EXHIBIT 4.1

                             SENTIGEN HOLDING CORP.

                           ---------------------------

                             SUBSCRIPTION AGREEMENT

                           ---------------------------






                                  INSTRUCTIONS

                IMPORTANT: PLEASE READ CAREFULLY BEFORE SIGNING.
           SIGNIFICANT REPRESENTATIONS ARE CONTAINED IN THIS DOCUMENT.

               THERE ARE TWO AGREEMENTS ATTACHED. BOTH AGREEMENTS
                  NEED TO BE COMPLETED AND EXECUTED AS FOLLOWS:

1. Fill in the missing information on Page 1.

2. Individual Investors must complete Question 7.7 and sign the signature page
   on Pages 4 and 8.

3. Entity Investors must complete Question 7.8 (certain persons affiliated with
   the entity may be required to complete Question 7.7 and sign on page 4) and
                       sign the signature page on Page 9.

                       DELIVER THE EXECUTED AGREEMENTS TO:

                            GRAUBARD MOLLEN & MILLER
                                600 THIRD AVENUE
                            NEW YORK, NEW YORK 10016
                        ATTENTION: DANIELLE GHORRA, ESQ.

                ALONG WITH PAYMENT FOR THE SHARES SUBSCRIBED FOR.




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                          Print Name of Subscriber ----------------------------


                             SUBSCRIPTION AGREEMENT

 IMPORTANT: Please refer to Schedule 1 commencing on page 10 when reviewing this
      document. The Schedule is incorporated herein and made a part hereof.

The Company and the Investor hereby agree as follows:

         1. Subscription for Shares. I (sometimes referred to herein as the
"Investor") hereby subscribe for and agree to purchase $__________ of the
securities being offered by SENTIGEN HOLDING CORP. ("Sentigen" or "Company")
described on Schedule 1 hereto ("Shares") upon the terms and conditions of the
offering ("Offering") described in this Agreement and Schedule 1. Graubard
Mollen & Miller ("GM&M" or the "Escrow Agent") is acting as the Escrow Agent for
the Offering.

         2. Offering Period.  The Shares are currently being offered by the
Company through the date set forth on Schedule 1 ("Termination Date").

         3. Investor Delivery of Documents and Payment. I hereby tender to GM&M,
as Escrow Agent for the Company (i) the full purchase price by check or wire in
accordance with the instructions set forth on Schedule 1 and (ii) two manually
executed copies of this Subscription Agreement. Prior to the earlier of a
Closing (as defined in Section 5 hereof) or the Termination Date, my check or
wire transfer will be held by GM&M in a non-interest bearing escrow account
subject to the terms and conditions herein and in the escrow agreement between
GM&M, as escrow agent, and the Company. If the Company does not receive and
accept the minimum subscriptions required to have a Closing as set forth on
Schedule 1 by the Termination Date, my payment will be returned to me without
interest or deduction.

         4. Acceptance or Rejection of Subscription. The Company has the right
to reject this subscription for Shares, in whole or in part for any reason and
at any time prior to the Closing, notwithstanding prior receipt by me of notice
of acceptance of my subscription. In the event of the rejection of this
subscription, my payment will be returned promptly to me without interest or
deduction and this Subscription Agreement will have no force or effect. The
Shares subscribed for herein will not be deemed issued to or owned by me until
two copies of this Subscription Agreement have been executed by me and
countersigned by the Company and the Closing with respect to my subscription has
occurred.

         5. Closing and Delivery of Shares. The closing of the Offering
("Closing") may occur at the office of GM&M at any time prior to the Termination
Date and after the sale by the Company of the required amount as set forth on
Schedule 1, as determined by the Company. In the event my subscription is
accepted and there is a Closing, my payment will be released to the Company and
the certificates representing the Shares will be delivered promptly to me, along
with a fully executed version of this Agreement.

