Violon D
Invest Radiol. 1997 Feb;32(2):126-30. doi: 10.1097/00004424-199702000-00009.
The solvent-accessible surface areas of different monomer nonionic contrast media were calculated for different probe radii. By correlating these areas with an experimental (octanol/water partition coefficient) and a calculated parameter (COMB-C), implications for the radius of the probe volume are pointed out.
The solvent-accessible surface areas of seven monomer nonionic iodinated contrast media were calculated with GEPOL (a program able to calculate various molecular surfaces and volumes) for a wide range of probe radii of the solvent. These areas were correlated with the octanol/ water partition coefficient and COMB-C, a parameter describing the spatial distribution of the hydrophilic elements of a molecule.
The correlation coefficients of the solvent-accessible surface areas (determined with the different probe radii) with the octanol/water partition coefficient and of the solvent-accessible surface areas (determined with the same probe radii) with COMB-C were good. This correlation was better for probe raddi of 3 A or more.
COMB-C, a parameter designed earlier, correlated well with the hydrophilia of a monomer nonionic contrast molecule. It was shown that a probe radius of at least 3 A should be used when correlations with hydrophilic characteristics are studied, rather than a probe radius of 1.5 A, which is generally used in assessment of solubilities of molecules in biologic environment. Implications are discussed.
针对不同的探针半径，计算了不同单体非离子型造影剂的溶剂可及表面积。通过将这些面积与实验参数（正辛醇/水分配系数）和计算参数（COMB - C）相关联，指出了探针体积半径的意义。
使用GEPOL（一个能够计算各种分子表面和体积的程序），针对溶剂的广泛探针半径范围，计算了七种单体非离子型碘化造影剂的溶剂可及表面积。这些面积与正辛醇/水分配系数以及COMB - C（一个描述分子亲水元素空间分布的参数）相关联。
溶剂可及表面积（由不同探针半径确定）与正辛醇/水分配系数之间以及溶剂可及表面积（由相同探针半径确定）与COMB - C之间的相关系数良好。对于3埃或更大的探针半径，这种相关性更好。
先前设计的参数COMB - C与单体非离子型造影剂分子的亲水性相关性良好。结果表明，在研究与亲水特性的相关性时，应使用至少3埃的探针半径，而不是通常用于评估分子在生物环境中溶解度的1.5埃探针半径。对其意义进行了讨论。
