E. Van Gyseghem

Determining orthogonal chromatographic systems prior to the development of methods to characterise impurities in drug substances.

To define starting conditions for the development of methods to separate impurities from the active substance and from each other in drugs with an unknown impurity profile, the parallel application of generic orthogonal chromatographic systems could be useful. The possibilities to define orthogonal chromatographic systems were examined by calculation of the correlation coefficients between retention factors k for a set of 68 drugs on 11 systems, by visual evaluation of the selectivity differences, by using principal component analysis, by drawing color maps and evaluating dendrograms. A zirconia-based stationary phase coated with a polybutadiene (PBD) polymer and three silica-based phases (base-deactivated, polar-embedded and monolithic) were used. Besides the stationary phase, the influence of pH and of organic modifier, on the selectivity of a system were evaluated. The dendrograms of hierarchical clusters were found good aids to assess orthogonality of chromatographic systems. The PBD-zirconia phase/methanol/pH 2.5 system is found most orthogonal towards several silica-based systems, e.g. a base-deactivated C16 -amide silica/methanol/pH 2.5 system. The orthogonality was validated using cross-validation, and two other validation sets, i.e. a set of non-ionizable solutes and a mixture of a drug and its impurities.

Development of a generic flow injection analysis method for compounds with a secondary amine or amide function, using an experimental design approach: I. Selection and evaluation of the FIA system parameters

Abstract A second part in the development of a generic flow injection analysis (FIA) method to determine compounds with a secondary amine or amide in their structure is described. This part consists in the selection and evaluation of the chemical reaction conditions. Sodium hypochlorite first converts the secondary amine or the amide to a primary amine. The latter reacts with o-phthalaldehyde (OPA) and a thiol (N-acetylcysteine (NAC)) to form a derivative which can be measured fluorimetrically. To investigate the influence of the different chemical reaction parameters on the peak height for a set of 31 pharmaceutical compounds, a quarter-fraction factorial design for six factors at two levels (26–2-resolution IV, 16 experiments) was executed. Effects on the responses were calculated for each compound. Parallel coordinate geometry (PCG) plots and principal component analysis (PCA) were also applied on the measured responses as aids in the interpretation of the results.

Skills development by project-based education in the food and diet course of a pharmacy program

Project-based education was introduced in the food and diet course of the Masters program in Pharmacy at the Vrije Universiteit Brussel. The students were divided into groups, each dealing with two projects. One was related to general food science and one to diet products available in public pharmacies. For each project the students prepared a report, an oral presentation and a publication (such as a poster, flyer, article or website) oriented to a broad public. The tutor of each group supervised the activities and evaluated the students both individually and as a team. The students also evaluated their fellow group members. Moderate to high correlations were observed between the evaluations of tutors and students. Over the years it has been observed that the introduction of project-based education improves particular skills of students. Individual evaluation was somewhat problematic, but a suitable methodology was attempted.