A simple label-free electrochemical method for the detection of polynucleotide kinase activity by a peroxidase mimic: TiO₂ nanotube array

Abstract

Here we report the development of a simple label-free electrochemical method for a PNK assay based on the mimic peroxidase character of a prepared TiO2 nanotube array (NTA) and its specific attachment to phosphorylated DNA.

A sensitive electrochemical assay for T4 polynucleotide kinase activity based on titanium dioxide nanotubes and a rolling circle amplification strategy

“…The semicircle portion in an EIS corresponds to the electron-transfer limited process, and the increase of the semicircle diameter indicates the increase of the interfacial electron-transfer resistance ( R et ). 25 As shown in Fig. 2 , compared with bare Au electrode (curve a), the electrode modified with S1 (curves b) shows a larger semicircular domain, implying a high electron transfer resistance.…”

“…Aer being rinsed with washing buffer, modication of the TiO 2 NTs on the phosphorylated S1 (P-S1) was carried out by incubating P-S1 with 5 mL of 0.6 mM TiO 2 NTs solution for 2 h at room temperature to capture TiO 2 NTs on P-S1 based on the specic adsorption of the phosphorylation sites and Ti 4+ , and linkage between TiO 2 NTs and P-S1 (TiO 2 /P-S1/Au) was processed. 25,34,39 With different concentrations of T4 PNK for phosphorylation, the related amounts of TiO 2 /P-S1 were obtained. The TiO 2 /P-S1/Au was washed with washing buffer and stored at 4 C prior to use.…”

“…Compared to the methods mentioned above, electrochemical biosensors have attracted much attention in T4 PNK assay due to high sensitivity, low-cost, low power requirement and high compatibility. [25][26][27][28][29][30][31] Though the progress of these electrochemical approaches have been successfully made for the detection of T4 PNK activity and screening its inhibitors, it still remains a challenge to develop simple, rapid, accurate and sensitive electrochemical methods for T4 PNK activity assay.…”

“…Ti 4+ , TiO 2 and l exonuclease were widely used as identication reagents. 17,25,27,[32][33][34] For instances, Wang et al developed an electrochemical strategy for monitoring the activity and inhibition of T4 PNK based on Ti 4+ mediated signal transition coupled with signal amplication of single wall carbon nanotubes, 32 which a signal amplied method for the electrochemical determination of T4 PNK activity based on the peroxidase-like activity of magnetite microspheres, the specic recognition capabilities of TiO 2 with the phosphate groups of the capture probe and the DNA dendrimer structure for signal amplication. 34 Furthermore, Cui et al and Hou et al, respectively, successfully screened DNA phosphorylation process based on AuNP-mediated l exonuclease cleavage and l exonuclease enzyme reaction and bimolecular beacons-induced signal amplication.…”

A Sensitive Electrochemical Assay for T4 Polynucleotide Kinase Activity Based on Fe3O4@TiO2 And Gold Nanoparticles Hybrid Probe Modified Magnetic Electrode

“…Among these methods, electrochemical assays have attracted increasing attention due to high sensitivity, lowcost, easy miniaturization, and fast response. [26][27][28][29][30][31][32] To improve sensitivity, various nanomaterials are introduced in electrochemical sensors due to the their excellent optical and electric properties, unique structures, and good biocompatibility, such as metal nanoparticles and nanoclusters, carbon nanomaterials, quantum dots (QDs), metal−organic frameworks (MOFs), MXenes, semiconductors nanomaterials, and their nanocomposites. [32][33][34][35][36][37][38][39][40][41][42][43][44] Although great achievements of these electrochemical approaches have been developed for the detection of T4 PNK activity and screening its inhibitors, it still remains a challenge to develop more simple, rapid, accurate and sensitive methods for T4 PNK activity assay.…”