Magnetic inorganic iron-based nanoparticles

Abstract

A nanoparticle, which has a metal oxide core and a cerium shell is provided. The weight ratio of the cerium within the shell to the metal oxide in the core is at least 1%. Additionally a method for delivering a ligand into a cell with the nanoparticle is provided. Processes for making the nanoparticle which include: sonicating an aqueous composition containing Ceric Ammonium Nitrate and a prefabricated nanoparticle suspension; and (b) adding a polycationic polymer to the mixture (for NP surface functionalization), are also described

1 - 21 . (canceled) 
     
     
         22 . A composition comprising a metal oxide and cerium, wherein the weight ratio of said cerium to said metal oxide is at least 1%. 
     
     
         23 . A nanoparticle (NP), comprising a core and a shell, wherein said core comprises a metal oxide and said shell comprises cerium, wherein the weight ratio of said cerium within said shell to said metal oxide within said core is at least 1%. 
     
     
         24 . The nanoparticle according to  claim 22 , wherein said nanoparticle has a diameter of 3 to 100 nm. 
     
     
         25 . The nanoparticle according to  claim 23 , wherein said nanoparticle has a positive charge of at least +35.0 mV. 
     
     
         26 . The nanoparticle according to  claim 23 , wherein said nanoparticle has a positive charge of at least +44.0 mV. 
     
     
         27 . The nanoparticle according to  claim 22 , further comprising at least one ligand. 
     
     
         28 . The nanoparticle according to  claim 27 , wherein said ligand is covalently bound to said cerium within said shell. 
     
     
         29 . The nanoparticle according to  claim 27 , wherein said ligand comprises an organic moiety, said organic moiety comprises at least one Lewis basic heteroatom selected from the group consisting of: N, O, and S or any combination of N, O, and S. 
     
     
         30 . The nanoparticle according to  claim 27 , wherein said ligand is a Polyethylenimine (PEI) polymer. 
     
     
         31 . The nanoparticle according to  claim 27 , wherein said ligand is a nucleic acid molecule. 
     
     
         32 . The nanoparticle according to  claim 27 , wherein said ligand is a marker. 
     
     
         33 . A composition comprising the nanoparticle of  claim 22  and a carrier. 
     
     
         34 . A method for delivering a ligand into a cell, comprising the step of contacting said cell with the nanoparticle of  claim 27 . 
     
     
         35 . The method of  claim 34 , wherein said ligand comprises PEI polymer and a nucleic acid molecule and wherein said delivering is transfecting said cell. 
     
     
         36 . A process for making the nanoparticle of  claim 22 , comprising the steps of:
 (a) sonicating an aqueous composition comprising Ceric ammonium Nitrate and a prefabricated nanoparticle suspension, and obtaining a mixture; and   (b) adding a polycationic polymer to said mixture,   thereby, making the nanoparticle of  claim 22 .   
     
     
         37 . The process of  claim 36 , wherein said prefabricated nanoparticle suspension is obtained by: (a) sonicating Iron (II) Chloride tetrahydrate (FeCl 2 .4H 2 O) and Iron(III) chloride hexahydrate (FeCl 3 .6H 2 O); (b) adding aqueous ammonium hydroxide (NH 4 OH); and sonicating the mixture of (a) and (b). 
     
     
         38 . The process of  claim 36 , wherein said Ceric Ammonium Nitrate (CAN) comprises at least 300 mg Ceric Ammonium Nitrate dissolved in at least 12 mL MeCOMe. 
     
     
         39 . The process of  claim 36 , wherein said nanoparticle is obtained by adding a polycationic polymer while said aqueous ammonium hydroxide (NH 4 OH) and said prefabricated nanoparticle suspension are being sonicated. 
     
     
         40 . The process of  claim 36 , wherein said nanoparticle is obtained by adding a polycationic polymer to said mixture of aqueous ammonium hydroxide (NH 4 OH) and said prefabricated nanoparticle suspension after said mixture has been obtained. 
     
     
         41 . The process of  claim 40 , wherein the product of said mixture is a composition of a polymer and polyCOOH organic matter adlayer.