How Anisotropic Surface Chemistry Changes The Nano-Biomembrane Interaction: From Janus Nanoparticles to Viruses

The non-uniform surface chemistry is ubiquitous for both naturally occurring and engineered nanoparticles. Microbes, such as viruses, are known to have anisotropic presentation of proteins on their surfaces. Engineered nanoparticles are often designed to have heterogeneous surface chemistries to enable novel applications. How does the anisotropic chemistry of nanoparticles impact their interactions with biological membranes and cells? More importantly, can we take advantage of the anisotropic surface chemistry to reverse-engineer nano-bio interactions? In this talk, I will present my group’s recent research progress toward addressing those questions. On the one hand, using engineered “two-faced” Janus nanoparticles with different surface chemistries on two hemispheres, we demonstrated that spatially separating charges and hydrophobicity on the nanoparticles renders them more potent in perforating lipid membranes and thereby in killing a broad range of bacteria. On the other hand, using non-enveloped viruses, we found that the partial hydrophobicity on the viral capsid enables the viruses to deform and penetrate the lipid membrane, leading to their infection of host cells. Our studies from both living and non-living worlds provide direct evidence that the spatial distribution of surface functionalities, rather than just its overall surface chemistry, on a nanoparticle, plays a crucial role in determining its interaction with biomembranes.