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                                  EXHIBIT 3(A)
                                  ------------

         CERTIFICATE OF AMENDMENT OF THE CERTIFICATE OF INCORPORATION
         ------------------------------------------------------------ 
                OF LIFE TECHNOLOGIES, INC. DATED APRIL 14, 1998
               ----------------------------------------------- 

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                                                                    EXHIBIT 3(A)
                                                                                
                          CERTIFICATE OF AMENDMENT OF
                      THE CERTIFICATE OF INCORPORATION OF
                            LIFE TECHNOLOGIES, INC.

          LIFE TECHNOLOGIES, INC., a corporation organized and existing under
and by virtue of the General Corporation Law of the State of Delaware (the
"Corporation"), DOES HEREBY CERTIFY:

          FIRST:  That at a meeting of the Board of Directors of the Corporation
held on February 10, 1998, the Board of Directors of the Corporation duly
adopted a resolution setting forth a proposed amendment to Article EIGHTH of the
Certificate of Incorporation, as amended, of the Corporation (the
"Certificate"), declaring said amendment to be advisable and directing that the
proposed amendment be placed before the stockholders of the Corporation for
consideration thereof.  The resolution setting forth the proposed amendment is
as follows:

               RESOLVED, that Article EIGHTH, subsection (3)(ii), of the
               Certificate be amended to read in its entirety in the form
               attached hereto as Attachment A;

          SECOND: That thereafter, pursuant to resolution of the Board of
Directors of the Corporation, the annual meeting of stockholders of the
Corporation was duly called and held, at which meeting the necessary number of
stockholders as required by statute and by the Certificate voted in favor of and
approved said amendment to the Certificate.

          THIRD: That said amendment was duly adopted in accordance with the
provisions of Section 242 of the General Corporation Law of the State of
Delaware.

          IN WITNESS WHEREOF, LIFE TECHNOLOGIES, INC. has caused this
certificate to be signed by its President and attested by its Secretary, who
hereby affirm, under penalties of perjury, that this certificate is the act and
deed of the Corporation and that the facts stated herein are true.


Date:  April 14, 1998              /s/ J. Stark Thompson
                                   -----------------------------------
                                   J. Stark Thompson
                                   President

ATTEST:


/s/ Joseph C. Stokes, Jr
------------------------ 
Joseph C. Stokes, Jr.
Secretary

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                                                         EXHIBIT 3(A) - PAGE TWO
                                                                                
                                                                    ATTACHMENT A

          (ii) The term "Business Combination with a Related Person" shall mean
(a) the consolidation or merger of the Corporation or any Subsidiary with or
into any "Related Person" (as hereinafter defined) or any other corporation
(whether or not itself a Related Person) which is, or after such merger or
consolidation would be, an Affiliate (as hereinafter defined) of a Related
Person, (b) any sale, lease, exchange, mortgage, pledge, transfer or other
disposition (in one or a series of transactions) to or with any Related Person
or any Affiliate of a Related Person of any Substantial Part of the assets or
business of the Corporation or any Subsidiary, (c) any sale, lease, exchange,
mortgage, pledge, transfer or other disposition, of all or any Substantial Part
of the assets of a Related Person or an Affiliate of a Related Person to the
Corporation or a Subsidiary, (d) the issuance or transfer by the Corporation or
a Subsidiary (in one transaction or a series of transactions) of any securities
of the Corporation or any Subsidiary to any Related Person or any Affiliate of
any Related Person, except the issuance of shares of Common Stock of the
Corporation to The Dexter Corporation pursuant to the terms of a Merger
Agreement, dated September 1, 1983, between the Corporation and Bethesda
Research Laboratories, Inc., (e) any reclassification of securities (including
any reverse stock split), or recapitalization of the Corporation, or any merger
or consolidation of the Corporation with any of its Subsidiaries or any other
transaction (whether or not with or into or otherwise involving a Related
Person), which has the effect, directly or indirectly, of increasing the
proportionate share of the outstanding shares of any class of equity or
convertible securities of the Corporation or any Subsidiary which is directly or
indirectly owned by any Related Person or any Affiliate of any Related Person,
except as a result of immaterial changes due to fractional share adjustments or
as a result of any purchase or redemption of any shares of stock by the
Corporation, (f) a Combination or Majority Share Acquisition involving a Related
Person in which the Corporation is the Acquiring Corporation and its Common
Stock is issued or transferred in connection with such Combination or Majority
Share Acquisition, and (g) any agreement, contract or other arrangement
providing for any of the transactions described in this definition of Business
Combination with a Related Person.

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