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                                                                   EXHIBIT 10.13


                        CLINICAL RESEARCH STUDY AGREEMENT


This Agreement is entered into as of the 22 day of July, 1993, by and between
Emory University, located at 1462 Clifton Road, NE, Room 302, Atlanta, GA 30322
(hereinafter referred to as "UNIVERSITY"), and SpectRx, Inc., a Delaware
corporation, located at 6040C Unity Drive, Norcross, GA 30071 (hereinafter
referred to as "COMPANY").

                                   BACKGROUND

The COMPANY has ongoing research in the area of using the fluorescence of lens
proteins and other tissues for the non-invasive diagnosis of disease. This
research has led to the issuance of U.S. Patent No. 5,203,328. The COMPANY has
one other patent application on file with two others in preparation for filing.

The COMPANY wishes to obtain from the UNIVERSITY an option to obtain certain
rights to inventions or discoveries that are developed solely by the UNIVERSITY
during the course of research funded by the COMPANY hereunder.

The COMPANY wishes to verify its hypothesis that certain fluorescence signals
are related to the glycosolation of lens proteins, advanced glycosolation end
products, screening for diabetes and measurement of Glycosolated Hemogolobins.
The COMPANY believes the UNIVERSITY to be capable of contributing to the
verification this hypotheses by the application of these techniques to human
patients according to the clinical study protocol provided by the COMPANY.

                                WITNESSETH THAT:

The UNIVERSITY agrees to conduct a clinical research study entitled "Clinical
Evaluation of a Non-Invasive Lens Measurement System for Detecting and
Monitoring Diabetes Mellitus" according to the protocol attached as Exhibit A.
In this undertaking, the UNIVERSITY agrees to devote its best efforts in order
to perform efficiently the work required under this Agreement. The UNIVERSITY
agrees that it will comply with all applicable laws, rules and regulations
relating to the conduct of such study, particularly such laws, rules and
regulations concerning or promulgated by the Food and Drug Administration. The
COMPANY will provide a prototype Lens Measurement System for the use in the
study. The SpectRx Lens Measurement System is not yet approved by the U.S. Food
and Drug Administration. To the extent any portions of Exhibit A are
inconsistent with this Agreement, the terms of this Agreement shall govern.

1.       Principal Investigator

         The study performed under this Agreement will be under the direction of
         Dr. Dan Gallina (hereinafter "INVESTIGATOR").


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2.       Human Subjects

         This protocol has been approved by the UNIVERSITY's Institutional
         Review Board (Exhibit B) and the COMPANY. The UNIVERSITY shall obtain
         from each of the patients participating in this study, advanced
         informed consent in compliance with 21 CFR 50.20 through 50.27 and any
         modifications thereof as may be adopted. COMPANY will reimburse
         UNIVERSITY and/or the patient for the reasonable costs and expenses
         incurred in diagnosing and treating unanticipated adverse effects,
         injuries, illnesses, or reactions that result from the use or
         application of COMPANY's investigational drug or device in the course
         of this study.

3.       Indemnification

         The "Indemnification Agreement for Clinical Study" is attached as
         Exhibit C and is incorporated by reference.

4.       UNIVERSITY and COMPANY Contacts

         The UNIVERSITY's scientific contact for this Agreement will be Dr. Dan
         Gallina at (404) 242-8723. The UNIVERSITY's administrative contact for
         this Agreement will be Ms. Nancy Wilkerson at (404) 727-2503. The
         COMPANY's scientific contact will be Mr. Jonathan Eppstein at (404)
         242-8723. The COMPANY's administrative contact for the Agreement will
         be Mr. Mark A. Samuels at (404) 242-8723.

5.       Period of Performance

         The term of this Agreement shall be from the date of this Agreement is
         accepted until the study is either completed or terminated. It is
         anticipated that the study will begin on July 19, 1993 and be completed
         by March 1994.

6.       Payment Schedule

         A.       Payments shall be made payable to EMORY UNIVERSITY and
                  forwarded to the following address:

                        Mr. William J. Mulcahy
                        Assistant Vice President for Finance
                        Office of Grants and Contracts Accounting
                        313 Administration Building
                        1380 South Oxford Road
                        Atlanta, GA 30322
                        (404) 727-4240

                  It is agreed that the COMPANY will reimburse the UNIVERSITY
                  for an amount not to exceed $99,960.00 in accordance with the
                  approved budget and payment schedule 



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                  attached as Exhibit D. COMPANY acknowledges that the
                  UNIVERSITY has included its indirect costs for this clinical
                  study. For purposes of identification, payments will include
                  the title of the project and the name of the INVESTIGATOR.

         B.       In the event of termination, the sum for professional services
                  and expenses payable under this Agreement shall be limited to
                  the pro-rated fees based on actual work performed and actual
                  expenses committed pursuant to the protocol. Any unexpended
                  funds not due under this calculation but already paid shall be
                  returned to the COMPANY.

