Compared with micron-sized ultrasound contrast agents, the use of nano-carriers and blood vessels to penetrate into the tissue for imaging and the installation of therapeutic agents in the contrast agent carrier has become one of the current development trends of contrast agents. In
this study, based on the self-assembly characteristics of phospholipid molecules on the surface of free bubbles, lipid-encapsulated nano-bubbles were prepared and optimized. Firstly, sulfur hexafluoride (SF6) type nano-dissolved gas water was prepared based on the dissolved air
pump method, and then it was combined with the dried phospholipids to form the air-containing liposomes (ACL). After the nano ACL was generated, it was undertaken as drug carrier, and Baze was used as a model drug to analyze its inhibitory effect on triple-negative breast cancer cells. Finally,
in the clinical field, ultrasound combined with cancer antigen 125 (CA125) loaded with nano ACL was used for early pathological diagnosis of ovarian epithelial cancer. The test results showed that the distribution peak of the nano-dissolved gas water particles appeared at 140 nm, and the peak
shifted after addition of sodium chloride (NaCl) or bazedoxifene (Baze), proving the existence of free nano-bubbles in the dissolved gas water. The number of layers of nano ACL was 4˜14, and the particle size was 193.8±6.2 nm. Under the conditions of in vitro ultrasound,
both perfusion imaging and aggregation imaging showed strong ultrasound imaging effects. With the addition of drug-loaded ACL and 42.8 kPa ultrasound, the survival rate of MDA-MB-231 breast cancer cells was only 61.28±2.38%, which meant that the drug-loaded nano ACL + ultrasound can
significantly inhibit the cells survival rate (P <0.05). Ultrasound combined with CA125 loaded with nano ACL can greatly improve the early pathological diagnosis rate of epithelial ovarian cancer, and the corresponding positive rate exceeded 90% (P <0.05).