Figure 2.

In vitro characterization, hypoxia reprogramming, and imaging of nanobubbles. (a) TEM image of nanobubble with an oxygen compartment at the core surrounded by sodium carboxymethylcellulose shell. Scale bar = 50 nm. (b) Dynamic light scattering (DLS) size distribution of nanobubbles. (c) Ultrasound images of the corresponding signal generated from varying concentrations of nanobubbles (0–300 µg/mL). The contrast generated is due to oxygen trapped inside nanobubbles. Scale bar = 1 mm. (d) Graph displaying averaged mean grey scale intensity corresponding to increasing concentrations of nanobubbles (0–300 µg/mL). The results are mean values from three independent experiments. Error bars represent ± s.d. Note that there is a significant linear relationship between mean ultrasound gray scale intensity and concentration of nanobubbles (see Supplementary Fig. 1).