Exhibit 10.1

                       SECURED CONVERTIBLE REVOLVING NOTE

$925,000                                                Dated: November 14, 2002
                                                     Maturity Date:  May 1, 2003

      FOR VALUE RECEIVED, PharmaKinetics Laboratories, Inc., a Maryland
corporation ("Borrower"), hereby promises to pay to the order of Bioanalytical
Systems, Inc., an Indiana corporation, or its successors or permitted assigns
("Lender"), at the address specified in Section 11 herein, or at such other
place as Lender may direct, the principal amount (the "Principal Amount") of
Nine Hundred Twenty-Five Thousand United States Dollars ($925,000) (or such
lesser amount as shall equal the aggregate unpaid principal amount of the Loans
(as defined below) made by the Lender to the Borrower hereunder) together with
interest thereon at the rate of interest and in the manner set forth herein.

      1. Loans. This Secured Revolving Note (this "Note") evidences certain
advances and extensions of credit made prior to the date hereof and, subject to
the terms and conditions of this Note, and subject to the availability of cash
for such purposes and the restrictions set forth in any agreement between Lender
and its lenders, to be made after the date hereof by Lender, in Lender's sole
discretion, in favor of Borrower (the "Loans"). The aggregate principal amount
of the Loans shall not exceed the Principal Amount. The Loans shall be evidenced
by this Note and this Note shall supersede and replace the promissory notes of
Borrower in favor of Lender dated June 13, 2002, June 26, 2002, July 25, 2002,
August 9, 2002, September 30, 2002, October 4, 2002, October 31, 2002 and
October 31, 2002. Borrower acknowledges that all Loans advanced prior to the
date hereof are accurately recorded on the schedule attached hereto (the "Loan
Schedule") and authorizes the Lender to record on the Loan Schedule the date and
amount of each additional advance hereunder and the date and amount of each
repayment of principal, provided, however, that any failure by Lender to record
any such information shall not relieve Borrower of its obligation to repay the
outstanding principal amount of such advances, accrued interest thereon, and any
other amount payable with respect thereto in accordance with the terms of this
Note.

      2. Payments. The entire unpaid principal balance of this Note, and all
accrued and unpaid interest thereon and all fees and charges incurred in
connection therewith, shall be due and payable on May 1, 2003 (the "Maturity
Date").

      3. Interest. The outstanding principal balance of this Note shall bear
interest at a rate equal to eight percent (8%) per annum. Interest shall be due
and payable for the exact number of days principal is outstanding and shall be
calculated on the basis of a three hundred sixty (360) day year. If any payment
required by this Note is not made within five (5) days of the date such payment
is due, this Note shall bear interest (computed and adjusted in the same manner,
and with the same effect, as interest hereon prior to maturity) after the due
date at a rate per annum

<PAGE>

equal to two percent (2%) above the rate that would otherwise be in effect,
until paid, and whether before or after the entry of judgment hereon.

     4. Prepayment. Borrower may prepay all or any portion of the unpaid balance
of this Note, without premium or penalty, at any time and from time to time;
provided, however, that all sums received by Lender in respect of this Note
shall be applied by Lender in the following order (i) to any costs of collection
and expenses reimbursable by Borrower to Lender, (ii) to the payment of
interest, if any, due on the outstanding balance of this Note or so much thereof
as shall from time to time remain unpaid, and (iii) to reduce the outstanding
principal balance of this Note.

5. Conversion.

     (a) The Lender may, at Lender's option, at any time, and from time to time,
     prior to payment in full of this Note, convert the outstanding unpaid
     balance of this Note and any interest accrued pursuant to paragraph 3 above
     but unpaid (the "Conversion Amount"), in whole or in part (but only into
     full shares), into fully paid and non-assessable shares of the common
     stock, $.005 par value of Borrower's common shares (the "Common Shares"),
     at a price of $0.1585 per Common Share, subject to adjustment pursuant to
     paragraph 5(b) hereof (the "Conversion Rate"). In order to exercise this
     conversion right, the Lender must send written notice of the conversion to
     Borrower at least 2 days prior to the specified conversion date (a
     "Conversion Notice"). On the conversion date (or as soon thereafter as is
     reasonably practicable), Borrower shall issue to Lender a share certificate
     for the Common Shares acquired upon conversion.

