Comparing the measured affinity of 111In-labeled ligands for cellular receptors by monitoring gamma, beta, or X-ray radiation with three different LigandTracer® devices
LigandTracer instruments measuring high energy photons (gamma-rays), particles (electrons and positrons) and low energy photons (X-rays) are novel semi-automated devices which produce real-time radiotracer-receptor interaction data for measurement of the affinity. The affinities of two different 111In-labeled ligands were measured in three different LigandTracer devices detecting high energy gamma, Auger and internal conversion electrons, or X-rays. The obtained similar uptake/retention patterns (binding curves) show that even at low signal-to-noise ratios (data from Auger and internal conversion electrons, and X-rays), reliable binding data can be captured. This verifies that different devices could be used as alternatives for kinetic evaluation studies for radionuclides emitting different type of radiation.
Keywords111In LigandTracer Yellow LigandTracer White LigandTracer Grey Binding kinetics Affinity
The authors thank Ridgeview Instruments AB for providing the instruments and software for this study. They also thank Assoc. Prof. Karl Anderson, Prof. Vladimir Tolmachev and Prof. Jos Buijs for their effective advice and contribution in the discussion. This work was supported by grants from Swedish Cancer Society and Swedish Research Council.
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