Factorial design approach for optimisation of high performance liquid chromatographic conditions of tropane alkaloids determination

The determination of tropane alkaloids such as hyoscyamine and scopolamine in plant samples requires the choice of optimal high performance liquid chr omatography (HPLC) conditions for receiving a good separation of these comp ounds and narrow peaks for reliable integration. The influence of four fact ors on the retention time of these compounds and their corresponding chroma tographic separation was investigated using a factorial design approach. Th e evaluation of the results allowed for a ranking of the factors according to the strength of their impact. Furthermore, interactions between the fact ors under investigation in respect to the retention time and the separation were examined and a desirability function was established combining both r esponses. Using the results of the factorial design, optimised conditions f or the high performance liquid chromatographic (HPLC) method could be set. The study showed the efficiency of the factorial design approach to reach o ptimised conditions while the number of required trials is minimised as dem onstrated by analysing the main alkaloids (hyoscyamine and scopolamine) fro m Datura stramonium seed samples.