Exhibit 10.42
                                                                   -------------

                              EMPLOYMENT AGREEMENT
                              --------------------

               This EMPLOYMENT AGREEMENT (the "Employment Agreement") is made
effective this ___ day of May, 2001, by and between HemaSure Inc., a Delaware
corporation, (the "Company"), and John F. McGuire, III ("Executive").

                              W I T N E S S E T H:

               WHEREAS, Executive has provided valuable services to the Company
as its President and Chief Executive Officer; and

               WHEREAS, pursuant to a certain Asset Purchase Agreement, dated as
of February 3, 2001 and amended on April 2, 2001 (the "Purchase Agreement"), the
Company intends to sell substantially all of its non-cash assets (the "Asset
Sale") to Whatman BioScience Inc., a Massachusetts corporation ("Whatman"); and

               WHEREAS, in connection with the Asset Sale, Whatman will retain
and employ substantially all of the employees associated with the Company's
business, including Executive; and

               WHEREAS, Executive and the Company are parties to that certain
Employment Agreement, dated as of April 1, 1997 (the "Prior Employment
Agreement"); and

               WHEREAS, Executive and the Company are parties to that certain
Senior Management Retention Agreement, dated as of December 7, 1998 (the
"Retention Agreement"); and

               WHEREAS, the Company desires to retain the services of Executive
for a certain period of time following the close of the Asset Sale to provide
for the orderly


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transition of the Company's business; and

               WHEREAS, the Company and Executive desire to terminate the
Retention Agreement.

               NOW, THEREFORE, in consideration of the promises and the mutual
covenants of the parties hereinafter set forth, and for other good and valuable
consideration, the sufficiency of which is hereby irrevocably acknowledged, it
is hereby agreed as follows:

        1.      Duties.
                ------

                As of the Effective Date and during the Term, Executive shall be
employed by the Company as a Special Assistant and shall devote a reasonable
portion of his time to his duties hereunder as determined by the Board of
Directors of the Company (the "Board"); provided, however, that such time shall
in no event exceed 60 hours per month. Executive shall report directly to the
Board.

        2.      Term.
                ----

                The term of Executive's employment under this Agreement (the
"Term") will begin on the date hereof (the "Effective Date") and will terminate
(the "Termination Date") on the earlier of (i) 90 days after the effective date
of any consolidation or merger of the Company with or into any other corporation
or other entity or person, or any corporate reorganization in which the
stockholders of the Company immediately prior to such consolidation, merger or
reorganization own less than 50% of the Company's voting power immediately after
such consolidation, merger or reorganization, or (ii) the effective date of any
liquidation, dissolution or winding up of the Company (whether voluntary or
involuntary), or (iii) the 18-month anniversary of the Effective Date.

        3.      Lump Sum Payment.
                ----------------

                Within ten (10) days after the execution of this Agreement by
the parties


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hereto, the Company shall make a lump sum cash payment to Executive
in the amount of $225,000 (the "Lump Sum Payment").

        4.      Salary.
                ------

                During the Term, Executive will receive a salary at the monthly
rate of $4,166.67 ("Salary") to be paid in accordance with the Company's
standard payroll practices.

        5.      Conditional Severance Payment.
                -----------------------------

                Within ten (10) days after the Termination Date, the Company
shall pay to Executive a severance payment ("Severance Payment") equal to the
amount (if any) by which $75,000 exceeds the aggregate amount of all Salary
payments paid to Executive hereunder prior to the Termination Date.


        6.      Withholding.
                -----------

                Any payments provided for hereunder, including the Lump Sum
Payment, any Salary payments and any Severance Payment, shall be paid to
Executive net of any applicable payroll deductions and withholdings required
under federal, state or local law.

        7.      Options.
                -------

                Any options to purchase securities of the Company heretofore
issued to Executive that have vested or that shall vest during the Term shall,
upon such vesting, be exercisable at anytime during the Term and for 90 days
after the Termination Date in accordance with the terms and provisions of the
Company's 1994 Stock Option Plan or the Company's 1994 Director Option Plan and
applicable law. Any options not exercised within 90 days after the Termination
Date shall be forfeited by Executive and terminated by the Company.

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        8.      Benefits.
                --------

                Executive shall not be entitled to any compensation or other
benefits of any kind other than as set forth in this Agreement.

        9.      Prior Employment and Retention Agreements.
                -----------------------------------------

                Executive and the Company agree that each of the Prior
Employment Agreement and the Retention Agreement is hereby terminated and of no
further force and effect as of this date and neither Executive nor the Company
shall have any further rights or obligations thereunder.

        10.     Amendments.
                ----------

                This Agreement may not be altered, modified or amended except by
a written instrument signed by each of the parties hereto.

        11.     Waiver.
                ------

                Waiver by any party hereto of any breach or default by the other
party of any of the terms of this Agreement shall not operate as a waiver of any
other breach or default, whether similar to or different from the breach or
default waived.

        12.     Assignment.
                ----------

                Neither this Agreement nor any of the rights or obligations
hereunder shall be assigned or delegated by any party hereto without the prior
written consent of the other party; provided, however, that any payments and
benefits owed to Executive under this Agreement shall inure to the benefit of
Executive's heirs.

        13.     Severability.
                ------------

                In the event that any one or more of the provisions of this
Agreement shall be held to be invalid, illegal or unenforceable in any respect,
the validity, legality and enforceability of the remaining provisions contained
herein shall not be affected thereby.

        14.     Entire Agreement.
                ----------------

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                This Agreement sets forth the entire agreement and understanding
of the parties with respect to the employment of Executive by the Company. There
are no restrictions, agreements, promises, warranties, covenants or undertakings
other than those expressly set forth herein. This Agreement supersedes,
terminates and cancels all prior agreements, arrangements and understandings
between the parties, whether oral or written, with respect to the employment of
Executive or the termination thereof, including without limitation the Prior
Employment Agreement and the Retention Agreement.

        15.     Notices.
                -------

                Notices and all other communications provided for in this
Agreement shall be in writing and shall be deemed to have been duly given when
personally delivered or when mailed by United States registered mail, return
receipt requested, postage prepaid, addressed as follows:

                If to Executive to:

                      John F. McGuire, III
                      P.O. Box 113
                      Still River, MA 01467


                If to the Company to:

                      HemaSure Inc.
                      140 Locke Drive
                      Marlborough, Massachusetts   01752
                      Attn:  Chairman of the Board of Directors

or to such other address or such other person as Executive or the Company shall
designate in writing in accordance with this Section 15, except that any notice
regarding a change of notice address shall be effective only upon receipt.

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        16.     Headings.
                --------

               Headings to sections in this Agreement are for the convenience of
the parties only and are not intended to be a part of, or to affect the meaning
or interpretation of, this Agreement.

        17.     Governing Law.
                -------------

               This Agreement shall be governed by the laws of the Commonwealth
of Massachusetts without reference to any jurisdiction's principles of conflict
of laws.

        18.     Counterparts.
                ------------

              This Agreement may be executed in one or more counterparts, with
each counterpart constituting an original copy, but all of which, when taken
together, constituting one and the same instrument.


                            [signature page follows]


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               IN WITNESS WHEREOF, the Company and Executive have caused this
Employment Agreement to be executed as of the day and year first above written.


                                    HEMASURE INC.


                                    By:  /s/ Timothy J. Barberich
                                        -------------------------
                                        Name:
                                        Title:




                                    EXECUTIVE


                                    /s/ John F. McGuire, III
                                    ------------------------
                                    John F. McGuire, III