Rapid Purification and Formulation of Radiopharmaceuticals via Thin-Layer Chromatography

Area of Science:

• Radiochemistry
• Pharmaceutical Sciences
• Analytical Chemistry

Background:

• Radiopharmaceutical purification traditionally requires high-capacity chromatography (e.g., radio-HPLC) due to large reagent quantities and impurities.
• Organic solvents used in purification necessitate additional reformulation steps for injectable radiopharmaceuticals.
• Microscale radiosynthesis reduces reagent mass and impurities, enabling simpler purification but often still relies on expensive HPLC systems.

Purpose of the Study:

• To demonstrate the feasibility of using radio-thin layer chromatography (radio-TLC) for radiopharmaceutical purification.
• To evaluate radio-TLC as a compact, cost-effective alternative to HPLC in microscale radiosynthesis.
• To assess the yield, purity, and specific activity of radiopharmaceuticals purified by radio-TLC.

Main Methods:

• Development and application of a radio-TLC method for radiopharmaceutical purification.
• Purification of clinical scale batches of [18F]PBR-06 and [18F]Fallypride.
• Comparison of radio-TLC performance against conventional radio-HPLC methods.

Main Results:

• Radio-TLC successfully purified radiopharmaceuticals with high yield, purity, and specific activity.
• The technique offers high-resolution and high-speed separation in a compact, low-cost setup.
• No downstream reformulation step was required after radio-TLC purification.

Conclusions:

• Radio-TLC is a viable and advantageous technique for radiopharmaceutical purification, especially in microscale radiosynthesis.
• Automating radio-TLC could significantly enhance purification efficiency in microfluidic radiochemistry systems.
• This method simplifies the purification process, reduces costs, and eliminates the need for reformulation.