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                                                                   EXHIBIT 10.48

                      FIRST AMENDMENT TO SECURITY AGREEMENT


         THIS FIRST AMENDMENT TO SECURITY AGREEMENT (this "Amendment"),
effective as of the 28th day of February, 2001, is by and between COLORADO
MEDTECH, INC. ("Medtech"), CIVCO MEDICAL INSTRUMENTS CO. INC. ("Civco"), BIOMED
Y2K, INC. ("Biomed"), CMED CATHETER AND DISPOSABLES TECHNOLOGY, INC. "CMed")
(Medtech, Civco, Biomed and CMed shall be collectively referred to herein as
"Debtor"), and KEYBANK NATIONAL ASSOCIATION, a national banking association
("Secured Party").

                                    RECITALS:

         A. On December 21, 2000, Debtor, as Borrower, and Secured Party, as
Lender, entered into that certain Credit Agreement (the "Credit Agreement")
pursuant to which Lender agreed to extend credit to Debtor, in an aggregate
amended principal amount at any time outstanding not in excess of $15,000,000
(the "Loan"), and secured by, among other items, a Security Agreement dated as
of December 21, 2000 (the "Security Agreement") executed by Debtor and Secured
party.

         B. Debtor and Secured Party desire to further amend the Security
Agreement under the terms and conditions set forth herein.

                                   AGREEMENT:

         NOW, THEREFORE, in consideration of the foregoing premises and other
good and valuable consideration, the receipt, adequacy and sufficiency of which
are hereby acknowledged, the parties hereto covenant and agree as follows:

         1. SECURITY AGREEMENT AMENDMENTS. The Security Agreement is hereby
amended as follows:

                  (a) Paragraph 4(b) of the Security Agreement shall be deleted
         in its entirety and replaced with the following:

                           "(b) All deposit accounts, reserves, deferred
                  payments, refunds, accounts receivable, notes, and chattel
                  paper; all books, records and other documentation relating to
                  the foregoing including, without limitation, all listing and
                  compilations of such accounts and all original documents
                  creating, evidencing, securing or guaranteeing the
                  indebtedness under any such accounts such as contracts,
                  orders, invoices, receipts, security documents and
                  guarantees;".

         2. DOCUMENT RATIFICATION. Subject to the amendment set forth in
Paragraph 1 above, all of the terms and conditions contained in the Security
Agreement, shall remain unmodified and in full force and effect.


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         3. RELEASE. Except as specifically set forth herein, the execution of
this Amendment by Secured Party does not and shall not constitute a waiver of
any rights or remedies to which Secured Party is entitled, nor shall the same
constitute a waiver of any default now existing or which may occur in the future
with respect to the Loan Documents.

         4. REPRESENTATIONS OF BORROWER. Debtor hereby confirms that, as of the
date hereof, (i) Debtor is in compliance with each of the representations,
warranties and covenants of Borrower set forth in the Security Agreement, (ii)
no Event of Default exists under the Security Agreement and (iii) no fact or
condition exists, which with the passage of time and/or giving of notice, would
constitute an Event of Default under the Security Agreement.

         5. CONTROLLING LAW. The terms and provisions of this Amendment shall be
construed in accordance with and governed by the laws of the State of Colorado.

         6. BINDING EFFECT. This Amendment shall be binding upon and inure to
the benefit of the parties hereto, their successors and assigns.

         7. CAPTIONS. The paragraph captions utilized herein are in no way
intended to interpret or limit the terms and conditions hereof, rather, they are
intended for purposes of convenience only.

         8. COUNTERPARTS. This Amendment may be executed in any number of
counterparts, each of which shall be effective only upon delivery and thereafter
shall be deemed an original, and all of which shall be taken to be one and the
same instrument, for the same effect as if all parties hereto had signed the
same signature page. Any signature page of this Amendment may be detached from
any counterpart of this Amendment without impairing the legal effect of any
signatures thereon and may be attached to another counterpart of this Amendment
identical in form hereto but having attached to it one or more additional
signature pages.

         9. DEFINED TERMS. Capitalized terms not defined herein shall have the
same meaning as set forth in the Credit Agreement and/or the Security Agreement.

         IN WITNESS WHEREOF, the parties hereto have executed this Amendment as
of the day and year first above written.


