<PAGE>   1
                                                                     EXHIBIT 4.4

                              AGREEMENT AND RELEASE

         This AGREEMENT AND RELEASE dated as of November 23, 1999 by and among
Traian Micu ("Mr. Micu"), and CALOGIC, ("Calogic"), Alpha Semiconductor, Inc., a
subsidiary of Calogic ("Alpha Semiconductor") and SIPEX Corporation ("SIPEX")
(Calogic, Alpha Semiconductor and SIPEX being referred to herein collectively
sometimes as the "Companies").

                                   WITNESSETH:

         WHEREAS, CAT Acquisition Corporation I, a Delaware corporation and
wholly owned subsidiary of SIPEX ("Merger Sub"), Calogic, and SIPEX have entered
into an Agreement and Plan of Reorganization dated as of October 21, 1999
setting forth certain terms and conditions pursuant to which Merger Sub is being
merged with and into Calogic (the "Merger").

         WHEREAS, SIPEX is under no obligation to make the payments and
transfers set forth in Sections 2 and 3 of this Agreement and Release; and

         WHEREAS, Mr. Micu is entering into this Agreement and Release as part
of the inducement for SIPEX to make the payments as set forth in Sections 2 and
3 of this Agreement and Release.

         NOW THEREFORE, for good and valuable consideration more fully described
below, the parties hereto, intending to be legally bound, agree as follows:

         1. VOIDING OF PRIOR AGREEMENTS. Mr. Micu and Alpha Semiconductor and
Calogic hereby supercede and void all prior agreements and understandings
between them concerning the terms and conditions of employment, compensation
and/or bonus arrangements, including without limitation those contained in a
certain employment agreement between Mr. Micu and Alpha Semiconductor dated
November 1, 1995 and any amendments thereto (the "Employment Agreement") and
those contained in a certain service contract letter between Mr. Micu and Wayne
Luty dated July 7, 1997 and any amendments thereto (the "Service Contract")
PROVIDED HOWEVER, this Agreement and Release will not supersede any
nondisclosure and/or confidentiality agreements between Mr. Micu and the
Companies.

         2. PURCHASE OF SHARES OF ALPHA SEMICONDUCTOR. SIPEX will purchase from
Mr. Micu and Mr. Micu will transfer to SIPEX all right, title and interest in
all of the shares (the "Alpha Shares") of the common stock of Alpha
Semiconductor owned by Mr. Micu as of the date hereof. Mr. Micu represents and
warrants that (i) he is the sole beneficial owner and record holder of the Alpha
Shares, free and clear of any lien, pledge, hypothecation, restriction or
encumbrance; (ii) he has the full right and power to sell and transfer to SIPEX
the Alpha Shares, and the sale of the Alpha Shares provided for in this
Agreement and Release will vest in SIPEX good, valid and marketable title to the
Alpha Shares; and (iii) he is transferring all shares of the common stock of
Alpha Semiconductor owned or held by him pursuant to the terms herein. After
execution of this Agreement and upon payment by SIPEX of the consideration
described in Section 3, Mr. Micu shall deliver the stock certificate or
certificates evidencing the Alpha Shares,

<PAGE>   2

                         Agreement and Release - Page 2

duly endorsed for transfer to SIPEX and/or execute any stock power to transfer
the shares to SIPEX; whereupon Mr. Micu shall cease to be a stockholder of Alpha
Semiconductor.

         3. PAYMENTS. SIPEX shall issue one hundred thousand (100,000) shares of
its common stock, $.01 par value (the "SIPEX Shares"), to Mr. Micu as the
purchase price for the Alpha Shares and consideration for the other agreements
of Mr. Micu contained in this Agreement and Release. Mr. Micu acknowledges and
agrees that (i) the SIPEX Shares are being acquired for his own account for the
purpose of investment and not with a view to, or for sale in connection with,
the distribution thereof, nor with any present intention of distributing or
selling the SIPEX Shares, (ii) the SIPEX Shares may not be sold without
registration under the Securities Act of 1933, as amended, or an exemption
therefrom, (iii) prior to his acquisition of the SIPEX Shares he has had the
opportunity to ask questions of and receive answers from representatives of
SIPEX concerning the finances, operations and business of SIPEX, and (iv) he is
and has at all relevant times been capable of evaluating the merits and risks of
the acquisition of the Shares and can afford a complete loss of his investment
therein. SIPEX and Mr. Micu agree that Mr. Micu will become a party to that
certain Registration Rights Agreement to be executed by SIPEX in connection with
the Merger and for purpose of that Agreement, the SIPEX Shares shall be treated
as Merger Shares.

