content: <PAGE>   1
  FORM 144
                                                     OMB APPROVAL
                                                     ------------
                                     OMB Number                          3235-0101
                                     Expires:                      August 31, 2003
                                     Estimated average burden
                                     hours per response                        2.0
  
                                                                 DOCUMENT SEQUENCE
                                                                 NO.
  
                                                                 -----------------
                                                                 CUSIP NUMBER
  
                                                                 -----------------
                                                                 WORK LOCATION
  
                                                                 -----------------
  
                                   UNITED STATES
                         SECURITIES AND EXCHANGE COMMISSION
                               WASHINGTON, D.C. 20549
                                    SEC USE ONLY
  
                        NOTICE OF PROPOSED SALE OF SECURITIES
               PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933
  
  ATTENTION:  Transmit for filing 3 copies of this form concurrently with either
              placing an order with a broker to execute sale or executing a sale
              directly with a market maker.
  <TABLE>
  <S>                                                                             <C>                       <C>
  -----------------------------------------------------------------------------------------------------------------------------------
  1(a) NAME OF ISSUER (Please type or print)                                      (b) IRS IDENT. NO.        (c) S.E.C. FILE NO.
  
  i-STAT CORPORATION                                                              22-2542664                000-19841
  -----------------------------------------------------------------------------------------------------------------------------------
                                                                                                          (e) TELEPHONE NO.
  1(d) ADDRESS OF ISSUER          STREET             CITY         STATE          ZIP CODE       AREA CODE                   NUMBER
                                                                                                -----------------------------------
  104 WINDSOR CENTER DRIVE, EAST WINDSOR, NJ 08520                                                 609                     443-9300
  ------------------------------------------------------------------------------------------------------------------------------------
  2(a) NAME OF PERSON FOR WHOSE ACCOUNT   (b) IRS IDENT. NO.    (c) RELATIONSHIP TO   (d) ADDRESS   STREET   CITY   STATE   ZIPCODE
  THE SECURITIES ARE TO BE SOLD                                  ISSUER
  ------------------------------------------------------------------------------------------------------------------------------------
  WILLIAM P. MOFFITT                      ###-##-####            CHIEF EXECUTIVE       412 RAMSEY ROAD, YARDLEY PA 19067
                                                                 OFFICER
  ------------------------------------------------------------------------------------------------------------------------------------
  </TABLE>
  
   INSTRUCTION: The person filing this notice should contact the issuer to obtain
           the I.R.S. Identification Number and the S.E.C. File Number.
  
  <TABLE>
  <S>            <C>                                                   <C>               <C>                  <C>
  ------------------------------------------------------------------------------------------------------------------------------------
  3(a)           (b)                                                                      (c)                 (d)
  TITLE OF THE                                                         SEC USE ONLY        NUMBER OF SHARES        AGGREGATE
    CLASS OF     NAME AND ADDRESS OF EACH BROKER THROUGH WHOM THE                           OR OTHER UNITS          MARKET
   SECURITIES    SECURITIES ARE TO BE OFFERED OR EACH MARKET MAKER     BROKER-DEALER          TO BE SOLD             VALUE
   TO BE SOLD             WHO IS ACQUIRING THE SECURITIES               FILE NUMBER        (See instr. 3(c))   (See instr. 3(d))
  ------------------------------------------------------------------------------------------------------------------------------------
  COMMON         MERRILL LYNCH & CO., INC.                                                  44,444              $726,659.40 AS OF
  STOCK                                                                                                         CLOSE OF BUSINESS
                                                                                                                JUNE 13, 2001
  ------------------------------------------------------------------------------------------------------------------------------------
  </TABLE>
  
  <TABLE>
  <CAPTION>
  ------------------------------------------------------------------------------------------------------------------------------------
  3(a)           (b)                                                   (e)                 (f)                  (g)
  TITLE OF THE                                                          NUMBER OF SHARES       APPROXIMATE         NAME OF EACH
    CLASS OF     NAME AND ADDRESS OF EACH BROKER THROUGH WHOM THE        OR OTHER UNITS       DATE OF SALE          SECURITIES
   SECURITIES    SECURITIES ARE TO BE OFFERED OR EACH MARKET MAKER         OUTSTANDING      (See instr. 3(f))        EXCHANGE
   TO BE SOLD             WHO IS ACQUIRING THE SECURITIES               (See instr. 3(e))    (MO.  DAY  YR.)     (See instr. 3(g))
  ------------------------------------------------------------------------------------------------------------------------------------
  <S>            <C>                                                   <C>                 <C>                  <C>
  COMMON         MERRILL LYNCH & CO., INC.                             18,531,128          June 18, 2001        NASDAQ
  STOCK                                                                                    THROUGH
                                                                                           NOVEMBER 1,
                                                                                           2001
  ------------------------------------------------------------------------------------------------------------------------------------
  </TABLE>
  