     (b) The Conversion Rate shall be subject to adjustment: (i) if Borrower at
     any time subdivides (by any stock split, stock dividend, recapitalization
     or otherwise) one or more classes of its outstanding Common Shares into a
     greater number of shares, in which case the Conversion Rate in effect
     immediately prior to the subdivision will be proportionately reduced; (ii)
     if Borrower at any time combines (by reverse stock split or otherwise) one
     or more classes of its outstanding Common Shares into a smaller number of
     shares, in which case the Conversion Rate in effect immediately prior to
     that combination will be proportionately increased; or (iii) upon the
     issuance by Borrower of Common Shares, or of rights, options, warrants, or
     other securities convertible into Common Shares, at a price per share that
     is less than the Conversion Rate, in which case the Conversion Rate shall
     be adjusted so that it is equal to such per share price.

     (c) Notwithstanding any other provisions of this Section 5 to the contrary,
     the conversion rights of Lender shall be subject to compliance with all
     applicable federal and state securities laws, and Lender agrees to execute
     all required agreements and documents required by Borrower to establish
     compliance with such laws.

     (d) Borrower shall at all times reserve and keep available and free of
     preemptive rights out of its authorized but unissued Common Shares, solely
     for the purpose of issuance upon conversion of the Note, that number of
     Common Shares as shall from time


                                      -2-
<PAGE>

     to time be sufficient to effect the conversion of the Note, and if at any
     time the number of authorized but unissued Common Shares shall not be
     sufficient to effect the conversion of the Note, Borrower shall take the
     corporate action necessary to increase the number of its authorized Common
     Shares to a number sufficient for this purpose.

     (e) Notwithstanding anything in this Note to the contrary, the rights
     granted to Lender by this Section 5 (the "Conversion Rights") shall not
     become effective unless and until the registered owners of 100% of the
     Class B Convertible Preferred Stock of the Borrower (the "Preferred
     Holders") have delivered written notice to the Borrower of the waiver of
     the Preferred Holders of the rights granted to the Preferred Holders
     pursuant to section 5 of the PharmaKinetics Laboratories, Inc. Articles
     Supplementary dated April 17, 2000 in connection with the Conversion
     Rights.

      6. Method of Payment. All payments of principal and interest hereunder
shall be paid by Borrower in United States Dollars by wire transfer of
immediately available funds or in such other manner or at such other place as
Lender shall direct.

      7. Events of Default. Each of the following constitutes an "Event of
Default" hereunder:

          (a) If the entire outstanding principal balance on this Note, together
     with any accrued and unpaid interest thereon, is not paid within five (5)
     days after the Maturity Date;

          (b) If a default occurs under the Security Agreement (as defined
     below) or the Guaranty (as defined below) and is not cured within thirty
     (30) days of the occurrence thereof; or

          (c) If Borrower applies for, consents to or acquiesces in the
     appointment of a trustee, receiver or other custodian for Borrower or any
     property or assets of Borrower, or makes a general assignment for the
     benefit of creditors; or, in the absence of such application, consent or
     acquiescence, a trustee, receiver or other custodian is appointed for
     Borrower or for a substantial part of the property or assets of Borrower
     and is not discharged within sixty (60) days; or any bankruptcy,
     reorganization, debt arrangement, or other case or proceeding under any
     bankruptcy or insolvency law, or any dissolution or liquidation proceeding,
     is commenced in respect of Borrower, and if such case or proceeding is not
     commenced by Borrower, it is consented to or acquiesced in by Borrower or
     if such case or proceeding is not vacated, stayed or dismissed within sixty
     (60) days of such commencement.

     8. Remedies Upon an Event of Default. If an Event of Default under Section
7(c) shall occur and be continuing, the entire unpaid amount of this Note shall
be immediately due and payable without presentment, demand, protest or notice of
any kind, all of which Borrower expressly waives, and Lender may thereafter
exercise from time to time any rights, powers and remedies available to it under
all applicable laws or in equity. If an Event of Default under


                                      -3-
<PAGE>

Section 7(a) or Section 7(b) of this Note shall occur and be continuing, then
Lender may, at its option, exercise any one or more of the following rights and
remedies:

          (a) Lender may declare the entire unpaid amount of this Note to be
     immediately due and payable without presentment, demand, protest or notice
     of any kind, all of which Borrower expressly waives; and

          (b) Lender may exercise from time to time any rights, powers and
     remedies available to him under all applicable laws or in equity.

