Preparation Of Multifunctional Nanomaterials Based On Ca₃?PO₄?₂ And Application In Cell Imaging And Drug Delivery

The rapid development of nanoscience and nanotechnology has greatly promoted the widely application of nanomaterials in the field of biology and medicine.In recent years,calcium phosphate(CaP)nanomaterials caused widely attention in biomedical field due to their excellent biocompatibility,biodegradability,and pH-sensitivity.How to combine CaP with other functional nanoparticales into a composite nanoparticle(NP)with good dispersion and appropriate size becomes a difficult problem.we report a simple and reproducible method to prepare Au@C/CaP core-shell NPs.The as-fabricated Au@C/CaP NPs show a excellent drug-loading capacity for chemo-photothermal therapy.Furthermore,it is well known that Au NPs have been employed to realize X-ray computed tomography(CT)imaging.In the following work,we report a one-step synthesis strategy to fabricate uniform FA-Au@PAA-Ca Janus NPs(JNPs)through competitive ligand coordination between FA-poly(ethylene glycol)-thiol(FA-PEG-SH)and calcium polyacrylate(PAA-Ca)on the surface of Au NPs.The as-fabricated nano-sized FA-Au@PAA-Ca JNPs were further employed as templates to selectively grow CaP on the side of the PAA-Ca,leading to formation of the novel multifunctional FA-Au@PAA/CaP JNPs with dual distinguished domains.The exposed Au domains with FA-PEG-SH achieve the high contrast for CT imaging,excellent stability,good biocompatibility as well as cancer cell-specific targeting and the other PAA/CaP domains with mesoporous structure served as a storage space and passage for the anti-cancer drug.It is worth noting that the obtained FA-Au@PAA/CaP JNPs possess competent loading capacity,pH-responsive properties,targeting specificity and high contrast for CT imaging.Furthermore,the novel,facile and reproducible synthetic strategy of FA-Au@PAA-Ca JNPs could be extended to synthesis other kind of Janus NPs for specific applications.