In 2008 Mark started his 1st master-internship medical biology at our department where he investigated the interaction of the TRPV5 calcium channel and CB28k calcium binding protein, two major players involved in renal calcium transport. Interested in renal ion transport, his 1st master thesis dissected the distribution of potassium transporters in the distal convoluted tubule of the nephron. In 2009 he performed a 2nd master-internship at MSD (Organon N.V.) Biological Sterile Product Deveopment. He was crucially involved in the characterization of the oligomerization behavior of a biomolecule and he also developed of a parental drug product formulation of this biomolecule for human. Triggered by pharmacologic research, his 2nd master-thesis established a comprehensive model for cellular internalization of cell penetrating peptides which are potent vectors for drug deliverance. After his successful graduation in medical biology, in Nijmegen in 2010, he recently rejoined our lab and started his PhD trajectory. His project aims to clarify the occurrence of hypomagnesemia in patients which are dependent on the daily intake of proton pump inhibiting drugs.