                                       COLORADO MEDTECH, INC., a Colorado
                                       corporation

                                       By: /s/ Gregory A. Gould
                                           --------------------
                                       Name: Gregory A. Gould
                                       Title: Chief Financial Officer


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                                       CIVCO MEDICAL INSTRUMENTS CO., INC., an
                                       Iowa corporation

                                       By: /s/ Charles R. Klasson, Jr.
                                           ---------------------------
                                       Name: Charles R. Klasson, Jr.
                                       Title: President


                                       BIOMED Y2K, INC., a Colorado corporation

                                       By: /s/ Stephen K. Onody
                                           --------------------
                                       Name: Stephen K. Onody
                                       Title: President


                                       CMED CATHETER AND DISPOSABLES
                                       TECHNOLOGY, INC., a Minnesota corporation

                                       By: /s/ Stephen K. Onody
                                           --------------------
                                       Name: Stephen K. Onody
                                       Title: President

                                       LENDER:

                                       KEYBANK NATIONAL ASSOCIATION

                                       By: /s/ Michelle K. Bushey
                                           ----------------------
                                       Name: Michelle K. Bushey
                                       Its: Vice President

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                       FIRST AMENDMENT TO CREDIT AGREEMENT



         THIS FIRST AMENDMENT TO CREDIT AGREEMENT (this "First Amendment"),
effective as of the 30th day of April, 2001, is by and among COLORADO MEDTECH,
INC. ("Medtech"), CIVCO MEDICAL INSTRUMENTS CO. INC. ("Civco"), BIOMED Y2K, INC.
("Biomed"), CMED CATHETER AND DISPOSABLES TECHNOLOGY, INC. "CMed") (Medtech,
Civco, Biomed and CMed shall be collectively referred to herein as "Borrower"),
and KEYBANK NATIONAL ASSOCIATION, a national banking association (the "Lender
").

                                    RECITALS:

         A. On December 21, 2000, Borrower and Lender entered into that certain
Credit Agreement (the "Credit Agreement") pursuant to which Lender agreed to
extend credit to Borrower, on a revolving basis, in an aggregate principal
amount at any time outstanding not in excess of $15,000,000 (the "Loan"), as
evidenced by that certain Promissory Note dated December 21, 2000 (the "Note"),
and secured by, among other items, a Security Agreement dated December 21, 2000,
as amended by First Amendment to Security Agreement dated February 28, 2001 (the
"Security Agreement") executed by Borrower and Lender.

         B. Upon the terms and conditions set forth herein, Lender and Borrower
desire to amend the Credit Agreement by documenting Lender's approval of the
sale of CMed, removing CMed as a Borrower thereunder, releasing CMed from the
Note and Security Agreement, and filing a UCC-3 to release the CMed assets from
the UCC-1 Financing Statement filed by the Lender.

         C. All references herein to the Loan Documents shall refer collectively
to the Credit Agreement, Note, Security Agreement, and any other instruments or
documents evidencing, securing or relating to the Loan, as amended by this First
Amendment.

                                   AGREEMENT:

         NOW, THEREFORE, in consideration of the foregoing premises and other
good and valuable consideration, the receipt, adequacy and sufficiency of which
are hereby acknowledged, the parties hereto covenant and agree as follows:

         1. LENDER'S APPROVAL OF SALE OF Cmed (a wholly owned Subsidiary of
Medtech). Pursuant to Section 6.5 of the Credit Agreement, Lender hereby
consents to the sale of CMed by Medtech.

         2. MODIFICATION OF DEFINITION OF "BORROWER". The term "Borrower" as
used in the Loan Documents is hereby modified to delete all references to CMed,
and accordingly is hereby amended to collectively refer to, on a joint and
several basis, Medtech, Civco and Biomed.

         3. RELEASE FROM NOTE. Lender hereby releases CMed from any and all
obligations as a Borrower under the Note.



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         4. RELEASE FROM SECURITY AGREEMENT. Lender hereby releases CMed from
any and all obligations as a Debtor under the Security Agreement, and agrees to
execute a UCC-3 terminating that certain UCC-1 Financing Statement filed by
Lender with the Minnesota Secretary of State on March 9, 2001.

         5. LOAN DOCUMENT AMENDMENTS. Each of the Loan Documents is hereby
amended to conform to the amendments to the Credit Agreement set forth in
Paragraphs 1, 2, 3 and 4 above.

