Sunkersett M R, Grimsey I M, Doughty S W, Osborn J C, York P, Rowe R C
School of Pharmacy, University of Bradford, West Yorkshire, BD7 1DP, Bradford, UK.
Eur J Pharm Sci. 2001 May;13(2):219-25. doi: 10.1016/s0928-0987(01)00105-1.
The surface energetic parameters of carbamazepine and paracetamol have been studied using inverse gas chromatography modified to produce dry and ambient conditions within the column. The values of the dispersive component of the surface free energy (gamma(S)D) do not change significantly at the increased relative humidity. In contrast the specific component of the free energy of adsorption (-DeltaG(A)SP) as measured by polar probes, can either remain constant or decrease by up to 10%, depending on the material and the probe. This indicates that an increase in the relative humidity causes a decrease in the surface energetics of the powder surface. It is proposed that where the water molecules are adsorbing to the same sites as the polar probes, the interaction of these probes with the surface is decreased. To identify these sites, the preferential interaction of each probe, including water, with the drug molecule has been modelled.
利用经改进可在柱内产生干燥和环境条件的反相气相色谱法，对卡马西平和对乙酰氨基酚的表面能参数进行了研究。表面自由能的分散成分（γ(S)D）的值在相对湿度增加时没有显著变化。相比之下，通过极性探针测量的吸附自由能的特定成分（-ΔG(A)SP），根据材料和探针的不同，可能保持不变或降低多达10%。这表明相对湿度的增加会导致粉末表面的表面能降低。有人提出，当水分子与极性探针吸附在相同位置时，这些探针与表面的相互作用会减弱。为了识别这些位置，已对包括水在内的每种探针与药物分子的优先相互作用进行了建模。
