Protein corona components of polyethylene glycol-conjugated organosilica nanoparticles modulates macrophage uptake.

Fluorescent organosilica nanoparticles (FNP) conjugated with polyethylene glycol (PEG) of variant molecular weight (2 K, 12 K, 20 K, and 30 K) were prepared to investigate their cellular uptake by murine-derived macrophages. In a medium with FBS, the cellular uptake of FNP-PEGs was decreased as compared to a medium without FBS, indicating that protein corona on FNP-PEGs reduced cellular uptake. Bovine serum albumin (BSA) and hemoglobin (Hb) were detected as the most abundant components on all FNP-PEGs. Pre-coating of FNP-PEGs with BSA and Hb reduced the macrophage uptake in a medium without FBS, suggesting that these components might strengthen the stealth function of PEGs. Furthermore, there was more reduction in uptake of BSA- and Hb-coated FNP-PEGs from a medium with FBS than without FBS. BSA and Hb could be the stealth enhancement protein of FNP-PEGs in vitro.