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                                                                   Exhibit 10.46

                                BIO-PLEXUS, INC.

                            SECURED CONVERTIBLE NOTE

         THIS NOTE HAS BEEN ISSUED WITH ORIGINAL ISSUE DISCOUNT. FOR INFORMATION
REGARDING THE AMOUNT OF ORIGINAL ISSUE DISCOUNT, THE ISSUE PRICE, ISSUE DATE,
THE YIELD TO MATURITY OF THE SECURITY, AND, FOR PURPOSES OF TREAS. REG. SEC.
1.1275-4(B)(3)(II), THE COMPARABLE YIELD AND PROJECTED PAYMENT SCHEDULE, CONTACT
THE COMPANY AT 129 RESERVOIR ROAD, VERNON, CT 06066.

         THE TRANSFER OF THIS NOTE IS RESTRICTED BY AND PURSUANT TO THE
CONVERTIBLE NOTE PURCHASE AGREEMENT DATED AS OF APRIL 28, 2000, A COPY OF WHICH
IS ON FILE AT THE OFFICES OF THE COMPANY.

         THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR
THE SECURITIES LAWS OF ANY STATE AND MAY NOT BE SOLD OR OTHERWISE DISPOSED OF
EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND
APPLICABLE STATE SECURITIES LAWS OR AN APPLICABLE EXEMPTION TO THE REGISTRATION
REQUIREMENTS OF SUCH ACT OR SUCH LAWS.

No. R-                                                            April 28, 2000
      ___

__________________


                  FOR VALUE RECEIVED, the undersigned, BIO-PLEXUS, INC. (herein
called the "Company"), a corporation organized and existing under the laws of
the State of Connecticut, hereby unconditionally promises to pay to the order of
_____________, or registered assigns, the sum of _____________ DOLLARS ($
__________) plus the amount accreted on such sum at the Accretion Rate in lawful
money of the United status of America and in immediately available funds on
April __, 2005 (the "Maturity Date"). Defined terms used herein but not
otherwise defined shall have the meanings ascribed to them in the Convertible
Note Purchase Agreement, dated as of the date hereof, by and among the Company,
the Purchasers listed on Exhibit A thereto, and Appaloosa Management, L.P., as
Collateral Agent (the "Note Purchase Agreement") This Note shall not bear any
interest, except that if any amount payable under the Note Purchase Agreement is
not paid when due, then the overdue amount shall bear interest at a rate of 15%
per annum compounded semi-annually (to the extent payment of such interest shall
be legally enforceable), which interest shall accrue from the date such overdue
amount was due to the date of payment of such amount. All such interest shall be
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payable on demand. This Note is also subject to optional and mandatory
prepayments from time to time as specified in the Note Purchase Agreement, but
not otherwise.

                  Payments of principal of, interest on and any Premium (as
defined below) with respect to this Note are to be made at the account/address
as the holder of this Note shall have designated by written notice to the
Company. "Premium" shall mean any amount (other than principal or interest) due
in respect of the Notes pursuant to the Note Purchase Agreement.

                  This Note is one of the Notes issued pursuant to the Note
Purchase Agreement. Each holder of this Note will be deemed, by its acceptance
hereof, to have made the representations set forth in Section 3 of the Note
Purchase Agreement and to have agreed to be bound by the restrictions on
transfer set forth in Section 12.11 of the Note Purchase Agreement.

                  This Note is a registered note and, as provided in the Note
Purchase Agreement, upon surrender of this Note for registration of transfer,
duly endorsed, or accompanied by a written instrument of transfer duly executed,
by the registered holder hereof or such holder's attorney duly authorized in
writing, a new Note for a like principal amount will be issued to, and
registered in the name of, the transferee. Prior to due presentment for
registration of transfer, the Company may treat the person in whose name this
Note is registered as the owner hereof for the purpose of receiving payment and
for all other purposes, and the Company will not be affected by any notice to
the contrary or held liable for allocations of income, losses, gains, deductions
or credits, which are made in good faith to such registered holder.

                  This Note is secured and guaranteed as provided in the
Transaction Documents. Reference is made to the Transaction Documents for a
description of the assets in which a security interest has been granted, the
nature and extent of the security and the guarantees, the terms and conditions
upon which the security interests and each guarantee were granted and the rights
of the holder of this Note in respect thereof.

                  If an Event of Default occurs, all unpaid amounts on this Note
shall become, or may be declared to be, immediately due and payable, all as
provided in the Note Purchase Agreement.

                  THE COMPANY HEREBY WAIVES ANY RIGHT IT MAY HAVE TO A TRIAL BY
JURY IN RESPECT OF ANY ACTION, PROCEEDING OR LITIGATION DIRECTLY OR INDIRECTLY
ARISING OUT OF, UNDER OR IN CONNECTION WITH, THIS NOTE, THE NOTE PURCHASE
AGREEMENT, OR ANY OTHER TRANSACTION DOCUMENTS.

                  THIS NOTE SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE WITH,
AND THE RIGHTS OF THE PARTIES SHALL BE GOVERNED BY, THE LAW OF THE STATE OF NEW
YORK EXCLUDING CHOICE-OF-LAW PRINCIPLES OF THE LAW OF SUCH STATE THAT WOULD
REQUIRE THE APPLICATION OF THE LAWS OF A JURISDICTION OTHER THAN SUCH STATE.

                  ALL PARTIES NOW AND HEREAFTER LIABLE WITH RESPECT TO THIS
NOTE, WHETHER MAKER, PRINCIPAL, SURETY, GUARANTOR, ENDORSER OR OTHERWISE, HEREBY
WAIVE PRESENTMENT, DEMAND, PROTEST AND ALL OTHER NOTICES OF ANY KIND.


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                  IF ANY ACTION, PROCEEDING OR LITIGATION SHALL BE BROUGHT BY
THE HOLDER OF THIS NOTE IN ORDER TO ENFORCE ANY RIGHT OR REMEDY UNDER THIS NOTE,
THE COMPANY HEREBY CONSENTS AND WILL SUBMIT, AND WILL CAUSE EACH OF ITS
SUBSIDIARIES TO SUBMIT, TO THE JURISDICTION OF ANY STATE OR FEDERAL COURT OF
COMPETENT JURISDICTION SITTING WITHIN THE AREA COMPRISING THE SOUTHERN DISTRICT
OF NEW YORK. THE COMPANY HEREBY IRREVOCABLY WAIVES ANY OBJECTION, INCLUDING, BUT
NOT LIMITED TO, ANY OBJECTION TO THE LAYING OF VENUE OR BASED ON THE GROUNDS OF
FORUM NON CONVENIENS, WHICH IT MAY NOW OR HEREAFTER HAVE TO THE BRINGING OF ANY
SUCH ACTION, PROCEEDING OR LITIGATION IN SUCH JURISDICTION.

                                  [END OF PAGE]

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                                        BIO-PLEXUS, INC.



                                        By:
                                           ----------------------------------
                                           Name:
                                           Title:


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