Figure 3: High-pressure liquid chromatogram of gallium-68-DOTA-Tyr3-octreotate. The peaks seen in these two chromatograms were analyzed in ultraviolet channel; therefore, only the solvent signal (0.0–2.0 min) is seen, the DOTA-Tyr3-octreotate signal (5.5 min) and no free gallium-68. The peak seen in both chromatograms (10-12 min) is not related to a substance or free gallium-68, but it is related to the gradient high-pressure liquid chromatography method (used to analyze the sample). The labeling efficiency of the three validation runs was 63.34%, 63.71%, and 64.01%