Rapid Formation of Size-controlled 3-dimensional Hetero-spheroid Using Micro-rotational Flow

In this paper, we demonstrate formation of size-controlled 3-dimensional hetero-spheroids using a micro-fluidic device in approximately 2 min. The device collects cells in the center of a micro-chamber using micro-rotational flow as shown in Fig. 1. In previous work, we used this device to generate size-controlled HepG2 spheroids [1]. We applied it to form heterospheroids consisting of HepG2 and HUVEC. We experimentally found that the spheroid sizes could be controlled by the cell densities of the media independent of the ratio of HepG2 and HUVEC. Uniform dispersion of HepG2 and HUVEC in the formed spheroid was also experimentally verified.