Quantitative distribution studies in animals: cross-validation of radioluminography versus liquid-scintillation measurement

Regul Toxicol Pharmacol. 2000 Apr;31(2 Pt 2):S33-43. doi: 10.1006/rtph.2000.1384.


The results of a cross-validation of the radioluminography (RLG) and liquid scintillation counting (LSC) methods are presented. The methods for the determination of radioactivity concentrations were compared in 16 organs, after administration of (14)C-labeled substances to rats. LSC measurements of two kinds were used as reference methods for RLG: (1) quantitative determination of radioactivity after conventional dissection (interindividual comparison) and (2) quantitative determination of radioactivity in tissue punches taken from the whole-body sections after they had undergone RLG measurement (intraindividual comparison). Blood standards containing known concentrations were used for calibration. For statistical evaluation log-linear regression analysis of paired concentration values and organ-specific 95% confidence intervals of the log-transformed RLG/LSC concentration quotients were compared. For most organs, the slopes of the regression lines and the means of the concentration quotients were within the defined equivalence range of 0.80-1.25. Deviations were distinctly smaller in the intraindividual comparison. For some organs, however, it became clear that found concentrations were affected by self-absorption (RLG) and by differences in sample preparation (LSC). In conclusion, quantification with RLG is a reliable and reproducible method with comparable measurement precision and greater accuracy in respect of tissue localization, compared to LSC (dissection).

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Autoradiography / standards
  • Female
  • Male
  • Radiometry / standards*
  • Radiopharmaceuticals / pharmacokinetics*
  • Rats
  • Reproducibility of Results
  • Scintillation Counting / standards*
  • Sensitivity and Specificity
  • Tissue Distribution


  • Radiopharmaceuticals