  INSTRUCTIONS:
  1. (a) Name of issuer
     (b) Issuer's I.R.S. Identification Number
     (c) Issuer's S.E.C. file number, if any
     (d) Issuer's address, including zip code
     (e) Issuer's telephone number, including area code
  
  2. (a) Name of person for whose account the securities are to be sold
     (b) Such person's I.R.S. identification number, if such person is
         an entity
     (c) Such person's relationship to the issuer (e.g., officer,
         director, 10% stockholder, or member of immediate family of any of the
         foregoing)
     (d) Such person's address, including zip code
  
  3. (a) Title of the class of securities to be sold
     (b) Name and address of each broker through whom the securities are
         intended to be sold
     (c) Number of shares or other units to be sold (if debt securities, give
         the aggregate face amount)
     (d) Aggregate market value of the securities to be sold as of a
         specified date within 10 days prior to the filing of this notice
     (e) Number of shares or other units of the class outstanding, or if
         debt securities the face amount thereof outstanding, as shown by the most
         recent report or statement published by the issuer
     (f) Approximate date on which the securities are to be sold
     (g) Name of each securities exchange, if any, on which the
         securities are intended to be sold
  
  <PAGE>   2
                         TABLE I -- SECURITIES TO BE SOLD
  
     Furnish the following information with respect to the acquisition of the
  securities to be sold and with respect to the payment of all or any part of the
                 purchase price or other consideration therefor:
  
  <TABLE>
  <CAPTION>
  ------------------------------------------------------------------------------------------------------------------------------------
                                                            Name of Person from
                                                            Whom Acquired
   Title of     Date you       Nature of                    (If gift, also give        Amount of               Date of    Nature of
   the Class    Acquired       Acquisition Transaction      date donor acquired)       Securities Acquired     Payment    Payment
  ------------------------------------------------------------------------------------------------------------------------------------
  <S>           <C>            <C>                          <C>                        <C>                     <C>        <C>
  COMMON        SEE            EXERCISE OF STOCK OPTIONS    i-STAT CORPORATION         44,444
  STOCK         "REMARKS"
                SECTION
                BELOW
  ------------------------------------------------------------------------------------------------------------------------------------
  </TABLE>
  
  INSTRUCTIONS:
  
  1.  If the securities were purchased and full payment therefor was not made in
      cash at the time of purchase, explain in the table or in a note thereto the
      nature of the consideration given. If the consideration consisted of any
      note or other obligation, or if payment was made in installments describe
      the arrangement and state when the note or other obligation was discharged
      in full or the last installment paid.
  
  2.  If within two years after the acquisition of the securities the person for
      whose account they are to be sold had any short positions, put or other
      option to dispose of securities referred to in paragraph (d)(3) of Rule
      144, furnish full information with respect thereto.
  
  ================================================================================
  
                TABLE II -- SECURITIES SOLD DURING THE PAST 3 MONTHS
  
  Furnish the following information as to all securities of the issuer sold during
  the past 3 months by the person for whose account the securities are to be sold.
  
  <TABLE>
  <CAPTION>
  ------------------------------------------------------------------------------------------------------------------------------------
                                                                                                Amount
                                                                                                  of
  Name and Address of Seller               Title of Securities Sold           Date of Sale   Securities Sold         Gross Proceeds
  ------------------------------------------------------------------------------------------------------------------------------------
  <S>                                      <C>                                <C>            <C>                     <C>
  WILLIAM P. MOFFITT                       COMMON STOCK                       ALL TRADING     30,556                 $536,856.05
  412 RAMSEY ROAD                                                             DAYS FROM
  YARDLEY PA 19067                                                            3-21-01 TO
                                                                              6-15-01
  ------------------------------------------------------------------------------------------------------------------------------------
  
  </TABLE>
  REMARKS:
  
  The shares covered by this Form 144 (the "Shares") are being acquired upon the
  exercise of a stock option granted on December 20, 1991 and are being sold
  pursuant to a Rule 10b5-1 sales plan dated February 26, 2001 (the "Plan"), and
  the representation below regarding the seller's knowledge of material
  information speaks as of that plan adoption date.
  
