Preparation Of Liposomes Loaded Dual Clinical Photosensitizers And Study On Their Photodynamic Induction Of Apoptosis In Human Cervical Cancer Cells

Photodynamic therapy（PDT）has become a promising anticancer strategy with its minimally invasive,low toxicity and repeatability.Objective:To design and synthesize a liposomal nanoparticle Ce6-MB@Lips,which can be excited by near-infrared（NIR）light,and to explore its application as a fluorescent nanoprobe and photosensitizer in NIR fluorescence imaging and photodynamic therapy of cervical cancer cells.Methods:Ce6@Lips,MB@Lips and Ce6-MB@Lips NPs were prepared by a thin film dispersion method and characterized for their morphology,particle size,polydispersity index（PDI）,stability,encapsulation rate,drug loading rate and release rate at different p H;a 660 nm laser and an ABDA indicator were used to evaluate Ce6,MB,Ce6@Lips,MB@Lips and Ce6-MB@Lips to produce singlet oxygen（¹O₂）;the dark toxicity of Ce6,MB,Ce6@Lips,MB@Lips and Ce6-MB@Lips on cervical normal and tumor cells and their mediated phototoxicity of PDT on cells were detected by the CCK8 method;and the confocal fluorescence imaging system was used to assess the cellular toxicity of Ce6,MB,Ce6@Lips,MB@Lips and Ce6-MB@Lips uptake in tumor cells and the ability of fluorescent labeling;qualitative and quantitative detection and comparison of reactive oxygen species production in tumor cells by confocal fluorescence imaging system and flow cytometry;evaluation of the prepared nanoparticles-mediated PDT-induced apoptosis in tumor cells by Annexin-V-FITC/PI apoptosis assay.The ability of the prepared nanoparticles to induce apoptosis in tumor cells was evaluated by Annexin-V-FITC/PI apoptosis assay.Results:Ce6-MB@Lips was a monodisperse spherical nanostructure with an average particle size of 160.3 nm.Ce6-MB@Lips had two characteristic absorption peaks at 413 nm/670 nm and a fluorescence peak at 697 nm.Compared with Ce6,MB,Ce6@Lips and MB@Lips,Ce6-MB@Lips exhibited better stability,stronger fluorescence intensity and higher ¹O₂ production capacity.The results of cellular experiments showed that after effective cellular internalization,Ce6-MB@Lips exhibited low cytotoxicity,high phototoxicity and excellent ROS generation ability,thus prompting more apoptosis of tumor cells in vitro.Conclusion:The successfully synthesized Ce6-MB@Lips NPs,as a novel fluorescent nanoprobe and photosensitizer,had great water solubility,low toxicity,excellent fluorescent labeling cell ability and ROS generation ability,and had a stronger killing effect on cervical tumor cells under NIR laser stimulation,thus Ce6-MB@Lips is expected to bring a new dawn to the diagnosis treatment of cervical cancer.