Study Of The Adsorption Of DNA Functionalized Prussian Blue And Their Application In Cancer Therapy

Cancer is currently the disease with the highest mortality rate in the world,while lung cancer is one of the malignant tumors with the fastest growing incidence and mortality,and the greatest threat to the health and life.At present,the application of antitumor drugs or small molecules with tumor targeting is one of the relatively safe and effective strategies for tumor treatment.Prussian blue,as a nanomaterial with excellent chemical stability,biocompatibility,catalytic and photothermal properties,can bind to a variety of small molecules,ions and biomarkers,especially to desoxyribonucleic acid（DNA）,making it widely used in biosensing,drug delivery and cancer therapy.Therefore,the fundamental interactions of DNA with the surface of Prussian blue nanoparticles（PBNPs）are crucial for further extensive sensing analysis and practical applications.（1）For the study of the adsorption behavior between PBNPs and DNA,a unique FAM-labeled DNA@PBNPs nanocomposite was constructed and the adsorption and desorption processes between them were explored.It was found that the adsorption kinetics between PBNPs and DNA conformed to Langmuir’s law,and the phosphate backbone of DNA can form Fe（II,III）/PO₄^3-chelates between iron ions located at the vertices of the PBNPs cubes,thereby adsorbing both single-stranded DNA（ss DNA）and double-stranded DNA（ds DNA）.Moreover,the adsorption of PBNPs and DNA with arbitrary sequences makes the results universal.In terms of biosensing,we explored the sensing application of DNA@PBNPs for aptamers and proteins.Due to the strong covalent interaction between DNA and PBNPs,DNA base pairing based on hydrogen bonds cannot achieve efficient sensing,while proteins and aptamers readily form G-quadruplexes between each other,thus enabling desorption with biosensing ability.This study will improve our fundamental understanding of DNA adsorption on PBNPs and facilitate the further development of its sensing applications.（2）We constructed a DNA-functionalized PBNPs nanozyme.In which,DNA not only enhances the catalytic activity of Prussian blue,but also designs specific DNA sequences as aptamers to facilitate specific binding to tumor-targeting ligands for selective targeting and specific delivery.Combined with the photothermal properties of Prussian blue,DNA@PBNPs nanozymes can maximize the precise control of therapeutic effects and reduce the toxic side effects caused by non-specific accumulation on other normal cells,effectively achieving targeted killing of lung cancer cells.This topic not only has the advantages of easy operation and low cost-effectiveness,but also the DNA-functionalized Prussian blue nanozyme has the advantages of strong catalytic ability,good stability and strong anti-interference ability,which has practical application value.