Estimation of octanol-water partition coefficients for neutral and weakly acidic compounds by microemulsion electrokinetic chromatography using dynamically coated capillary columns.

J Chromatogr B Analyt Technol Biomed Life Sci

Discovery Technologies, Pfizer Global Research and Development, Ann Arbor Laboratories, 2800 Plymouth Road, Ann Arbor, MI 48105, USA.

Published: August 2003

Microemulsion electrokinetic chromatography (MEEKC) using dynamically coated capillary columns is shown to be suitable for estimating the octanol-water partition coefficient (log P) for neutral and weakly acidic compounds at pH 3. The solvation parameter model is used to demonstrate that the retention properties of sodium dodecyl sulfate (1.4% w/v), n-butanol (8% v/v) and n-heptane (1.2% v/v) microemulsion are strongly correlated with the octanol-water partition system. For compounds of varied structure and log P values from 0.3 to 5.15, the correlation model is able to estimate log P to better than 0.25 log units. The dynamically coated columns consisting of a bilayer of poly(vinylsulfonate) adsorbed on top of polybrene provide a suitable electroosmotic flow at pH 3 without interfering in the retention properties of the microemulsion. For automated measurements the microemulsion run buffer should be replenished after 10 runs to maintain a stable cycle time and the coated columns replaced after 40-70 runs, depending on sample properties.

Download full-text PDF

Source
http://dx.doi.org/10.1016/s1570-0232(03)00321-0DOI Listing

Publication Analysis

Top Keywords

octanol-water partition
12
dynamically coated
12
neutral weakly
8
weakly acidic
8
acidic compounds
8
microemulsion electrokinetic
8
electrokinetic chromatography
8
coated capillary
8
capillary columns
8
retention properties
8

Similar Publications

Unlocking new possibilities in ionic thermoelectric materials: a machine learning perspective.

Natl Sci Rev

January 2025

Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.

The high thermopower of ionic thermoelectric (-TE) materials holds promise for miniaturized waste-heat recovery devices and thermal sensors. However, progress is hampered by laborious trial-and-error experimentations, which lack theoretical underpinning. Herein, by introducing the simplified molecular-input line-entry system, we have addressed the challenge posed by the inconsistency of -TE material types, and present a machine learning model that evaluates the Seebeck coefficient with an of 0.

View Article and Find Full Text PDF

In this article, we present the concept of extended Seidel energy by employing a generalized extended matrix to study various molecular properties, including the Kovats retention index, boiling point, enthalpy of formation, entropy, acentric factor, and octanol-water partition coefficient. Our research broadens the scope of energy matrices in graph theory, with a particular emphasis on Sombor energy, reduced Sombor energy, average Sombor energy, Banhatti Sombor energy and reduced Banhatti Sombor energy. We examined the correlation of these graph-based energy descriptors with the thermodynamic properties of Benzenoid hydrocarbons (BHC), uncovering strong relationships between these indices and different molecular attributes.

View Article and Find Full Text PDF

Reversed-phase liquid chromatography (RPLC) offers significant advantages over traditional methods for estimating octanol-water partition constants, which are a critical parameter in drug discovery. In contrast to classical methods for determining the octanol-water partition constant, such as shake-flask techniques, RPLC is less time-consuming and easier to automate. In this study, we explored three alternative organic solvent modifiers: acetone, 2-propanol, and tetrahydrofuran for the indirect determination of the octanol-water partition constant for neutral compounds by RPLC using either isocratic retention factors or retention factors extrapolated to 100 % water for several stationary phases.

View Article and Find Full Text PDF

Activation of persulfates on carbon nanotubes for water decontamination: Is the non-radical process consistently considered across different pH levels?

J Hazard Mater

December 2024

State Key Laboratory of Hydraulics and Mountain River Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China.

Carbon nanotubes-driven persulfates oxidation processes (CNTs/PS) have been extensively studied for environmental remediation. Solution pH is one of the main factors affecting wastewater treatment, but it is often overlooked. Herein, we report the effect laws of pH on the mechanism of peroxymonosulfate (PMS) or peroxydisulfate (PDS) activation by CNTs.

View Article and Find Full Text PDF

Modifying the backbone of 24-atom macrocycles allows tailoring of physical properties (octanol-water partition coefficients, log ) while conserving both conformation and the barrier to dynamic, hinge-like motion. Structure is determined by 1D and 2D NMR spectroscopy. The barrier can be subtly tuned by modifications that appear to preclude fully revolute motion and efficient π-stacking of the two subunits.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!