4.4.6 Antibacterial ability assay of THB@ANVs
The bacteria imaging was carried by mixing 90 μL of bacteria with 10 μL newly prepared THB@ANVs for 20 min at ambient temperature, then observed on glass slides. The images were collected under FL microscope (100×, excitation filter 528-553nm, dichroic mirror 565nm, emission filter 578-663nm). Scanning electron microscopy (SEM) was applied to observe the morphologies of the bacteria before and after treated with THB@ANVs. After the treatment above, the bacteria were fixed with 2% glutaraldehyde at 4 °C overnight and then rinsed with water, followed by dehydration with a sequential ethanol/water mixtures with an increasing ethanol volume of 30%, 50%, 70%, 80%, 90%, 95%, and 100%, respectively. Finally, the samples were dropped on a silicon wafer, vacuum dried, and coated with platinum before observation.