Simple purification of recovered [18O]H2O by UV, ozone, and solid-phase extraction methods

Area of Science:

• Radiochemistry
• Nuclear Medicine
• Water Purification

Background:

• High purity heavy water enriched in oxygen-18 ([18O]H2O) is crucial for producing positron emission tomography (PET) radioisotopes.
• Organic and inorganic impurities in [18O]H2O can negatively impact radioisotope production efficiency and radiopharmaceutical quality.

Purpose of the Study:

• To develop and optimize methods for removing organic, metallic, and ionic impurities from recovered [18O]H2O.
• To evaluate the effectiveness of purification techniques for enhancing [18O]H2O quality for downstream applications.

Main Methods:

• Utilized UV irradiation to remove low-boiling point organic impurities (e.g., acetonitrile, acetone) from [18O]H2O.
• Employed a combination of UV irradiation and ozone purging to efficiently remove high-boiling point organic impurities (e.g., ethanol, methanol).
• Implemented solid-phase extraction (SPE) following UV irradiation to eliminate all residual organic and inorganic impurities.

Main Results:

• UV irradiation effectively removed low-boiling point impurities within 4 hours with minimal mass loss.
• Combined UV irradiation and ozone purging accelerated the removal of high-boiling point impurities.
• The optimized purification process yielded high-purity [18O]H2O, resulting in a saturation yield of 128.62+/-15.6 mCi/microA for [18F]fluoride and 49.8+/-12.7% radiochemical yield for [18F]fluorodeoxyglucose.

Conclusions:

• Developed a multi-step purification strategy combining UV irradiation and SPE for effective removal of diverse impurities from [18O]H2O.
• The purified [18O]H2O significantly enhances the production efficiency of [18F]fluoride and radiopharmaceuticals, crucial for PET imaging.