Figure 1. Design of experimental protocol optimization for exosome isolation and preparation of secretomes of the colorectal adenocarcinoma cell culture Caco-2 from conditioned medium for subsequent MS analysis. A) isolation of exosomes from conditioned medium according to the UC1-UC2-SUC scheme: Caco-2 cells were cultured in a medium supplemented with PBS (wFBS media), UC1 and UC2 ¬ the first and second ultracentrifugation cycles; SUC - ultracentrifugation using a sucrose cushion; In-solution digestion - hydrolysis in solution; B) Isolation of exosomes and secretome from one initial volume of conditioned medium according to the UF-UCSUC scheme: Caco-2 cells were cultured in the medium with (wFBS media) and without PBS (w/oFBS media), and UF - ultrafiltration with 100 kDa and 5 kDa cut-off, UC - ultracentrifugation, SUC - ultracentrifugation using the sucrose cushion; In-gel Digestion - hydrolysis in gel; FASP - hydrolysis on centrifugal filters.