Proliferative effects of nanobubbles on fibroblasts

In recent years, the potential of nanobubbles (NBs) for biological activation has been actively investigated. In this study, we investigated the proliferative effects of nitrogen NBs (N-NBs) on fibroblast cells using cell assays with image analysis and flow cytometry. A high concentration of N-NBs (more than 4 × 10(8) NBs/mL) was generated in Dulbecco’s modified Eagle’s medium (DMEM) using a gas–liquid mixing method. In image analysis, the cells were counted and compared, which showed an 11% increase in cell number in the culture medium with N-NBs. However, in two further cell cytometry analyses, the effect of nanobubbles on cell division was found to be insignificant (approximately 2%); as there is insufficient evidence that N-NB is involved in cell division mechanism, further studies are needed to determine whether NB affects other cellular mechanisms such as apoptosis. This study presents the first successful attempt of directly generating and quantifying N-NBs in a culture medium for cell culture. The findings suggest that the N-NBs in the culture medium can potentially facilitate cell proliferation. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13534-022-00242-y.