Conjugated Polymer-based Optical Platform For Biological Sensing And Tumor Theranostics

In recent years,due to its excellent optical properties,conjugated polymer materials have shown great prospects in the fields of chemistry,medicine and biological science,which have been paid more and more attention by researchers.The conjugated polymer nanoparticles prepared by co deposition have good solubility in water,biocompatibility and low cytotoxicity.They can be used to construct multi-functional nano platforms with recent popular phototherapy and biosensing.Multi-functional nanoplatforms based on conjugated polymers have been widely used in vitro and in vivo fluorescence imaging to realize real-time cancer diagnosis and treatment in clinical medicine.As a new fluorescent material,water-soluble conjugated polymer has many advantages,such as large molar absorptivity,high fluorescence quantum yield,and soluble in water.It is widely used in the detection of metal ions,small molecules,DNA,RNA,protein and so on.Therefore,the research work in this paper includes 3 aspects.(1)The construction of nano-platform based on photothermal thermo-photodynamic co-treatment and biosensing of conjugated polymers Co-polymers PSBTBT NPs with photothermal therapeutic ability were prepared by co-sedimentation and microemulsion polymerization,and photothermal thermo-photodynamic co-treatment and biosensing were prepared by covalently bonding photosensitizer Chlorin e6 and fluorescent dye Rhod.The conjugated polymer multi-functional nanoplatform uses transmission electron microscopy to characterize the size and morphology of the nanoparticles;the dynamic light scattering instrument characterizes the particle size distribution of the nanoparticles;the UV and fluorescence spectra of the nanoparticles The photophysical properties were characterized.(2)Research on the application of conjugated polymer photothermal photodynamic therapy and biosensing nano-platform The conjugated polymer photothermal photodynamic therapy and biosensing nanoplatform(PSBTBT-Ce6@Rhod)can be used for ratiometric PLD detection and near-infrared light-induced photodynamic and photothermal synergistic treatment of cancer cells.The ability to raise the temperature of the nanoplatform and the ability to generate singlet oxygen were measured under 635 nm laser irradiation;the sensitivity and specificity of the ratio PLD detection using a fluorescence spectrometer was investigated;and the nanometer was examined using the MTT method and the confocal microscope.The ability of the platform to accurately diagnose and treat cancer cells was characterized.(3)A highly sensitive target DNA biosensor was developed on the basis of the cationic water soluble conjugated polymer and the amplification reaction of the enzyme cut cycle signal and the mechanism of fluorescence resonance energy transfer.At the same time,the specific identification ability of the biosensor was studied by using the single base mismatched DNA and other interfering substances.The experimental results showed that the biosensor based on the amplification mechanism of PFEPN+ and Exo ? enzyme cutting cycle signal has high sensitivity and specificity,and the rapid,simple and sensitive detection of target DNA was realized.