Fabrication Of Functional Chiral Nanoprobe And Disease Analysis

Reactive oxygen species（ROS）play an important role in regulating various physiological functions of living organisms.The excessive production of ROS in the normal body leads to oxidative stress,which is associated with many diseases such as neurodegenerative diseases.Therefore,the detection and homeostasis regulation of reactive oxygen species levels in cells are of great significance for the process of disease.In this study,we constructed a chiral Se@CeO₂nanofunctional probe and a metal-organic framework（Fe-MOF）loaded with chiral Cu_xOS nanoparticles,and established animal models to realize the diagnosis and treatment of Parkinson’s disease and tumors through chiral superparticle enzyme activity and controlled degradation in the tumor microenvironment.Firstly,Se nanoparticles（NPs）with the size of 500 nm and CeO₂NPs with the size of 150nm were synthesized by a one-step method using chiral cysteine as a ligand,and the chiral superparticles with the size of 150 nm,250 nm and 450 nm were obtained by recombination of Se NPs and CeO₂NPs.Circular dichroism spectroscopy was used to characterize the optical activity of Se@CeO₂superparticles with an g-factor value as high as 0.018.The prepared chiral nanofunctional probes showed peroxidase（POD）,glutathione peroxidase（GPx）,catalase（CAT）and superoxide dismutase（SOD）activities.The V_m（maximum reaction rate）of GPx,CAT,and POD of chiral functional nanoprobes（10μg/m L）was 0.99 m M/min,1.54 m M/min,and 3.86×10^-7M/s were 10,7,and 5.6 times higher than that of the mixture of equal amounts of Se NPs and CeO₂NPs.Chiral nanofunctional probes can effectively remove intracellular reactive oxygen species（ROS）by simulating the activities of four enzymes and catalyse the anti-ROS cascade.After 14 days of injection of Se@CeO₂into the brain of the model mice,the motor dysfunction of the Parkinson’s disease model mice was effectively improved,and the content ofα-synuclein in the brain of the mice decreased by 70.7%within 2 weeks.Second,chiral Cu_xOS NPs with a scale of 5 nm were prepared using chiral penicillamine as a ligand using an aqueous phase REDOX method.Using the hydrothermal method,Fe-MOF with a scale of 140 nm was prepared.Then the MOF encapsulation presynthetic nanoparticle method was used to compound Cu_xOS with Fe-MOF to produce chiral Cu_xOS@Fe-MOF nanoparticles with a scale of 150 nm and a circular dichroic response at 404 nm,488 nm,and560 nm.High GSH concentration and low p H both act as stimuli to induce the degradation of NPS,thereby mediating the release of Cu and Fe ions into tumor cells.The controlled degradation of the chiral nanoparticles in tumors was used to induce cupreptosis and ferroptosis in tumor cells,and efficient tumor therapy was achieved.Tumor clearance was as high as 80%within 14 days.From the above,two kinds of chiral nanofunctional probes are prepared,which realize the effective diagnosis and treatment of Parkinson’s disease and tumors,and are expected to provide help for clinical diagnosis and treatment analysis.