radiolabeled halogenated

The total value of the sales agreement is at least
$1. Laflin, President and CEO said, "The Company is very pleased to
have completed this agreement and be able to continue our long term cobalt
supply relationship with this customer.

The three-year collaboration with Macrocyclics will focus on
novel chelate structures, linkers and conjugation methods to enable
the use of a wider range of targeting vectors by the research
community.

13c radionuclides

perkinelmer labeled

Find out more at www.

radioisotopes halogenated

This is a
fixed price guaranteed minimum requirements agreement that extends through
December 31, 2007. The use of molecular targeting molecules is an
established and increasingly promising technique that has the
potential to significantly improve the ability to diagnose and treat
disease, including cancer.

Through this collaboration, researchers will have access to
innovative bifunctional chelates and linkers to help them pursue new
avenues of investigation for the diagnosis and treatment of disease.

These sites are from companies that make , manufacture, distribute or sale primarily general-purpose radio and stable isotopes for scientific research.

radiolabeled 12c

Information contained
in forward-looking statements is based on current expectations and is subject
to change. have entered into a research
and development collaboration to develop innovative , bifunctional
chelates for use in molecular imaging and targeted therapeutic
pharmaceuticals.

"Macrocyclics has an innovative scientific team and is a leading
provider of chelates and linkers to the research community," said
Steve West, President of MDS Nordion. MDS Nordion is
part of MDS Inc.

MDS Nordion (TSX:MDS) (NYSE:MDZ)

radiochemical 13c

International Isotopes Inc. Announces Completing a New Long Term Sales Agreement for High Activity Cobalt

Find out more about Macrocyclics by visiting the
website or by calling 1-972-250-2248.

isotec 15n

(OTC Bulletin Board: INIS) is pleased to announce completion of
a new three year sales agreement to supply high activity cobalt to one of the
largest and most diversified industrial corporations in the world."

About International Isotopes Inc. "Our collaboration with
Macrocyclics strengthens MDS Nordion's commitment to expand our
discovery and development services including radiolabelling and
molecular imaging applications for pharmaceutical drug development,
and complement our leadership position in the co-development and
commercial manufacturing of novel radiopharmaceuticals.

deuterated halogenated

Value of the Sales Agreement Is Estimated at Least $1.

chemgas isotope

5 million.

News Editors

OTTAWA----

Innovative compounds to be developed for use in drug discovery,
development and targeted therapies

MDS Nordion and Macrocyclics Inc .

"We are very pleased to be collaborating with MDS Nordion, an
international leader in radioisotope supply and radiopharmaceutical
services for the nuclear medicine industry," said Dean Sherry,
President , Macrocyclics, and Professor of Radiology, University of
Texas - Southwestern Medical Center, Dallas and Professor of
Chemistry, University of Texas, Dallas.

radioisotope radiochemicals

Safe Harbor Statement
Forward -looking statements in this press release are made pursuant to the
safe harbor provision of the federal securities laws.com or by calling
1-888-MDS-7222, 24 hours a day.

precursors perkinelmer

Steve T.

12c saccharides

manufactures a full range of nuclear medicine
calibration and reference standards, manufactures a range of cobalt -60
products such as teletherapy sources, and provides a wide selection of
radioisotopes and radiochemicals for medical devices, calibration, clinical
research, life sciences, and industrial applications.

Actual results may differ materially from the forward-looking
statements.

MDS Nordion and Macrocyclics Announce Research and Development Collaboration

com) is a world leader in
radioisotopes, radiation and related technologies. We are a global, values-driven health and life
sciences company, recognized for our reliability and collaborative
relationships as we help create better outcomes in the treatment of
disease.

3h nucleosides

New chelates will be
assessed with a variety of MDS Nordion radioisotopes including:
yttrium-90, lutetium-177, indium-111 and copper-64.

About Macrocyclics

Macrocyclics is a privately held, Dallas, Texas based company
that conducts research and development, custom cGMP synthesis and
makes accessible to the research community a variety of high purity
ligands for nuclear medicine and magnetic resonance imaging
applications.

13c 3h

Readers are directed to read the risk factors
detailed from time to time in the company's filings with the Securities and
Exchange Commission , including the company's annual report on Form 10-KSB for
the year ending December 31, 2003.mds.

halogenated 13c

For More Information, Contact:
Steve Laflin, President and CEO
(208) 524-5300

(TSX:MDS; NYSE:MDZ) has more than 9,000
highly skilled people in 25 countries.

isotopes radioisotope

Bifunctional chelates are chemical compounds used to
secure a radioisotope to a molecular targeting agent such as a
monoclonal antibody, peptide, or other molecules specific for
biologic receptors.

In addition, sites from research institutions, which develop analytical tools and provide isotope services for research and industry.

3h precursors

The objective is to develop, and make available chelates
that have performance features, such as high efficiency
radiolabelling at room temperature, while maintaining stability
comparable to industry standard chelates.

About MDS Nordion

MDS Nordion (www.mdsintl .

radionuclides 12c

International Isotopes Inc. MDS Inc.

tritium radioisotope

Targeted therapeutic
pharmaceuticals treat disease by directing the treatment to specific
types of cells while seeking to spare healthy tissue and reduce side
effects to the patient.

Also sites from companies that make, manufacture, distribute or sale primarily general-purpose NMR isotopically labeled solvents and other chemicals are listed here .

radiochemicals labeled

5 Million

IDAHO FALLS, Idaho, International
Isotopes Inc. We provide a diverse range of
superior products and services to increase our customers' speed,
precision and productivity in the drug development and disease
diagnosis processes.

microspheres perkinelmer

The Company also
provides a host of analytical, measurement, recycling, and processing services
on a contract basis to clients.

15n labeled

13c isotopes

International Isotopes Inc. Many factors could cause actual results to differ materially from
the forward-looking statements.

nucleosides radiolabeled

"

Molecular imaging is the application of nuclear medicine for the
non-invasive investigation of cellular activity and is increasingly
being used in the drug development process.nordion.