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EXHIBIT 4.2


                                     BY-LAWS

                                       OF

                        PROFILE DIAGNOSTIC SCIENCES, INC.

                                    * * * * *


                                    ARTICLE I

                               Name of Corporation
                               -------------------

         SECTION 1: This corporation shall be known as PROFILE DIAGNOSTICS
SCIENCES, INC.

                                   ARTICLE II

                                     Offices
                                     -------

         SECTION 1: The registered office of the corporation will be located in
the City of Wilmington, County of New Castle, State of Delaware. The corporation
may maintain such other offices as the Board of Directors may designate from
time to time.

                                  ARTICLE III

                                  Stockholders
                                  ------------

         SECTION 1: The annual meeting of the stockholders shall be held in July
of each year, at a date and time to be specified by the Board of Directors. Said
meeting shall be for the purpose of electing directors for the ensuing year and
for the transaction of such other business as may come before the meeting. If
the election of directors shall not be held on the date designated for the
annual meeting of the stockholders, or at any adjournment thereof, the Board of
Directors shall cause the election to be held at a special meeting of the
stockholders as soon thereafter as possible.

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         SECTION 2: Special meetings of the stockholders, for any purpose or
purposes, unless otherwise prescribed by Statute, may be called by the President
or by the Board of Directors and shall be called by the President at the request
of the holders of not less than one-tenth of all the outstanding shares of the
corporation entitled to vote at the meeting.

         SECTION 3: The Board of Directors may designate any place within or
without the State of Delaware as the site for any annual or special stockholders
meeting. A waiver of notice signed by all stockholders entitled to vote at a
meeting may designate any place, either within or without the State of Delaware,
as the site for any meeting hereinabove authorized. If no designation is made,
the place of the meeting shall be at the registered office of the corporation in
the State of Delaware.

         SECTION 4: Written or printed notice stating the site, date and time of
the meeting and, in case of a special meeting, the purpose or purposes for which
the meeting is called, shall be delivered not less than ten (10) days nor more
than sixty (60) days before the date of the meeting, either personally or by
mail, by or at the direction and over the signature of the President, or the
Secretary, or the officer or person calling the meeting, to each stockholder of
record entitled to vote at such meeting. If mailed, such notice shall be deemed
to be delivered when deposited in the United States mail, addressed to the
stockholder at his address as it appears on the stock transfer books of the
corporation, with postage thereon prepaid.


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         SECTION 5: For the purpose of determining stockholders entitled to
notice of or to vote at a meeting of stockholders, or any adjournment thereof,
or stockholders entitled to receive payment of any dividend, or in order to make
a determination of stockholders for any other proper purpose, the Board of
Directors of the corporation may provide that the stock transfer books shall be
closed for a stated period, not to exceed twenty (20) days. In lieu of closing
the stock transfer books, the Board of Directors may fix in advance a date as
the record date for any such determination of stockholders, such date in any
case to be not more than sixty (60) days and, in case of a meeting of
stockholders, not less than fifteen (15) days prior to the date on which the
particular action requiring such determination of stockholders is to be taken.
If the stock transfer books are not closed and no record dates fixed for the
determination of stockholders entitled to notice of or to vote, or entitled to
receive payment of a dividend, the date on which notice of the meeting is mailed
or the date on which the resolution of the Board of Directors declaring such
dividend is adopted, as the case may be, shall be the record date for such
determination of stockholders. When a determination of stockholders entitled to
vote at any meeting of stockholders has been made as provided in this section,
such determination shall apply to any adjournment thereof, except where the
determination has been made through the closing of the stock transfer books and
the stated period of closing has expired.

         SECTION 6: The officer or agent having charge of the stock transfer
books for share of the corporation shall make, at least ten (10) days before
each meeting of stockholders, a complete list of the stockholders entitled to
vote at such meeting, or any adjournment thereof, arranged in alphabetical
order, with the address of, and the number of shares held by, each, which list
for a period of ten (10) days prior to such meeting, shall be kept on file at
the principal office of the corporation and shall be subject to the inspection
of any stockholder during the meeting.


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         SECTION 7: A majority of the outstanding shares of the corporation
entitled to vote, represented in person or by proxy, shall constitute a quorum
at a meeting of stockholders. If less than a majority of the outstanding shares
are represented at a meeting, a majority of the shares so represented may
adjourn the meeting from time to time without further notice. At such adjourned
meeting at which a quorum shall be present or represented, any business may be
transacted which might have been transacted at the meeting as originally
notified. The stockholders present at a duly organized meeting may continue to
transact business until adjournment, notwithstanding the withdrawal of enough
stockholders to leave less than a quorum.

