Potentiated cytosolic drug delivery and photonic hyperthermia by 2D free-standing silicene nanosheets for tumor nanomedicine

Abstract

Silicene, as an emerging two-dimensional (2D) silicon allotrope, mainly serves in the field of electronics and energy devices but multidisciplinary studies on 2D silicene have been rarely carried out, especially the potential translational biomedical practice. In this study, we explore a high-performance photonic drug-delivery nanoplatform based on 2D ultrathin silicene nanosheets (DOX@silicene-BSA NSs) regarding effective chemotherapeutic drug loading (capacity amount of w/w%: 137.0%) while highlighting the potentiated cytosolic drug-delivery efficiency (spatiotemporally pH-/NIR-triggered drug-release) and NIR-II-activated photonic hyperthermia (η = 19.7%) performance, thus, enabling the potential synergistic chemotherapeutic and phototherapeutic outcomes. The cellular endocytotic mechanism of these nanosheets in cancer cells has been comprehensively studied and provides an essential understanding of the nano-bio interactions of silicene-based nanosheets or other emerging 2D nanostructures. Prominent suppression of tumor growth was achieved by synergistic chemotherapy and photonic hyperthermia with negligible adverse effects and expected degradability, thus addressing the several fundamental barriers of oncology-related nanotherapies. This work highlights silicene, which integrates the merits of high specific surface area endowed with 2D topology, intrinsic responsiveness toward physical/chemical stimuli, and biomedical necessity of biodegradation and biosafety, as a promising next-generation omnipotent alternative to subrogate traditional silicon-based biomaterials and non-biocompatible nanoagents in clinical translation nanomedicine.