January 31, 2019
Notice Regarding First Domestic Production and Sales Launch of Water-17O,
a Stable Isotope of Oxygen
Taiyo Nippon Sanso Corporation (TNSC) hereby announces that it has succeeded in manufacturing
and launched sales of Japan’s first domestically produced Water-17O*1, a stable isotope of oxygen,as a research reagent. Water-17O is expected to image important brain function-related parameterssuch as imaging of brain fluid dynamics, including cerebral blood flow and cerebrospinal fluid.
1. Background
Hokkaido University Hospital has been moving forward on clinical research using Oxygen -17MRI (17O-MRI) testing*2 for various types of patients. TNSC has been providing the contrast
agents (clinical research reagents and investigational products) used in 17O-MRI testing.
In 17O-MRI testing, viewing the dynamics of Water-17O injected as a contrast agent provides clear
observation of blood flow and enables testing of such matters as cerebral blood flow and vascularpermeability. Compared to nuclear medical scans such as SPECT and PET, 17O-MRI
testing provides higher resolution images without exposure to radiation, so it is expected to beused with infants and pregnant women. Furthermore, by obtaining imaging of fluid dynamics not
only of cerebral blood flow but also cerebrospinal fluid, it enables elucidation of neurologicaldisorders (Alzheimer’s dementia and other cognitive disorders) caused by accumulation ofprotein wastes in the brain and vastly expands the possibilities of fluid dynamics research within
the body.

Img. 1: Left: An image of a brain obtained from a SPECT test
Right: An image of a brain obtained from 17O-MRI testing(Images courtesy of Associate Professor Kohsuke Kudo, Radiology, Central Clinical Facilities, Hokkaido UniversityHospital)2. Production and Sales
TNSC expanded on Japan’s third production plant for Water-18O*3, a stable isotope of oxygen,in Yamaguchi Prefecture in 2013 (annual capacity of 300 kg) and started production of Water 18

O in 2015. Recently, this plant became the first in Japan to successfully produce Water-17O*1,using a by-product gas. Going forward, TNSC will provide a stable supply of high-quality Water17

O produced under strict quality control compliant with GMP.

1) Product① Product name: Water-17O (research reagent)② Concentration: 10 atom% 17O (oxygen atomic ratio)
2) Production plant① Production capacity: Water-17O 30 kg/year (10 atom% 17O)
* R&D currently underway to increase and reinforce production capacity(Produced together with Water-18O 300 kg/year (98 atom% 18O))② Plant location: Shunan Sanso Co., Ltd., Shunan City, Yamaguchi Prefecture3) Commercialization facility① Features: Production and quality control framework compliant with GMP② Plant location: TNSC SI Innovation Center, Tama City, Tokyo
4) Date sales launchedFebruary 1, 2019

Img. 2: Water-17O production
plant at Shunan Sanso Co.,Ltd.

Img. 3: Water-17O commercialization
facility at the TNSC SI Innovation
CenterImg. 4: Exterior packaging ofWater-17O

Glossary*1 TNSC’s Water-17O, a stable isotope of oxygen
A water molecule is a combination of two hydrogen atoms and one oxygen atom, but in Water 17

O, the oxygen atom is not the general oxygen atom with a mass number of 16, but water witha stable isotope of oxygen with a mass number of 17.
Naturally occurring oxygen is composed of three types of stable isotopes, 16O, 17O, and 18O,
with their ratio (oxygen atomic ratio) at 99.76%, 0.04% and 0.2%, respectively. Physiochemical
properties of each of the isotopes are almost identical, making it extremely difficult toconcentrate or separate them. TNSC developed an 18O condensation method through an oxygen
cryogenic distillation technology and has produced Water-18O with a world-leading
concentration of at least 98 atom% since 2004, providing stable supply to PET markets aroundthe world. TNSC has succeeded in Japan’s first production of Water-17O through a by-productgas at the Water-18O production plant. Uses are expected to include clinical research such as
NMR analysis and 17O-MRI testing uses in the medical sector.
*2 17O-MRI testing
Magnetic Resonance Imaging (MRI) is an imaging method that uses powerful magnets andelectromagnetic waves to obtain images of cross-sections of the body. 17O-MRI testing is agraphic testing method that analyzes changes in MRI signals in response to changes in thedegree of concentration of Water-17O within the body.
*3 TNSC’s Water-18O
A water molecule is a combination of two hydrogen atoms and one oxygen atom, but in Water18

O, the oxygen atom is not the general oxygen atom with a mass number of 16, but water witha stable isotope of oxygen with a mass number of 18.
TNSC currently has a Water-18O production capacity of 600 kg/year (total of three Water-18O
production plants) and provides customers around the world with high-quality products
commercialized using production equipment and quality control compliant with GMP. Water 18

O is mainly used in medical sectors around the world as the raw material in the PET diagnostic

reagent 18FDG.
(18FDG: A PET diagnostic reagent consisting of a fluorodeoxyglucose (a glucose analog)
labeled with a 18F positron-emitting radionuclide. 18FDG is accumulated in cancer cells that
actively metabolize glucose, so that a PET scanner can use images of 18FDG distribution within
the body to diagnose cancer.)