Compositions and methods for performing magnetibuoyant separations

Abstract

The methods of the invention employ targeted magnetic particles, preferably targeted nanomagnetic particles, and targeted buoyant particles such as buoyant microparticles and microbubbles. Among the benefits of the invention is the ability to combine targeted magnetic particles with differentially targeted buoyant particles to achieve separation of two or more specifically cell targeted populations during the same work flow.

What is claimed is: 
     
         1 . A kit for separating at least one target biomolecule species from a biological sample, the kit comprising:
 (a) a composition that comprises a targeted magnetic particle species, optionally a targeted nanomagnetic particle species, that targets a first biomolecule species of interest;   (b) a composition that comprises a targeted buoyant particle species, optionally a targeted buoyant microparticle species, optionally a targeted buoyant microbubble species, that targets a second biomolecule species of interest, which composition targets a different biomolecule species as compared to that targeted by the composition comprising the targeted magnetic particle species; and   (c) instructions for separating the at least one target biomolecule species using the targeted magnetic particle species and the targeted buoyant particle species.   
     
     
         2 . The kit according to  claim 1 , wherein the kit comprises a plurality of targeted magnetic particle species, wherein the biomolecule species of interest targeted by each targeted magnetic particle species is different from other biomolecule species of interest targeted by other targeted magnetic particle species and targeted buoyant microparticle species in the kit, wherein the different targeted magnetic particle species are in the same or different compositions in the kit. 
     
     
         3 . The kit according to  claim 1 , wherein the kit comprises a plurality of targeted buoyant particle species, wherein the biomolecule species of interest targeted by each targeted buoyant particle species is different from other biomolecule species of interest targeted by other targeted magnetic particle species and targeted buoyant particle species in the kit, wherein the different targeted buoyant particle species are in the same or different compositions in the kit. 
     
     
         4 . The kit according to  claim 1 , wherein the targeted magnetic particle species is a targeted nanomagnetic particle species that comprises:
 (i) a magnetic core particle;   (ii) a glass layer encapsulating the magnetic core particle;   (iii) a protein/polymer composite layer bound to the glass layer; and   (iv) a targeting moiety that targets the first biomolecule species of interest and comprises one member of a bioaffinity ligand pair bound to the protein/polymer composite layer.   
     
     
         5 . The kit according to  claim 4 , wherein the magnetic core particle of the targeted nanomagnetic particle species comprises magnetite (Fe 3 O 4 ) crystal, optionally wherein the magnetite crystals have a diameter ranging from about 5 nm to about 300 nm. 
     
     
         6 . The kit according to  claim 4 , wherein the glass layer of the targeted nanomagnetic particle species is a silane layer formed from organofunctional alkoxysilane molecules, optionally organofunctional alkoxysilane molecules that comprise a couplable end group, optionally a couplable end group selected from the group consisting of an amino, sulphydryl, carboxyl, and hydroxyl end group. 
     
     
         7 . The kit according to  claim 4 , wherein the protein/polymer composite layer of the targeted nanomagnetic particle species is covalently bound to the glass layer, optionally wherein the protein/polymer composite layer is comprised of serum albumin, optionally bovine or human serum albumin, dextran or casein and wherein optionally the protein/polymer composite layer is permanently bound by heating the composition from about 45° C. to about 85° C.