Drexel University

Leversense LLC

Gossett Augustus Campbell

Rajakkannu Mutharasan

David R Maraldo

Kishan Rijal

Peter Nagy

David L Delesdernier

Paul Karl Horan

Detection of miniscule amounts of nucleic acid is accomplished via binding of target nucleic acid to probe material, composed of nucleic acid, which is bound to a sensor configured to sense mass. The sensor is prepared by immobilizing a probe material to a surface of the sensor, wherein the probe material is known to bind to the target nucleic acid. The prepared sensor is exposed to the target nucleic acid. The target nucleic acid binds to the probe material. The mass accumulated on the sensor reflects the amount of target nucleic acid bound to the probe material.

Detection of nucleic acids using a cantilever sensor

Flow cells configured for piezoelectric millimeter-sized cantilever sensors provide direct, sensitive detection of analytes in fluid media. The flow cells comprise a flow inlet and a flow outlet positioned to cause sample flow past a sensing surface of the cantilever sensor. The flow cell is configured for millimeter-sized cantilever sensors. The geometry of the flow cell influences the sample flow and thus the interaction of the flow with the cantilever sensor.

Flow cells for piezoelectric cantilever sensors

A piezoelectric cantilever sensor includes a piezoelectric layer and a non-piezoelectric layer, a portion of which is attached to the piezoelectric layer. In one embodiment, one end of the non-piezoelectric layer extends beyond the end of piezoelectric layer to provide an overhang. The overhang piezoelectric cantilever sensor enables increased sensitivity allowing application of the device in more viscous environments, such as liquid media, as well as application in liquid media at higher flow rates than conventional piezoelectric cantilevers. In another embodiment, the sensor includes first and second bases and at least one of the piezoelectric layer and the non-piezoelectric layer is affixed to each of the first and second bases to form the piezoelectric cantilever sensor. In this embodiment, the sensor is robust and exhibits excellent sensing characteristics in both gaseous and liquid media, even when subjected to relatively high flow rates.

Self-exciting, self-sensing piezoelectric cantilever sensor

Detecting an analyte using a piezoelectric cantilever sensor

A method for detection of airborne biological agent using a piezoelectric cantilever sensor that includes a piezoelectric layer and a non-piezoelectric layer. A recognition entity is placed on one or both of the two layers. The antibody that recognizes and binds to the airborne species may be chemically immobilized on the cantilever sensor surface. In one embodiment, the cantilever sensor is attached to a base at only one end. In another embodiment, the sensor includes first and second bases and at least one of the piezoelectric layer and the non-piezoelectric layer is affixed to each of the first and second bases to form a piezoelectric cantilever beam sensor. In this embodiment, resonance is measured via stress on the piezoelectric layer and it has been demonstrated that such sensors are robust and exhibit excellent sensing characteristics in gaseous media with sufficient sensitivity to detect airborne species at relatively low concentrations.

Self-exciting, self-sensing piezoelectric cantilever sensor for detection of airborne analytes directly in air

The techniques described herein are directed to removing material that has attached to or preventing material from attaching to the surface of a piezoelectric cantilever. The material can be a target material, other, non-target, material that may be weakly bound or attached to the cantilever sensor, or the material may be a combination thereof. Accordingly, the cantilever sensor can be reused, in situ, without degraded detection performance of the cantilever sensor. The techniques may also be utilized to remove all material that has attached to a surface of the cantilever sensor which provides means for reusing the cantilever sensor.

Controlling accumulation of select adsorbers on a piezoelectric cantilever sensor

Detection of miniscule amounts of an analyte is accomplished via multiple bindings of specific materials on a sensor configured to sense mass. The sensor is prepared by immobilizing an antibody to a surface of the sensor, wherein the antibody is known to bind to the analyte. The prepared sensor is exposed to the analyte. The analyte binds to the antibody. The sensor then is exposed to additional antibody, which binds to the analyte. The sensor then can be sequentially exposed to additional antibodies that are known to bind to previously bound antibodies. Each additional binding further increases the effective mass of accumulated material on the sensor. The total effective mass is greater than the mass of the accumulated analyte, thus providing means for detecting extremely minute amounts of analyte. Applications include detection of pathogens and DNA.

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Conshohocken, PA, United States of America

Gossett Augustus Campbell