         4. EMPLOYMENT AT WILL. Mr. Micu understands and agrees that neither
this Agreement and Release nor any other document or representation regarding
employment with the Companies constitutes an implied or written employment
contract for employment with the Companies for a specified term.

         5. RELEASE. Notwithstanding the provisions of Section 1542 of the
California Civil Code, in exchange for the consideration set forth in this
Agreement and Release and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, Mr. Micu, on behalf of himself and
his representatives, agents, estate, heirs, executors, successors and assigns
(collectively and individually the "Releasor") absolutely and unconditionally
hereby remises, releases and forever discharges Calogic and its predecessors,
successors (including without limitation SIPEX), parents, investors,
subsidiaries (including, without limitation, Alpha Semiconductor), divisions,
affiliates, assigns and insurers as well as its and their present and former
officers, directors, members, shareholders, employees, attorneys, partners,
representatives and/or agents, both individually and in their official
capacities (collectively and individually the "Releasees"), of and from any and
all debts, demands, actions, causes of action, covenants, contracts, damages,
claims, rights, liabilities, suits, sums, accounts, complaints, obligations,
agreements, promises, charges, dues, costs, expenses, controversies and
judgments, of every kind and nature whatsoever, both at law and in equity,
existing or contingent, known or unknown, suspected or unsuspected arising out
of or in any way related to agreements, events, acts or conduct at any time
prior to and including the date Mr. Micu signs this Agreement and Release,
including, without limitation: (i) any and all claims that arise out of, relate
to or concern any agreements Mr. Micu may have concerning his employment or
otherwise, including the Employment Agreement including without limitation, any
bonus and/or other compensation arrangements and/or Mr. Micu's employment with
or change in employment status with Alpha Semiconductor and/or Calogic; (ii) any
and all claims that arise out of, relate to or concern the relationship between
Mr. Micu and the Companies, including without limitation those arising out

<PAGE>   3

                         Agreement and Release - Page 3


of Mr. Micu's status as a director, officer, shareholder, employee or partner
(including, but not limited to, all claims or demands related to salary,
bonuses, commissions, stock, stock options, or any other ownership interests,
vacation or time off pay, fringe benefits, expense reimbursements, severance
pay, or any other form of severance); (iii) any and all claims based on any
federal, state or local law, constitution or regulation regarding either
employment or employment discrimination and/or retaliation including, without
limitation, those laws or regulations concerning discrimination on the basis of
race, color, age, handicap, physical or mental disability, creed, religion, sex,
sex harassment, sexual orientation, marital status, national origin, ancestry,
veteran status, military service and/or application for military service
including, but not limited to, the federal Civil Rights Act of 1964, as amended,
the federal Americans with Disabilities Act of 1990, the federal Age
Discrimination in Employment Act of 1967, as amended, the California Fair
Employment and Housing Act, as amended; and (iv) any and all claims based on any
contract, whether oral or written, express or implied, any tort; (including,
without limitation, fraud or violation of securities laws), promissory estoppel
and/or any other statutory or common law claim of any nature whatsoever . This
provision is intended by the parties hereto to be all-encompassing and to act as
a full and total release of any claims, whether specifically enumerated herein
or not, that the Releasor has, may have or has had against the Releasees, from
the beginning of the world to the date of this Agreement and Release.

         (b) Mr. Micu hereby expressly waives any and all rights and benefits
conferred upon him by the provisions of Section 1542 of the California Civil
Code and expressly consents that this Agreement and Release shall be given full
force and effect according to each and all of its express terms and provisions,
including as well, those related to unknown and/or unsuspected claims, if any,
as well as those relating to any other claims specified in this Agreement and
Release. Section 1542 provides as follows:

         "A general release does not extend to claims which the creditor does
         not know or suspect to exist in his favor at the time of executing the
         release, which if known by him must have materially affected his
         settlement with the debtor."

