Fluorescence detection techniques for protein kinase assay

Traditional methods for protein kinase (PK) assay are mainly based on use of P-32-labeled adenosine triphosphate (ATP); applications of such methods are, however, hampered by radioactive waste and short half-life of P-32-labeled ATP. Therefore non-radioactive methods, such as fluorescence detection techniques are good alternative. In this review, we describe the principles of four fluorescence techniques (fluorescence intensity endpoint measurement, fluorescence resonance energy transfer (FRET), fluorescence polarization (FP), and fluorescence lifetime imaging) and provide an overview of applications of these fluorescence detection techniques in protein kinase assay, underlining their relative advantages and limitations. Research trends in this field are also highlighted.