The cellular enzyme poly ADP (ADP: adenosine diphosphate)-ribose polymerase-1 (PARP-1) plays key roles in DNA repair. Its activity is closely related to various cancer developments. Detection of PARP-1 activity is significant, however, it is relatively difficult since it lacks superiority property that can be used to detect conveniently. PARP-1 lead to the synthesis of hyperbranched poly (ADP-ribose) polymers (PAR) using nicotinamide adenine dinucleotide (NAD⁺) as substrate during DNA damage repairing. In this paper, we found that hyper-branched PAR increased the steric hindrance and reduced the flux of probe ions effectively in anodic aluminum oxide (AAO) nanochannels. To the best of our knowledge, few papers have been reported that hyper-branched polymer has the similar effects in nanochannels as G-quadruplex DNA. Thus, a novel and simple strategy for PARP-1 detection has been proposed due to its great impacts on the diffusion flux of ferricyanide in AAO. It is also proved that electrostatic repulsion is another important factor to influence the current. The method is label-free, simple and sensitive. Quantitative detection of PARP-1 activity was achieved with the detection limit of 0.006 U, which is lower or comparable to the most reported methods. The method has good accuracy and reproducibility. The strategy has been used to detect PARP-1 activity in real breast cancer cells and to evaluate PARP-1 inhibitors with satisfactory results, indicating that it is a potential powerful tool for clinical diagnosis and drug development in the future.

细胞酶聚ADP（ADP：二磷酸腺苷）-核糖聚合酶-1（PARP-1）在DNA修复中起关键作用。它的活性与各种癌症的发展密切相关。PARP-1活性的检测很重要，但是，由于缺乏可方便检测的优越性，因此相对困难。PARP-1使用烟酰胺腺嘌呤二核苷酸（NAD ⁺）作为DNA损伤修复过程中的底物。在本文中，我们发现在阳极氧化铝（AAO）纳米通道中，超支化PAR可有效增加空间位阻并降低探针离子的通量。据我们所知，很少有论文报道超支化聚合物在纳米通道中具有与G-四链体DNA类似的作用。因此，由于其对AAO中铁氰化物的扩散通量的巨大影响，已经提出了一种新颖且简单的PARP-1检测策略。还证明静电排斥是影响电流的另一个重要因素。该方法无标签，简单且灵敏。PARP-1活性的定量检测达到了0.006 U的检出限，该检出限低于或可与大多数报道的方法相媲美。该方法具有良好的准确性和可重复性。