  The object of the Plan is to generate enough cash to enable the seller to bear
  the costs of exercising additional stock options, beyond those contemplated by
  the Plan, that are expiring within one year.  The seller has no intention at
  this time to sell the shares underlying such additional stock options.
  
  The Plan has been structured to permit an orderly sale over an extended period
  of time, without focusing a sale of all of the Shares within one of the limited
  trading windows available to officers of the issuer.  The sale of the Shares
  should in no way be viewed as a reflection of the opinion of the undersigned
  with respect to the business, condition or prospects of the issuer.
  
  Shares will be sold under the Plan only when the previous day's closing bid
  price per Share (the "Market Price") is at a sufficiently high level to cover
  the exercise price and income taxes associated with the exercise of the options
  which give rise to the Shares.  The Shares will be sold according to the
  following instructions: while the Shares trade at or below a certain Market
  Price, no Shares will be sold; while the Shares trade at a Market Price that is
  within a certain range, only such number of Shares will be sold per trading day
  as equals the greater of (a) 500 shares or (b) the total remaining Shares to be
  sold divided by the number of trading days up to and including November 1, 2001;
  and while the Shares trade at or above a certain Market Price, as many Shares as
  possible will be sold.
  
  INSTRUCTIONS:
  See the definition of "person" in paragraph (a) of Rule 144.  Information is to
  be given not only as to the person for whose account the securities are to be
  sold but also as to all other persons included in that definition.  In addition,
  information shall be given as to sales by all persons whose sales are required
  by paragraph (e) of Rule 144 to be aggregated with sales for the account of the
  person filing this notice.
  
  ATTENTION:
  The person for whose account the securities to which this notice relates are to
  be sold hereby represents by signing this notice that he does not know any
  material adverse information in regard to the current and prospective operations
  of the Issuer of the securities to be sold which has not been publicly
  disclosed.
  
       June 18, 2001                             /s/ WILLIAM P. MOFFITT
  -----------------------                        -----------------------
      DATE OF NOTICE                                   (SIGNATURE)
  
   The notice shall be signed by the person for whose account the securities are
      to be sold.  At least one copy of the notice shall be manually signed.
      Any copies not manually signed shall bear typed or printed signatures.
                                    disclosed.
  
  
  
  ATTENTION: INTENTIONAL MISSTATEMENTS OR OMISSION OF FACTS CONSTITUTE FEDERAL
  CRIMINAL VIOLATIONS (SEE 18 U.S.C. 1001)
metadata_documents: [{"type": "144", "sequence": "1", "filename": "y50575e144.txt", "description": "FORM 144", "secsgml_size_bytes": 15015}]
text: 1
  FORM 144
                                                     OMB APPROVAL
                                                     ------------
                                     OMB Number                          3235-0101
                                     Expires:                      August 31, 2003
                                     Estimated average burden
                                     hours per response                        2.0
  
                                                                 DOCUMENT SEQUENCE
                                                                 NO.
  
                                                                 -----------------
                                                                 CUSIP NUMBER
  
                                                                 -----------------
                                                                 WORK LOCATION
  
                                                                 -----------------
  
                                   UNITED STATES
                         SECURITIES AND EXCHANGE COMMISSION
                               WASHINGTON, D.C. 20549
                                    SEC USE ONLY
  
                        NOTICE OF PROPOSED SALE OF SECURITIES
               PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933
  
  ATTENTION:  Transmit for filing 3 copies of this form concurrently with either
              placing an order with a broker to execute sale or executing a sale
              directly with a market maker.
  -----------------------------------------------------------------------------------------------------------------------------------
  1(a) NAME OF ISSUER (Please type or print)                                      (b) IRS IDENT. NO.        (c) S.E.C. FILE NO.
  
