Protein corona of metal-organic framework nanoparticals: Study on the adsorption behavior of protein and cell interaction

Nanoscale metal-organic frameworks (NMOFs) have attracted considerable attention for controlled drug delivery. However, the interaction between nanoparticles and the biological macromolecules of physiological system must be valued because the formed protein corona will endow NMOFs with new biorecognition properties. In this study, we carried out detailed protein adsorption studies in vitro and cell uptake tests of HeLa cells for nanospherical Uio66 and nanooctahedral Uio67. Uio67 with higher binding constants to human serum albumin needed to combine more protein molecules to achieve colloidal stability state than that needed by Uio66, and this phenomenon led Uio67 to aggregate under the same incubation condition due to the formation of a single-layer protein. Uio67 also induced an evident conformation change in protein to stabilize the combination. In particular, the cell uptake efficiencies of the two systems showed a significant thickness dependence on the protein corona. When samples incubated in 10% fetal bovine serum (FBS), the intracellular rate was the highest for both systems, but the rate was not proportional to the FBS concentration. Results of this work are important to the development of the considerable potential NMOFs-based medicals and also provide additional insight into protein corona.