Figure 7.

(A) Schematic illustration of drug-loaded and echogenic chitosan-based nanoparticles (Echo-CNPs). Size distribution (B) and TEM images (C) of Echo-CNPs compared with CNPs, Sonovue^®, and PFP-GC. (D) In vivo biodistribution of fluorescent FlammaTM labeled Echo-CNPs after 1 h, 3 h, 24 h, and 48 h post-tail vein injection with or without US irradiation. (E) Fluorescent intensities on the target tumor tissue after 1 h and 3 h post-injection with or without US treatment. (F) In vitro fluorescence imaging of the excised tumor tissues with or without US treatment. (G) Real-time dynamic drug release process visualized by OV-100 micro-vessel imaging system in tumor tissue after 10 min tail vein injection, and subsequently exposed to US destruction mode for 5 min. Adapted from Min HS, You DG, Son S, et al. Echogenic Glycol Chitosan Nanoparticles for Ultrasound-Triggered Cancer Theranostics. Theranostics. 2015;5(12):1402–1418. Copyright 2015 Ivyspring International Publisher (https://creativecommons.org/licenses/by-nc/4.0/legalcode).⁶⁴