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                                                                   EXHIBIT 10.15



                        AMENDMENT TO SUPPLY AGREEMENT


     This AMENDMENT TO SUPPLY AGREEMENT is made and entered into as of this 15
day of October, 1998, by and between EKC TECHNOLOGY, INC., a California
corporation ("EKC") and NANOPHASE TECHNOLOGIES CORPORATION, a Delaware
corporation ("Nanophase").


                                      RECITALS


     WHEREAS, EKC and Nanophase entered into a Supply Agreement dated as of
December 31, 1997 (hereinafter the "Supply Agreement"); and


     WHEREAS, the parties hereto desire to amend the Supply Agreement.


     NOW THEREFORE, for and in consideration of the payments to be made
hereunder, and other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties agree as follows:


     1.   Paragraph 5 of the Supply Agreement is hereby amended to read, in its
entirety, as follows:


          "5.  TERMINATION OF EXCLUSIVITY.  If EKC fails to purchase
     from Nanophase an amount of Nanophase Particles required to
     meet the applicable Minimum Quarterly Exclusivity Threshold (set
     forth below), then Nanophase may, upon ninety (90) days prior
     written notice to EKC, terminate the exclusivity obligation of
     Section 2(a); provided, however, EKC shall have the right to cure
     any such deficiency and avoid the termination of Nanophase's
     exclusivity obligation by submitting to Nanophase a prepaid order
     in the amount of such deficiency prior to expiration of the 90-day
     notice period.  In the event the exclusivity obligation of Nanophase
     is so terminated, the remaining rights and obligations of this
     Agreement shall nevertheless remain in full force and effect unless
     terminated in accordance with Section 4 hereof.



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     For each calendar quarter during the term hereof, the Minimum
     Quarterly Exclusivity Threshold shall be as follows:



                                       Minimum Quarterly
                    Calendar Quarter   Exclusivity Threshold
                    -----------------  ---------------------
                                        (000's omitted)
                                          
                    3rd Quarter 1998         50
                    4th Quarter 1998         75
                    1st Quarter 1999         100
                    2nd Quarter 1999         125
                    3rd Quarter 1999         175
                    4th Quarter 1999         250
                    1st Quarter 2000         250
                    2nd Quarter 2000         250
                    3rd Quarter 2000         500
                    4th Quarter 2000         500



For each calendar quarter of each year after the year 2000, the Minimum
Quarterly Exclusivity Threshold shall be an amount equal to the lesser of (i)
two times the total of the Minimum Quarterly Exclusivity Threshold for the
previous year, or (ii) $5,000,000.00, divided in each case by four (4).  For
example, the Minimum Quarterly Exclusivity Threshold for each calendar quarter
of the year 2001 would be $750,000.00, which is determined by adding the
Minimum Quarterly Exclusivity Threshold for each quarter in the year 2000
multiplying that total by two and then dividing by four."

     2.   Paragraph 6 of the Supply Agreement is hereby amended to read, in its
entirety, as follows:

          "6.  TERMINATION OF SUPPLY MAINTENANCE OBLIGATION.  If EKC fails to
     purchase from Nanophase an amount of Nanophase Particles required to meet
     the applicable annual supply maintenance obligation (set forth below),
     Nanophase may terminate its obligation to supply Nanophase Particles
     exclusively to EKC hereunder, except, however, Nanophase shall thereafter
     continue to be obligated to supply EKC with quantities of  Nanophase
     Particles sufficient for EKC to satisfy all orders for CMP Products that
     EKC receives from its customer base existing at the time of such
     termination (the "Supply Maintenance


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     Obligation").  Nanophase may terminate its obligation to supply
     Nanophase Particles other than to EKC's existing customers base upon
     thirty (30) days written notice to EKC following EKC's failure to meet the 
     applicable annual Minimum Supply Maintenance Threshold; however, EKC shall
     have the right to cure such deficiency and avoid such termination by
     submitting to Nanophase a prepaid order for the deficiency in the
     applicable Minimum Supply Maintenance Threshold prior to the expiration of
     the 30-day notice period.  The Minimum Supply Maintenance Threshold shall
     be an amount equal to one-half of the total Minimum Quarterly Exclusivity
     Thresholds for each calendar year. For example, the Minimum Supply 
     Maintenance Threshold for the year 2000 would be $750,000.00, which is 
     determined by adding the Minimum Quarterly Exclusivity Thresholds for each
     calendar quarter of the year 2000 and dividing by two."

     3.   Except as amended hereby, the Supply Agreement shall otherwise remain
in full force and effect.


          IN WITNESS WHEREOF, the parties have caused this Amendment to Supply
Agreement to be executed as of the day and year first above written.


EKC TECHNOLOGY, INC.                                NANOPHASE TECHNOLOGIES
                                                          CORPORATION


By: /s/ Authorized Signatory                        By: /s/ Don Freed
   ---------------------------------                   -------------------------
Title: VP-CMP                                       Title: Vice President
      ------------------------------                      ----------------------



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