Conformational structure variation of human serum albumin after binding interaction with black phosphorus quantum dots.

Herein, binding interaction between black phosphorus quantum dots (BPQDs) and human serum albumin (HSA) was systematically characterized for deep illustration of conformational structure variation of HSA affected by BPQDs. The results confirmed that the intrinsic fluorescence of HSA was statically quenched by BPQDs mainly through van der Waals interaction and hydrogen bond. BPQDs bound strongly with the site I of HSA to form ground state complex with molar ratio of 1 to 1. The secondary structure of HSA was changed obviously after its binding interaction with BPQDs, and the α-helix structure of HSA was transformed to the β-sheet structure. The melting temperature of HSA was decreased after its binding interaction with BPQDs, suggesting that BPQDs promoted the thermal denaturation process of HSA. BPQDs could also reduce the molar enthalpy change and the thermal stability of HSA. These results explored the exact conformational structure variation of HSA after its binding interaction with BPQDs, which provides vital information for possible biological influence of BPQDs on human beings.