PT - JOURNAL ARTICLE AU - Eggert, Laura A. AU - Dick, Michael D. AU - Mahoney, Douglas W. AU - Olson, Joseph P. AU - Werner, Gregory L. AU - Hung, Joseph C. TI - A Rapid Radiochemical Purity Testing Method for <sup>99m</sup>Tc-Tetrofosmin AID - 10.2967/jnmt.109.070573 DP - 2010 Jun 01 TA - Journal of Nuclear Medicine Technology PG - 81--84 VI - 38 IP - 2 4099 - http://tech.snmjournals.org/content/38/2/81.short 4100 - http://tech.snmjournals.org/content/38/2/81.full SO - J. Nucl. Med. Technol.2010 Jun 01; 38 AB - The standard radiochemical purity (RCP) testing method for 99mTc-tetrofosmin as described in the package insert requires extensive time (20–30 min) and considerable skill to achieve accurate results. Additionally, the instant thin-layer chromatography strip impregnated with silica gel (2×20 cm) used in the standard method will not be commercially available in the future. The purpose of this study was to evaluate whether a method developed by our laboratory for RCP testing of 99mTc-sestamibi could also be used as an alternative method for the RCP assay of 99mTc-tetrofosmin. Methods: The alternative RCP testing system consisted of a precut paper strip (1×8.5 cm) from solvent saturation pads (Pall Corp.) as the stationary phase, with 1:1 chloroform:tetrahydrofuran used as the mobile phase. To validate the reliability of the alternative method, RCP values from 17 kit preparations were compared with the 2 methods. Kits were reconstituted according to the package insert instructions, and 4 additions of 99mTc-sodium pertechnetate were purposely added to create trials with RCP values below the accepted limit of 90% purity. Results: Two hundred four trials (100 of which were replicated) were run from the 17 kit preparations. Sixty-four (31%) of the 204 trials were below 90% purity based on the standard method. The overall agreement between the standard and alternative methods was 94% (192/204). The sensitivity of the alternative method for unacceptable RCP limits was 86% (55/64), and the specificity for acceptable RCP values was 98% (137/140). The agreement between the replicated trials of the alternative method was 99% (99/100), and for the standard method it was 92% (92/100). Conclusion: The standard method proved to be a much slower method and requires much more precision and attention. The alternative method is much faster, is easier, requires less attention to the solvent-development process, and can be used for RCP testing of both 99mTc-tetrofosmin and 99mTc-sestamibi. Furthermore, the stationary phase is much more readily available, is not moisture-sensitive, and is less susceptible to operator technique. Our method is accurate in determining the RCP value of 99mTc-tetrofosmin and is a better RCP testing method for 99mTc-tetrofosmin.