Methods and apparatuses for detecting analytes in biological fluid of an animal

1. A method of detecting an analyte comprising the steps of:

providing at least one nanoparticle, wherein the nanoparticle is magnetic;

fixing at least one analyte binding molecule to the at least one nanoparticle to form a nanoparticle complex, the at least one analyte binding molecule being capable of binding an analyte;

introducing the nanoparticle complex into a circulatory system of an animal or biological fluid within the animal;

allowing the analyte to bind to the at least one analyte binding molecule within the animal to form an analyte bound nanoparticle complex;

extracting the analyte bound nanoparticle complex prior to detecting the analyte wherein at least one of the acts of introducing and extracting the nanoparticle complex comprises using a magnetic field to move the nanoparticle complex through the skin of the animal; and

detecting the presence of the analyte.

2. The method of claim 1 , wherein the at least one nanoparticle is selected from the group consisting of: superparamagnetic magnetite (Fe 3 O 4 ), and maghemite (yFe 2 O 3 ) iron oxide nanoparticles.

3. The method of claim 2 , wherein the at least one nanoparticle further comprises one of Co 2+ and Mn 2+ .

4. The method of claim 1 , wherein the at least one nanoparticle has a polyethylene glycol coating.

5. The method of claim 1 , wherein the at least one nanoparticle is coated with a material selected from the group consisting of: polymers, dextran,-polyvinylpyrrolidone, fatty acids, polyvinyl alcohol, polyacrylic acid, polypeptides, phosphorylcholine, poly(d,l-lactide), poly(n-isopropylacrylamid), chitosan and gelatin.

6. The method of claim 1 , wherein the analyte is a glucose, and the at least one analyte binding molecule is one of concanavalin A and a glucose binding protein.

7. The method of claim 1 , wherein the at least one analyte binding molecule is an antibody and the analyte is one of a virus antigen and bacterial antigen.

8. The method of claim 1 , wherein the at least one analyte binding molecule is one of a viral surface protein, cancer cell surface protein and bacterial protein and the analyte is an antibody.

9. The method of claim 1 , wherein introducing the at least one nanoparticle does not require piercing the skin of the animal.

10. The method of claim 1 , further comprising determining a concentration of the analyte.

11. The method of claim 1 , wherein the magnet field is between about 100 Gauss and about 20000 Gauss.

12. The method of claim 1 , further comprising providing the magnetic field using one of a rare earth magnet or an electromagnet.

13. The method of claim 1 wherein the presence of the analyte is detected by one of a nanomechanical resonator, a giant magnetoresistance sensor, and a field flow fractionation technique followed by SQUID magnetometry.

14. The method of claim 1 , wherein the presence of the analyte is detected by ELISA techniques.

15. The method of claim 14 , wherein the detection of the analyte further comprises using chromatographic techniques to elute the analyte prior to using the ELISA techniques.

16. The method of claim 1 , further comprising removing the biologic fluid from an animal and at least one of the acts of introducing and extracting the nanoparticle complex using a magnetic field to move the nanoparticle complex through the biologic fluid.

17. The method of claim 1 , wherein the presence of the analyte is detected by PCR techniques.

18. The method of claim 1 , wherein the at least one nanoparticle is between about 1 nm and about 500 nm in diameter.

19. The method of claim 18 , wherein the at least one nanoparticle is between about 1 nm and about 10 nm in diameter.