Patent ID: 8836334
Filing Date: 2014-09-16
Classification: A61B,G01N,G01R

Abstract:
1. A nuclear magnetic resonance system for assessing the presence or concentration of an analyte contained in a body fluid of a mammal in-vivo, the system comprising: (a) a conduit having an inlet for receiving the body fluid (b) a sensor suitable for partial or complete implantation within the mammal's body, the sensor comprising structure defining a sample volume and a port, the sample volume containing magnetic particles having binding moieties which bind said analyte, and the port allowing the analyte to enter the sample volume and preventing, partly or completely, the magnetic particles from leaving the sample volume; (c) a magnetic field detector for detecting the strengths of a magnetic field within or adjacent to the sample volume and a transmitter for transmitting a signal indicative of the strength of the magnetic field; (d) a magnet or magnetic field generator; (e) logic circuitry for calculating a Larmor frequency within said sample volume, or portion thereof, based on the detected strength of the magnetic field; (f) a radiofrequency coil for applying a radiofrequency pulse sequence at or near the calculated Larmor frequency to the sample volume in the presence of a magnetic field provided by the magnet or magnetic field generator to induce echo radiofrequency signals; and (g) a reader for disposition outside the mammal's body comprising a receiver for receiving the signal indicative of the strength of the magnetic field and logic circuitry for assessing the agglomeration of said magnetic particles from the induced echo radiofrequency signals; wherein binding of said magnetic particles to said analyte changes the agglomeration of said magnetic particles such that the extent of aggregation of the magnetic particles is indicative of the presence or concentration of said analyte in said sample volume.