Electrostatic interactions and ionization effect in immobilized artificial membrane retention. A comparative study with octanol-water partitioning.

The present study is a continuation of our efforts to investigate the effect of electrostatic interactions and ionization on immobilized artificial membrane (IAM) retention. The previous set of neutral and basic drugs was extended to include acids and ampholytes and analogous buffer conditions in the mobile phase were used, namely morpholinepropanesulfonic acid and phosphate buffer saline, adjusted at pH 7.4.

Different retention behavior of structurally diverse basic and neutral drugs in immobilized artificial membrane and reversed-phase high performance liquid chromatography: comparison with octanol-water partitioning.

The retention behavior of 43 structurally diverse neutral and basic drugs in immobilized artificial membrane chromatography was investigated and compared to the reversed-phase retention and octanol-water partitioning. IAM chromatography was performed using morpholinepropanesulfonic acid (MOPS) or phosphate buffer saline (PBS) at pH 7.4 as the aqueous component of the mobile phase.

Retention of substituted coumarins using immobilized artificial membrane (IAM) chromatography: a comparative study with n-octanol partitioning and reversed-phase HPLC and TLC.

The chromatographic indices log k(wIAM) have been determined by HPLC on an immobilized artificial membrane column for a set of coumarin derivatives. The investigated compounds contain substituted amidoximes, or substituted heterocycles directly attached to the coumarinic skeleton. The log k(wIAM) values were compared to previously reported data of octanol-water partition coefficients and extrapolated capacity factors determined by reversed phase HPLC and TLC.

Analysis of the interaction of substituted coumarins with the DPPH free radical by means of multivariate statistics.

The interaction of some substituted coumarin derivatives with the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical was analysed by means of multivariate statistics using a variety of molecular descriptors. The compounds contain a conjugated double bond system, which was considered to be an essential structural characteristic for the free-radical scavenging activity. Partial least-square analysis led to an adequate two-component model based on bulk descriptors and the electronic properties concerning atoms involved or next to the double-bond system.