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                                                                   EXHIBIT 10.32

                               UNLIMITED GUARANTY

      GUARANTY, dated as of February 28, 2000 by Microfluidics Corporation, a
Delaware corporation with a place of business at 30 Ossipee Road, Newton,
Massachusetts 02464 (the "Guarantor"), in favor of National Bank of Canada, a
Canadian chartered bank with an office at One Federal Street, Boston,
Massachusetts 02110 (the "Lender"). In consideration of the Lender's giving, in
its discretion, time, credit or banking facilities or accommodations to MFIC
Corporation (together with its successors, the "Borrower"), the Guarantor agrees
as follows:

      1. GUARANTY OF PAYMENT AND PERFORMANCE. The Guarantor hereby guarantees to
the Lender the full and punctual payment when due (whether at maturity, by
acceleration or otherwise), and the performance, of all Liabilities (as defined
in that certain Revolving Credit and Term Loan Agreement of even date herewith,
as the same may be modified, amended, supplemented or restated from time to
time, the "Loan Agreement") of the Borrower to the Lender. This Guaranty is an
absolute, unconditional and continuing guaranty of the full and punctual payment
and performance of the Liabilities and not of their collectibility only and is
in no way conditioned upon any requirement that the Lender first attempt to
collect any of the Liabilities from the Borrower or resort to any security or
other means of obtaining their payment. Should the Borrower default in the
payment or performance of any of the Liabilities, the obligations of the
Guarantor hereunder shall become immediately due and payable to the Lender,
without demand or notice of any nature, all of which are expressly waived by the
Guarantor. Payments by the Guarantor hereunder may be required by the Lender on
any number of occasions.

      2. GUARANTOR'S AGREEMENT TO PAY. The Guarantor further agrees, as the
principal obligor and not as a guarantor only, to pay to the Lender, on demand,
all costs and expenses (including court costs and reasonable legal expenses)
incurred or expended by the Lender in connection with the Liabilities, this
Guaranty and the enforcement thereof, together with interest on amounts
recoverable under this Guaranty from the time such amounts become due until
payment at the default rate provided for in the Loan Agreement.

      3. UNLIMITED GUARANTY. The liability of the Guarantor hereunder shall be
unlimited.

      4. WAIVERS BY GUARANTOR; BANK'S FREEDOM TO ACT. The Guarantor agrees that
the Liabilities will be paid and performed strictly in accordance with their
respective terms regardless of any law, regulation or order now or hereafter in
effect in any jurisdiction affecting any of such terms or the rights of the
Lender with respect thereto. The Guarantor waives presentment, demand, protest,
notice of acceptance, notice of Liabilities incurred and all other notices of
any kind, all defenses which may be available by virtue of any valuation, stay,
moratorium law or other similar law now or hereafter in effect, any right to
require the marshalling of assets of the Borrower, and all suretyship defenses
generally. Without limiting the generality of the foregoing, the Guarantor
agrees to the provisions of any instrument evidencing, securing or otherwise
executed in connection with any Obligation and agrees that the
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obligations of the Guarantor hereunder shall not be released or discharged, in
whole or in part, or otherwise affected by (i) the failure of the Lender to
assert any claim or demand or to enforce any right or remedy against the
Borrower; (ii) any extensions or renewals of any Obligation; (iii) any
rescissions, waivers, amendments or modifications of any of the terms or
provisions of any agreement evidencing, securing or otherwise executed in
connection with any Obligation; (iv) the substitution or release of any entity
primarily or secondarily liable for any Obligation; (v) the adequacy of any
rights the Lender may have against any collateral or other means of obtaining
repayment of the Liabilities; (vi) the impairment of any collateral securing the
Liabilities, including without limitation the failure to perfect or preserve any
rights the Lender might have in such collateral or the substitution, exchange,
surrender, release, loss or destruction of any such collateral; or (vii) any
other act or omission which might in any manner or to any extent vary the risk
of the Guarantor or otherwise operate as a release or discharge of the
Guarantor, all of which may be done without notice to the Guarantor.

      5. UNENFORCEABILITY OF OBLIGATIONS AGAINST CUSTOMER. If for any reason the
Borrower has no legal existence or is under no legal obligation to discharge any
of the Liabilities, or if any of the Liabilities have become irrecoverable from
the Borrower by operation of law or for any other reason, this Guaranty shall
nevertheless be binding on the Guarantor to the same extent as if the Guarantor
at all times had been the principal obligor on all such Liabilities. In the
event that acceleration of the time for payment of the Liabilities is stayed
upon the insolvency, bankruptcy or reorganization of the Borrower, or for any
other reason, all such amounts otherwise subject to acceleration under the terms
of any agreement evidencing, securing or otherwise executed in connection with
any Obligation shall be immediately due and payable by the Guarantor.

