Abstract Multicellular tumor spheroids embedded in collagen I matrices are common in vitro systems for the study of solid tumors that reflect the physiological environment and complexities of the in vivo environment. While collagen I environments are physiologically relevant and permissive of cell invasion. studying spheroids in such hydrogels presents challenges to key analytical ass... https://www.spidertattooz.com/The-GelBottle-Inc-BIAB-Gel-Polish-Spirited-67oz-p17706/