Salivary tracer Technique

Noninvasive in vivo method

The majority of methods that are currently used to study gastric emptying in humans (e.g. scintigraphy, magnet resonance imaging MRI) are either invasive or costly and complex. Even rather simple methods such as the administration of liquid paracetamol with subsequent blood sampling are limited by the need of trained staff, high clinical regulations and the invasiveness of blood sampling. For this reason, we developed a new method to investigate gastric emptying by measuring the concentrations of a marker in the human saliva. Caffeine was selected as a promising marker as it is known to be absorbed quickly in the human intestine and it quickly appears in the saliva with good and reliable blood/saliva correlation.


  1. M. Sager, M. Grimm, P. Jedamzik, S. Merdivan, M.-L. Kromrey, M. Hasan, M. Koziolek, M. V. Tzvetkov, W. Weitschies. 2019. Combined application of MRI and the salivary tracer technique to determine the in vivo disintegration time of immediate release formulation administered to healthy, fasted subjects. Mol. Pharm. 16 (2019) 1782-1786

  2. M. Sager, P. Jedamzik, S. Merdivan, M. Grimm, F. Schneider, M.-L. Kromrey, M. Hasan, S. Oswald, J. Kühn, M. Koziolek, W. Weitschies. Low dose caffeine as a salivary tracer for the determination of gastric water emptying in fed and fasted state: A MRI validation study. Eur. J. Pharm. Biopharm. 127 (2018) 443-452

  3. M. Sager, M. Grimm, P. Aude, P. Schick, S. Merdivan, M. Hasan, M.-L. Kromrey, A. Sivert, H. Benameur, M. Koziolek, M. V. Tzvetkov, W. Weitschies. In Vivo Characterization of EnTRinsicTM Drug Delivery Technology Capsule after Intake in Fed State: A Cross-Validation Approach Using Salivary Tracer Technique in Comparison to MRI J. Control. Release 313 (2019) 24-32.

  4. M. Sager, P. Schick, M. Mischek, C. Schulze, M. Hasan, M.-L. Kromrey, H. Benameur, M. Wendler, M.V. Tzevtkov, W. Weitschies, M. Koziolek. Comparison of In Vitro and In Vivo Results Using the GastroDuo and the Salivary Tracer Technique: Immediate Release Dosage Forms under Fasting Conditions Pharmaceutics 3 (2019) 1-21.

Institute of Pharmacy

 UNiversity of Greifswald