      6. SUBROGATION; SUBORDINATION. The Guarantor shall not exercise any rights
against the Borrower arising as a result of payment by the Guarantor hereunder,
by way of subrogation or otherwise, and will not prove any claim in competition
with the Lender or its affiliates in respect of any payment hereunder in
bankruptcy or insolvency proceedings of any nature; the Guarantor will not claim
any set-off or counterclaim against the Borrower in respect of any liability of
the Guarantor to the Borrower; and the Guarantor waives any benefit of and any
right to participate in any collateral which may be held by the Lender or any
such affiliate. The payment of any amounts due with respect to any indebtedness
of the Borrower now or hereafter held by the Guarantor is hereby subordinated to
the prior payment in full of the Liabilities, provided that so long as no
default in the payment or performance of the Liabilities has occurred and is
continuing, or no demand for payment of any of the Liabilities has been made
that remains unsatisfied, the Borrower may make, and the Guarantor may demand
and accept, any scheduled payments of principal of and interest on such
subordinated indebtedness in the amounts, at the rates and on the dates
specified in such instruments, securities or other writings as shall evidence
such subordinated indebtedness. The Guarantor agrees that after the occurrence
of any default in the payment or performance of the Liabilities, the Guarantor
will not demand, sue for or otherwise attempt to collect any such indebtedness
of the Borrower to the Guarantor until the Liabilities shall have been paid in
full. If, notwithstanding the foregoing sentence, the Guarantor shall collect,
enforce or receive any amounts in respect of such


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indebtedness, such amounts shall be collected, enforced and received by the
Guarantor as trustee for the Lender and be paid over to the Lender on account of
the Liabilities without affecting in any manner the liability of the Guarantor
under the other provisions of this Guaranty.

      7. SECURITY; SET-OFF. The Guarantor grants to the Lender, as security for
the full and punctual payment and performance of the Guarantor's obligations
hereunder, a continuing lien on and security interest in all securities or other
property belonging to the Guarantor now or hereafter held by the Lender and in
all deposits (general or special, time or demand, provisional or final) and
other sums credited by or due from the Lender to the Guarantor or subject to
withdrawal by the Guarantor; and regardless of the adequacy of any collateral or
other means of obtaining repayment of the Liabilities, the Lender is hereby
authorized at any time and from time to time, without notice to the Guarantor
(any such notice being expressly waived by the Guarantor) and to the fullest
extent permitted by law, to set off and apply such deposits and other sums
against the obligations of the Guarantor under this Guaranty, whether or not the
Lender shall have made any demand under this Guaranty and although such
obligations may be contingent or unmatured.

      8. FURTHER ASSURANCES. The Guarantor agrees that it will, from time to
time at the reasonable request of the Lender, provide to the Lender its most
recent audited and unaudited balance sheets and related statements of income and
changes in financial condition (prepared on a consolidated basis with the
Borrower or Guarantor's subsidiaries, if any) and such other information
relating to the business and affairs of the Guarantor as the Lender may
reasonably request. The Guarantor also agrees to do all such things and execute
all such documents, including financing statements, as the Lender may consider
necessary or desirable to give full effect to this Guaranty and to perfect and
preserve the rights and powers of the Lender hereunder.

      9. TERMINATION; REINSTATEMENT. This Guaranty shall remain in full force
and effect until the Lender is given written notice of the Guarantor's intention
to discontinue this Guaranty, notwithstanding any intermediate or temporary
payment or settlement of the whole or any part of the Liabilities. No such
notice shall be effective unless received and acknowledged by an officer of the
Lender at its head office or at the branch of the Lender where this Guaranty is
given. No such notice shall affect any rights of the Lender or of any affiliate
hereunder including, without limitation, the rights set forth in Sections 4 and
6, with respect to Liabilities incurred prior to the receipt of such notice or
Liabilities incurred pursuant to any contract or commitment in existence prior
to such receipt, and all checks, drafts, notes, instruments (negotiable or
otherwise) and writings made by or for the account of the Borrower and drawn on
the Lender or any of its agents purporting to be dated on or before the date of
receipt of such notice, although presented to and paid or accepted by the Lender
after that date, shall form part of the Liabilities. This Guaranty shall
continue to be effective or be reinstated, notwithstanding any such notice, if
at any time any payment made or value received with respect to an Obligation is
rescinded or must otherwise be returned by the Lender upon the insolvency,
bankruptcy or reorganization of the Borrower, or otherwise, all as though such
payment had not been made or value received.


