RT Journal Article SR Electronic T1 Rapid Instant Thin-Layer Chromatography System for Determining the Radiochemical Purity of 68Ga-DOTATATE JF Journal of Nuclear Medicine Technology JO J. Nucl. Med. Technol. FD Society of Nuclear Medicine SP 285 OP 287 DO 10.2967/jnmt.117.200873 VO 46 IS 3 A1 Bornholdt, Michael G. A1 Woelfel, Kayla M. A1 Fang, Ping A1 Jacobson, Mark S. A1 Hung, Joseph C. YR 2018 UL http://tech.snmjournals.org/content/46/3/285.abstract AB The objective of this study was to develop instant thin-layer chromatography (ITLC) conditions for the determination of radiochemical purity of 68Ga-DOTATATE in a shorter time period than those stated in the NETSPOT (Advanced Accelerator Applications, Saint-Genis-Pouilly, France; AAA) kit package insert (PI). A faster ITLC system is needed to reduce the 48- to 50-min development time so that more radioactivity is available for single patient use and wait times are shorter in the event of kit failure. Methods: Variations of the PI mobile system were evaluated with microfiber chromatography paper impregnated with silica gel (ITLC-SG). After a more suitable mobile system was identified, evaluation began by attempting to shorten the 10-cm development distance to 7, 8, and 9 cm. Results: Experiments using variations of PI mobile phase showed that increasing the proportion of methanol in the mobile phase decreased development time. Additionally, if the ratio of 1 M ammonium acetate was reduced to 10% or less, retention factor values fall outside specification. Reducing the development distance shortened development time as expected; however, it also affected the resolution aspect of the radiochromatogram. Conclusion: The fastest developing ITLC system, which maintained resolution and peak shape, was methanol:1 M ammonium acetate (80:20 V/V) with ITLC-SG using a development distance of 8 cm.