Magnetic Nanoparticles, Magnetically Activated Cell Enrichment, and Biosensing

Executive Summary

Harmful microbes are present in a variety of sources including water, food, plants, environment, and through human-to-human transmission. The ability to detect them rapidly at low cost is important to protecting the health and safety of humans and animals and the security of food chains. MSU researchers have developed novel magnetic nanoparticles for quickly extracting pathogens (bacteria, viruses, fungi, and other microbes) from a variety of complex matrices. This allows enhancing the sensitivity of biosensors and other diagnostics for rapid detection of these pathogens. .

Description of Technology

This technology covers a suite of inventions relating to magnetic nanoparticles, magnetically activated cell enrichment (a.k.a. MACE), a one pot method of making the magnetic nanoparticles, and their use. The particles are based on the synthesis of magnetic Fe₃O₄ nanoparticles covalently coated with glycoconjugates. Examples of glycoconjugates include chitosan, N-acetylglucosamine, cysteine, glycine, mannose, galactose, carboxyl groups, and other glycoproteins, carbohydrates, and their conjugates. Upon mixing with the media containing the target analyte, the glyco-magnetic NPs bind to the microbes which can be selectively separated with a magnet to concentrate them. The concentrated nanoparticle-microbes can then be viewed under a microscope. Identification of specific microbes is done through staining, morphological characterization, or surface charge..

Benefits

Simple method of extracting, concentrating, and detecting bacteria, viruses, and fungi present in a sample
Can be used on multiple media such as sputum, urine, blood, water, food
Eliminates pre-enrichment, purification, pre-treatment steps
Facilitates rapid detection. Improves diagnostic speed in less than one hour
Inexpensive isolation and test method

Applications