近日，浙江理工大学Li-Zhen Sun团队报道了通过调节pH值的纳米孔操作和单链DNA分子分离。该研究于2026年4月7日发表在《中国高分子科学杂志》上。

pH对静电相互作用的独特调控效应为操控和分离单链DNA（ssDNA）分子提供了强有力的方法。

研究组采用朗之万动力学模拟，探究了在酸性条件下两条ssDNA链——poly(dA)和poly(dT)——通过氮化硅纳米孔的易位动力学。这两条链的关键区别在于它们随pH变化的质子化行为不同。在低pH下，高度质子化的腺嘌呤碱基与同样质子化的纳米孔表面产生排斥相互作用，并受到外加电压的阻滞力，而中性的胸腺嘧啶碱基则没有这些效应。

因此，与poly(dT)相比，poly(dA)在强酸性条件下表现出更低的捕获概率和更慢的易位速度。然而，随着pH升高，两条链之间易位行为的差异逐渐减小。基于它们随pH变化的差异化行为，在低pH下，即使两条等长的poly(dA)和poly(dT)最初混合在纳米孔的同一侧，也可以通过易位策略成功实现分离。

附：英文原文

Title: Nanopore-based Manipulation and Separation of Single-stranded DNA Molecules through Tuning pH Values

Author: Cheng-Kai Zhou, Sheng-Wen Miao, Li-Zhen Sun

Issue&Volume: 2026-04-07

Abstract: The unique regulatory effect of pH on electrostatic interactions offers a powerful approach for manipulating and separating single-stranded DNA (ssDNA) molecules. In this study, we employ Langevin dynamics simulations to investigate the translocation dynamics of two ssDNAs, poly(dA) and poly(dT), through a silicon nitride nanopore under acidic conditions. The key distinction between the two chains is their different pH-dependent protonation. At low pH, the highly protonated adenine bases experience repulsive interactions from the similarly protonated nanopore surface and the retarding force from the external voltage, whereas neutral thymine bases do not. Consequently, compared to poly(dT), poly(dA) exhibits a lower capture probability and slower translocation speed under strongly acidic conditions. However, the difference in the translocation behaviors between the two chains gradually diminishes as the pH increases. Based on their distinct pH-dependent behaviors, poly(dA) and poly(dT) of identical length can be successfully separated through the translocation strategy at low pH, even when they are initially mixed on the same side of the nanopore.

DOI: 10.1007/s10118-026-3640-7

Source: https://www.cjps.org/en/article/doi/10.1007/s10118-026-3640-7/