In situ Analysis of Nanoparticle Soft Corona and Dynamic Evolution

How soft corona i.e., the protein corona’s outer layer contributes to “biological” identity of nanomaterials (NMs) is largely unknown due to a longstanding challenge in capturing protein composition of the soft corona in situ. We herein develop an in situ “Fishing” method that can monitor the dynamic formation of protein corona on ultra-small chiral Cu2S nanoparticles (NPs) allowing us to directly separate and identify their protein composition. This method can detect spatiotemporal processes in the evolution of hard and soft coronas on chiral NPs, revealing subtle differences in their composition even within several minutes. This study highlights the importance of in situ and dynamic analysis of soft/hard corona composition, provides detailed insights into the roles of protein corona composition in mediating the biological responses of NPs, and offers a universal strategy to characterize the soft corona that will serve as a powerful tool for rational design of biomedical NMs.