Silicene: Wet-Chemical Exfoliation Synthesis and Biodegradable Tumor Nanomedicine.

Silicon-based biomaterials play an indispensable role in biomedical engineering; however, due to the lack of intrinsic functionalities of silicon, the applications of silicon-based nanomaterials are largely limited to only serving as carriers for drug delivery systems. Meanwhile, the intrinsically poor biodegradation nature for silicon-based biomaterials as typical inorganic materials also impedes their further in vivo biomedical use and clinical translation. Herein, by the rational design and wet chemical exfoliation synthesis of the 2D silicene nanosheets, traditional 0D nanoparticulate nanosystems are transformed into 2D material systems, silicene nanosheets (SNSs), which feature an intriguing physiochemical nature for photo-triggered therapeutics and diagnostic imaging and greatly favorable biological effects of biocompatibility and biodegradation. In combination with DFT-based molecular dynamics (MD) calculations, the underlying mechanism of silicene interactions with bio-milieu and its degradation behavior are probed under specific simulated physiological conditions. This work introduces a new form of silicon-based biomaterials with 2D structure featuring biodegradability, biocompatibility, and multifunctionality for theranostic nanomedicine, which is expected to promise high clinical potentials.