not received by the holder  hereof  within ten (10) calendar
days after the  payment  is due,  Makers  will pay to the  holder  hereof a late
charge of the lesser of Five  Percent  (5%) of the  amount  due or One  Thousand
Dollars and No Cents ($1,000.00).

8.        
Notices. All notices to be given pursuant to this Promissory Note will be
sufficient if given by personal  service,  or by guaranteed  overnight  delivery
service,  or by postage  prepaid  mailing by certified or  registered  mail with
return receipt  requested,  to the parties as set forth below,  or to such other
address as a party may request by notice  given  pursuant to this  Section.  Any
time period  provided in the giving of any notice  hereunder shall commence upon
the date of personal service, the day after delivery to the guaranteed overnight
delivery  service,  or two (2) days after mailing  certified or registered mail.
However, any failure to give notice in accordance with the terms of this Section
will not  invalidate  such  notice if such  notice  was in fact in  writing  and
actually received by the party to whom it was directed.

| | MAKERS: | Bioanalytical Systems, Inc.
2701 Kent Avenue
West Lafayette, Indiana 47906
Attention: Douglas P. Wieten
BAS Evansville, Inc.
10424 Middle Mt. Vernon Road
Mount Vernon, Indiana 47620
Attention:  Michael P. Sylvon, Ph.D.
| | ------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| | LENDER: | UNION PLANTERS BANK, N.A.
437 South Street
P.O. Box 780
Lafayette, IN 47902-0780
Attention:  Daniel R. House                                                                                                              

9.        
Governing  Law.  This  Promissory  Note and all  rights  and  obligations
hereunder, including matters of construction,  validity and performance, will be
governed by the Uniform  Commercial Code and other  applicable laws of the State
of Indiana.  Whenever  possible each provision of this  Promissory  Note will be
interpreted in such a manner as to be effective and valid upon  applicable  law,
but if any  provision of this  Promissory  Note will be prohibited by or invalid
under  applicable law, such provision will be ineffective  only to the extent of
such  prohibition  without  invalidating  the remainder of such provision or the
remaining provisions of this Promissory Note.

10.        
Evidence of Credit  Extensions.  Payee shall record the date,  amount and
maturity  of each  Advance  and the  amount of each  payment  of  principal  and
interest made by Maker with respect  thereto,  in its records,  and Payees
record shall be  conclusive  absent  manifest  error.  Any statement of Payee to
Maker setting  forth  Makers  account  regarding the Advances and payments
shall be  considered  true and  correct  and  binding on Maker  unless  Payee is
notified in writing of any discrepancy or exception within thirty (30) days from
the mailing by Payee to Maker of any such monthly statement. Notwithstanding the
foregoing,  the failure to make, or an error in making,  a notation with respect
to any  Advance  shall not limit or  otherwise  affect the  obligation  of Maker
hereunder or under this Promissory Note.

 5 

11.        
Setoff.  Payee shall have the right at any time to apply Payees own
debt or liability to Maker or to any other party liable on this  Promissory Note
in whole or partial  payment of this  Promissory Note or other present or future
liabilities  of Maker to Payee,  without  any  requirement  of mutual  maturity.

12.        
Related  Documents.  This  Promissory  Note is made  pursuant to the Loan
Agreement  and is  secured  by the real  estate  mortgages  and  other  security
instruments  therein  referred to. The terms,  conditions and definitions of the
Loan Agreement are  incorporated in this  Promissory Note by this reference.  If
any  installment  due on this  Promissory Note is not paid when due, or if there
should be an Event of Default under the Loan Agreement which is not cured within
the grace period (if any)  allowed for the cure  thereof,  the unpaid  principal
balance  hereof  together with interest  accrued  thereon,  at the option of the
holder  hereof,  immediately  become due and payable  without  notice or demand.