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      10. SUCCESSORS AND ASSIGNS. This Guaranty shall be binding upon the
Guarantor, its successors and assigns, and shall inure to the benefit of and be
enforceable by the Lender and its successors, transferees and assigns. Without
limiting the generality of the foregoing sentence and as permitted in the Loan
Agreement, the Lender may assign or otherwise transfer any agreement or any note
held by it evidencing, securing or otherwise executed in connection with the
Liabilities, or sell participations in any interest therein, to any other person
or entity, and such other person or entity shall thereupon become vested, to the
extent set forth in the agreement evidencing such assignment, transfer or
participation, with all the rights in respect thereof granted to the Lender
herein.

      11. AMENDMENTS AND WAIVERS. No amendment or waiver of any provision of
this Guaranty nor consent to any departure by the Guarantor therefrom shall be
effective unless the same shall be in writing and signed by the Lender. No
failure on the part of the Lender to exercise, and no delay in exercising, any
right hereunder shall operate as a waiver thereof; nor shall any single or
partial exercise of any right hereunder preclude any other or further exercise
thereof or the exercise of any other right.

      12. NOTICES. All notices and other communications called for hereunder
shall be made in accordance with and shall be deemed to have been duly made or
given when delivered in accordance with the provisions of Section 17 of the Loan
Agreement.

      13. GOVERNING LAW; CONSENT TO JURISDICTION. This Guaranty is intended to
take effect as a sealed instrument and shall be governed by, and construed in
accordance with, the laws of The Commonwealth of Massachusetts. The Guarantor
agrees that any suit for the enforcement of this Guaranty may be brought in the
courts of The Commonwealth of Massachusetts or any Federal Court sitting therein
and consents to the non-exclusive jurisdiction of such court and to service of
process in any such suit being made upon the Guarantor by mail at the address
specified in Section 12 hereof. The Guarantor hereby waives any objection that
it may now or hereafter have to the venue of any such suit or any such court or
that such suit was brought in an inconvenient court.

      14. MISCELLANEOUS. This Guaranty constitutes the entire agreement of the
Guarantor with respect to the matters set forth herein. The rights and remedies
herein provided are cumulative and not exclusive of any remedies provided by law
or any other agreement, and this Guaranty shall be in addition to any other
guaranty of the Liabilities. The invalidity or unenforceability of any one or
more sections of this Guaranty shall not affect the validity or enforceability
of its remaining provisions. Captions are for the ease of reference only and
shall not affect the meaning of the relevant provisions. The meanings of all
defined terms used in this Guaranty shall be equally applicable to the singular
and plural forms of the terms defined.

      15. WAIVER OF JURY TRIAL AND CERTAIN DAMAGE CLAIMS. THE GUARANTOR HEREBY
WAIVES ITS RIGHT TO A JURY TRIAL WITH RESPECT TO ANY ACTION OR CLAIM ARISING OUT
OF ANY DISPUTE IN CONNECTION WITH


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THIS AGREEMENT OR ANY OTHER OF THE LOAN DOCUMENTS TO WHICH THE GUARANTOR IS A
PARTY, ANY RIGHTS OR OBLIGATIONS HEREUNDER OR THEREUNDER OR THE PERFORMANCE OF
SUCH RIGHTS AND OBLIGATIONS. EXCEPT TO THE EXTENT EXPRESSLY PROHIBITED BY LAW,
THE GUARANTOR HEREBY WAIVES ANY RIGHT IT MAY HAVE TO CLAIM OR RECOVER AGAINST
NATIONAL BANK OF CANADA (AND NOT ITS SUCCESSORS AND ASSIGNS) IN ANY LITIGATION
REFERRED TO IN THE PRECEDING SENTENCE ANY SPECIAL, EXEMPLARY, PUNITIVE OR
CONSEQUENTIAL DAMAGES OR ANY DAMAGES OTHER THAN, OR IN ADDITION TO, ACTUAL
DAMAGES. THE GUARANTOR (A) CERTIFIES THAT NO REPRESENTATIVE, LENDER OR ATTORNEY
OF THE LENDER HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT THE LENDER WOULD
NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVERS AND (B)
ACKNOWLEDGES THAT THE LENDER HAS BEEN INDUCED TO ENTER INTO THIS AGREEMENT AND
THE OTHER LOAN DOCUMENTS IT IS PARTY BY, AMONG OTHER THINGS, THE WAIVERS AND
CERTIFICATIONS CONTAINED HEREIN.

      IN WITNESS WHEREOF, the Guarantor has executed and delivered this
Guaranty, or caused this Guaranty to be executed and delivered by its duly
authorized officer, as of the date appearing on page one.

WITNESS:                            GUARANTOR:

                                    MICROFLUIDICS CORPORATION


                                    By: /s/ Irwin J. Gruverman
------------------------------          --------------------------------

                                    Name: Irwin J. Gruverman

                                    Title: Chairman and CEO


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