Bridged element for detection of a target substance

Abstract

Physical changes resulting from an association between a template molecule and a target molecule are detected by monitoring changes in the template molecule. Exemplary changes include a change in a physical dimension or stiffness of the template molecule, a change in electrical conductivity of the template molecule and a change in the energy required to dissociate the target molecule and the template molecule. The magnitude of the change is indicative of the specific identity of the target molecule.

1 . (canceled) 
     
     
         2 . A system comprising:
 a target molecule introduction port for receiving a sample;   a sensor having a template molecule in communication with the target molecule introduction port and disposed within a flow path, the template molecule linked between a first point on a first surface and a second point on a second surface, the first surface independent of the second surface and wherein the template molecule has at least one recognition site specific to a target molecule, wherein a single stranded conductive nucleic acid molecule is selected as the template molecule;   a detector coupled to the first point and the second point and configured to generate an output signal based on a change in a measured parameter corresponding to an association between the template molecule with the target molecule, wherein the measured parameter is electrical conduction through the template molecule; and   an output circuit to provide a result based on the output signal; and   wherein the template molecule, the first contact point, the detector and the second contact point form an electrical circuit, and further, wherein the detector comprises a driving circuit for providing a current or voltage through the electrical circuit for disassociation of the template molecule from the target molecule.   
     
     
         3 . The system of  claim 2  further including a plurality of sensors, each sensor coupled to the detector by a multiplexer. 
     
     
         4 . The system of  claim 2 , further comprising a processor coupled to the detector and having access to a memory, wherein the memory provides data storage for identifying a target molecule based on the change in the measured parameter. 
     
     
         5 . The system of  claim 2 , wherein the output circuit includes at least one of an interface, a display and a wireless transceiver. 
     
     
         6 . The system of  claim 2  further including a test circuit coupled to the template molecule to determine conductivity of the template molecule. 
     
     
         7 . The system of  claim 2  further including a reset circuit coupled to the template molecule to disbond a target molecule from the template molecule. 
     
     
         8 . The system of  claim 2  further including a housing for containment of at least one of the target molecule introduction port, the sensor, the detector and the output circuit. 
     
     
         9 . The system of  claim 2 , wherein an increase in the first physical parameter corresponds to an association between the target nucleic acid molecule and the template nucleic acid molecule. 
     
     
         10 . The system of  claim 2 , said system comprising multiple flow paths in which said sensors are disposed. 
     
     
         11 . The system of  claim 2 , said system comprising one or more reservoir. 
     
     
         12 . The system of  claim 2 , said system comprising a pumping means. 
     
     
         13 . A method comprising:
 introducing a target molecule into the introduction port of a system of  claim 1  and forming a hybridized nucleic acid molecule;   generating an output signal as a function of a change in a first physical parameter indicative of electrical conduction through the template molecule disposed in said system, said output signal being measured using the first contact point relative to a reference point, wherein the change in the first physical parameter corresponds to an association between the target molecule and the template molecule; and   generating a current or voltage that passes through the first contact point, the template molecule and the second contact point to disassociate the hybridized nucleic acid molecule.   
     
     
         14 . The method of  claim 13  further including:
 monitoring a resonant frequency of the first contact point relative to a reference point; 
 monitoring a resonant amplitude of the first contact point relative to the reference point; 
 monitoring a distance between the first contact point and the reference point; and 
 monitoring an alignment between the first contact point and the reference point. 
 
     
     
         15 . The method of  claim 14 , wherein the reference point includes the second contact point. 
     
     
         16 . The method of  claim 13 , said output signal being selected from impedance, conductivity, resistivity, inductance, and/or capacitance.