         Mr. Micu further represents that he understands and acknowledges the
significance and consequence of such release as well as the specific waiver of
Section 1542.

         6. SETTLEMENT OF AMOUNTS DUE. Mr. Micu accepts the consideration
provided for in this Agreement and Release as full, complete and unconditional
payment, settlement, satisfaction and/or accord with respect to the sale of his
securities and any and all obligations and liabilities of the Releasees to the
Releasor, and with respect to all claims that could be asserted by Releasor
against the Releasees, including, without limitation, all potential claims for
wages, salary, commissions, bonuses, draws, incentive pay, deferred
compensation, stock and/or stock options, severance pay, vacation pay,
attorneys' fees, compensatory damages, exemplary damages, payment(s), expenses
and/or other compensation or benefits of any kind.

         7.       REPRESENTATIONS AND GOVERNING LAW.

                  (a) This Agreement and Release represents the complete and
sole understanding between the parties and supersedes any and all other
agreements and

<PAGE>   4

                         Agreement and Release - Page 4

understandings, whether oral or written including, specifically, without
limitation, the Employment Agreement and the Service Contract, PROVIDED,
HOWEVER, that nothing in this Agreement and Release will affect the
confidentiality and/or nondisclosure agreements between Mr. Micu and the
Companies, each of which shall remain in full force and effect in accordance
with their respective terms.

                  (b) Mr. Micu may not assign any of his rights or delegate any
of his duties or obligations under this Agreement and Release. The rights and
obligations of the Companies under this Agreement and Release shall inure to the
benefit of the successors and assigns of each of the Companies.

                  (c) This Agreement and Release may not be modified, altered or
amended except upon the express written consent of the Companies. The language
of all parts of this Agreement and Release shall in all cases be construed as a
whole according to its fair meaning and not strictly for or against any of the
parties. If any provision of this Agreement and Release, or part thereof, is
held invalid, void or voidable as against public policy or otherwise, the
invalidity shall not affect other provisions, or parts thereof, which may be
given effect without the invalid provision or part. To this extent, the
provisions, and parts thereof, of this Agreement and Release are declared to be
severable.

                  (d) This Agreement and Release shall be governed by and
construed in accordance with the laws of the Commonwealth of Massachusetts,
without giving effect to the principles of conflicts of laws thereof.

                  (e) MR. MICU ACKNOWLEDGES THAT HE HAS READ THE FOREGOING
AGREEMENT AND RELEASE, FULLY UNDERSTANDS THE TERMS AND CONDITIONS OF SUCH
AGREEMENT AND RELEASE AND HE IS VOLUNTARILY EXECUTING THE SAME. MR. MICU
ACKNOWLEDGES THAT HE WAS INFORMED AND UNDERSTANDS THAT THIS AGREEMENT AND
RELEASE CONTAINS A GENERAL RELEASE OF ALL CLAIMS KNOWN OR UNKNOWN WHICH HE MAY
BRING AGAINST THE COMPANIES. IN ENTERING INTO THIS AGREEMENT AND RELEASE, MR.
MICU ACKNOWLEDGES THAT HE IS NOT RELYING ON ANY REPRESENTATION, PROMISE OR
INDUCEMENT MADE BY THE COMPANIES NOT EXPRESSLY SET FORTH HEREIN.


                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

<PAGE>   5

                         Agreement and Release - Page 5


         IN WITNESS WHEREOF, the undersigned have executed this Agreement and
Release on the date first above written.


Witness: /s/ Alima Micu                 /s/ Traian Micu
        ---------------------------     ----------------------------------------
Name:                                   Name:


                                        COMPANIES:

                                        SIPEX CORPORATION


                                        By: /s/ James E. Donegan
                                           -------------------------------------
                                        Name:
                                        Title:


                                        CALOGIC


                                        By: /s/ Manuel Del Arroz
                                           -------------------------------------
                                        Name: Manuel Del Arroz
                                        Title: President


                                        ALPHA SEMICONDUCTOR, INC.


                                        By: /s/ Manuel Del Arroz
                                           -------------------------------------
                                        Name: Manuel Del Arroz
                                        Title: President