  i-STAT CORPORATION                                                              22-2542664                000-19841
  -----------------------------------------------------------------------------------------------------------------------------------
                                                                                                          (e) TELEPHONE NO.
  1(d) ADDRESS OF ISSUER          STREET             CITY         STATE          ZIP CODE       AREA CODE                   NUMBER
                                                                                                -----------------------------------
  104 WINDSOR CENTER DRIVE, EAST WINDSOR, NJ 08520                                                 609                     443-9300
  ------------------------------------------------------------------------------------------------------------------------------------
  2(a) NAME OF PERSON FOR WHOSE ACCOUNT   (b) IRS IDENT. NO.    (c) RELATIONSHIP TO   (d) ADDRESS   STREET   CITY   STATE   ZIPCODE
  THE SECURITIES ARE TO BE SOLD                                  ISSUER
  ------------------------------------------------------------------------------------------------------------------------------------
  WILLIAM P. MOFFITT                      ###-##-####            CHIEF EXECUTIVE       412 RAMSEY ROAD, YARDLEY PA 19067
                                                                 OFFICER
  ------------------------------------------------------------------------------------------------------------------------------------
  INSTRUCTION: The person filing this notice should contact the issuer to obtain
           the I.R.S. Identification Number and the S.E.C. File Number.
  ------------------------------------------------------------------------------------------------------------------------------------
  3(a)           (b)                                                                      (c)                 (d)
  TITLE OF THE                                                         SEC USE ONLY        NUMBER OF SHARES        AGGREGATE
    CLASS OF     NAME AND ADDRESS OF EACH BROKER THROUGH WHOM THE                           OR OTHER UNITS          MARKET
   SECURITIES    SECURITIES ARE TO BE OFFERED OR EACH MARKET MAKER     BROKER-DEALER          TO BE SOLD             VALUE
   TO BE SOLD             WHO IS ACQUIRING THE SECURITIES               FILE NUMBER        (See instr. 3(c))   (See instr. 3(d))
  ------------------------------------------------------------------------------------------------------------------------------------
  COMMON         MERRILL LYNCH & CO., INC.                                                  44,444              $726,659.40 AS OF
  STOCK                                                                                                         CLOSE OF BUSINESS
                                                                                                                JUNE 13, 2001
  ------------------------------------------------------------------------------------------------------------------------------------
  ------------------------------------------------------------------------------------------------------------------------------------
  3(a)           (b)                                                   (e)                 (f)                  (g)
  TITLE OF THE                                                          NUMBER OF SHARES       APPROXIMATE         NAME OF EACH
    CLASS OF     NAME AND ADDRESS OF EACH BROKER THROUGH WHOM THE        OR OTHER UNITS       DATE OF SALE          SECURITIES
   SECURITIES    SECURITIES ARE TO BE OFFERED OR EACH MARKET MAKER         OUTSTANDING      (See instr. 3(f))        EXCHANGE
   TO BE SOLD             WHO IS ACQUIRING THE SECURITIES               (See instr. 3(e))    (MO.  DAY  YR.)     (See instr. 3(g))
  ------------------------------------------------------------------------------------------------------------------------------------
  COMMON         MERRILL LYNCH & CO., INC.                             18,531,128          June 18, 2001        NASDAQ
  STOCK                                                                                    THROUGH
                                                                                           NOVEMBER 1,
                                                                                           2001
  ------------------------------------------------------------------------------------------------------------------------------------
  INSTRUCTIONS:
  1. (a) Name of issuer
     (b) Issuer's I.R.S. Identification Number
     (c) Issuer's S.E.C. file number, if any
     (d) Issuer's address, including zip code
     (e) Issuer's telephone number, including area code
  
  2. (a) Name of person for whose account the securities are to be sold
     (b) Such person's I.R.S. identification number, if such person is
         an entity
     (c) Such person's relationship to the issuer (e.g., officer,
         director, 10% stockholder, or member of immediate family of any of the
         foregoing)
     (d) Such person's address, including zip code
  
  3. (a) Title of the class of securities to be sold
     (b) Name and address of each broker through whom the securities are
         intended to be sold
     (c) Number of shares or other units to be sold (if debt securities, give
         the aggregate face amount)
     (d) Aggregate market value of the securities to be sold as of a
         specified date within 10 days prior to the filing of this notice
     (e) Number of shares or other units of the class outstanding, or if
         debt securities the face amount thereof outstanding, as shown by the most
         recent report or statement published by the issuer
     (f) Approximate date on which the securities are to be sold
     (g) Name of each securities exchange, if any, on which the
         securities are intended to be sold
  2
                         TABLE I -- SECURITIES TO BE SOLD
  
     Furnish the following information with respect to the acquisition of the
  securities to be sold and with respect to the payment of all or any part of the
                 purchase price or other consideration therefor:
  ------------------------------------------------------------------------------------------------------------------------------------
                                                            Name of Person from
                                                            Whom Acquired
   Title of     Date you       Nature of                    (If gift, also give        Amount of               Date of    Nature of
   the Class    Acquired       Acquisition Transaction      date donor acquired)       Securities Acquired     Payment    Payment
  ------------------------------------------------------------------------------------------------------------------------------------
  COMMON        SEE            EXERCISE OF STOCK OPTIONS    i-STAT CORPORATION         44,444
  STOCK         "REMARKS"
                SECTION
                BELOW
  ------------------------------------------------------------------------------------------------------------------------------------
  INSTRUCTIONS:
  
  1.  If the securities were purchased and full payment therefor was not made in
      cash at the time of purchase, explain in the table or in a note thereto the
      nature of the consideration given. If the consideration consisted of any
      note or other obligation, or if payment was made in installments describe
      the arrangement and state when the note or other obligation was discharged
      in full or the last installment paid.
  
