The macromolecular organic material explored in this work, namely, LPS, laminarin, and BCL, readily aggregate into inclusions in the aerosol center and are stabilized by FA clusters. This finding supports the coreshell morphology to a limited extent; in addition to saturating the surface, organics, and specifically BCL, also accumulate in the center of the particle. Mael et al. recently observed this phenomenon during water uptake experiments: neither complete phase separation nor full dissolution occurs in the case of some organics, leading to the formation of inclusions. 121 Additionally, Huang et al. observed that organic aerosols with an organic component containing an O:C ratio < 0.8 exhibited phase coexistence. The O:C ratios of our SSA models align well with this observation (Table ).