目的:研制一种乳腺癌细胞膜(CCM)包被的载血卟啉单甲醚(HMME)仿生纳米分子探针，观察其体外靶向同源乳腺癌细胞的能力，并探讨其体外增强光声显像及声动力治疗(SDT)乳腺癌的效果。方法:通过化学裂解及反复冻融法提取乳腺癌4T1细胞膜，然后以双乳化法联合挤压法制备CCM包被的载HMME的聚乳酸-羟基乙酸共聚物仿生纳米粒作为分子探针(CHP-NPs)。检测纳米粒的基本表征；体外观察纳米粒对同源乳腺癌细胞的靶向能力及增强光声显像的效果；以单线态氧荧光探针(SOSG)验证纳米粒产生活性氧(ROS)的性能，并以CCK8细胞毒性实验评估其对乳腺癌细胞的SDT效果。结果:所制备的CHP-NPs大小均一，形态规则呈球形“核壳结构”，粒径为(275.23±8.25)nm，表面电位为(-18.43±0.45)mV;激光共聚焦显微镜下观察到CHP-NPs能靶向同源4T1细胞；体外光声显像实验显示，纳米粒光声信号随其浓度的升高而增强；经SOSG探针检测，CHP-NPs在超声辐照下可产生ROS；单独CHP-NPs与4T1细胞共同孵育，不应用超声辐照时，对细胞存活率无明显影响，其浓度为0.6 mg/ml时细胞存活率仍达95%；经超声辐照时，CCK8实验显示该CHP-NPs对乳腺癌细胞具有显著的SDT效果。结论:成功制备出乳腺癌细胞膜仿生纳米分子探针，该探针具有良好的靶向同源肿瘤的能力，并可显著增强肿瘤光声显像及SDT效果。“,”Objective:To develop a biomimetic nanoparticle probe of hematoporphyrin monomethyl ether (HMME) coated with breast cancer cell membrane, to observe its ability to target homologous breast cancer cells in vitro, and to investigate its effect of enhanced photoacoustic imaging and sonodynamic therapy (SDT) for breast cancer in vitro.Methods:The cell membrane of breast cancer 4T1 was extracted by chemical cleavage and repeated freezing and thawing. Then the HMME-coated polylactic acid-glycolic acid copolymer biomimetic nanoparticle was prepared by double emulsification and extrusion. The basic characteristics of nanoparticles were detected. The target ability of nanoparticles to homologous breast cancer cells and the enhancement of photoacoustic imaging were observed in vitro. Singlet oxygen sensor green (SOSG) was used to verify the reactive oxygen species (ROS) production of nanoparticles, and its SDT effect on breast cancer cells was evaluated by CCK8 cytotoxicity assay.Results:The size of the prepared CHP-NPs was uniform, the morphology was spherical “core-shell structure” , the particle size was (275.23±8.25)nm, and the surface potential was (-18.43±0.45)mV. It was observed that CHP-NPs could target homologous 4T1 cells under laser confocal microscopy. In vitro photoacoustic imaging experiments show that the photoacoustic signal of nanoparticles increases with the increase of its concentration. According to SOSG probe detection, CHP-NPs could produce ROS under ultrasonic irradiation.When CHP-NPs was incubated with 4T1 cells alone and no ultrasonic irradiation was used, the cell survival rate was not significantly affected. When the concentration was 0.6 mg/ml, the cell survival rate was still 95%. After ultrasonic irradiation, CCK8 experiment showed that the CHP-NPs had a significant SDT effect on breast cancer cells.Conclusions:The biomimetic nanomolecular probe of breast cancer cell membrane is successfully prepared. The probe has good ability to target homologous tumor, and can significantly enhance tumor photoacoustic imaging and SDT effect.