The development of chiral stationary phases with high enantioselectivity remains a critical challenge in analytical separations. In this study, a hydroxypropyl-β-cyclodextrin (HP-β-CD) functionalized monolithic capillary column was prepared via a one-pot sequential strategy and evaluated for its ability to resolve enantiomers of structurally diverse pharmaceutical compounds using capillary electrochromatography (CEC). The synthesis involved the in situ formation of GMA-HP-β-CD through a DBU-catalyzed ring-opening reaction between HP-β-CD and glycidyl methacrylate, followed by direct copolymerization with EDMA and AMPS in a porogenic mixture of DMSO and n-hexanol. This integrated approach ensured efficient functionalization and homogeneous network formation without intermediate purification steps.
Optimization of the polymerization conditions revealed that a 62.5% n-hexanol content in the porogenic solvent system yielded a monolith with optimal morphological uniformity and permeability. A crosslinker ratio of 24% EDMA provided sufficient rigidity while maintaining adequate flow characteristics. Polymerization at 60 °C produced a stable, porous structure confirmed by SEM imaging, showing interconnected large through pores and abundant microscale features contributing to high surface area (43.3 m²/g). FT-IR analysis verified the presence of HP-β-CD moieties in the final matrix, with characteristic peaks at 943 and 1083 cm⁻¹ absent in blank monoliths but present in the functionalized version.
The monolith was tested against six chiral drugs: pindolol, clorprenaline, tulobuterol, clenbuterol, propranolol, and tropicamide. Baseline separation was achieved for pindolol (Rs = 1.62), clorprenaline (Rs = 1.73), and tropicamide (Rs = 1.55), indicating strong chiral recognition capability. Partial resolution was observed for propranolol (Rs = 0.53), clenbuterol (Rs = 0.84), and tulobuterol (Rs = 0.53). Notably, the performance of the HP-β-CD monolith surpassed that of conventional β-CD-based systems for certain analytes, particularly those with extended planar aromatic structures.
Comparative studies highlighted the role of molecular geometry in enantioselective interactions. Pindolol and propranolol, both containing rigid, conjugated benzene rings, exhibited significantly improved resolution on the HP-β-CD monolith. The larger hydrophobic cavity of HP-β-CD allows better accommodation of bulky, polycyclic molecules, enabling more defined inclusion complexes. Additionally, restricted rotation within the cavity enhances differential binding affinities between enantiomers. For substituted phenyl compounds like clenbuterol—where chlorine and amino groups extend the conjugated system—the enhanced planarity likely facilitates stronger π–π stacking and van der Waals interactions, leading to superior separation compared to other CD derivatives.PDZK1 Antibody site
This work confirms that HP-β-CD functionalized monoliths offer distinct advantages in CEC for chiral drug analysis, especially when dealing with complex, rigid molecules.JAK3 Antibody Epigenetic Reader Domain The one-pot synthetic method not only simplifies preparation but also ensures consistent functional group distribution.PMID:34990513 Future applications may include the screening of chiral metabolites, enantiomeric impurities in drug formulations, and the development of high-throughput platforms for pharmaceutical quality control. The results underscore the importance of tailored cyclodextrin chemistry in advancing monolithic stationary phase technology for modern chromatographic challenges.MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com
