This study will address the quality of two commercially available medicinal products (Meriofert/Merional and Menopur) as a representative class of medicines containing highly purified human menopausal gonadotropins as biological active pharmaceutical ingredients.

Molecular weight determination, assessment of the purity and structural integrity, including possible aggregation and sequential deglycosylation for glycan monitoring, forced degradation testing will be achieved using 1-D gel electrophoresis under reducing and non-reducing conditions after optimization of gel staining procedures. 2-D gel electrophoresis will be used for the molecular weight and pI determination of glycoisoforms, to assess charge heterogeneity and isoform pattern studies, as well as detailed glycosylation investigations with and without enzymatic release of glycan moieties. N-glycosidase F, sialidase and O-glycosidase will be used to remove N-linked glycans, terminal sialic acids and O-linked glycans, respectively. Reduction of sample complexity for subsequent MALDI-MS analysis will be aspired.

In order to assess the effects of severe storage or transport conditions on the stability of the medical product and to validate the stability of glycoproteins 2-DE will be used to test its suitability. 

For glycoprotein identity confirmation separated proteins will be further subjected to MALDI-TOF-MS analysis after in gel tryptic digestion and peptide extraction. Experimental peptide masses will be compared to peptide masses obtained by in-silico trypsin digestion using different search engines and databases.

A global glycan information will be gathered from MALDI-TOF-MS analyses after enzymatically release of N- and O-glycans. To gain deeper understanding of glycan composition and to dertermine glycosylation sites in detail, oligosaccharide profiling and glycopeptide analyses will be performed by LC-ESI-MS.