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                                                                  EXHIBIT 10.2

                                 AMENDMENT NO. 2
                                       TO
                                CREDIT AGREEMENT

         Amendment No. 2 to CREDIT AGREEMENT dated as of September 28, 2004 (as
amended and modified prior to the date hereof, the "Loan Agreement"), among
BIOCREST MANUFACTURING, L.P., a Delaware limited partnership having its
principal office at 1834 State Highway 71 West, Cedar Creek, Texas 78612
("Customer"), STRATAGENE CORPORATION, a Delaware corporation (formerly known as
Stratagene Holding Corporation), having its principal office at 11011 North
Torrey Pines Road, La Jolla, California 92037 ("Stratagene"), BIOCREST HOLDINGS,
L.L.C., a Delaware limited liability company, having its principal office at
5320 Pine Meadow Road, Wilson, Wyoming 83014 ("BH LLC"), and MERRILL LYNCH
BUSINESS FINANCIAL SERVICES INC., a corporation organized and existing under the
laws of the State of Delaware having its principal office at 222 North LaSalle
Street, 17th Floor, Chicago, IL 60601 ("MLBFS").

         WHEREAS, MLBFS, Customer, Stratagene and BH LLC wish to amend the Loan
Agreement in certain respects,

         NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration (the receipt and adequacy of which are hereby
acknowledged), the parties hereto hereby agree as follows:

         1. Definitions. All capitalized terms used herein which are defined in
the Loan Agreement and not otherwise defined herein are used herein as defined
therein.

         2. Amendments to Loan Agreement.

            (a) The definition of "Commitment Expiration Date" in Section 1.1 of
the Loan Agreement is hereby amended in its entirety to read as follows:

         "COMMITMENT EXPIRATION DATE" shall mean (i) the Maturity Date, in the
case of WCMA Revolving Loans, WCMA Reducing Revolving Loans and the WCMA LC Line
of Credit, (ii) January 23, 2004 in the case of the Term Loans or (iii) in each
case described in clause (i) and (ii), if earlier, the date on which the
commitments of MLBFS hereunder are terminated pursuant to Section 7.6.


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            (b) The definition of "Maturity Date" in Section 1.1 of the Loan
Agreement is hereby amended in its entirety to read as follows:

         "MATURITY DATE" shall mean (i) in the case of the WCMA Revolving Loans,
January 31, 2005 (subject to renewal in accordance with the terms hereof), (ii)
in the case of the WCMA Reducing Revolver, January 31, 2007, (iii) in the case
of the Term Loan, May 1, 2006, and (iv) in the case of the WCMA L/C Line of
Credit, July 31, 2005 (subject to renewal in accordance with the terms hereof).

            (c) The parenthetical definition of "Direct Pay Letter of Credit" in
clause (ii) of Section 6.1 of the Loan Agreement is hereby amended in its
entirety to read as follows:

         (as the same may be amended by the Issuing Bank, a "Direct Pay Letter
of Credit" and together with the Back to Back L/C, each a "Letter of Credit" and
collectively, the "Letters of Credit")

            (d) Section 6.4 of the Loan Agreement is hereby amended in its
entirety to read as follows:

         6.4 RENEWAL AT OPTION OF MLBFS; RIGHT OF CUSTOMER TO TERMINATE. MLBFS
may at any time, prior to January 31 in each year (beginning January 31, 2005),
in its sole discretion and at its sole option, renew the WCMA L/C Line of Credit
for an additional twelve month period ending on the next anniversary of the then
Maturity Date for the WCMA L/C Line of Credit; it being understood, however,
that no such renewal shall be effective unless set forth in a writing executed
by a duly authorized representative of MLBFS and delivered to Customer. Any such
renewal shall extend the Commitment Expiration Date for the WCMA L/C Line of
Credit to the next anniversary of such Commitment Expiration Date. Unless any
such renewal is accompanied by a proposed change in the terms of the WCMA L/C
Line of Credit (other than the extension of the Maturity Date), no such renewal
shall require Customer's approval. Customer shall, however, have the right to
terminate the WCMA L/C Line of Credit at any time upon written notice to MLBFS;
provided that no such termination shall affect any issued and outstanding Letter
of Credit or Customer's Obligations with respect thereto.


         3. Representations and Warranties. In order to induce MLBFS to enter
into this Amendment No. 2, Customer, Stratagene and BH LLC (with respect to
itself only) makes the following representations and warranties to MLBFS which
shall survive the execution and delivery hereof:


            (a) Each Business Credit Party is duly organized, validly existing
and in good standing under the laws of its state of organization. Each Business
Credit Party is qualified to do business and in good standing in each other
state where the nature of its business or the property owned by it make such
qualification necessary, except for such states where the failure to so qualify
or be in good standing would not have a Material Adverse Effect;


            (b) The execution and delivery of this Amendment No. 2 has been
authorized by all requisite action on the part of each Business Credit Party,
this Amendment No.


