Yarmola E G, Zarudnaya M I
Institute of Molecular Genetics, USSR Academy of Sciences, Moscow.
J Biomol Struct Dyn. 1985 Feb;2(5):981-93. doi: 10.1080/07391102.1985.10507614.
A simple osmometer with nuclear filters (polymer films with pores of a preset diameter) were used to measure the osmotic pressure of Col E1 plasmid DNA solutions in the concentration range of 1-4 mg/ml DNA. Linear and open circular DNA forms proved to have the same osmotic pressure within the experimental accuracy. The results of the measurements were used for calculating the second virial coefficient A2 of the solution of DNA segments and the effective chain diameter d eff in the ionic strength range of 10(-2)-0.1 M. As the ionic strength is lowered from 0.1 to 10(-2) M the effective diameter of DNA increases from 80 to 220 A. The results are in rather good agreement with theory and with other experimental data.
使用带有核过滤器（具有预设直径孔隙的聚合物薄膜）的简单渗透计来测量浓度范围为1-4mg/ml DNA的Col E1质粒DNA溶液的渗透压。在实验精度范围内，线性和开环DNA形式被证明具有相同的渗透压。测量结果用于计算DNA片段溶液的第二维里系数A2以及离子强度范围为10^(-2)-0.1M时的有效链直径d eff。随着离子强度从0.1M降低到10^(-2)M，DNA的有效直径从80埃增加到220埃。结果与理论以及其他实验数据相当吻合。