         SECTION 8: At all meetings of stockholders, a stockholder may vote by
proxy which shall be executed in writing by the stockholder or by his duly
authorized attorney in fact. Such proxy shall be filed with the Secretary of the
corporation before or at the time of the meeting. No proxy shall be valid after
six (6) months from the date of its execution, unless otherwise provided in the
proxy or coupled with an interest.

         SECTION 9: Each outstanding share otherwise entitled to vote shall be
entitled to one (1) vote upon each matter submitted to a vote at a meeting of
stockholders. A majority vote of those shares present and voting at a duly
organized meeting shall suffice to defeat or enact any proposal unless the
Statutes of the State of Delaware require a greater-than-majority vote, in which
event the higher vote shall be required for the action to constitute the action
of the corporation.


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         SECTION 10: Shares held by an administrator, executor, guardian or
conservator may be voted by him, either in person or by proxy, without the
transfer of such shares into his name. Shares standing in the name of a trustee
may be voted by him, either in person or by proxy, but no trustee shall be
entitled to vote shares held by him without transfer of such shares into his
name.

         Shares standing in the name of a receiver may be voted by such
receiver, and shares held by or under the control of a receiver may be voted by
such receiver without the transfer thereof into his name if authority to do so
be contained in an appropriate order of the Court by which such receiver was
appointed.

         A stockholder whose shares are pledged shall be entitled to vote such
shares until the shares are transferred into the name of the pledgee, and
thereafter the pledgee shall be entitled to vote the shares so transferred.

         Shares of its own stock belonging to the corporation or held by it in a
fiduciary capacity shall not be voted, directly or indirectly, at any meeting,
and shall not be counted in determining the total number of outstanding shares
at any given time.

         SECTION 11: An action required to be taken at a meeting of the
stockholders, or any other action which may be taken at a meeting of the
stockholders, may be taken without a meeting, if a consent in writing, setting
forth the action so taken, shall be signed by a majority of the stockholders
entitled to vote with respect to the subject matter thereof, unless a
greater-than-majority vote would be required at a duly organized meeting, in
which event said greater-than-majority stockholder approval must be obtained.
Such consent shall be filed with the Minutes of Proceedings.


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         SECTION 12: The following order of business shall be observed at all
meetings of the stockholders, so far as practicable:

         (a)  Calling the roll;

         (b)  Reading, correcting and approving of minutes of previous meeting;

         (c)  Reports of officers;

         (d)  Reports of Committees;

         (e)  Election of Directors;

         (f)  Unfinished business;

         (g)  New business; and

         (h)  Adjournment.

                                   ARTICLE IV

                               Board of Directors
                               ------------------

         SECTION 1: The business and affairs of the corporation shall be managed
by its Board of Directors.

         SECTION 2: As provided in the Certificate of Incorporation, the Board
of Directors shall consist of five (5) persons, but may be increased by
resolution of the Board of Directors. The directors shall hold office until the
next annual meeting of stockholders and until their successor shall have been
elected and qualified. Directors need not be residents of the State of Delaware
or stockholders of the corporation.


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         SECTION 3: Directors shall be elected at an annual or special
stockholders' meeting by secret ballot of those stockholders present and
entitled to vote, a plurality of the vote being cast being required to elect.
Each stockholder shall be entitled to one (1) vote for each share of stock
owned. If there is but one (1) nominee for any office, it shall be in order to
move that the Secretary cast the elective ballot to elect the nominee.

         SECTION 4: A regular meeting of the Board of Directors shall be held
without notice, other than this By-Law immediately after, and at the same place
as, the annual meeting of stockholder. The Board of Directors may provide, by
resolution, the day, time and place for the holding of additional regular
meetings without other notice than such resolution. The Secretary of the
corporation shall serve as Secretary for the Board of Directors and shall issue
notices for all meetings as required by the By-Laws; shall keep a record of the
minutes of the proceedings of the meetings of directors; and shall perform such
other duties as may be properly required of him by the Board of Directors.

         SECTION 5: Special meetings of the Board of directors may be called by
or at the request of the President or any director. The person or persons
authorized to call special meetings of the Board of Directors may fix any place,
within or without the State of Delaware, as the place for holding any special
meeting of the Board of Directors called by them.


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         SECTION 6: Notice of any special meeting shall be given at least two
(2) days prior thereto by written notice delivered personally or mailed to each
director at his business address, or by telegram. If mailed, such notice shall
be deemed to be delivered when deposited in the United States mail so addressed,
with postage prepaid thereon. If notice be given by telegram, such notice shall
be deemed to be delivered when the telegram is delivered to the telegraph
company. Any director may waive notice of any meeting. The attendance of a
director at a meeting shall constitute a waiver of notice of such meeting,
except where a director attends a meeting for the express purpose of objecting
to the transaction of any business to be transacted at, nor the purpose of, any
regular or special meeting of the Board of Directors need be specified in the
notice or waiver of such meeting.