         6. Offering to Accredited Investors. This Offering is limited to
accredited investors as defined in Section 2(15) of the Securities Act of 1933,
as amended ("Securities Act"), and Rule 501 promulgated thereunder, and is being
made without registration under the Securities Act in reliance upon the
exemptions contained in Sections 3(b), 4(2) and/or 4(6) of the Securities Act
and applicable state securities laws. As indicated by my responses on page 4 or





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5 hereof, the Investor is an "accredited investor" within the meaning of Section
2(15) of the Securities Act and Rule 501 promulgated thereunder.

         7.  Investor Representations and Warranties.  I acknowledge, represent
and warrant to the Company as follows:

             7.1 Obligations of the Company and the Investor. The Company
has no obligation to me other than as set forth in this Agreement, including but
not limited to the obligations described in Section 7.1 at Schedule 1. I have
read and agree to the restrictions set forth in Section 7.1 of Schedule 1. I am
aware that, except for any rescission rights that may be provided under
applicable laws, I am not entitled to cancel, terminate or revoke this
subscription, and any agreements made in connection herewith will survive my
death or disability. In order to induce the Company to issue and sell the Shares
to me, I represent and warrant that the information relating to me stated herein
is true and complete as of the date hereof and will be true and complete as of
the date on which my purchase of Shares becomes effective. If, prior to the
final consummation of the offer and sale of the Shares, there should be any
change in such information or any of such information becomes incorrect or
incomplete, I agree to notify the Company and supply the Company promptly with
corrective information.

              7.2 Information About the Company.

                  (a)  I have read the Confidential Private Placement Memorandum
dated September 29, 2000 relating to the Offering ("Memorandum") and all
exhibits listed therein and fully understand the Memorandum, including the
Section entitled "Risk Factors" and its exhibits, including any business plans
or financial projections of the Company. I have been given access to full and
complete information regarding the Company and have utilized such access to my
satisfaction for the purpose of verifying the information included in the
Memorandum and exhibits thereto, and I have either met with or been given
reasonable opportunity to meet with officers of the Company for the purpose of
asking reasonable questions of such officers concerning the terms and conditions
of the offering of the Shares and the business and operations of the Company and
all such questions have been answered to my full satisfaction. I have also been
given an opportunity to obtain any additional relevant information to the extent
reasonably available to the Company. I have received all information and
materials regarding the Company that I have reasonably requested. After my
reading of the materials about the Company, I understand that there is no
assurance as to the future performance of the Company. I have not relied on
information other than what can be found in the Memorandum in making my decision
to invest in the Shares.

                  (b)  I have received no representation or warranty from the
Company or any of its respective officers, directors, employees or agents in
respect of my investment in the Company. I am not participating in the offer as
a result of or subsequent to: (i) any advertisement, article, notice or other
communication published in any newspaper, magazine or similar media or broadcast
over television, radio or the Internet or (ii) any seminar or meeting whose
attendees have been invited by any general solicitation or general advertising.

          7.3    Speculative Investment. I am aware that the Shares are a
speculative investment that involves a high degree of risk including, but not
limited to, the risk of losses from operations of the Company and the total loss
of my investment. I have such knowledge and experience in financial and business
matters as to be capable of evaluating the merits and risks of an investment in
the Shares and have obtained, in my judgment, sufficient information from the
Company to evaluate the merits and risks of an investment in the Company. I have
not utilized any person as my purchaser representative (as defined in Regulation


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D) in connection with evaluating such merits and risks and have relied solely
upon my own investigation in making a decision to invest in the Company. I have
been urged to seek independent advice from my professional advisors relating to
the suitability of an investment in the Company in view of my overall financial
needs and with respect to the legal and tax implications of such investment. I
believe that the investment in the Shares is suitable for me based upon my
investment objectives and financial needs, and I have adequate means for
providing for my current financial needs and contingencies and have no need for
liquidity with respect to my investment in the Company. The investment in the
Company does not constitute all or substantially all of my investment portfolio.

