Physicochemical parameters, retention time prediction based

Structure-based prediction software predicts retention times or important physicochemical processes based on chemical structures. Application databases store chromatographic methods for later retrieval and adaptation to new samples with similar structures and physicochemical parameters. 

A second approach is based on physicochemical parameters, used in ACD/LC Simulator. The prediction of RP retention times based on physicochemical parameters assumes that the primary retention mechanism is hydrophobicity of the compound as a function of its ionic form at a given pH. The general approach is given as... 

M. McBrien, E. Kolovanov, and R. Taylor, Highly accurate prediction of retention times in standard gradient chromatographic systems based on physicochemical parameters, March 9-14, 2003, Pittsburgh conference, Orlando, FL. 

In spite of widespread applications, the exact mechanism of retention in reversed-phase chromatography is still controversial. Various theoretical models of retention for RPC were suggested, such as the model using the Hildebrand solubility parameter theory [32,51-53], or the model supported by the concept of molecular connectivity [54], models based on the solvophobic theory [55,56) or on the molecular statistical theory [57j. Unfortunately, sophisticated models introduce a number of physicochemical constants, which are often not known or are difficult and time-consuming to determine, so that such models are not very suitable for rapid prediction of retention data. 

---