Charge-driven corona formation and nanoparticle cellular uptake: A microfluidic study on nanoparticle-protein...

Protein corona (PC) formation on nanodrug carriers compromises drug delivery efficiency. This study examined how nanoparticle surface charge governs PC composition and cellular uptake. Specifically, the negatively charged DPE-PCL nanoparticles (DPNs), and positively charged DPE-PCL-Gly nanoparticles (DPGNs), were used as models and co-injected with serum into microfluidic channels to replicate vascular shear conditions, with static incubation serving as the control. Using techniques such as sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and liquid chromatography tandem mass spectrometry (LC-MS/MS), we characterized the PC in detail. Dynamic conditions amplified charge-dependent heterogeneity in protein adsorption behaviors, including flow rate-correlated adsorption capacity and variations in relative abundance. Shear stress conditions led to broader-spectrum protein adsorption by negatively charged DPNs and reduced protein adsorption by positively charged DPGNs. The preference of nanoparticles for adsorption of representative proteins was evaluated and possible interactions between high-abundance proteins were analyzed using protein molecular docking simulations. Owing to the multilayer structure of PC, the nanoparticle surface charge had a regulatory effect on the inner-layer proteins, indirectly shaping the PC through protein-protein interactions. Although serum-derived PC significantly impeded cellular uptake of nanoparticles, pre-coating with albumin enhanced cellular uptake efficiency. This work provides a source of reference for the design of nanodrug delivery systems.