Objectives: The manufacturer recommends Alumina based TLC–SG/Sodium citrate for RCP estimation of 68Ga-DOTA-TATE (Octreotide) but the method is time consuming and expensive. So the present study was undertaken to investigate if ITLC-SG/Sodium citrate is a better system for determining RCP, which is fast, convenient and cost-effective than the recommended method.

Methods: 68Ga-DOTA-TATE was prepared using commercially available 68Ge/68Ga generator (Obninsk, Russia) which was eluted with 0.1M HCl, and reacted with 40 µg of DOTA-TATE, and heating at 119°C for 15min. The reaction product was purified by C-18 reverse phase column eluted with 1 mL of 99% ethanol.
RCP of 68Ga-DOTA-TATE was estimated by using Alumina based TLC–SG and Sodium Citrate (0.1 M) as the solvent. The RCP was estimated by Instant thin-layer chromatography (ITLC-SG/Sodium citrate 0.1M).

Results: RCP for 68Ga-DOTA-TATE was > 99%, with ITLC-SG, and it takes approximately 1-2 minutes to complete. RCP results were comparable with the recommended method using Alumina based silica gel TLC- but it took approximately 30minutes to complete the procedure. Since half-life of 68Ga is only 68 min, faster RCP methods have definite advantage.

Conclusion: ITLC-SG/Sodium citrate method seems to be as good as the manufacturer recommended method but has the definite advantage of being fast, cost-effective, convenient and reliable.