In addition, if any Event of Default has occurred Lender shall be entitled to
recover from Borrower all costs and expenses, including reasonable attorneys'
fees and disbursements and court costs, incurred in enforcing its rights
hereunder. The rights and remedies of Lender stated herein are cumulative to and
not exclusive of any rights or remedies otherwise available to Lender.

     9. Security Interest. This Note and any extensions or renewals hereof,
shall be secured by a Security Agreement dated of even date herewith (the
"Security Agreement") which has been duly executed in favor of and delivered by
Borrower to Lender and is entitled to the benefit of a Guaranty made on the date
hereof (the "Guaranty") by PKLB Limited Partnership, a Maryland limited
partnership, in favor of Lender. Reference is made to the Security Agreement and
the Guaranty for a description of the nature and extent of the security, rights,
duties and obligations of Borrower and the Guarantor and the rights of Lender.

     10. Usury Laws. It is the intention of Borrower and Lender to conform
strictly to all applicable usury laws now or hereafter in force, and any
interest payable under this Note shall be subject to reduction to an amount
which is the maximum legal amount allowed under the applicable usury laws as now
or hereafter construed by the courts having jurisdiction over such matters. The
aggregate of all interest (whether designated as interest, service charges,
points or otherwise) contracted for, chargeable, or receivable under this Note
shall under no circumstances exceed the maximum legal rate upon the unpaid
principal balance of this Note remaining unpaid from time to time. If such
interest does exceed the maximum legal rate, it shall be deemed a mistake and
such excess shall be canceled automatically and, if theretofore paid, rebated to
Borrower or credited on the principal amount of this Note, or if this Note has
been repaid, then such excess shall be rebated to Borrower.

     11. Assignability. This Note and the rights and obligations hereunder shall
not be assignable or transferable, by operation of law or otherwise; provided,
however, this Note may be assigned in whole or in part by Lender to any
individual, corporation, partnership, limited partnership, limited liability
company or other entity controlled by Lender in Lender's sole and absolute
discretion and without the consent of Borrower.

     12. Notices. All notices and other communications given or made pursuant
hereto shall be in writing and shall be deemed to have been duly given or made
as of the date delivered or sent if delivered personally or sent by telecopier
or by prepaid overnight carrier to the parties


                                      -4-
<PAGE>

at the following addresses (or at such other addresses as shall be specified by
the parties by like notice):

                  if to Lender:

                           Bioanalytical Systems, Inc.
                           2701 Kent Avenue
                           Purdue Research Park
                           West Lafayette, Indiana 47906
                           Attention: Peter T. Kissinger, Ph.D.
                           Facsimile: (765) 497-1102

                           with a copy to:

                           Ice Miller
                           One American Square Box 82001
                           Indianapolis, Indiana 46282-0002
                           Attention: Stephen J. Hackman, Esq.
                           Facsimile: (317) 236-2219

                  If to Borrower:

                           PharmaKinetics Laboratories, Inc.
                           302 West Fayette Street
                           Baltimore, Maryland 21201
                           Attention: James M. Wilkinson, II, Ph.D.
                           Facsimile: (410) 385-1957

                           with a copy to:

                           Strasburger & Price, LLP
                           901 Main Street
                           Dallas, Texas 75202-3794
                           Attention: David K. Meyercord, Esq.
                           Facsimile: (214) 651-4330

13. Miscellaneous.

     (a) This Note shall in all respects be governed by and construed in
accordance with the laws of the State of Indiana without regard to conflicts of
law principles.

     (b) Borrower waives presentment, notice and demand, notice of protest,
notice of demand and dishonor, and notice of nonpayment of this Note.


