Although immune system plays a protective role in defensing against infected microbial pathogens in the body, it is also responsible for the clearance of nanomaterials from the circulation. The high level of accumulated nanomaterials may lead to series side effects. Some nanomaterials display several adverse effects upon injected into mice, which could then damage normal tissues. Black phosphorus nanosheets (BPs) are layered semiconductor that consists of corrugated planes of phosphorus atoms with strong intralayer bonding and weak interlayer interactions. Few-layer BPs has a thickness-tunable bandgap, As the promising characteristics, BPs is becoming a powerful agent for various biomedical applications. However, their biocompatibility warrants a detailed evaluation of the safety for BPs use. In the current study, we investigated the toxicity of BPs. Biological effects of BPs with and without titanium sulfonate ligand (TiL4) modification are investigated. We firstly evaluated the cytotoxicity of BPs using macrophages as cell model. We found BPs displayed high potential to be engulfed by macrophages. The intracellular BPs triggered significant cell death. Comparing with control cells, BPs exposure also resulted in the induction of various pro-inflammatory cytokines. In contrast, In vitro experiments suggest that TiL4 modification can reduce the uptake by macrophages, and further attenuate the cytotoxicity and proinflammation. In vivo study demonstrated the adverse effects of BPs on mouse model that peripheral neutrophils and a group of inflammatory cytokines were evaluated. While TiL4@BPs exhibit no such adverse immune responses. We also investigated the mechanisms of the BPs’ inflammatory effects and the improved biocompatibility caused by the TiL4 modification. Our results suggested that more side effects of BPs needed to be evaluated in detail when applied in therapeutics, which can guide their applications as foreign particles administered to animals or humans in the future.

Toxicity of black phosphorus nanosheets (BPs)

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.