             7.4   Restrictions on Transfer. I understand that (i) the Shares
have not been registered under the Securities Act or the securities laws of
certain states in reliance on specific exemptions from registration, (ii) no
securities administrator of any state or the federal government has recommended
or endorsed this Offering or made any finding or determination relating to the
fairness of an investment in the Company, and (iii) the Company is relying on my
representations and agreements for the purpose of determining whether this
transaction meets the requirements of the exemptions afforded by the Securities
Act and certain state securities laws. I acknowledge that there is no assurance
that the Company will file any Registration Statement for the Shares I am
purchasing, that such Registration Statement, if filed, will be declared
effective or, if declared effective, that the Company will be able to keep it
effective until I sell the Shares registered thereon.

                  7.5 Limited Market for Shares. I am purchasing the Shares for
my own account for investment and not with a view to, or for sale in connection
with, any subsequent distribution of the Shares, nor with any present intention
of selling or otherwise disposing of all or any part of the Shares. I understand
that there is a limited market at present and there may not be any market in the
future for the Shares. I agree that (i) the purchase of the Shares is a
long-term investment, (ii) I may have to bear the economic risk of investment
for an indefinite period of time because the Shares have not been registered
under the Securities Act and may never be registered and, cannot be resold,
pledged, assigned, or otherwise disposed of unless they are subsequently
registered under the Securities Act and under applicable securities laws of
certain states or an exemption from such registration is available. I understand
that the Company is under no obligation to register the Shares, except as may be
set forth in Section 7.1 of Schedule 1, or to assist me in complying with any
exemption from such registration under the Securities Act or any state
securities laws. I hereby authorize the Company to place a legend denoting the
restrictions on the certificates representing the Shares.

                  7.6 Entity Authority. If the Investor is a corporation,
partnership, company, trust, employee benefit plan, individual retirement
account, Keogh Plan, or other tax-exempt entity, it is authorized and qualified
to become an investor in the Company and the person signing this Subscription
Agreement and Investor Information Statement on behalf of such entity has been
duly authorized by such entity to do so.

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       7.7 Accredited Investor Status For Individuals. (INVESTORS
THAT ARE CORPORATIONS, LIMITED LIABILITY COMPANIES, PARTNERSHIPS, REVOCABLE
TRUSTS, IRREVOCABLE TRUSTS, EMPLOYEE BENEFIT PLAN TRUSTS AND INDIVIDUAL
RETIREMENT ACCOUNTS SHOULD IGNORE THE FOLLOWING QUESTIONS AND PROCEED TO SECTION
7.8).

         (a) I am an accredited investor within the meaning of Section
2(15) of the Securities Act and Rule 501 promulgated thereunder because (check
any boxes that apply):

               |_|  My individual annual income during each of the two most
                    recent years exceeded $200,000 and I expect my annual income
                    during the current year will exceed $200,000.

               |_|  If I am married, my joint annual income with my spouse
                    during each of the two most recent years exceeded $300,000
                    and I expect my joint annual income with my spouse during
                    the current year will exceed $300,000.

               |_|  My individual or joint (together with my spouse) net worth
                    (including my home, home furnishings and automobiles)
                    exceeds $1,000,000.

          (b)   The aggregate value of my assets is approximately $___________.

          (c)   My aggregate liabilities are approximately $___________.

          (d)   My current and expected income is:


                 YEAR                        INCOME
                 ----                        ------
           2000 (estimated)             $

             1999 (Actual)              $

             1998 (Actual)              $


         Individual Investors may skip to Section 7.9 on page 6. Each person
associated with an Entity Investor who is required under Section 7.8 to
separately complete the questions in this Section 7.7 must sign the below
confirmation:

                  I hereby confirm the answers to Section 7.7 are true and
                  correct in all respects as of the date hereof and will be on
                  the date of the purchase of Shares.

                  Executed this ____ day of ________, 200__.

