A long-lived luminescent probe to sensitively detect arylamine N-acetyltransferase (NAT) activity of cells.

Arylamine N-acetyltransferase (NAT) is an important phase II metabolizing enzyme that influences drug efficacy and adverse effects. Here, we report a long-lived luminescent lanthanide complex as a probe for NAT, employing an intraligand photoinduced electron transfer strategy. The probe shows approximately 100-fold increase of luminescence upon N-acetylation catalyzed by NAT, with relatively high specificity for NAT2 over NAT1. It is the first NAT probe that is suitable for sensitive, homogeneous, and rapid detection of NAT activity of recombinant enzyme or cell lysate, and is expected to be useful for drug discovery and clinical diagnosis.