Cytochrome P450 1A2 phenotyping for student laboratories


  • Sandra Priller Institute of Pharmacy and Food Chemistry, Julius-Maximilians-Universitat Wurzburg, Am Hubland, D-97074, Wurzburg,Germany.
  • Matthias Unger Institute of Pharmacy and Food Chemistry, Julius-Maximilians-Universitat Wurzburg, Am Hubland, D-97074, Wurzburg,Germany
  • Ulrike Holzgrabe Institut fur Pharmazie und Lebensmittelchemie, Am Hubland, D-97074, Wurzburg, Germany,


Clinical Pharmacy, CYP1A2, cytochrome P450, HPLC, phenotyping, laboratory teaching


The purpose of this research is to impart basic knowledge about the cytochrome P450 metabolism of xenobiotics and its meaning for pharmaceutical and medical problems by means of experiment-led learning. The teaching approach includes anexperimental part and bibliographic investigations as well as a discussion of the obtained results. The experimental work describes two simple methods for phenotyping cytochrome P450 1A2 in humans by HPLC – UV measurement of caffeine and its main metabolite paraxanthine in urine and saliva.These simple and inexpensive methods are applicable to demonstrate the importance of cytochrome P450 enzymes concerning drug inefficacy, drug– drug interactions and adverse drug reactions. Two simple and fast HPLC – UV methods for phenotyping cytochrome P450 1A2 in humans are presented. Using these methods, probands can be classified into poor and fast metabolisers by the determination of the paraxanthine/caffeine ratio in saliva and urine. Since our HPLC methods are inexpensive and simple to carry out, the experiments are particularly suitable for pharmaceutical and medical student laboratories. 


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How to Cite

Priller, S., Unger, M., & Holzgrabe, U. (2018). Cytochrome P450 1A2 phenotyping for student laboratories. Pharmacy Education, 5(2). Retrieved from



Research Article