                  Signature:
                                    -------------------------------------
                  Print Name:
                                    -------------------------------------

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           7.8    Accredited Investor Status for Entities.  (INVESTORS WHO ARE
INDIVIDUALS SHOULD IGNORE THESE QUESTIONS.)

                  (a)    The entity is a (check applicable box):

                    |_|  Corporation

                    |_|  Limited Liability Company

                    |_|  Partnership

                    |_|  Revocable Trust

                    |_|  Irrevocable Trust (if the Investor is an Irrevocable
                         Trust, a supplemental questionnaire must be completed
                         by the person directing the decision for the trust.
                         Please contact Danielle Ghorra, Esq. at (212) 818-8877
                         for a copy of such supplemental questionnaire.)

                    |_|  Employee Benefit Plan Trust

                    |_|  Individual Retirement Account (If you are an IRA, skip
                         (b))

                  (b)     Check all boxes which apply:

                    |_|  The Entity was not formed for the specific purpose of
                         investing in the Company

                    |_|  The Entity has total assets in excess of $5 million
                         dollars

                    |_|  For Employee Benefit Plan Trusts Only: The decision to
                         invest in the Company was made by a plan fiduciary, as
                         defined in Section 3(21) of ERISA, who is either a
                         bank, insurance company or registered investment
                         advisor.

                 (c) If you did not check the first two of the three boxes in
Question (b) or if the Entity is an Individual Retirement Account, a
Self-directed Employee Benefit Plan Trust or an Irrevocable Trust, list the name
of each person who:

                    (i)  owns an equity interest in the Entity (i.e., each
                         shareholder if the Entity is a corporation, each member
                         if the Entity is a limited liability company and each
                         partner if the Entity is a partnership); or

                    (ii) is a grantor for the revocable trust or Individual
                         Retirement Account; or

                    (iii) is the person making the investment decision for a
                         self-directed Employee Benefit Plan Trust; or

                    (iv) is the person making the investment decisions for an
                         Irrevocable Trust.

    ---------------------------               --------------------------

    ---------------------------               --------------------------

       EACH PERSON LISTED ABOVE MUST SEPARATELY COMPLETE AND SUBMIT TO THE
            COMPANY THE ANSWERS TO QUESTION 7.7 AND SIGN THE WRITTEN
                     CONFIRMATION AT THE END OF SECTION 7.7.


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                  7.9 No Offer Until Determination of Suitability. I acknowledge
that any delivery to me of the documents relating to the Offering of the Shares
prior to the determination by the Company of my suitability will not constitute
an offer of the Shares until such determination of suitability is made.

                  7.10 For Florida Residents. The Shares have not been
registered under the Securities Act of 1933, as amended, or the Florida
Securities Act, by reason of specific exemptions thereunder relating to the
limited availability of the Offering. The Shares cannot be sold, transferred, or
otherwise disposed of to any person or entity unless subsequently registered
under the Securities Act of 1933, as amended, or the Securities Act of Florida,
if such registration is required. Pursuant to Section 517.061(11) of the Florida
Securities Act, when sales are made to five (5) or more persons in Florida, any
sale made pursuant to Subsection 517.061(11) of the Florida Securities Act will
be voidable by such Florida purchaser either within three days after the first
tender of consideration is made by the purchaser to the issuer, an agent of the
issuer, or an escrow agent, or within three days after the availability of the
privilege is communicated to such purchaser, whichever occurs later. In
addition, as required by Section 517.061(11)(a)(3), Florida Statutes and by Rule
3-500.05(a) thereunder, if I am a Florida resident I may have, at the offices of
the Company, at any reasonable hour, after reasonable notice, access to the
materials set forth in the Rule that the Company can obtain without unreasonable
effort or expense.

