Exhibit 10.28



                                  HemaSure Inc.

                       Amendment to 1994 Stock Option Plan
                       -----------------------------------

               Adopted by the Board of Directors on June 25, 1996



RESOLVED: That Section 16 of the Company's 1994 Stock Option Plan be and hereby
          is amended to read in its entirety as follows:

          16. Merger, Consolidation, Asset Sale, Liquidation, etc.

               (a) General. Subject to Section 16(c), in the event of a
          consolidation or merger or sale of all or substantially all of the
          assets of the Company in which outstanding shares of Common Stock are
          exchanged for securities, cash or other property of any other
          corporation or business entity or in the event of a liquidation of the
          Company, the Board of Directors of the Company, or the board of
          directors of any corporation assuming the obligations of the Company,
          may in its discretion, take any one or more of the following actions,
          as to outstanding options: (i) provide that such options shall be
          assumed, or equivalent options shall be substituted, by the acquiring
          or succeeding corporation (or an affiliate thereof), provided that any
          such options substituted for Incentive Stock Options shall meet the
          requirements of Section 424(a) of the Code, (ii) upon written notice
          to the optionees, provide that all unexercised options will terminate
          immediately prior to the consummation of such transaction unless
          exercised by the optionee (to the extent then exercisable) within a
          specified period following the date of such notice, and (iii) in the
          event of a merger under the terms of which holders of the Common Stock
          of the Company will receive upon consummation thereof a cash payment
          for each share surrendered in the merger (the "Merger Price"), make or
          provide for a cash payment to the optionees equal to the difference
          between (A) the Merger Price times the number of shares of Common
          Stock subject to such outstanding options (to the extent then
          exercisable at prices not in excess of the Merger Price) and (B) the
          aggregate exercise price of all such outstanding options in exchange
          for the termination of such options.

               (b) Substitute Options. The Company may grant options under the
          Plan in substitution for options held by employees of another
          corporation who become employees of the Company, or a subsidiary of
          the Company, as a result of a merger or consolidation of the employing
          corporation with the Company or a subsidiary of the Company, or as a
          result of the acquisition by the Company, or one of its



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          subsidiaries, of property or stock of the employing corporation. The
          Company may direct that substitute options be granted on such terms
          and conditions as the Board of Directors considers appropriate in the
          circumstances.

               (c) Change in Control. Notwithstanding any other provision\
          contained herein, in the event of a "Change in Control" of the Company
          (as defined below) each outstanding option under the Plan held by a
          person who is then an employee of the Company shall immediately become
          exercisable in full. For purposes of the Plan, a "Change in Control"
          shall be deemed to have occurred only if any of the following events
          occurs: (i) any "person", as such term is used in Sections 13(d) and
          14(d) of the Exchange Act (other than the Company, any trustee or
          other fiduciary holding securities under an employee benefit plan of
          the Company, or any corporation owned directly or indirectly by the
          stockholders of the Company in substantially the same proportion as
          their ownership of stock of the Company), is or becomes the
          "beneficial owner" (as defined in Rule 13D-3 under the Exchange Act),
          directly or indirectly, of securities of the Company representing 50%
          or more of the combined voting power of the Company's then outstanding
          securities; (ii) the stockholders of the Company approve a merger or
          consolidation of the Company with any other corporation, other than a
          merger or consolidation which would result in the voting securities of
          the Company outstanding immediately prior thereto continuing to
          represent (either by remaining outstanding or by being converted into
          voting securities of the surviving entity) more than 50% of the
          combined voting power of the voting securities of the Company or such
          surviving entity outstanding immediately after such merger or
          consolidation; (iii) the stockholders of the Company approve a plan of
          complete liquidation of the Company or an agreement for the sale or
          disposition by the Company of all or substantially all of the
          Company's assets; or (iv) individuals who, on the date on which the
          Plan was adopted by the Board of Directors, constituted the Board of
          Directors of the Company, together with any new director whose
          election by the Board of Directors or nomination for election by the
          Company's stockholders was approved by a vote of at least a majority
          of the directors then still in office who were directors on the date
          on which the Plan was adopted by the Board of Directors or whose
          election or nomination was previously so approved, cease for any
          reason to constitute at least a majority of the Board of Directors.


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