Patent ID: 7989177

Claim:
An ultrasound-assisted particle agglutination method to detect presence of an analyte in a liquid contained in a resonator cell with an ultrasound transducer acoustically coupled thereto, said resonator cell further containing a plurality of microparticles, each of said microparticles covered with a binding agent with high affinity to said analyte, said method comprising a first phase of exposing said liquid to an ultrasound field at a resonance frequency of said liquid in said cell, said resonance frequency identified by analyzing the electrical impedance of said ultrasound transducer, said exposure causing formation of a nodal pattern and migration of said microparticles to the locations of said nodal pattern creating clusters of said microparticles; said first phase further characterized by formation of specifically- and nonspecifically-bound aggregates of said microparticles in said clusters; said method including a second phase of stirring said liquid with a swept-frequency sonication by varying a driving signal frequency of said transducer in a range from a predefined minimum frequency to a predefined maximum frequency, said predefined minimum and maximum frequencies are selected to include therebetween at least two resonance frequencies of said liquid in said resonator cell as detected by analyzing the electrical impedance of said ultrasound transducer, said stirring causing said nonspecifically-bound aggregates to disintegrate; said method including a third phase of optical or acoustical detection of microparticles aggregates indicating the presence of said analyte in said liquid.