         8. Indemnification. I hereby agree to indemnify and hold harmless the
Company and its officers, directors, stockholders, employees, agents, and
attorneys against any and all losses, claims, demands, liabilities, and expenses
(including reasonable legal or other expenses incurred by each such person in
connection with defending or investigating any such claims or liabilities,
whether or not resulting in any liability to such person or whether incurred by
the indemnified party in any action or proceeding between the indemnitor and
indemnified party or between the indemnified party and any third party) to which
any such indemnified party may become subject, insofar as such losses, claims,
demands, liabilities and expenses (a) arise out of or are based upon any untrue
statement or alleged untrue statement of a material fact made by me and
contained herein, or (b) arise out of or are based upon any breach by me of any
representation, warranty, or agreement made by me contained herein.

         9. Severability; Remedies.  In the event any parts of this Subscription
Agreement are found to be void, the remaining provisions of this Subscription
Agreement are nevertheless binding with the same effect as though the void parts
were deleted.

         10. Governing Law and Jurisdiction. This Subscription Agreement will be
deemed to have been made and delivered in New York City and will be governed as
to validity, interpretation, construction, effect and in all other respects by
the internal laws of the State of New York. Each of the Company and the Investor
hereby (i) agrees that any legal suit, action or proceeding arising out of or
relating to this Subscription Agreement will be instituted exclusively in New
York State Supreme Court, County of New York, or in the United States District
Court for the Southern District of New York, (ii) waives any objection to the
venue of any such suit, action or proceeding and the right to assert that such
forum is not a convenient forum for such suit, action or proceeding, (iii)
irrevocably consents to the jurisdiction of the New York State Supreme Court,
County of New York, and the United States District Court for the Southern
District of New York in any such suit, action or proceeding, (iv) agrees to
accept and acknowledge service of any and all process that may be served in any
such suit, action or proceeding in New York State Supreme Court, County of New
York or in the United States District Court for the Southern District of New
York and (v) agrees that service of process upon it mailed by certified mail to
its address set forth on my signature page will be deemed in every respect
effective service of process upon it in any suit, action or proceeding.



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          11. Counterparts. This Subscription Agreement may be executed in one
or more counterparts, each of which will be deemed an original but all of which
together will constitute one and the same instrument. The execution of this
Subscription Agreement may be by actual or facsimile signature.

          12. Benefit.  This Subscription Agreement is binding upon and inures
to the benefit of the parties hereto and their respective heirs, executors,
personal representatives, successors and assigns.

         13. Notices. All notices, offers, acceptance and any other acts under
this Subscription Agreement (except payment) must be in writing, and is
sufficiently given if delivered to the addressees in person, by overnight
courier service, or, if mailed, postage prepaid, by certified mail (return
receipt requested), and will be effective three days after being placed in the
mail if mailed, or upon receipt or refusal of receipt, if delivered personally
or by courier or confirmed telecopy, in each case addressed to a party. All
communications to me should be sent to my preferred address on the signature
page hereto. All communications to the Company should be sent to the addresses
set forth on Schedule 1. Each party may designate another address by notice to
the other parties.

         14. Oral Evidence. This Subscription Agreement constitutes the entire
agreement between the parties with respect to the subject matter hereof and
supersedes all prior oral and written agreements between the parties hereto with
respect to the subject matter hereof. This Subscription Agreement may not be
changed, waived, discharged, or terminated orally, but rather, only by a
statement in writing signed by the party or parties against which enforcement or
the change, waiver, discharge or termination is sought.

         15. Section Headings.  Section headings herein have been inserted for
reference only and will not be deemed to limit or otherwise affect, in any
matter, or be deemed to interpret in whole or in part, any of the terms or
provisions of this Subscription Agreement.

         16. Survival of Representations, Warranties and Agreements.  The
representations, warranties and agreements contained herein will survive the
delivery of, and the payment for, the Shares.

         17. Acceptance of Subscription.  The Company may accept this
Subscription Agreement at any time for all or any portion of the Shares
subscribed for by executing a copy hereof as provided and notifying me within a
reasonable time thereafter.