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2 has been duly executed and delivered by it, and this Amendment No. 2 and the
Loan Agreement, as amended hereby constitute its legal, valid and binding
obligations enforceable in accordance with their respective terms subject to
applicable bankruptcy, insolvency, reorganization and other laws affecting
creditors' rights generally, moratorium laws from time to time in effect and
general principles of equity (regardless of whether such enforceability is
considered in a proceeding in equity or at law); and

            (c) No action of, or filing with, any governmental or public body or
authority is required to authorize, or is otherwise required in connection with
the execution, delivery and performance of this Amendment No. 2 by Customer,
Stratagene or BH LLC.

         4. Expenses. Customer shall pay all reasonable expenses, including,
without limitation, reasonable legal fees, incurred by MLBFS in connection with
the preparation, negotiation, execution and delivery and review of this
Amendment No. 2, and all other documents and instruments executed in connection
with this transaction.

         5. References to Loan Agreement. The Loan Agreement is, and shall
continue to be, in full force and effect and is hereby ratified and confirmed in
all respects except that after giving effect to this Amendment No. 2 all
references in the Loan Agreement to "this Agreement", "hereto", "hereof",
"hereunder" or words of like import referring to the Loan Agreement shall mean
the Loan Agreement, as amended.

         6. Amendment No. 2. This Amendment No. 2 is limited as written and
shall not be deemed (i) to be an amendment of or a consent under or waiver of
any other term or condition of the Loan Agreement, or any of the other Loan
Documents or (ii) to prejudice any right or rights which MLBFS now has or may
have in the future under or in connection with the Loan Agreement or the other
Loan Documents except as expressly waived hereby.

         7. Security Documents. It is agreed and confirmed that after giving
effect to this Amendment No. 2 that each Loan Document remains in full force and
effect.

         8. Governing Law. This Amendment No. 2, including the validity thereof
and the rights and obligations of the parties hereunder, shall be construed in
accordance with and governed by the laws of the State of Illinois.

         9. Counterparts. This Amendment No. 2 may be executed by one or more of
the parties to this Amendment No. 2 on any number of separate counterparts, and
all of said counterparts taken together shall be deemed to constitute one and
the same instrument.

        [REMAINDER OF PAGE INTENTIONALLY BLANK, SIGNATURES ON NEXT PAGE]


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         IN WITNESS WHEREOF, the undersigned have executed this Amendment No. 2
this 29th day of September, 2004.

                                       MERRILL LYNCH BUSINESS
                                       FINANCIAL SERVICES INC.

                                       By:               /s/ PATRICK LUCAS
                                          --------------------------------------
                                           Name:  PATRICK LUCAS
                                           Title:  Vice President


                                       BIOCREST MANUFACTURING, L.P.

                                       By:      BioCrest Management, L.L.C.
                                       Its:     General Partner


                                       By:          /s/ JOSEPH A. SORGE, M.D.
                                          --------------------------------------
                                           Name:  JOSEPH A. SORGE, M.D.
                                           Title:  Sole Member

                                       STRATAGENE CORPORATION


                                       By:          /s/ JOSEPH A. SORGE, M.D.
                                          --------------------------------------
                                           Name:  JOSEPH A. SORGE, M.D.
                                           Title:  Chief Executive Officer

                                       BIOCREST HOLDINGS, L.L.C.


                                       By:          /s/ JOSEPH A. SORGE, M.D.
                                          --------------------------------------
                                           Name:  JOSEPH A. SORGE, M.D.
                                           Title:  Sole Manager


                                       The undersigned consent to the foregoing
                                       and acknowledge that the Loan Documents
                                       to which they are a party remain in full
                                       force and effect.

                                       STRATAGENE CALIFORNIA

                                       By:          /s/ JOSEPH A. SORGE, M.D.
                                          --------------------------------------
                                           Name:  JOSEPH A. SORGE, M.D.
                                           Title:  Chief Executive Officer


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                                       BIOCREST CORPORATION

                                       By:          /s/ JOSEPH A. SORGE, M.D.
                                          --------------------------------------
                                           Name:  JOSEPH A. SORGE, M.D.
                                           Title:  Chief Executive Officer


                                       BIOCREST MANAGEMENT, L.L.C.

                                       By:          /s/ JOSEPH A. SORGE, M.D.
                                          --------------------------------------
                                           Name:  JOSEPH A. SORGE, M.D.
                                           Title:  Sole Manager


                                       BIOCREST LIMITED, L.L.C.

                                       By:          /s/ JOSEPH A. SORGE, M.D.
                                          --------------------------------------
                                           Name:  JOSEPH A. SORGE, M.D.
                                           Title:  Sole Manager

                                       PHENOGENEX, L.L.C.

                                       By:          /s/ JOSEPH A. SORGE, M.D.
                                          --------------------------------------
                                           Name:  JOSEPH A. SORGE, M.D.
                                           Title:  Sole Manager


                                       BIOCREST SALES, L.P.

                                       By:      BIOCREST MANAGEMENT, L.L.C.
                                       Its:     General Partner

                                       By:          /s/ JOSEPH A. SORGE, M.D.
                                          --------------------------------------
                                           Name:  JOSEPH A. SORGE, M.D.
                                           Title:  Sole Manager


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