Degassers mitigated bubbles from upstream flow through microfluidic chips, with minimal absorption or leaching. (A) Photos of chips after media was perfused overnight (1 µm/min, 20 h, 37 °C) with or without in-line bubble traps (n = 3 chips), with the fraction of chips that contained no bubbles (“run success”) noted below. The X’s and squares in the left image are alignment markers that were included in some of the chips. (B) Plot of fluorescent signal from absorption of rhodamine into bubble trap materials before and after 24-h exposure. Two-way ANOVA, ** p < 0.0093, * p = 0.0377, ns > 0.9998, n = 3. (C) UV-Vis absorbance (A280) of AIM-V media after overnight perfusion through the traps, compared to non-conditioned media. One-way ANOVA, ns > 0.2297. Points indicate individual samples, bars show the mean and standard deviation.