Biointerface Behavior of Layered Double Hydroxides: Dispersibility and Toxicity Assessment Using Experimental and...

Layered double hydroxide (LDH) nanosheets are widely explored for applications in pharmaceutics, catalysis, environmental remediation, energy generation, and chemical sensing. With their ever-expanding applications, it is essential to comprehensively understand their interactions at biological and environmental interfaces to ensure both safety and sustainability. The study reports the synthesis and characterization of Mg-Al LDH, followed by a systematic evaluation of their dispersibility, environmental stability, and biological interactions using integrated experimental and computational approaches. Stable dispersions were observed in biologically and environmentally relevant media, including BSA, DMSO, RPMI with FBS, and Type I water, for up to 72 h. Cellular uptake studies in HepG2 cells demonstrated both dose- and time-dependent internalization of Mg and Al. Exposure to LDH for 48 h induced a significant (**: p ≤ 0.01), dose-dependent reduction in cell viability in HepG2 (at 250 mg/L to 1000 mg/L) and in HL60 cells (at 1000 mg/L). No significant alterations in reactive oxygen species (ROS) generation (500 mg/L to 10 ng/L) and no significant DNA damage were observed in HepG2 cells at concentrations of 10 μg/L and 10 ng/L. Flow cytometric apoptosis and mitochondrial permeability assays revealed a marked loss of mitochondrial permeability and alteration of cellular morphology at higher concentrations (250 mg/L, 500 mg/L) without inducing apoptosis. However, at environmentally relevant concentrations (ng-μg/L), no significant changes were detected in mitochondrial membrane potential, cellular morphology, and cell cycle progression, indicating concentration-dependent biosafety. Computational docking indicated predominantly weak interactions between LDH nanosheets and 21 apoptotic signaling proteins. The study highlights that the dispersion behavior and intrinsic properties of Mg-Al LDH nanosheets contribute to their low-hazard biological profile, supporting their safe use in applications. To the best of our knowledge, this is the first study to systematically investigate the biointerface behavior of Mg-Al LDH nanosheets, combined with a computational model.