Learn More
The focus of this paper is the analysis of circular cylinders through sets of points in three dimensions. This investigation has a number of motivations. Clearly, if a cylinder of radius R and direction t passes through a set of points P , it means also that there is a line of direction t tangent to the sphere of radius R and centered at the points of P .(More)
Immobilised polysaccharide-based chiral stationary phases (CSPs) are chromatographic materials that combine the remarkable enantioselective performance of the polysaccharide derivatives in addition to solvent versatility for enantiomeric resolution. Their behaviour under normal phase conditions and polar organic mode has been quite extensively discussed in(More)
CHIRALPAK IA, CHIRALPAK IB and CHIRALPAK IC are a new generation of chiral packing materials for resolution of enantiomers by chromatography. They are all prepared by chemical immobilisation of the respective polysaccharide derivatives onto a supporting silica matrix. The present article aims to establish an understanding of the global enantioselective(More)
PURPOSE To assess sexual function, satisfaction with life (SWL), and menopause-related symptoms among mid-aged Spanish women. MATERIALS AND METHODS Cross-sectional study of 260 women, aged 40-59, attending the public gynecology consultations completed the 14-item Changes in Sexual Functioning Questionnaire (CSFQ-14), the SWL Scale (SWLS), the Menopause(More)
CHIRALPAK ZWIX(+) and ZWIX(-) are cinchona alkaloid-derived zwitterionic chiral stationary phases (CSPs) containing a chiral sulfonic acid motif which serves as negatively charged interaction site. They are versatile for direct enantiomer resolution of amino acids and many other ampholytic compounds by HPLC. The synergistic double ion-pairing between the(More)
An extensive series of free amino acids and analogs were directly resolved into enantiomers (and stereoisomers where appropriate) by HPLC on zwitterionic chiral stationary phases (Chiralpak ZWIX(+) and Chiralpak ZWIX(-)). The interaction and chiral recognition mechanisms were based on the synergistic double ion-paring process between the analyte and the(More)
CHIRALPAK IA is a new chiral stationary phase containing amylose 3.5-dimethylphenylcarbamate immobilized onto silica gel. It is compatible with the whole range of organic solvents. Its solvent versatility has been thoroughly investigated. The option to use a wide range of solvents, especially the "non-standards" ones, in the mobile phase enables the(More)
CHIRALPAK IC is a new chiral stationary phase (CSP) made by immobilising cellulose tris(3,5-dichlorophenylcarbamate) on silica gel. The chiral selector is distinct from any other commercially available polysaccharide-based CSPs. Apart from its compatibility with the whole series of solvents; this CSP is able to operate under various chromatographic(More)
Sample solubility in the mobile phase and enantioselectivity are key factors in chiral preparative chromatography. In the search for a high throughput process for production of pure enantiomers, the rational design of the mobile phase and the selection of a suitable chiral stationary phase (CSP) are essential. However, one may sometimes be faced with the(More)
The immobilized polysaccharide-derived chiral stationary phases (CSPs) combine the benefits of broad application scope and high preparative potential with CSP robustness and universal solvent compatibility. Strategies for efficient and straightforward method development with these CSPs were previously overviewed. In the current study, six CSPs with(More)