Improvement of the high-speed logD assay using an injection marker for the water plug aspiration/injection method.
An improved method for the high-speed assay for logD (HSLogD) employing an injection marker is described. The critical process of HSLogD is automated sampling of the water phase, which prevents contamination from the octanol phase. However, deployment of HSLogD sometimes produces incorrect and inaccurate values compared with data from closely related methods due to low solubility of compounds or instrument problems. Therefore, careful manual inspection of data is needed to confirm the results obtained by this method. To solve this problem, compounds were screened for suitability as injection markers and 2-(4-methoxyphenoxy)-4,8-dimethylquinoline was the most suitable compound examined. Introduction of the injection marker into the process successfully eliminated the need for the tedious and time-consuming manual inspection process.
Nishimura
Ikuko
I
Tsukuba Research Institute, Banyu Pharmaceutical Co, Tsukuba, Ibaraki, Japan. ikuko_nishimura@merck.com
Hirano
Atsushi
A
Yamashita
Taro
T
Fukami
Takehiro
T
D000465:Algorithms; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D008055:Lipids / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D000442:Octanols / Q000737:chemistry; D011804:Quinolines / Q000737:chemistry; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012995:Solubility; D014867:Water / Q000737:chemistry
D008055:Lipids; D000442:Octanols; D011804:Quinolines; D014867:Water