7.       Independent Contractor

         Each party to this Agreement shall act as an independent contractor and
         shall not be construed for any purpose as the agent, employee, servant
         or representative of the other party, and neither party shall enter
         into any contract or agreement with a third party which purports to
         obligate or bind the other party.

8.       Publications

         The UNIVERSITY shall have publication privileges in reference to the
         subject study. In this regard, UNIVERSITY shall furnish COMPANY with a
         copy of any proposed publication at least thirty (30) days in advance
         of the proposed submission date. Within this thirty day period, COMPANY
         shall review said proposed publication for technical content, including
         patentable inventions, and for the disclosure of any proprietary
         information which COMPANY may have furnished to facilitate the subject
         study under this Agreement, and COMPANY shall inform UNIVERSITY in
         writing of the location and content of specific proprietary information
         contained in the proposed publication. Upon receiving the appropriate
         written notification from COMPANY, UNIVERSITY shall edit the proposed
         publication to remove COMPANY's proprietary information before
         submission, and further, shall delete disclosure of potentially
         patentable inventions, or delay submission for ninety (90) days until
         the appropriate patent application can be filed. In the event COMPANY
         does not respond to the submission within such time, approval will be
         deemed to have been given.

         The COMPANY shall also have publication privileges in reference to the
         subject study. In this regard, COMPANY shall furnish UNIVERSITY with a
         copy of any proposed publication at least thirty (30) days in advance
         of the proposed submission date. Within this thirty day period,
         UNIVERSITY shall review said proposed publication for technical
         content, including patentable inventions, and for the disclosure of any
         proprietary information which UNIVERSITY may have furnished to
         facilitate the subject study under this Agreement. UNIVERSITY shall
         inform COMPANY in writing of the location and content of specific
         proprietary information contained in the proposed publication. Upon
         receiving the appropriate written notification from UNIVERSITY, COMPANY
         shall edit the proposed publication to remove UNIVERSITY's proprietary
         information before submission, and further, shall delete disclosure of
         potentially patentable inventions, or delay submission for ninety (90)
         days until the appropriate patent 



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         application can be filed. In the event UNIVERSITY does not respond to
         the submission within such time, approval will be deemed to have been
         given.

9.       Confidentiality

         Subject to the provisions of Paragraph 8, the INVESTIGATOR agrees to
         hold all information disclosed to it under this Agreement that the
         COMPANY has advised the UNIVERSITY in writing is confidential for a
         period of five (5) years from the date of termination of this Agreement
         except,

         A.       Information that is now in the public domain or subsequently
                  enters the public domain through no fault of INVESTIGATOR or
                  UNIVERSITY;

         B.       Information that is presently known or becomes known to
                  INVESTIGATOR or UNIVERSITY from its own independent sources;

         C.       Information that INVESTIGATOR or UNIVERSITY receives from any
                  third party not under any confidential obligation to keep such
                  information confidential;

         D.       Information that is required to be disclosed by law.

10.      Inventions and Patents Rights

         A.       It is expressly agreed that neither the COMPANY nor the
                  UNIVERSITY transfers by operation of this Agreement to the
                  other party any rights to any Invention, Discovery, or other
                  proprietary rights either party owns as of the commencement
                  date of this Agreement, except as specifically set forth
                  herein.

         B.       Ownership of Inventions and Discoveries: Any Invention or
                  Discovery made by COMPANY as a result of the clinical study
                  activities pertaining to this Agreement herein, if discovered
                  or developed solely by COMPANY personnel or based on the
                  results of the clinical study shall, from the time of
                  conception, be the property of the COMPANY. Any Invention or
                  Discovery made by UNIVERSITY during the clinical study
                  activities pertaining to this Agreement herein, if solely by
                  UNIVERSITY personnel and not based on the results of the
                  Clinical Study shall, from the time of conception, be the
                  property of the UNIVERSITY. Any Invention or Discovery made
                  jointly by both COMPANY and UNIVERSITY during the clinical
                  study activities pertaining to this Agreement herein and not
                  based on the results of the Clinical Study, if jointly
                  discovered or developed with associates from COMPANY and
                  UNIVERSITY personnel shall, from the time of conception, be
                  the joint property of both COMPANY and UNIVERSITY.

         C.       Jointly Owned Inventions or Discoveries: In the case of
                  jointly owned Inventions or Discoveries, COMPANY and
                  UNIVERSITY shall negotiate a sharing agreement suitable for
                  the management of such Invention or Discovery. Such sharing
                  agreement shall 



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                  include, but not be limited to, revenue and expense sharing,
                  the party responsible for patent prosecution, the party
                  responsible for marketing, and the party responsible for
                  license negotiation.

