Exhibit 3.9
 
     CERTIFICATE OF CORRECTION FILED TO CORRECT A CERTAIN ERROR IN THE AMENDED
     CERTIFICATE TO SET FORTH DESIGNATIONS, VOTING POWERS, PREFERENCES,
     LIMITATIONS, RESTRICTIONS, AND RELATIVE RIGHTS OF SERIES A 6% CUMULATIVE
     CONVERTIBLE PREFERRED STOCK, $0.001 PAR VALUE PER SHARE, AND SERIES B 6%
     CUMULATIVE CONVERTIBLE PREFERRED STOCK, $0.001 PAR VALUE PER SHARE OF
     CHEMTRAK INCORPORATED FILED IN THE OFFICE OF THE SECRETARY OF STATE OF
     DELAWARE ON APRIL 8, 1998

CHEMTRAK INCORPORATED hereby certifies that:

     1.   The name of the corporation is ChemTrak Incorporated, a Delaware
corporation.

     2.   That an AMENDED CERTIFICATE TO SET FORTH DESIGNATIONS, VOTING POWERS,
PREFERENCES, LIMITATIONS, RESTRICTIONS, AND RELATIVE RIGHTS OF SERIES A 6%
CUMULATIVE CONVERTIBLE PREFERRED STOCK, $0.001 PAR VALUE PER SHARE, AND SERIES B
6% CUMULATIVE CONVERTIBLE PREFERRED STOCK, $0.001 PAR VALUE PER SHARE was
filed by the Secretary of State of Delaware on April 8, 1998 and that said
Certificate requires correction as permitted under Section 103 of the General
Corporation Law of the State of Delaware.

     3.   The inaccuracy or defect of said Certificate to be corrected is as
follows: Article III, Section 4(b) included a clerical error.

     4.   Article III, Section 4(b) of the Certificate is corrected to read as
follows:

               (b) Each share of Series B Preferred Stock shall have a stated
     value equal to $1,000 (as adjusted for any stock combinations or splits
     with respect to such shares) (the "Stated Value").  The number of shares of
     Common Stock issuable upon conversion of each share of Series B Preferred
     Stock shall equal (i) the sum of (A) the Stated Value per share and (B)
     accrued and unpaid dividends on such share, divided by (ii) the Conversion
     Price. The Conversion Price shall be equal to the lesser of: (i) one
     hundred percent (100%) of the average of the Closing Bid Price (as
     hereinafter defined) of the Corporation's Common Stock for the five (5)
     trading days immediately preceding the date of issuance of the Series B
     Preferred Stock; or (ii) seventy-five percent (75%) of the average of the
     Closing Bid Price for the five trading days immediately preceding
     conversion of the Series B Preferred Stock.  The Closing Bid Price shall
     mean the closing bid price of the Corporation's Common Stock as reported
     from the NASDAQ SmallCap Market (or if not reported by NASDAQ as reported
     by such other exchange or market where traded).  The Company may elect to
     redeem all of part of the Series B Preferred Stock upon payment of the
     Stated Value (plus any dividends accumulated thereon) multiplied by 1.333
     (the "Redemption Price") to the Holders for each share to be redeemed.  The
     date notice of redemption is given to the Holder is the 

 
     Redemption Date. The Company shall effect a Redemption by written notice to
     the Holder. The Redemption Price must be paid by the Company to the Holder
     not sooner than five business days, but not later than ten business days
     after such notice is sent. The Company may not redeem any amount that the
     Holder has elected to convert, including a notice of conversion given after
     the Redemption Date but prior to receipt by the Holder of the Redemption
     Price. In the event the Company gives written notice to affect a
     redemption, but fails to timely pay the Redemption Price, then the Holder
     may elect to avoid the Redemption Notice. After such failure, the Company
     will no longer have the right to affect any Redemption.

     IN WITNESS WHEREOF, said CHEMTRAK INCORPORATED has caused this Certificate
to be signed by Edward Covell, its President, and attested by Donald Fluken, its
Chief Financial Officer, this 21st day of May, 1998.

     Signed on this 21st day of May, 1998.

                              CHEMTRAK, INCORPORATED



                              By: /s/ Edward Covell
                                 _________________________________
                                 Edward Covell, President


ATTEST:

/s/ Donald Fluken
________________________________
Donald Fluken, Chief Financial Officer


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