An electrochemical biosensor for T4 polynucleotide kinase activity assay based on host–guest recognition between phosphate pillar[5]arene@MWCNTs and thionine

. It was also effective in measuring HeLa cell lysate-related T4 polynucleotide kinase activity and inhibitor screening. The proposed method offers a unique sensing platform for kinase activity measurement, holding great potential in nucleotide kinase-target drug development, clinical diagnostics, and inhibitor screening.