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         SIGNATURE PAGE FOR INDIVIDUAL INVESTORS - COMPLETE ALL INFORMATION
         ---------------------------------------

Name: ___________________     Name of  Joint Investor (if any): _______________

Residence Address:  ___________________________________________________________

Telephone:  (H) ___________________ (W) _____________________ Fax _____________

Occupation: _________________________   Employer: _____________________________

Business Address: _____________________________________________________________

Send communications to:

                        |_|    Home      |_|    Office        |_|    E-Mail:

                        E-mail address: ____________________________________

Age:  _______________

Social Security Number:  ____________________

Check manner in which Shares are to be held:

|_|   Individual       |_|    Tenants in     |_|    Joint Tenants with
      Ownership               Common                Right of Survivorship
                                                    (both parties must sign)
|_|   Community                              |_|    Other (please indicate)
      Property                                      __________________


ALL INVESTORS MUST SIGN AND PRINT        The foregoing subscription is accepted
NAME BELOW:                              and the Company hereby agrees to be
                                         bound by its terms.
Signature:  _________________________    SENTIGEN HOLDING CORP.
Print Name: _________________________
Signature:  _________________________    By:__________________________________
Print Name:___________________________      Name:
                                            Title:
                                            Date:




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SIGNATURE PAGE FOR ENTITY INVESTORS - COMPLETE ALL INFORMATION
-----------------------------------

Name of Entity: ______________________________________________________________

Address of Principal Office:  ________________________________________________

Telephone:   ___________________          Fax:  ___________________

Taxpayer Identification Number:  ______________________

Check type of Entity:


|_|  Employee Benefit    |_| Limited      |_|  General      |_|  Individual
     Plan Trust              Partnership       Partnership       Retirement
                                                                 Account

|_|  Limited Liability   |_| Trust        |_|  Corporation  |_|  Other (please
     Company                                                     indicate)
                                                                  _____________

Date of Formation or incorporation: ___________   State of Formation or
                                                  incorporation: __________

Describe the business of the Entity: _______________________________________


List the names and positions of the executive officers, managing members,
partners or trustees authorized to act with respect to investments by the Entity
generally and specify who has the authority to act with respect to this
investment.

Name                Position           Authority for this investment (yes or no)
________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________


ALL INVESTORS MUST SIGN AND PRINT     The foregoing subscription is accepted and
NAME BELOW:                           the Company hereby agrees to be bound by
                                      its terms.
                                      SENTIGEN HOLDING CORP.
----------------------------------
Signature of Authorized Signatory:
Name:
Title:
                                      By:__________________________________
                                         Name:
                                         Title:
                                         Date:
<PAGE>



                                   SCHEDULE 1

1.   Subscription. SENTIGEN HOLDING CORP. ("Sentigen" or the "Company") is
     offering 830,000 shares of common stock, par value $.01 per share
     ("Shares") of the Company, at a purchase price of $6.00 per Share.

2.   Offering Period. The Company is offering the Shares until the earlier of
     (i) the date by which all the Shares being offered are sold, or (ii) thirty
     (30) days after the date of the Memorandum, unless such latter date is
     extended, without notice to the subscriber, by the Company to a date not
     later than an additional thirty (30) days thereafter ("Termination Date").

3.   Purchase. If you are tendering a check, make it payable to "Graubard Mollen
     & Miller, as attorneys for Sentigen Holding Corp." If you are paying by
     wire transfer, please instruct your bank to wire funds to:

                           Bankers Trust Company
                           280 Park Avenue
                           New York, New York  10017
                           ABA Routing Number: 021001033
                           Attn.:  Florence Blanchard

                           For credit to:
                           Graubard Mollen & Miller
                           Attorney Trust Account - IOLA Funds
                           Account No. 35228777

                  All wires should stipulate the name of the subscriber,
including those sent by brokers or other agents.

                  Prior to wiring funds, please contact Rosemary Perdue at (212)
818-8745 and give her the following information:

                  (1)      when the money will be wired;
                  (2)      the name and address of the bank from which the
                           money is being wired; and
                  (3)      the exact dollar amount being wired.

