基于光动力疗法的四苯基卟啉脂质体制备及体外抗肿瘤活性评价

Preparation and in vitro antitumor activity evaluation of tetraphenylporphyrin liposomes based on photodynamic therapy

目的制备四苯基卟啉脂质体(TPP-Lip)以提高游离四苯基卟啉的水溶性、稳定性和靶向性,同时对该脂质体进行体外抗肿瘤活性评价。方法测定光敏剂四苯基卟啉的单线态氧,采用薄膜分散超声法制备TPP-Lip,并通过细胞摄取和细胞毒性实验考察TPP-Lip光动力疗法对黑色素瘤细胞B_(16)F_(10)和乳腺癌细胞4T1的抗肿瘤活性。结果制备得到形态均匀的球形或类球形脂质体TPP-Lip,其包封率为(88.84±2.64)%,粒径为(115.84±3.89)nm。体外实验考察得到B_(16)F_(10)细胞和4T1细胞最佳光照时间分别为3、6 min,两者的最佳孵育时间均为4 h。设定TPP-Lip浓度梯度为1.25~30μg/mL,在此范围内脂质体对B_(16)F_(10)和4T1细胞有较好的光毒性,IC_(50)值分别为13.73、16.30μg/mL,并对2种细胞的暗毒性均较小。同时,CFPE标记的脂质体在2种细胞中的摄取程度差异不大。结论成功制备出四苯基卟啉脂质体并具有良好的稳定性,TPP-Lip通过光动力疗法发挥体外抗肿瘤作用,为疏水性光敏剂的应用提供参考。

Objective To prepare tetraphenylporphyrin liposomes(TPP-Lip)to improve the water solubility,stability and targeting of free tetraphenylporphyrin,and to evaluate in vitro antitumor activity of the liposomes.Methods The singlet oxygen of the photosensitizer tetraphenylporphyrin was measured,and TPP-Lip was prepared by thin film dispersion ultrasonic method.Then,the in vitro antitumor activity of TPP-Lip photodynamic therapy on melanoma cell B_(16)F_(10) and breast cancer cell 4T1 were investigated by cell uptake and cytotoxicity assay.Results The uniform spherical or spheroid lipsome TPP-Lip was prepared with encapsulation efficiency of(88.84±2.64)%and particle size of(115.84±3.89)nm.In vitro experiments showed that the optimal illumination time for B_(16)F_(10) cells and 4T1 cells was 3,6 min,respectively,and the optimal incubation time of both cells was 4 h.The concentration gradient of TPP-Lip was set at(1.25-30)μg/ml.Within this range,the liposomes showed good phototoxicity to B_(16)F_(10) and 4T1 cells,with IC_(50) values of 13.73 and 16.30μg/ml,respectively.The dark toxicity of the liposomes to B_(16)F_(10) and 4T1 cells was small.At the same time,there was no significant difference in uptake of CFPE labeled liposomes in the two types of cells.Conclusion Tetraphenylporphyrin liposomes with good stability were successfully prepared.TPP-Lip exerted in vitro anti-tumor effects through photodynamic therapy,which may provide a reference for the application of hydrophobic photosensitizers.