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[COMERICA BANK LOGO]

                                                                   Exhibit 10.24

                  MODIFICATION TO LOAN AND SECURITY AGREEMENT

          This First modification to Loan and Security Agreement (this
"Modification") is entered into by and between SIPEX CORPORATION ("Borrower")
and COMERICA BANK-CALIFORNIA ("Bank") as of this 28th day of November, 2001, at
San Jose, California.

                                    RECITALS

          This Modification is entered into upon the basis of the following
facts and understandings of the parties, which facts and understandings are
acknowledged by the parties to be true and accurate.


          Bank and Borrower previously entered into an Amended and Restated
Revolving Credit Loan and Security Agreement (Accounts and Inventory) dated
March 22, 2001. The Amended and Restated Revolving Credit Loan and Security
Agreement and each modification shall collectively be referred to herein as the
"Agreement".

          NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties agree as set forth
below.


                                   AGREEMENT

          1.  Incorporation by Reference. The Recitals and the documents
referred to therein are incorporated herein by this reference. Except as
otherwise noted, the terms not defined herein shall have the meaning set forth
in the Agreement.

          2.  Modification to the Agreement. Subject to the satisfaction of the
conditions precedent as set forth in Section 3 hereof, the Agreement is hereby
modified as set forth below:

               A. Section 7.16b, first line, is hereby amended by changing
               "month" to "quarter".

               B.  Section 7.17, first and second line, is hereby deleted in its
               entirety and replaced with the following:

                    "7.17 Borrower shall maintain the following financial ratios
                    and covenants on a consolidated and non-consolidated basis,
                    which shall be monitored on a monthly basis, except as noted
                    below:"

               C.  Section 7.17c is hereby deleted in its entirety and replaced
               with the following:

                    "c.  A ratio of Current Assets to Current Liabilities of not
                    less than 2.00:1.00."

               D.  Section 7.17d. is hereby deleted in its entirety and replaced
               with the following:
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     "d.  A ratio of Quick Assets to Current Liabilities of not less than
     0.65:1.00 to increase to 0.75:1.00 on 12/31/01 and l.00:1.00 on 12/31/02
     to be monitored quarterly"

E.   Section 7.17e. is hereby deleted in its entirety and replaced with the
     following:

     "e. A ratio of Debt-to-Worth of less than 0.35:1.00 monitored quarterly."

F.   Section 7.17g. is hereby deleted in its entirety and replaced with the
     following:

     "g. Net Income after taxes of ($2,000,000) for the quarter ending
     December 31, 2001,


                                      -1-
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          ($1,500,000) for the quarter ending March 31, 2002, ($1,400,000) for
          the quarter ending June 30, 2002, ($700,000) for the quarter ending
          September 30, 2002, and ($200,000) for the quarter ending 2002"

     3    Legal Effect. The effectiveness of this Modification is conditioned
upon receipt by Bank of this Modification, and any other documents which Bank
may require to carry out the terms hereof. Except as specifically set forth in
this Modification, all of the terms and conditions of the Agreement remain in
full force and effect.

     4    Integration. This is an integrated Modification and supersedes all
prior negotiations and agreements regarding the subject matter hereof. All
amendments hereto must be in writing and signed by the parties.




     IN WITNESS WHEREOF, the parties have agreed as of the date first set forth
above.


SIPEX CORPORATION                                     COMERICA BANK-CALIFORNIA


By:   /s/ Frank DiPietro                            By:   /s/ Matthew Wright
      ---------------------------                    ---------------------------
Title: Executive Vice President                      Matthew Wright
      ---------------------------                    Corporate Banking Officer



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