The invention discloses a novel method for
beacon-free detection of T4 PNKP (T4
polynucleotide kinase) /
phosphatase and an inhibitor of T4 PNKP /
phosphatase on the basis of fluorescent
copper nanoparticles. The method is implemented according to steps as follows: 1), a hairpin probe modified by 3'-terminal
phosphorylation is designed, and 5' terminal is a sequence containing a base T; 2), the probe is diluted to the concentration being 100-1,000 nM with a
Tris-HCl
buffer solution, certain quantities of T4 PNKP,
Klenow Fragment and dNTPs are mixed with the probe, and the mixture reacts at the temperature of 37 DEG C for 40-150 minutes; 3), the reaction liquid is diluted to form an
MOPS buffer
system, and
copper sulfate and
sodium ascorbate are added and react for 1-30 minutes at the
room temperature; 4), the
fluorescence strength of the finally obtained reaction liquid is detected with a
fluorescence instrument, and a corresponding relation between the
fluorescence strength of the
system and T4 PNKP concentration is obtained. According to the method, the operation is simple, the cost is low, the sensitivity is high, the selectivity is good, T4 PNKP and the inhibitor can be quantitatively detected and screened, and a potential application value is provided for establishment of other terminal modification
enzyme detection methods and molecular biological diagnosis.