         D.       Option and License Provisions: To the extent permitted by
                  existing UNIVERSITY policies and regulations, COMPANY shall be
                  given a ninety (90) day option to obtain a royalty- bearing,
                  world-wide, exclusive license to any patentable Invention or
                  Discovery made by the UNIVERSITY during the clinical study
                  activities pertaining to this Agreement and for which COMPANY
                  agrees to reimburse or pay the expenses of the patent
                  application. Such license agreement shall contain reasonable
                  terms based on industry standards in agreements relating to
                  similar products and technology, and any other relevant facts.
                  If at the expiration of such ninety (90) day period the
                  COMPANY has failed to exercise its option and execute a
                  license agreement, UNIVERSITY shall be free to offer an option
                  with respect to such Invention or Discovery to other third
                  parties.

         The option for a license granted herein, and any resulting license
         shall be subject to any agreement the UNIVERSITY may have or hereafter
         enter with the Government, and to obligations to third parties existing
         prior to the date of this Agreement. The UNIVERSITY warrants that it
         has identified any such prior agreements in writing to the COMPANY
         prior to entering into this agreement.

         Notwithstanding any provision to the contrary in the Agreement, the
         UNIVERSITY shall retain the right to practice any Invention or
         Discovery developed hereunder for its own use.

11.      Data Ownership

         Any medical records generated under this Agreement shall be the
         property of UNIVERSITY. COMPANY shall retain ownership of all completed
         case medical record forms supplied by COMPANY and UNIVERSITY shall be
         entitled to retain copies of the case medical record forms. UNIVERSITY
         shall, within the bounds of legal requirements, make such medical
         records available for review and copying by COMPANY.

         UNIVERSITY shall be entitled to retain ownership of the data arising
         out of this clinical study. Subject to paragraphs 8 and 10, COMPANY
         shall have access to the data and may freely use such data in
         connection with any of its research, development, marketing or
         promotional activities and may be disclosed by the COMPANY to other
         clinical investigators, consultants, the Food and Drug Administration
         and other Federal, State and/or local regulatory agencies.

12.      Publicity

         COMPANY will not include the UNIVERSITY in any advertising, sales
         promotion or other publicity matter without the prior written approval
         of the UNIVERSITY. Likewise, the UNIVERSITY will not include the
         COMPANY in any advertising, sales promotion or other publicity matter
         without the prior written approval of the COMPANY.



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13.      Termination

         The study may be terminated prior to completion by written notice from
         the COMPANY to the UNIVERSITY or by the UNIVERSITY to the COMPANY for
         any of the following reasons:

         A.       Notification to the COMPANY from Federal or State Regulatory
                  Authorities to terminate said study;

         B.       Determination by the COMPANY or the UNIVERSITY that the
                  UNIVERSITY, after a reasonable opportunity, is unable for any
                  reason to perform the study satisfactorily as required in the
                  protocol;

         C.       Inability of the INVESTIGATOR to continue the study at the
                  UNIVERSITY and a successor acceptable to both UNIVERSITY and
                  COMPANY is not available.

         Written notice of its decision to exercise such termination right shall
         be given to the UNIVERSITY by the COMPANY or to the COMPANY by the
         UNIVERSITY by Certified Mail, delivered fifteen (15) days before said
         termination of the study.

         Immediately upon receipt of a notice of termination by either the
         COMPANY or the UNIVERSITY, the UNIVERSITY shall stop entering patients
         into the study and shall cease conducting procedures, to the extent
         medically permissible, on patients already entered into the
         investigational protocol. In the event of termination, expenses payable
         to the UNIVERSITY shall be stated in paragraph (6B).

         Termination or completion of this Agreement, however, shall not relieve
         the obligations undertaken by the parties in paragraphs 3, 8, 10, 12
         and 13.

14.      Modifications

         Any alteration in or amendment to this Agreement must be approved in
         writing by the UNIVERSITY and the COMPANY prior to such alteration or
         amendment becoming effective.

         Any modifications to the attached protocol must be agreed upon by
         INVESTIGATOR and COMPANY and approved by UNIVERSITY's Institutional
         Review Board.

15.      Governing Law

         This Agreement shall be governed by and construed in accordance with
         the laws of the State of Georgia.



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16.      Order of Precedence

         The terms this Agreement shall take precedence over other documentation
         in the interpretation and resolution of disputes concerning this study.

IN WITNESS WHEREOF, the parties have executed this Agreement on the day and year
first above written.


/s/ Mark A. Samuels                /s/ Ann R. Stevens
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SpectRx, Inc.                      Emory University


By:  Mark A. Samuels               By: Ann R. Stevens, Ph.D.
- -------------------------------       ------------------------------------------
                                   Title: Associate Vice President for Research
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