Retention Behaviour of Selected Alkaloids on Bonded Stationary Phases by HPLC

Abstract

Retention of selected alkaloids on polar bonded stationary phases such as diol‐, NH₂‐silica in normal‐phase systems and diol‐, CN‐silica in reversed phase systems is determined by use of HPLC. Mixtures of 2‐propanol and n‐heptane are used as non‐aqueous eluents; aqueous buffered (at pH about 8) solutions of methanol or acetonitrile were used in RP systems. Obtained results are presented graphically as retention—eluent composition relationships, as log k vs. log k correlation diagrams, and by chromatographic spectrum. The selectivity of separation in NP and RP systems has been discussed. In RP systems, retention on diol and CN‐phases is compared with the results obtained on C18 and silica phases. The most selective systems for the separation of particular groups of alkaloids are chosen.

Keywords:

• Polar bonded stationary phases
• Alkaloids
• Selectivity
• RP systems
• NP systems
• HPLC
• Retention behaviour