中国物理B ›› 2023, Vol. 32 ›› Issue (11): 118704-118704.doi: 10.1088/1674-1056/acfaf6
所属专题: SPECIAL TOPIC — Celebrating the 100th Anniversary of Physics Discipline of Northwest University
Jie Zhu(朱洁), Jing Xue(薛菁), Wei Zhao(赵伟), Chen Zhang(张琛), Xiaoqiang Feng(冯晓强), and Kaige Wang(王凯歌)†
Jie Zhu(朱洁), Jing Xue(薛菁), Wei Zhao(赵伟), Chen Zhang(张琛), Xiaoqiang Feng(冯晓强), and Kaige Wang(王凯歌)†
摘要: Interactions between deoxyribonucleic acid (DNA) and metal ions are vital for maintaining life functions, however, there are still unsolved questions about its mechanisms. It is of great practical significance to study these issues for medical chip design, drug development, health care, etc. In this investigation, the conductivity properties of λ -DNA solutions with mono-/divalent metal ions (Na+, K+, Mg2+, and Ca2+) are experimentally studied as they are electrically driven through a 5 μ m microfluidic channel. Experimental data indicate that the conductivities of λ -DNA solutions with metal ions (M+/M2+) basically tend to reduce firstly and then increase as the voltage increases, of which the turning points varied with the metal ions. When the voltage surpasses turning points, the conductivity of λ -DNA-M+ solutions increases with the concentration of metal ions, while that of λ -DNA-M2+ solutions decrease. Moreover, the conductivity of λ -DNA-M2+ solutions is always smaller than that of λ -DNA-M+ solutions, and with high-concentration M2+, it is even smaller than that of the λ -DNA solution. The main reasons for the above findings could be attributed to the polarization of electrodes and different mechanisms of interactions between metal ions and λ -DNA molecules. This investigation is helpful for the precise manipulation of single DNA molecules in micro-/nanofluidic space and the design of new biomedical micro-/nanofluidic sensors.
中图分类号: (DNA)