Synthesis Of Multifunctional Nanomaterial Based On Polydopamine And Applications In Cancer Theranostics

Polydopamine?PDA?have been widely used as building blocks for the construction of multifunctional nanoplatforms for various biomedical applications.Moreover,PDA is also a photothermal reagent with outstanding photothermal conversion capability.Photothermal therapy?PTT?is an emerging method for the treatment of the tumor site by converting light energy to heat using photothermal transduction agents.Under near-infrared light?NIR?laser irradiation?808 nm?,PDA converts energy to heat to increase the temperature in the tumor area and kill the cancer cells.However,the widespread clinical use of PTT is still limited mainly due to the lack of tumor-specific energy absorption and diffuse heating.Therefore,it was important to combine PTT with other therapies to improve cancer therapy.The combination of PTT and chemotherapy was an encouraging approach that will lead to better synergistic effects and lower side effects than photothermal therapy or chemotherapy alone.In this thesis,two kinds of multifunctional photothermal nanoparticles were synthesized using PDA as photothermal agents.At present,we developed bowl copper sulfide@PDA nanoparticles?CuS@PDA NPs?,the obtained NPs can be loaded with a large number of anticancer drugs doxorubicin?DOX?due to their special spatial structure,and they have the property of pH/NIR dual-responsive drug release.The resultant CuS@PDA NPs possess excellent biocompatibility,a competent drug loading capability,high photothermal conversion efficiency,which can achieve the purpose of cancer treatment through chemo-photothermal therapy.In the following work,we reported the PDA@upconversion nanoparticle@mesoporous silica yolk-shell nanoparticles?PDA@UCNP@mSiO₂ NPs?to simultaneously load the hydrophilic doxorubicin?DOX?and hydrophobic hydroxycamptothec?HCPT?in their distinct domains without interaction.The oleic acid-coated UCNPs exhibited the multi-mode upconversion luminescence?UCL?/computed tomography?CT?/magnetic resonance?MR?imaging and the hydrophobic environment held great ability for storage of the hydrophobic HCPT.While the mSiO2 shell was used for loading the hydrophilic DOX and ensuring the good water dispersibility of the NPs.In a word,the resulted NPs were successfully employed for multi-mode imaging-guided synergistic dual drug chemo-photothermal therapy of hepatocellular carcinoma.