                                      -5-
<PAGE>

     (c) Lender shall not (by act, delay, omission or otherwise) be deemed to
have waived any of its rights or remedies hereunder, or any provision hereof,
unless such waiver is in writing signed by Lender, and any such waiver shall be
effective only to the extent specifically set forth therein. A waiver by Lender
of any right or remedy under this Note on any one occasion shall not be
construed as a bar to or waiver of any such right or remedy which Lender would
otherwise have had on any future occasion.

     (d) Wherever possible, each provision of this Note which has been
prohibited by or held invalid under applicable law shall be ineffective to the
extent of such prohibition or invalidity, but such prohibition or invalidity
shall not invalidate the remainder of such provision or the remaining provisions
of this Note.

     (e) Wherever in this Note reference is made to Borrower or Lender, such
reference shall be deemed to include, as applicable, a reference to their
respective successors and assigns, legatees, heirs, executors, administrators
and legal representatives, as applicable, and, in the case of Lender, any future
Lender of this Note, in any case as permitted by this Note. Subject to Section
11, the provisions of this Note shall be binding upon and shall inure to the
benefit of such successors, assigns, Lenders, legatees, heirs, executors,
administrators and legal representatives, as applicable.


                                      -6-
<PAGE>

     IN WITNESS WHEREOF, Borrower has executed and delivered this Note as of the
day and year first above written.

                                        PHARMAKINETICS LABORATORIES, INC.


                                        By: /s/ James M. Wilkinson II, Ph.D.
                                           -------------------------------------

                                        Printed: James M. Wilkinson II, Ph.D.
                                                --------------------------------

                                        Its:     President & CEO
                                            ------------------------------------

Acknowledged:

BIOANALYTICAL SYSTEMS, INC

By: /s/ Douglas P. Wieten
   --------------------------------

Printed: Douglas P. Wieten
        ---------------------------

Its:  CFO
     ------------------------------


                                      -7-
<PAGE>

            SCHEDULE OF AMOUNTS ADVANCED AND PAYMENTS OR PREPAYMENTS

<TABLE>
<CAPTION>
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                                                              Principal Paid or    Amount of Unpaid
        Date           Amount of Advance      Interest Rate       Prepaid         Principal Balance   Notation Made By
------------------------------------------------------------------------------------------------------------------------
<S>                      <C>                       <C>             <C>                <C>             <C>
June 13, 2002            $100,000.00               8%              $0.00              $100,000.00
------------------------------------------------------------------------------------------------------------------------
June 26, 2002            $100,000.00               8%              $0.00              $200,000.00
------------------------------------------------------------------------------------------------------------------------
July 25, 2002            $100,000.00               8%              $0.00              $300,000.00
------------------------------------------------------------------------------------------------------------------------
August 9, 2002           $ 50,000.00               8%              $0.00              $350,000.00
------------------------------------------------------------------------------------------------------------------------
September 30, 2002       $ 57,857.61               8%              $0.00              $407,857.61
------------------------------------------------------------------------------------------------------------------------
October 4, 2002          $ 15,000.00               8%              $0.00              $422,857.61
------------------------------------------------------------------------------------------------------------------------
October 31, 2002         $ 15,608.08               8%              $0.00              $438,465.69
------------------------------------------------------------------------------------------------------------------------
October 31, 2002         $130,000.00               8%              $0.00              $568,465.69
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</TABLE>


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<PAGE>

            SCHEDULE OF AMOUNTS ADVANCED AND PAYMENTS OR PREPAYMENTS

<TABLE>
<CAPTION>
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                                                              Principal Paid or    Amount of Unpaid
        Date           Amount of Advance      Interest Rate       Prepaid         Principal Balance   Notation Made By
------------------------------------------------------------------------------------------------------------------------
<S>                      <C>                       <C>             <C>                <C>             <C>

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</TABLE>


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<PAGE>

            SCHEDULE OF AMOUNTS ADVANCED AND PAYMENTS OR PREPAYMENTS

<TABLE>
<CAPTION>
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                                                              Principal Paid or    Amount of Unpaid
        Date           Amount of Advance      Interest Rate       Prepaid         Principal Balance   Notation Made By
------------------------------------------------------------------------------------------------------------------------
<S>                      <C>                       <C>             <C>                <C>

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                                      -10-