         6. DOCUMENT RATIFICATION. Subject to the amendments set forth in
Paragraphs 1, 2, 3 and 4 above, all of the terms and conditions contained in the
Credit Agreement and the other Loan Documents, shall remain unmodified and in
full force and effect.

         7. RELEASE. Except as specifically set forth herein, the execution of
this First Amendment by Lender does not and shall not constitute a waiver of any
rights or remedies to which Lender is entitled pursuant to the Loan Documents,
nor shall the same constitute a waiver of any default now existing or which may
occur in the future with respect to the Loan Documents. Borrower hereby agrees
that Lender has fully performed its obligations pursuant to the Loan Documents
through the date hereof.

         8. REPRESENTATIONS, WARRANTIES AND COVENANTS OF BORROWER. Borrower
represents, warrants and covenants to Lender:

                  (a) No default or event of default under any of the Loan
         Documents as modified herein, nor any event, that, with the giving of
         notice or the passage of time or both, would be a default or an event
         of default under the Loan Documents as modified herein has occurred and
         is continuing.

                  (b) There has been no material adverse change in the financial
         condition of Borrower or any other person whose financial statement has
         been delivered to Lender in connection with the Loan from the most
         recent financial statement received by Lender.

                  (c) Each and all representations and warranties of Borrower in
         the Loan Documents, are accurate on the date hereof.

                  (d) Borrower has no claims, counterclaims, defense, or
         set-offs with respect to the Loan or the Loan Documents as modified
         herein.

                  (e) The Loan Documents as modified herein are the legal,
         valid, and binding obligation of Borrower, enforceable against Borrower
         in accordance with their terms.

                  (f) Borrower shall execute, deliver, and provide to Lender
         such additional agreements, documents, and instruments as reasonably
         required by Lender to effectuate the intent of this First Amendment.


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         9. CONTROLLING LAW. The terms and provisions of this First Amendment
shall be construed in accordance with and governed by the laws of the State of
Colorado.

         10. BINDING EFFECT. This First Amendment shall be binding upon and
inure to the benefit of the parties hereto, their successors and assigns.

         11. CAPTIONS. The paragraph captions utilized herein are in no way
intended to interpret or limit the terms and conditions hereof, rather, they are
intended for purposes of convenience only.

         12. COUNTERPARTS. This First Amendment may be executed in any number of
counterparts, each of which shall be effective only upon delivery and thereafter
shall be deemed an original, and all of which shall be taken to be one and the
same instrument, for the same effect as if all parties hereto had signed the
same signature page. Any signature page of this First Amendment may be detached
from any counterpart of this First Amendment without impairing the legal effect
of any signatures thereon and may be attached to another counterpart of this
First Amendment identical in form hereto but having attached to it one or more
additional signature pages.

         13. DEFINED TERMS. Capitalized terms not defined herein shall have the
same meaning as set forth in the Credit Agreement.

         IN WITNESS WHEREOF, the parties hereto have executed this First
Amendment as of the day and year first above written.

                                       BORROWER:

                                       COLORADO MEDTECH, INC., a Colorado
                                       corporation

                                       By:   /s/ Stephen K. Onody
                                             --------------------
                                       Name: Stephen K. Onody
                                       Its:  President

                                       CIVCO MEDICAL INSTRUMENTS CO., INC., an
                                       Iowa corporation

                                       By:   /s/ Stephen K. Onody
                                             --------------------
                                       Name: Stephen K. Onody
                                       Its:  Vice President

                                       BIOMED Y2K, INC., a Colorado corporation

                                       By:   /s/ Stephen K. Onody
                                             --------------------
                                       Name: Stephen K. Onody
                                       Its:  President


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                                       CMED CATHETER AND DISPOSABLES
                                       TECHNOLOGY, INC., a Minnesota corporation

                                       By:   /s/ Stephen K. Onody
                                             --------------------
                                       Name: Stephen K. Onody
                                       Its:  President


                                       LENDER:

                                       KEYBANK NATIONAL ASSOCIATION, a
                                       national banking association

                                       By:   /s/ Michelle K. Bushey
                                             ----------------------
                                       Name: Michelle K. Bushey
                                       Its:  Vice President