Comparison of cytotoxicity of black phosphorus nanosheets in different types of fibroblasts

Two-dimensional black phosphorus nanosheets (BPNSs) have recently emerged as a successive novel nanomaterial owing to their uniqueness in optical and electrical properties. Although BPNSs have found a wide range of biomedical applications, their biosafety is still a major concern to be addressed.In this study, we have prepared layered BPNSs using liquid exfoliation procedure, and evaluated their physicochemical properties using Fourier Transform-infrared (FTIR) spectroscopy, Raman spectroscopy, atomic force microscopy, and Zetasizer analyses. We have investigated potential cytotoxicity of BPNSs against three different types of fibroblast cells, i.e. mouse embryonic fibroblast (NIH3T3), primary cultured normal human dermal fibroblast (nHDF), and fibrosarcoma (HT1080). Cell counting kit-8 (CCK-8) assay was carried out to assess cellular metabolic activity in cells whereas lactate dehydrogenase (LDH) activity assay was helpful to study plasma membrane integrity.Our salient research findings showed that BPNSs were polydispersed in solution due to aggregation. Toxic response of BPNSs against fibroblast cells was in the order, HT1080>nHDF>NIH3T3. The nanosheets reduced the number of cancerous cells with significant difference to normal cells.We suggest that BPNSs can be considered for cancer treatment as they destroy cancerous cells effectively. However, a comprehensive study is required to elucidate other biological effects of BPNSs.