Fig. 1
Schematic illustration of the preparation of MBVEGFR2 and MBVEGFR2-based molecular ultrasound imaging for earlier detection of microinvasive cervical cancer in vivo. (A) Synthesis of MBVEGFR2. (B) Molecular ultrasound imaging of microinvasive cervical cancer via MBVEGFR2. After cervical cancer modeling in mice, MBVEGFR2 suspension was injected into the tail vein. Based on the clinical ultrasound imaging system, the high frequency linear probe was used to achieve the VEGFR2-targeted molecular ultrasound imaging by means of destructive replenishment. The contrast signals of the adherent microbubbles and circulating microbubbles were continuously captured for 30 s. Then all the microbubbles were destroyed using a destructive pulse with a high mechanical index for 1 s. Ultrasound imaging was performed for 10 s to obtain the signal of freely circulating microbubbles after destruction. Thus, the quantification of targeted signals was calculated by the difference between the signal intensity before and after destruction, which was represented as the normalized intensity difference (NID). Perfluoropropane gas, C3F8; Vascular endothelial growth factor receptor type 2 (VEGFR2) targeted microbubble, MBVEGFR2;