Preparation Of Magnetic Fluorescent Composite Nano-materials For Biomedical Applications

ObjectiveMagnetic nanoparticles and quantum dots were widely attracted by investigater based on special physicochemical property in chemistry,biology,pharmacy,medical science,material and engineering manufacture.In recent years,the study had been profoundly promoted about the fabrication and application of magnetic nanoparticles and quantum dots,and derived amounts of new field.In this work,we synthesized magnetic fluorescent nanocomposites based on Fe₃O₄ nanoparticles and Cd Te QDs,and the amino functional magnetic fluorescent encoded microspheres?AFMFEM?and multifunctional drug nanocarries?MDNs?were fabricated for sub-trace pathogenic DNA and targeted delivery of anti-cancer drug Doxorubicin hydrochloride?DOX?,respectively,and this method provided a basis theory and application of magnetic fluorescent component nanoparticles for the further study.MethodsIn this work,we prepared magnetic fluorescent encoded microspheres based on Fe₃O₄ nanoparticles and two Cd Te quantum dots using reverse microemulsion method,and to establish a novel magnetic fluorescent encoded nanoimmunoassay system combining with sand-wich immunoassay for multicomponent biological assay and separation.A novel nano-drug delivery probe was established based on magnetic fluorescent nanoparticles,then the probe was synthetically evaluated using multimodal imaging technology for dual-modal imaging,distribution,degree drug release,cancer treatment,biocompatibility in cellular level.ResultA new nanoimmunoassay system based on novel magnetic fluorescent encoded microspheres was established,which promised the detection and separation of subtrace pathogenic DNA?Hepatitis A Virus Vall7 Polyprotein gene,HAV and Hepatitis B Virus Surface antigen gene,HBV?.The results of this work showed that it could quantitatively detect the multicomponets trace pathogenic HAV and HBV DNA from 0-120 pM and 0-90 pM and detection limit up to 0.1 pM and 0.12 pM,respectively.A novel multifunctional magnetic fluorescent drug nanocarriers were developed by carboxymethyl chitosan?CMCS?and magnetic fluorescent composite nanoparticles?Fe₃O₄-QDs@SiO₂?.The fromed MDNs showed good loaded content?7.06%?and encapsulation efficiency?76.8%?for DOX.In the study of DOX cumulative release from the MDNs,showing pH-regulated drug release and magnetic targeted properties of multifunctional drug nanocarries?MDNs?.ConclusionIn this work,the producted magnetic fluorescent encoded nanoimmunoassay system can be used in multicomponent biomolecules immunoassay and separation of the other biomolecules based on high sensitivity,low detection limit and easy operation.Meanwhile,the new magnetic fluorescent multifunctional drug nanocarries system can be used in magnetic targeted delivery of the other anti-cancer drugs and cancer treatment based on colloidal stability,good biocompatibility,fluorescence properties and pH-regulated drug release.