Preparation Of Polydopamine-based Janus Nanomaterials And Application Analysis In Cancer Treanostics

Cancer is one of the main causes of human death in the world.Therefore,the treatment of cancer has always been highly valued by mankind.Currently,methods of treating cancer include surgical resection,radiation therapy and chemotherapy.However,traditional therapies have certain limitations and serious side effects.Photothermal therapy（PTT）is a cancer treatment technology developed in recent years.It mainly uses photothermal agents to convert absorbed the near-infrared（NIR）light energy into a lot of heat energy,which increases the local temperature of the tumor site to kill cancer cells and reduce systemic toxicity.However,the single PTT has certain limitations.For instance,insufficient laser transmission depth leads to eliminate incompletely at local tumor cells.In order to further achieve the ideal therapeutic effect,chemo-photothermal combined therapy has become a potential cancer treatment.Therefore,it is necessary to explore new multifunctional photothermal nanomaterials for chemo-photothermal combined therapy.Polydopamine（PDA）possesses a unique adhesion,excellent biocompatibility,gentle synthesis requirements,competent drug loading capacity and strong photothermal conversion capability,which has been widely used as drug carriers and photothermal conversion agents.In recent years,multifunctional inorganic/polymer Janus nanoparticles（JNPs）have shown unique properties and attractive biomedical applications because of asymmetry surface and morphology.In this thesis,we explore application of novel multifunctional photothermal JNPs based on PDA in cancer diagnosis and treatment.The specific research contents are as follows:（1）Polydopamine/polyacrylicacid-mesoporouscopperhydroxideJNPs（PDA/PAA-Cu（OH）₂JNPs）were prepared by a novel and simple method for the first time.Here,the side of PDA possesses strong NIR absorbance,excellent biocompatibility and degradability.The other side of PAA-Cu（OH）₂NPs was composed of polyacrylic acid（PAA）nanosphere coordinating copper ions(Cu²⁺),which possesses mesoporous structures for loading anticancer drugs.Besides,Cu（OH）₂achieves organic integration of different functions and synergy effects because it has strong NIR absorption to apply for photothermal therapy.The synthesized PDA/PAA-Cu（OH）₂JNPs have a high drug loading capacity,excellent photothermal conversion efficiency,strong NIR absorption and p H/NIR dual response drug release capabilities which are used for chemo-photothermal combined therapy.（2）The acorn-like PAA-mCaP/PDA JNPs based on PAA-Ca nanospheres was prepared via a novel and simple method.Then,PDA domain was selectively functionalized with methoxy polyethylene glycol-thiol（PEG-SH）to obtain a better stability.The mCaP side serves as storage space and channel for anticancer drugs.The obtained acorn-like PAA-mCaP/PDA-PEG JNPs are applied for PA imaging-guided synergistic combination of cancer therapy.The preparation method has universality and can be expanded to synthesize other mesoporous Janus nanomaterials.Hence,the acorn-shaped PAA-mCaP/PDA-PEG JNPs paves the way for the design and synthesis of nanocomposites in nanomedicine,biosensing and catalysis.