Preparative agarose gel electrophoresis for reducing matrix interferences of organoid cell medium prior to LC-MS analysis of insulin

Organoids are 3D cell cultures with microanatomies mimicking aspects of real organs, useful for e.g. animal -free studies of development, disease, and drug discovery. The cell medium of organoid models of Langerhans islets, regulating blood glucose levels by insulin secretion, can be analyzed by liquid chromatography -mass spectrometry (LC -MS). However, organoid medium complexity is a major challenge, as matrix interferences can reduce sensitivity and selectivity, even with optimized LC -MS conditions. By applying preparative agarose gel electrophoresis-electrodialysis (PGE-ED), we were able to decrease the cell medium background signal, allowing for reduced interferences affecting LC -MS analysis of human insulin.