         SECTION 7: A majority of the number of directors fixed according to
Section 2 of this Article IV shall constitute a quorum for the transaction of
business at any meeting of the Board of Directors, but if less than such
majority is present at a meeting, a majority of the directors present may
adjourn the meeting from time to time without further notice. Once a quorum has
been established at a duly organized meeting, the Board of Directors may
continue to transact corporate business until adjournment, notwithstanding the
withdrawal of enough members to leave less than a quorum.

         SECTION 8: The act of the majority of the Directors present at a
meeting at which a quorum is present shall be the act of the Board of Directors
unless the Statutes of the State of Delaware require a greater-than-majority
vote, in which case, such greater vote shall be required for the act to be that
of the Board of Directors.

         SECTION 9: Any vacancy occurring in the Board of Directors may be
filled by the affirmative vote of a majority of the remaining directors, though
less than a quorum of the Board of Directors. A director elected to fill a
vacancy shall be elected for the unexpired term of his predecessor in office.
Any directorship to be filed by reason of an increase in the number of directors
shall be filled by election at an annual meeting or at a special meeting of the
stockholders called for that purpose.


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         SECTION 10: By resolution of the Board of Directors, the directors may
be paid their expenses, if any, of attendance at each meeting of the Board of
Directors, and may be paid a fixed sum for attendance at each meeting of the
Board of Directors or a stated salary as director. No such payment shall
preclude any director from serving the corporation in any other capacity and
receiving compensation therefor.

         SECTION 11: A director of the corporation who is present at a meeting
of the Board of Directors at which action on any corporate matter is taken shall
be presumed to have assented to the action taken unless his dissent shall be
entered in the minutes of the meeting or unless he shall file his written
dissent to such action with the Secretary of the Meeting before the adjournment
thereof or shall express such dissent by written notice sent by registered mail
to the Secretary of the corporation within one (1) day after the adjournment of
the meeting. Such right to dissent shall not apply to a director who voted in
favor of such action.

         SECTION 12: Any action required to be taken at a meeting of the Board
of Directors, or any other action which may be taken at a meeting of the Board
of Directors, may be taken without a meeting if a written consent thereto is
signed by all the members of the proceedings of the Board. Any meeting of the
Board of Directors may be held by conference telephone call, with minutes
thereof duly prepared and entered into the Minute Book.


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                                    ARTICLE V
                                    OFFICERS

         SECTION 1: The officers of the corporation shall be a President, a
Vice-President, a Secretary, a Treasurer, and a Resident Agent, each of whom
shall be elected by the Board of Directors. Other officers and assistant
officers may be authorized and elected or appointed by the Board of Directors.
Any two (2) or more offices may be held by the same person.

         SECTION 2: The officers of the corporation shall be elected annually by
the Board of Directors at the first meeting of the Board of Directors held after
each annual meeting of the stockholders. If the election of officers shall not
be held at such meeting, such election shall be held as soon thereafter as
convenient. Each officer shall hold office until his successor shall have been
duly elected and shall have qualified or until his death or until he shall
resign or shall be removed in the manner hereinafter provided. Each officer
shall serve for a term of one (1) year, or until his successor is chosen and
qualified.

         SECTION 3: Any officer or agent elected or appointed by the Board of
Directors may be removed by the Board of Directors whenever in its judgment the
best interests of the corporation would be served thereby, but such removal
shall be without prejudice to the contract rights, if any, of the person so
removed.

         SECTION 4: A vacancy in any office because of death, resignation,
removal, disqualification or otherwise, may be filled by majority vote of the
Board of Directors for the unexpired portion of the term of such office.


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         SECTION 5: The President shall preside at all meetings of the directors
and the stockholders and shall have general charge and control over the affairs
of the corporation subject to the Board of Directors. He shall sign or
countersign all certificates, contracts and other instruments of the corporation
as authorized by the Board of Directors and shall perform such other duties as
are incident to his office or are required of him by the Board of Directors.

         SECTION 6: The Vice-President shall exercise the functions of the
President, in the President's absence, and shall have such powers and duties as
may be assigned to him from time to time by the Board of Directors.

         SECTION 7: The Secretary shall issue notices for all meetings as
required by the By-Laws, shall keep a record of the minutes of the proceedings
of the meetings of stockholders and directors, shall have charge of the Seal and
of the corporate books, and shall make such reports and perform such other
duties as are incident to his office, or properly required of him by the Board
of Directors. The Assistant-Secretary shall perform all duties of these duties
at the direction of or in the absence of the Secretary.