4.   Not applicable.

5.   Closing. The Offering is being made on an "all or none" basis. In order for
     the Offering to close, the Company must receive and accept subscriptions
     for 830,000 Shares ($4,980,000).

6.   Not applicable.

7.1      Obligations of the Company and the Investor

         A.    Registration Rights.

               (1) Company's Obligation to Register. Within six months after the
          date of the Closing, the Company shall file a Registration Statement
          ("Registration Statement") under the

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         Securities Act of 1933 ("Securities Act") with the Securities and
         Exchange Commission ("SEC") registering for resale the Shares purchased
         in the Offering. The Company shall use its best efforts to have the
         Registration Statement declared effective by the SEC and be kept
         current and effective until all the Shares registered thereunder are
         sold or can be sold freely under an appropriate exemption, without
         limitation.

                  (2) Covenants. If and whenever the Company is required by the
         provisions of this Agreement to effect the registration of any of the
         Shares under the Securities Act, the Company shall:

                           (a) file with the Commission a Registration Statement
         with respect to such Shares and use its best efforts to cause that
         Registration Statement to become effective as soon as possible;

                           (b) use its best efforts to prepare and file with the
         Commission any amendments and supplements to the Registration Statement
         and the prospectus included in the Registration Statement as may be
         necessary to comply with the provisions of the Securities Act
         (including the anti-fraud provisions thereof), and to keep the
         Registration Statement effective until the earlier of the date which
         all of the Shares are sold and the date that the Shares may be sold
         pursuant to Rule 144 without restrictions;

                           (c) as expeditiously as possible furnish to each
         holder of the Shares sold in this Offering ("Holder") such reasonable
         numbers of copies of the Prospectus which forms a part of the
         Registration Statement, including any preliminary Prospectus, in
         conformity with the requirements of the Securities Act, and such other
         documents as such Investor may reasonably request in order to
         facilitate the public sale or other disposition of the Shares owned by
         such Investor;

                           (d) as expeditiously as possible use its best efforts
         to register or qualify the Registrable Securities covered by the
         Registration Statement under the securities or Blue Sky laws of such
         states as the Investors shall reasonably request, and do any and all
         other acts and things that may be necessary or desirable to enable the
         Investors to consummate the public sale or other disposition in such
         states of the Registrable Securities owned by the Investor; provided,
         however, that the Company shall not be required in connection with this
         paragraph to qualify as a foreign corporation or execute a general
         consent to service of process in any jurisdiction;

                           (e) as expeditiously as possible, cause all such
         Shares to be listed on each securities exchange or automated quotation
         system on which similar securities issued by the Company are then
         listed;

                           (f) promptly arrange the services of a transfer agent
         and registrar for all such Registrable Securities not later than the
         effective date of such registration statement;

                           (g) as expeditiously as possible, notify each
         Investor, promptly after it shall receive notice thereof, of the time
         when such Registration Statement has become effective or a supplement
         to any Prospectus forming a part of such Registration Statement has
         been filed; and

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                           (h) as expeditiously as possible following the
         effectiveness of such Registration Statement, notify each seller of
         such Shares of any request by the Commission for the amending or
         supplementing of such Registration Statement or Prospectus.

                           If the Company has delivered a Prospectus to the
         Investors and after having done so the Prospectus is amended to comply
         with the requirements of the Securities Act, the Company shall promptly
         notify the Investors and, if requested, the Investors shall immediately
         cease making offers of Shares and return all Prospectuses to the
         Company or affix a sticker to the Prospectuses which is provided by the
         Company. If returned, the Company shall promptly provide the Investors
         with revised Prospectuses and, following receipt of the revised
         Prospectuses, the Investors shall be free to resume making offers of
         the Shares.

