K(+) , Na(+) , and Mg(2+) on DNA translocation in silicon nitride nanopores.
K(+) , Na(+) , and Mg(2+) on DNA translocation in silicon nitride nanopores.
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DOI：
10.1002/elps.201200165
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发表时间：
2012-12
期刊：
影响因子：
2.9
通讯作者：
Li, Jiali
中科院分区：
文献类型：
--
作者：
Uplinger, James;Thomas, Brian;Rollings, Ryan;Fologea, Daniel;McNabb, David;Li, Jiali
关键词：
在这项工作中，我们报告了盐浓度和阳离子种类如何影响偏压氮化硅纳米孔中的 DNA 易位。在含有 KCl、NaCl 和 MgCl2 的盐溶液中测量线性、环状和超螺旋形式的双链 DNA (dsDNA) 的易位。随着 KCl 浓度从 1M 降低至 0.1M，DNA 分子通过纳米孔所需的时间更短，折叠构型中易位的频率降低，表明 DNA 电泳迁移率和 DNA 持久长度增加。当盐浓度保持在 1M，但用 Na+ 代替 K+ 时，观察到更长的 DNA 易位时间 (td)。添加低浓度的 MgCl2 和 1.6M KCl 会导致 td 更长，并且分支形式的超螺旋 DNA 分子的频率增加。这些观察结果与 Na+ 和 Mg2+ 比 K+ 更强的抗衡离子电荷筛选能力一致。此外，我们通过 PCR 扩增和凝胶电泳证明，双链 DNA 分子确实通过约 10 nm 纳米孔易位。我们还将氮化硅纳米孔在单分子水平上测量的 DNA 迁移率和构象对 KCl 浓度和阳离子种类的依赖性与现有的基于本体的实验结果和理论预测进行了比较。
In this work we report on how salt concentration and cation species affect DNA translocation in voltage-biased silicon nitride nanopores. The translocation of double-stranded DNA (dsDNA) in linear, circular, and supercoiled forms was measured in salt solutions containing KCl, NaCl, and MgCl2. As the KCl concentrations were decreased from 1M to 0.1M, the time taken by a DNA molecule to pass through a nanopore was shorter and the frequency of the translocation in a folded configuration was reduced, suggesting an increase in DNA electrophoretic mobility and DNA persistence length. When the salt concentration was kept at 1M, but replacing K+ with Na+, longer DNA translocation times (td) were observed. The addition of low concentrations of MgCl2 with 1.6M KCl resulted in longer td and an increased frequency of supercoiled DNA molecules in a branched form. These observations were consistent with the greater counterion charge screening ability of Na+ and Mg2+ as compared to K+. In addition, we demonstrated that dsDNA molecules indeed translocated through a ~10 nm nanopore by PCR amplification and gel electrophoresis. We also compared the dependence of DNA mobility and conformation on KCl concentration and cation species measured at single molecule level by silicon nitride nanopores with existing bulk-based experimental results and theoretical predictions.
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影响因子：
10.8
作者：
Fologea, D;Gershow, M;Li, JL
通讯作者：
Li, JL
影响因子：
10.8
作者：
Fologea, D;Uplinger, J;Li, JL
通讯作者：
Li, JL
DOI：
10.1073/pnas.0911500106
发表时间：
2009-12-01
影响因子：
11.1
作者：
Evrin, Cecile;Clarke, Pippa;Speck, Christian
通讯作者：
Speck, Christian
影响因子：
3.4
作者：
Ahmad, R;Arakawa, H;Tajmir-Riahi, HA
通讯作者：
Tajmir-Riahi, HA
DOI：
10.1088/0953-8984/22/45/454129
发表时间：
2010-11-17
期刊：
Journal of physics. Condensed matter : an Institute of Physics journal
影响因子：
--
作者：
Li J;Talaga DS
通讯作者：
Talaga DS