  2.  If within two years after the acquisition of the securities the person for
      whose account they are to be sold had any short positions, put or other
      option to dispose of securities referred to in paragraph (d)(3) of Rule
      144, furnish full information with respect thereto.
  
  ================================================================================
  
                TABLE II -- SECURITIES SOLD DURING THE PAST 3 MONTHS
  
  Furnish the following information as to all securities of the issuer sold during
  the past 3 months by the person for whose account the securities are to be sold.
  ------------------------------------------------------------------------------------------------------------------------------------
                                                                                                Amount
                                                                                                  of
  Name and Address of Seller               Title of Securities Sold           Date of Sale   Securities Sold         Gross Proceeds
  ------------------------------------------------------------------------------------------------------------------------------------
  WILLIAM P. MOFFITT                       COMMON STOCK                       ALL TRADING     30,556                 $536,856.05
  412 RAMSEY ROAD                                                             DAYS FROM
  YARDLEY PA 19067                                                            3-21-01 TO
                                                                              6-15-01
  ------------------------------------------------------------------------------------------------------------------------------------
  REMARKS:
  
  The shares covered by this Form 144 (the "Shares") are being acquired upon the
  exercise of a stock option granted on December 20, 1991 and are being sold
  pursuant to a Rule 10b5-1 sales plan dated February 26, 2001 (the "Plan"), and
  the representation below regarding the seller's knowledge of material
  information speaks as of that plan adoption date.
  
  The object of the Plan is to generate enough cash to enable the seller to bear
  the costs of exercising additional stock options, beyond those contemplated by
  the Plan, that are expiring within one year.  The seller has no intention at
  this time to sell the shares underlying such additional stock options.
  
  The Plan has been structured to permit an orderly sale over an extended period
  of time, without focusing a sale of all of the Shares within one of the limited
  trading windows available to officers of the issuer.  The sale of the Shares
  should in no way be viewed as a reflection of the opinion of the undersigned
  with respect to the business, condition or prospects of the issuer.
  
  Shares will be sold under the Plan only when the previous day's closing bid
  price per Share (the "Market Price") is at a sufficiently high level to cover
  the exercise price and income taxes associated with the exercise of the options
  which give rise to the Shares.  The Shares will be sold according to the
  following instructions: while the Shares trade at or below a certain Market
  Price, no Shares will be sold; while the Shares trade at a Market Price that is
  within a certain range, only such number of Shares will be sold per trading day
  as equals the greater of (a) 500 shares or (b) the total remaining Shares to be
  sold divided by the number of trading days up to and including November 1, 2001;
  and while the Shares trade at or above a certain Market Price, as many Shares as
  possible will be sold.
  
  INSTRUCTIONS:
  See the definition of "person" in paragraph (a) of Rule 144.  Information is to
  be given not only as to the person for whose account the securities are to be
  sold but also as to all other persons included in that definition.  In addition,
  information shall be given as to sales by all persons whose sales are required
  by paragraph (e) of Rule 144 to be aggregated with sales for the account of the
  person filing this notice.
  
  ATTENTION:
  The person for whose account the securities to which this notice relates are to
  be sold hereby represents by signing this notice that he does not know any
  material adverse information in regard to the current and prospective operations
  of the Issuer of the securities to be sold which has not been publicly
  disclosed.
  
       June 18, 2001                             /s/ WILLIAM P. MOFFITT
  -----------------------                        -----------------------
      DATE OF NOTICE                                   (SIGNATURE)
  
   The notice shall be signed by the person for whose account the securities are
      to be sold.  At least one copy of the notice shall be manually signed.
      Any copies not manually signed shall bear typed or printed signatures.
                                    disclosed.
  
  ATTENTION: INTENTIONAL MISSTATEMENTS OR OMISSION OF FACTS CONSTITUTE FEDERAL
  CRIMINAL VIOLATIONS (SEE 18 U.S.C. 1001)