Patent ID: 8067938

Claim:
A detection device, comprising: delivering a sample fluid to a detection device, the detection device comprising: a permanent magnet possessing a field strength of 1-2 Tesla; and . a resonant circuit comprising: a closely wound microcoil, wherein the closely wound microcoil is disposed proximate to a magnetic field generated by the permanent magnet, and wherein the closely wound microcoil is an effective magnetic resonance transmitter or receiver; an auxiliary inductor coil electrically connected in series to the closely wound microcoil; and a tuning capacitor electrically connected to the closely wound microcoil and the auxiliary inductor coil to form a resonant circuit; a capillary with an inner diameter of 100 μm to 400 μm, wherein the closely wound microcoil is woulid around the capillary; and fluid-delivery tubing in fluid communication with the capillary; resonating the resonant circuit at low frequency; and detecting resonance signals from the sample fluid, wherein the resonance signals correlate with a presence of at least one target of interest in the sample fluid.