                           (4) Fees and Expenses. In any registration statement
         in which Shares are included pursuant to this Section, the Company
         shall bear all expenses and pay all fees incurred in connection
         therewith, excluding underwriting discounts and commissions payable
         with respect to the Shares and the fees and expenses of any
         professionals engaged by the Holders, but including the expenses of
         providing a reasonable number of copies of the prospectus contained
         therein to the Holders.

                           (5) Indemnification by Company. The Company shall
         indemnify the Holders of the Shares to be sold pursuant to any
         registration statement hereunder, the officers and directors of each
         Holder and each person, if any, who controls such Holders within the
         meaning of Section 15 of the Securities Act or Section 20(a) of the
         Securities Exchange Act of 1934, as amended ("Exchange Act"), or any
         state securities law or regulation, against all loss, claim, damage,
         expense or liability (including all reasonable attorneys' fees and
         other expenses reasonably incurred in investigating, preparing or
         defending against any claim whatsoever incurred by the indemnified
         party in any action or proceeding between the indemnitor and
         indemnified party or between the indemnified party and any third party
         or otherwise) to which any of them may become subject under the
         Securities Act, the Exchange Act or any other statute or at common law
         or otherwise under the laws of foreign countries, arising from such
         registration statement or based upon any untrue statement or alleged
         untrue statement of a material fact contained in (i) any preliminary
         prospectus, the registration statement or prospectus (as from time to
         time each may be amended and supplemented); (ii) any post-effective
         amendment or amendments or any new registration statement and
         prospectus in which is included the Shares; or (iii) any application or
         other document or written communication (collectively called
         "application") executed by the Company or based upon written
         information furnished by the Company in any jurisdiction in order to
         qualify the Shares under the securities laws thereof or filed with the
         Securities and Exchange Commission, any state securities commission or
         agency, Nasdaq or any securities exchange; or the omission or alleged
         omission therefrom of a material fact required to be stated therein or
         necessary to make the statements therein, in light of the circumstances
         under which they were made, not misleading, unless such statement or
         omission is made in reliance upon, and in conformity with, written
         information furnished to the Company by and with respect to such
         registered Holders ("Purchaser Information") expressly for use in any
         preliminary prospectus, the registration statement or prospectus, or
         any amendment or supplement thereof, or in any application, as the case
         may be, or unless the indemnities failed to deliver a final prospectus
         in which the material misstatement or omission was corrected. The
         Company agrees promptly to notify such Investors of the commencement of
         any litigation or proceedings against the Company or any of its
         officers, directors or controlling persons in connection with the issue
         and sale or resale of the Shares or in connection with the registration
         statement or prospectus.

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<PAGE>


                           (6) Elimination of Registration Rights.
         Notwithstanding anything to the contrary in Sections 1 and 2 above, no
         Holder of Shares shall be entitled to have such securities registered
         under the Securities Act in accordance with the provisions of such
         Sections if, (a) in the opinion of counsel to the Company, they may be
         sold without restriction pursuant to Rule 144(k) promulgated under the
         Securities Act and any restrictive legends under the Securities Act are
         removed from the certificates representing such securities and any stop
         transfer order for such certificates is removed; or (b) the Holder has
         not complied with the Company's request for information typically
         included in registration statements with respect to the sellers of
         securities and their ownership of securities.

                           (7) Successors and Assigns. The registration rights
         granted to the Holders inure to the benefit of all the Holders'
         successors, heirs, pledges, assignees, transferees and purchasers of
         the Shares.

8.-12.   Not applicable.

13.      Notices.  All communications to the Company should be sent to:

                  SENTIGEN HOLDING CORP.
                  580 Marshall Street
                  Phillipsburg, New Jersey 08865
                  Attention: Joseph K. Pagano, President and Chairman
                  Tel.:  (800) 543-6029
                  Fax:  (908)454-4792

         with copies to:

                           Graubard Mollen & Miller
                           600 Third Avenue
                           New York, New York 10016
                           Attention: David Alan Miller, Esq.
                           Tel: (212) 818-8661
                           Fax:  (212) 818-8881

14.-17.  Not applicable.



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