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                                                               EXHIBIT NO. 10.55



                        INDEPENDENT CONSULTANT AGREEMENT

        THIS INDEPENDENT CONSULTANT AGREEMENT ("Agreement") is entered into
effective as of October 1, 1999 by and between AMDL, Inc., a Delaware
corporation, ("AMDL"), and That T. Ngo, Ph.D., an individual, ("Consultant").

        AMDL wishes to engage the services of Consultant in accordance with the
terms and conditions of this Agreement, and in consideration of the covenants
and agreements set forth below, the parties agree as follows.

        1. Engagement; Consultant Services. Consultant is requested to provide
continuing consulting services to review and analyze new technologies and
supervise continued testing of existing products and such other services related
to diagnostic technology as the Board of Directors may request. AMDL hereby
engages consultant to provide the services described in this Agreement and
Consultant hereby accepts the engagement, upon the terms and conditions set
forth in this Agreement. Consultant shall provide these consulting services at
the time and place as AMDL may reasonable request, ("Services"). Consultant
shall devote such reasonable time, effort and attention to the performance of
the "Services" as may be required subject to Consultant's availability.
Consultant agrees to make an average of at least eight hours per week available.

        2. Term. The engagement of Consultant shall commence on the date of this
Agreement and shall terminate on September 30, 2000 unless terminated earlier in
accordance with this Agreement.

        3. Best Efforts. Consultant will use his best efforts in the performance
of the obligations and duties arising out of this agreement.

        4. Independent Contractor.

           (a) Consultant and AMDL acknowledge and agree (i) that nothing in
this Agreement shall be considered to create an employer-employee relationship
between AMDL and Consultant; and (ii) that Consultant shall not be deemed to be
an employee of AMDL for any purpose whatsoever, including, but not limited to,
eligibility for (1) inclusion in any retirement benefit plan for the employees
of AMDL, (2) sick pay, (3) paid non-working holidays, (4) paid vacation or leave
days, (5) participation in any plan or program offering life, accident or health
insurance for the employees of AMDL or (6) participation in any medical
reimbursement plan of other fringe benefit plan for the employees of AMDL except
as provided herein.

           (b) Consultant is not authorized to waive any right or to enter into,
incur, assume or create any debt, obligation, contract or release of any kind in
the name or on behalf of AMDL.

           (c) Consultant is solely responsible for the payment of any and all
self-employment taxes and assessments resulting from the payment of compensation
to, or the performance of Services by Consultant pursuant to this Agreement
including, without limitation, any California unemployment insurance tax,
federal, state and foreign income taxes, federal Social Security (FICA) payments
and California disability insurance taxes.

        5. Fees, Expenses and Other Compensation. AMDL specifically agrees that
Consultant shall receive a consulting fee for each calendar month, commencing
with the month of October 1999, ("Calendar Month") of the agreement equal to the
greater of $4,800 or $150 per hour times the number of hours, rounded to the
next hour, with a target of 40 hours per month ("Consulting Fee").

        6. Food, Lodging and Travel Expenses. AMDL shall reimburse for
reasonable and necessary expenses incurred by Consultant for food,
transportation, and lodging in connection with the performance of the Services
for AMDL provided that such expenses are properly documented and submitted to
AMDL.



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        7. Other Expenses. AMDL shall reimburse for such other expenses,
including capital expenses, supplies, telephone, mail, copying services,
equipment and other tangible personal property to be purchased by Consultant
("Other Costs"), provided that such Other Costs are approved in advance of
purchase by AMDL. Such approval may take the form of a written notice of
approval, or telephonic approval followed by written confirmation. The amount to
be reimbursed for such Other Costs shall not exceed the amount approved in
advance by AMDL.

        8. Payment. Payment of the Consulting Fee, food, lodging and travel
expenses shall be received by Consultant on or before seven calendar days
subsequent to receipt by AMDL of an invoice of same from Consultant.

        9. Confidential Information. Consultant agrees and acknowledges that
rendering Services under this Agreement Consultant will have access to certain
information and data of AMDL, (including, without limitation, business plans,
financial statements and other financial information, projections and budget
information, internal memoranda, customer lists, technology, marketing and sales
information, methods of conducting business, legal matters, confidential
communications and information developed by Consultant under this agreement for
AMDL) and that such information and data constitutes valuable special and unique
property of AMDL (the foregoing collectively referred to as "Confidential
Information"). Accordingly, Consultant agrees that during the term of this
agreement and for one year after termination hereof, Consultant shall not
impart, disclose or reveal to any other person or entity any Confidential
Information in any manner, or for any purpose, without the prior written consent
of AMDL. Consultant agrees that all items of Confidential Information are
proprietary to AMDL and shall remain the sole property of AMDL notwithstanding
that Consultant may have participated or will participate in the development of
Confidential Information.

