ABSTRACT
Zeptoproteomics is the term that has been coined to defi ne proteomic technology optimized to analyze protein expression in a limited number of cells (6). The preimplantation embryonic stage represents the most diffi cult challenge for zeptoproteomics with the combined effect of limited numbers of cells and minimal protein expression, resulting in extremely low levels of total protein available for analysis, only 27 ng of protein in a single mouse embryo (7).
