Magnetic resonance system and method to detect and confirm analytes

摘要

A system and method are provided to detect target analytes based on magnetic resonance measurements. Magnetic structures produce distinct magnetic field regions having a size comparable to the analyte. When the analyte is bound in those regions, magnetic resonance signals from the sample are changed, leading to detection of the analyte.

主权项

1. A method, for detecting an analyte, comprising the steps of:
a) mixing a sample containing the analyte with paramagnetic nanoparticles comprising an analyte binding agent, in a known liquid comprising non-zero-spin nuclei, thereby forming a mixture, wherein the analyte binding agent can bind to the analyte in the known liquid to form paramagnetic nanoparticle-analyte complexes; b) enhancing binding of the paramagnetic nanoparticles comprising an analyte binding agent to the analyte in the mixture by applying an external, non-uniform magnetic field that varies throughout the volume of the known liquid and has maximal field strength in a subvolume of the known liquid, wherein the paramagnetic nanoparticles and paramagnetic nanoparticle-analyte complexes are drawn into the subvolume by the non-uniform magnetic field, thereby concentrating the paramagnetic nanoparticles and paramagnetic nanoparticle analyte complexes and enhancing interactions therebetween, except that the non-uniform magnetic field is not applied when the T2 magnetic resonance spin relaxation property measurement is being made; and c) measuring a magnetic resonance spin relaxation property of the mixture by:
i) applying an external uniform magnetic field to the mixture;ii) applying one or more radio frequency energy pulses to the mixture in the uniform magnetic field to reorient the bulk magnetization vector of the non-zero spin nuclei in the mixture; andiii) detecting the magnetic resonance spin relaxation property of the mixture, wherein the magnetic resonance spin relaxation property is the spin-spin relaxation time (T2); wherein a change in T2 in the presence of the analyte compared to the T2 of a negative control mixture that does not include analyte indicates the presence of analyte in the sample, thereby detecting the analyte.