        10. Return of Confidential and Proprietary Information. Upon expiration
or termination or this Agreement, Consultant shall immediately return to AMDL
all copies of Confidential Information obtained in connection with the
performance of Services and developed in connection with the performance of
Services.

        11. Intellectual Property Rights. All inventions or improvements,
trademark / service mark concepts, designs, or the like, or published materials
premised upon information received or work done by Consultant pursuant to this
Agreement or within one year after the termination of this agreement, whether
patentable, registrable, copyrightable or not, shall be solely for the benefit
of AMDL as "works made for hire" as appropriate. Consultant shall assign all
right, title and interest in any inventions or improvements to AMDL or its
nominee, and shall assist AMDL or its nominee in obtaining and maintaining
whatever protection thereon AMDL or its nominee may deem appropriate, both in
the United States and abroad. Any patent applications filed by AMDL inventions
attributable to work performed under this Agreement will list the names of all
inventors who contributed to the claims of the patent application in accordance
with the requirement of Title 35 of the United States Code.

        12. Termination of Agreement. Consultant may terminate this Agreement
for any reason with or without cause, upon ninety days written notice of
termination to AMDL. AMDL may terminate this Agreement for any reason with or
without cause, upon ninety days written notice of termination to Consultant.

        13. Limited Liability. Consultant will not be liable to AMDL, or to
anyone who may claim any right due to a relationship with AMDL, for any acts or
omissions ("Acts") in the performance of Service under the terms of this
Agreement or on the part of the employees or agents of Consultant unless those
Acts or omissions are due to willful misconduct. AMDL will indemnify and hold
Consultant free and harmless from any obligations, costs, claims, judgments,
attorneys' fees and attachments arising from, growing out of, or in any way
connected with the services rendered to AMDL under the terms of this Agreement,
unless Consultant's Acts are adjudicated to be the result of willful misconduct

        14. Notices. All notices, requests or other communications (collectively
"Notices") which are given with respect to this Agreement must be in writing and
must be either personally delivered or mailed by first class mail, to the
recipient at the address indicated below:



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               To Consultant:       That T. Ngo, Ph.D.
                                    15 Deer Creek
                                    Irvine, CA 92604-3070

               To AMDL:             2492 Walnut Ave Suite 100
                                    Tustin, CA 92780

Or such other address or to the attention of such other person as the recipient
party shall have specified by prior written notice to the sending party. Any
notice under this agreement will be deemed to have been given when so delivered
or mailed.

        15. Governing Law. This Agreement shall be governed by, construed and
enforced in accordance with, the internal laws of the State of California
applicable to agreements made and to be performed wholly within the State of
California. The sole forum for resolving disputes arising under or relating to
this Agreement shall be the Municipal and Superior Courts for the County of
Orange, California, or the Federal District Court for the Central District of
California and all related appellate courts, and the parties hereby consent to
the jurisdiction of such courts and agree that venue shall be in Orange County,
California.

        16. Modifications, Amendments, Waivers and Extensions. This Agreement
may not be modified, changed or supplemented, nor may any obligations hereunder
be waived or extensions of time for performance granted, except by written
instrument signed by both parties to this Agreement or as otherwise expressly
permitted herein. No waiver of any breach of any agreement or provision of this
Agreement shall be deemed a waiver of any preceding or succeeding breach thereof
or of any other agreement or provision contained in this Agreement. No extension
of time for performance of any obligations or acts shall be deemed an extension
of the time for performance of any other obligations or acts.

        17. Attorneys' Fees. In the event any action in law or equity is brought
for the enforcement of this Agreement or in connection with any of the
provisions of this Agreement, the prevailing party shall be entitled to receive
from the other party all costs and expenses, including reasonable attorneys'
fees, reasonable incurred in connection with such action.

        18. Assignment. This Agreement may not be assigned or delegated by
either party without the prior written consent of the other party.

        19. Partial Invalidity. Any provision of this Agreement which is found
to be invalid or unenforceable by any court in any jurisdiction shall, as to
that jurisdiction, be ineffective to the extent of such invalidity or
unenforceability, and the invalidity or unenforceability of such provision shall
not affect the validity or enforceability of the remaining provisions of this
Agreement.

        20. Miscellaneous: This Agreement.

            (a) Constitutes the entire agreement and supersedes all prior
written or oral, and all contemporaneous oral agreements, understandings and
negotiations between the parties with respect to the subject matter of this
Agreement;

            (b) May be executed in counterparts, each of which shall be deemed
an original and all of which shall constitute one and the same instrument;



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            (c) Is not intended to confer upon any person other than the parties
to this Agreement any rights or remedies under this Agreement.

        The parties have executed this Agreement as of the day and year first
above written.




Consultant                                  AMDL, Inc.
An Individual                               a Delaware Corporation



By: _______________________________         By: ______________________________
        That T. Ngo, Ph.D.                         Gary L. Dreher

        Title:  Consultant                         Title:  President



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