Metal Ion Coordinated Polydopamine Nanoparticles And Their Antitumor Applications

Polyphenols(such as dopamine,catechins,tannic acid,and gallic acid)are a class of compounds that widely exist in animals and plants.They are highly valued due to their unique physical and chemical properties,rich sources,and various biological functions(such as anti-tumor,antioxidant,antibacterial,and antiviral activities).Polyphenols can be combined with various substances through hydrogen bonds and hydrophobic interactions between molecules,combined with boronic acid groups or aldehyde groups through dynamic covalent bonds,or combined with metal ions through coordination.Metal ions are ubiquitous in nature and play an important role in the assembly of functional materials in fields such as chemistry,biology,and materials science.An increasing number of researchers have conducted in-depth studies on metal-polyphenol systems.According to reports,various metal-polyphenol systems have played important roles in the field of biomedicine such as anti-tumor(photothermal therapy,photodynamic therapy,chemical dynamic therapy,chemotherapy,etc.)and biological imaging(photoacoustic imaging,nuclear magnetic resonance imaging,fluorescence imaging,etc.).Based on this,we introduce metal ions into the polyphenol-based nanomaterial system,construct metal-polyphenol-based nanomaterials through a simple molecular assembly method,and explore their applications in the field of integrated diagnosis and treatment of anti-tumor.The main research contents are as follows:(1)Uniform and monodisperse PDA@Fe nanoparticles were prepared by a one-step method using dopamine oxidation self-polymerization reaction and metal coordination.The nanoparticles have good photothermal conversion performance and are superior to pure polydopamine nanoparticles.In the acidic tumor microenvironment,it can achieve synergistic treatment of chemical kinetics therapy and photothermal therapy to enhance the anti-tumor treatment effect.The system can also be used as a diagnostic agent for nuclear magnetic resonance imaging and photoacoustic imaging.It shows concentration dependence in water-based dispersion systems.And r1=8.1296 m M-1s-1,r2/r1 is about 1,which can be used as T1-MRI diagnostic agent.This new type of nanomaterial is expected to realize photothermal therapy and chemical kinetics combined treatment guided by nuclear magnetic resonance and photoacoustic dual-mode imaging,providing new ideas for the construction of integrated diagnosis and treatment nanoplatforms for anti-tumor.(2)A novel manganese-coordinated polydopamine-based nanoparticle was constructed by using dopamine and 3,4-dihydroxybenzaldehyde as building blocks through Schiff base reaction and metal coordination.Size-adjustable DA-PA nanoparticles were covalently assembled by Schiff base reaction between dopamine and 3,4-dihydroxybenzaldehyde.Further introduced Mn2+ by coordination to prepare DA-PA@Mn nanoparticles.Various characterization methods such as SEM,EDS,DLS,FTIR,XPS were used to confirm the morphology and composition of the two types of nanoparticles.