         SECTION 8: The Treasurer shall have the custody of all monies and
securities of the corporation and shall keep regular books of account. He shall
disburse the funds of the corporation in payment of the just demands against the
corporation, or as may be ordered by the Board of Directors, taking proper
vouchers for such disbursements, and shall render to the Board of Directors,
from time to time as may be required of him, an account of all his transactions
as Treasurer and of the financial condition of the corporation. He shall perform
all duties incident to this office or which are properly required of him by the
Board of Directors.


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         SECTION 9: The Resident Agent shall be in charge of the corporation's
registered office, upon whom process against the corporation may be served, and
shall perform all duties required of him by statute.

         SECTION 10: The salaries of all officers shall be fixed by the Board of
Directors, and may be changed from time to time by a majority vote of the Board
of Directors.

                                   ARTICLE VI

                             Agreements and Finances
                             -----------------------

         SECTION 1: The Board of Directors may authorize any officer or
officers, agent or agents, to enter into any contract or execute and deliver any
instrument in the name of and on behalf of the corporation, and such authority
may be general or confined to specific instances.

         SECTION 2: No loans shall be contracted on behalf of the corporation
and no evidences of indebtedness shall be issued in its name unless authorized
by a resolution of the Board of Directors. Such authority may be general or
confined to specific instances.

         SECTION 3: All checks, drafts or other orders for the payment of money,
notes or other evidences or indebtedness issued in the name of the corporation
shall be signed by such duly authorized officer of officers, or agent or agents
of the corporation and in such manner as shall from time to time be determined
by resolution of the Board of Directors.


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         SECTION 4: All funds of the corporation not otherwise employed shall be
deposited from time to time to the credit of the corporation in such banks,
trust companies or other depositories as the Board of Directors may select.

                                   ARTICLE VII

                              Certificate of Shares
                              ---------------------

         SECTION 1: Certificates representing shares of the corporation shall be
in such form as shall be determined by the Board of Directors. Such certificates
shall be signed by the President and by the Secretary. All certificates for
shares shall be consecutively numbered or otherwise identified. The name and
address of the person to whom the shares represented thereby are issued, with
the number of shares and date of issue, shall be entered on the stock transfer
books of the corporation. All certificates surrendered to the corporation for
transfer shall be cancelled and no new certificate shall be issued until the
former certificate for a like number of shares shall have been surrendered and
cancelled, except in case of a lost, destroyed or mutilated certificate, a new
one may be issued thereof upon such terms and indemnity to the corporation as
the Board of Directors may prescribe.

         SECTION 2: Transfer of shares of the corporation shall be made only on
the stock transfer books of the corporation by the holder of record thereof or
by his legal representative, who shall furnish proper evidence of authority to
transfer, or by his attorney authorized by power of attorney duly executed and
filed with the Secretary of the corporation, and on surrender for cancellation
of the certificate for such shares. The person in whose name shares stand on the
books of the corporation shall be deemed by the corporation to be the owner
thereof for all purposes, unless otherwise notified by such person in writing.


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                                  ARTICLE VIII

                                   Fiscal Year
                                   -----------

         SECTION 1: The fiscal year of the corporation shall be fixed by
resolution of the Board of Directors.

                                   ARTICLE IX

                                      Seal
                                      ----

         SECTION 1: The corporate seal shall have inscribed thereon the name of
the corporation, the year of its organization and the words "Corporate Seal,
Delaware." The seal may be used by causing it or a facsimile thereof to be
impressed or affixed or reproduced or otherwise.

                                    ARTICLE X

                                   Amendments
                                   ----------

         SECTION 1: Those By-Laws may be amended by a majority vote of all stock
issued and outstanding an entitled to vote at any annual or special meeting of
the stockholders, provided notice of intention to amend shall have been
contained in the notice of the meeting.

         SECTION 2: The Board of Directors, by a majority vote of the entire
Board at any meeting, may amend these By-Laws, including By-Laws adopted by the
stockholders.


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                                   ARTICLE XI

                    Indemnification of Directors and Officers
                    -----------------------------------------

         SECTION 1: Every person who was or is a party to, or is threatened to
be made a part to, or is involved in any action, suit or proceedings, whether
civil, criminal, administrative or investigative, by reason of the fact that he
or a person of whom he is the legal representative is or was a director or
officer of the corporation or is or was serving at the request of the
corporation as a director or officer of another corporation, or as its
representative in a partnership, joint venture, trust or other enterprise, shall
be indemnified and held harmless to the fullest extent legally permissible under
the laws of the State of Delaware from time to time against all expenses,
liability and loss, including attorneys' fees, judgments, fines and amounts paid
in settlement, reasonably incurred or suffered by him in connection therewith.
Such right of indemnification shall be a contract right which may be enforced in
any manner desired by such person.


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