Binding of Tetrabromobisphenol A and S to Human Serum Albumin Is Weakened by Coexisting Nanoplastics and Environmental Kosmotropes

Abstract

Human serum albumin (HSA) was used as a model protein to explore the effects of brominated flame retardant (BFR) binding and the corona formation on polystyrene nanoplastics (PNs). Under physiological conditions, HSA helped to disperse PNs but promoted the formation of aggregates in the presence of tetrabromobisphenol A (TBBPA, ΔD h = 135 nm) and S (TBBPS, ΔD h = 256 nm) at pH 7. At pH 4, these aggregates became larger with fewer electrostatic repulsion effects (ΔD h = 920 and 691 nm for TBBPA and TBBPS, respectively). However, such promotion effects as well as BFR binding are different due to structural differences of tetrabromobisphenol A and S. Environmental kosmotropes efficiently stabilized the structure of HSA and inhibited BFR binding, while the chaotropes favored bioconjugated aggregate formation. Such effects were also verified in natural seawater. The newly gained knowledge may help us anticipate the behavior and fate of plastic particles and small molecular pollutants in both physiological and natural aqueous systems.

Synthesis of hydroxyethyl starch 200/0.5‐loaded albumin nanoparticles: biocompatibility and interaction mechanism

“…The results, listed in Table 1, showed that the K SV values were negatively correlated with temperature. The K q values obtained were higher than 2.0 × 10 10 M −1 s −1 [16], indicating that static quenching was the dominant mechanism of BSA quenching with HES 200/0.5, which was initiated by the formation of a complex [17].…”