The real estate  mortgages  and other  security  instruments  referred to in the
preceding paragraph may also secure the payment of other obligations of Maker. A
default in the  payment of any of such other  obligations  after any  applicable
notice  and  periods  of grace or cure  shall  constitute  a default  hereunder.
Nothing  herein  shall in any way lessen or impair the rights of the holder with
respect to this Promissory Note. This Promissory Note and the other  obligations
referred  to above  shall  remain  separate  obligations  of Maker  and shall be
separately  enforceable  according  to their  respective  terms.  The holder may
institute  separate  proceedings with respect to each  simultaneously or in such
order and such times as the holder may elect.  The  pendency of any  proceedings
with respect to this  Promissory Note or other  obligation  shall not be grounds
for the abatement or for hindering,  delaying or preventing any proceedings with
respect to any other obligation.  Default under each shall constitute a separate
cause of action and the institution of proceedings  upon one, but not all, shall
not be construed as splitting a cause of action by the holder.

13.        
Waiver.  Each endorser and any other party liable on this Promissory Note
severally  waives  demand,  presentment,  notice of dishonor  and  protest,  and
consents to any extension or  postponement  of time of its payment without limit
as to the number or period, to any  substitution,  exchange or release of all or
any part of the collateral,  to the addition of any party, and to the release or
discharge of, or suspension of any rights and remedies  against,  any person who
may be liable for the payment of this  Promissory  Note. No delay on the part of
Payee in the  exercise  of any right or remedy  shall  operate  as a waiver.  No
single or partial  exercise by Payee of any right or remedy  shall  preclude any
other  future  exercise of it or the  exercise of any other right or remedy.  No
waiver  or  indulgence  by Payee of any  default  shall be  effective  unless in
writing and signed by Payee,  nor shall a waiver on one occasion be construed as
a bar to or waiver of that right on any future occasion.

 6 

14.        
Miscellaneous.  This  Promissory  Note  shall be  binding  on  Maker  and
Makers successors, and shall inure to the benefit of Payee, its successors
and assigns.  Any reference to Payee shall include any holder of this Promissory
Note.  Section  headings are for  convenience  of  reference  only and shall not
affect the  interpretation  of this Promissory  Note. This Promissory  Note, the
Loan Agreement and the Instruments embody the entire agreement between Maker and
Payee  regarding  the terms of the loan  evidenced by this  Promissory  Note and
supersede  all  oral  statements  and  prior  writings  relating  to that  Loan.

15.        
WAIVER OF JURY TRIAL. MAKER, AFTER CONSULTING OR HAVING HAD
THE   OPPORTUNITY  TO  CONSULT  WITH  COUNSEL,   KNOWINGLY,   VOLUNTARILY,   AND
INTENTIONALLY  WAIVES ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY IN ANY LITIGATION
BASED UPON OR ARISING OUT OF THIS PROMISSORY NOTE, THE INSTRUMENTS OR ANY OF THE
TRANSACTIONS  CONTEMPLATED  BY THE LOAN  AGREEMENT  OR ANY  COURSE  OF  CONDUCT,
DEALING,  STATEMENTS,  WHETHER ORAL OR WRITTEN, OR ACTIONS OF PAYEE. MAKER SHALL
NOT SEEK TO CONSOLIDATE,  BY  COUNTERCLAIM  OR OTHERWISE,  ANY ACTION IN WHICH A
JURY  TRIAL  CANNOT BE OR HAS NOT BEEN  WAIVED.  THESE  PROVISIONS  SHALL NOT BE
DEEMED TO HAVE BEEN MODIFIED IN ANY RESPECT OR RELINQUISHED BY PAYEE EXCEPT BY A
WRITTEN INSTRUMENT EXECUTED BY PAYEE.

IN WITNESS  WHEREOF,  Makers have executed this Promissory Note this 29th day of
October, 2002.

| | BIOANALYTICAL SYSTEMS. INC.
By:  /s/ Peter T. Kissinger
Peter T. Kissinger, Ph.D.,
Chairman and Chief Executive Officer
BAS EVANSVILLE, INC.
By:  /s/ Peter T. Kissinger
Peter T. Kissinger, Ph.D.,
President
| | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

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