Click Chemistry Mediated Eu-Tagging: Activity-Based Specific Quantification and Simultaneous Activity Evaluation of CYP3A4 Using Eu-153 Species-Unspecific Isotope Dilution Inductively Coupled Plasma Mass Spectrometry
- 化学化工－已发表论文 
P450 3A4 (CYP3A4) is one of the most important isoforms in the human cytochrome P450 superfamily. It was used as an example in this proof-of-concept study in order to demonstrate an activity-based labeling and then click chemistry (CC) mediated element-tagging strategy for simultaneously specific quantification and activity measurement of an enzyme using species-unspecific isotope dilution inductively coupled plasma mass spectrometry (SUID ICPMS). A dual functional hexynylated 17 alpha-ethynylestradiol activity-based probe was synthesized for specifically labeling CYP3A4 and then CC-mediated Eu-tagging with an azido-DOTA-Eu complex for CYP3A4 quantification and activity measurement in human liver microsome and serum samples using Eu-153 SUID ICPMS. The LOD (3 sigma) of CYP3A4 reached 20.3 fmol when monitoring Eu-151/153 ICPMS signals, in addition to the merits of specificity and simultaneous activity measurement achieved. We believe that this activity-based CC-mediated element-tagging strategy will liberate more potential advantages of ICPMS in bioanalysis.