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Ordering Information
P-CAP is a new bonding technology, primarily used in normal phase, for
the separation of racemic compounds. This CSP technology is based on the reproducible
polymerization of a cyclic diamine from surface of silica. This method offers
maximum protection of the silica and excellent availability of the short chain
polymer ligand that ensures high capacity. The resulting thin, ordered layer
of polymer does not alter the porous structure of the silica. The repeating
chiral moiety offers both structural conformation and hydrogen bonding interactions
as the driving mechanisms. Preparative separations can be run in a variety of
solvents (without any large impact on selectivity) to meet solubility requirements.
As a result of the juxtaposition of the binding sites, molecules with two or
more functional groups demonstrate the best selectivity. Separations have been
run in pure acetone, heptane/ethanol, dichloromethane/methanol and ethylacetate.
P-CAP-DP™ expands the capabilities and is complementary to the
original P-CAP chiral stationary phase, the latter used primarily in normal
phase for separation of racemic compounds. The introduction of the π system,
in combination with the chiral hydrogen bonding capabilities offers new opportunities
for chiral selectivity. The additional bulk from the aromatic rings further
enhances steric effects. P-CAP-DP™ is generally used with two basic mobile
phase systems: (1) normal phase heptane/IPA or ethanol; or (2) the polar organic
mode employing acetonitrile/methanol. Volatile acids and buffers can be used
to enhance peak efficiency when needed or to enhance ion detection for MS platforms.
Additional racemates resolved with high selectivity include hydroxycarboxylic
acids, alcohols, sulfoxides, esters, amides and lactones and N-blocked amino
acids. There are no known limitations on the kind of solvents that can be used
with these phases including halogenated compounds. The well ordered polymer
layer is unaffected by solvent changes and allows for excellent efficiency and
reproducibility.
Both P-CAP and P-CAP-DP™ are covalently bonded polymer based
chiral stationary phases with high stability, no memory effect, high sample
loadability, and easy scale-up. Selectivity can be obtained in a variety of
solvent choices with different efficiencies. Salt and/or acetic acid can be
added to improve efficiency or enhance detection in mass spectrometry. P-CAP-DP
uses similar protocols as P-CAP and can be optimized for either normal or polar
organic mobile phase. It is less polar than P-CAP, and ideal for sub- and supercritical
fluid applications. The elution order of compounds can be reversed in the (R,R)
versus (S,S) configuration. P-CAP is patent pending, and is manufactured under
license from La Sapienza, Università degli Studi di Roma.
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