Functionalization dependent biodegradability of two-dimensional antimonene by peroxidases: impact on immune modulation

Antimonene (Sb) is an emerging two-dimensional material belonging to group VA that has shown excellent chemical and physical properties with applications in optoelectronics, energy, catalysis, and biomedical sciences. However, the biodegradability of Sb sheets in response to immune stimulation and its impact on degradation by-products have yet to be reported. Herein, we investigated the biodegradability of Sb nanosheets by treating them with human myeloperoxidase (hMPO) and plant peroxidase (horseradish peroxidase-HRP) in the presence of a low concentration of hydrogen peroxide. Furthermore, we studied the impact of non-covalently functionalized Sb nanosheets with 2-hydroxypropyl-β-cyclodextrin (Sb-CD) on their biodegradability. The biodegradability of Sb sheets was assessed using Raman spectroscopy, UV-vis spectroscopy and transmission electron microscopy. The results revealed that functionalized Sb sheets exhibited reduced degradability upon treatment with peroxidase due to the surface coating of β-CDs on Sb sheets. Next, the cytotoxicity results revealed that the pristine and functionalized Sb sheets and their by-degradation products did not affect human THP1 cells. Finally, the immune modulation studies with THP1 cells confirmed that Sb-nanosheets before and after partial degradation did not show significant production of TNF-α, confirming that Sb-nanosheets or degraded products played no role in the activation of the immune response. These results could provide better insights into the biodegradability of Sb sheets and their potential biomedical applications.