HELLENIC JOURNAL OF NUCLEAR MEDICINE, vol.12, no.1, pp.59-62, 2009 (SCI-Expanded)
This prospective study was aimed to assess inter- and intra-operator variability during routine quality control (QC) procedure for technetium-99m mercaptoacetyl triglycine (Tc-99m-MAG3) instant kit formulation. A total of 160 QC analyses with thin layer chromatography (TLC) for 20 separate MAG3 reconstitutions were performed by 2 radiochemists. The percentage of free and hydrolysed Tc-99m as well as binding efficiency, were calculated according to standard TLC. Each QC analysis was done using silica gel (SG), silica acrylic (SA), Whatman 1 (W1) and Whatman 3 (W3) TLC strips separately at 1h, following labeling MAG3 instant kit with Tc-99m-pertechnetate. To assess the radiochemical stability of Tc-99m-MAG3, the same analysis was performed 4h after kit reconstitution. Visual confirmation for QC with scintigraphy was also performed. At both time points, each radio-chemist repeated all the procedure twice for each of the TLC paper types to analyze the intra-operator reliability. Crombach's Test was used for the reliability analysis. High inter-operator correlation ratios (range: 0.821-0.920) per each TLC strip were found where the highest concordance rate was 0.921 for SA. Each TLC strip showed adequate kit reconstitution with acceptable free and hydrolysed Tc-99m percentages both at 1 and 4h analyses, along with high binding efficiency values of 94.3 +/- 2.9 and 92.5 +/- 1.9 at 1 and 4h respectively. Intra-observers reliability showed almost equal high concordance rates (range: 0.888-0.961) for all types of strips. In conclusion, all kinds of ITLC/TLC strips were reliable to assess stability of the radiopharmaceutical at 1 and 4 h while analysis with the SA strip had the highest concordence rate. Inter- and intra-operator QC was also reliable.