Electronic detection of hybridization on nucleic acid arrays

A method of detecting locations on a nucleic acid probe array at which hybridization occurs between targets in a fluid sample and nucleic acid probes disposed on a surface of the nucleic acid probe array, comprising:

• measuring the temperature at a plurality of locations on the surface of the nucleic acid probe array;
• applying energy to the surface of the nucleic acid probe array, thereby causing the temperature at the surface of the nucleic acid probe array to increase;
• and
• detecting a decrease in the rate of temperature change at at least one of the plurality of locations on the nucleic acid probe array, thereby indicating an increased heat capacity caused by latent heat of hybridization between at least one target in the fluid sample and at least one nucleic acid probe disposed on a surface of the nucleic acid probe array.

A method of detecting locations on a nucleic acid probe array at which hybridization occurs between targets in a fluid sample and nucleic acid probes disposed on a surface of the nucleic acid probe array, comprising:

• measuring the temperature at a plurality of locations on the surface of the nucleic acid probe array;
• decreasing the temperature of the surface of the nucleic acid probe array;
• and
• detecting a decrease in the rate of temperature change at at least one of the plurality of locations on the nucleic acid probe array, thereby indicating an increased heat capacity caused by latent heat of hybridization between at least one target in the fluid sample and at least one nucleic acid probe disposed on a surface of the nucleic acid probe array.

A system for detecting locations on a nucleic acid probe array at which hybridization occurs between targets in a fluid sample and nucleic acid probes disposed on a surface of the nucleic acid probe array, comprising:

• a nucleic acid probe array;
• at least one heater disposed under the nucleic acid probe array;
• and
• a temperature monitoring system for measuring the temperature at a plurality of locations on the nucleic acid probe array.

A method of detecting locations on a nucleic acid probe array at which hybridization occurs between targets in a fluid sample and nucleic acid probes disposed on a surface of the nucleic acid probe array, comprising:

• positioning an electrode in the target liquid;
• providing an insulating layer under the nucleic acid array;
• providing a n-p-n junction under the insulating layer;
• directing a laser beam at the underside of the n-p-n junction, thereby forming a circuit between the n-p-n junction and the electrode in the target liquid;
• and
• measuring the impedance of the circuit.

A system for detecting locations on a nucleic acid probe array at which hybridization occurs between targets in a fluid sample and nucleic acid probes disposed on a surface of the nucleic acid probe array, comprising:

• an electrode adapted to be disposed in the target liquid;
• an insulating layer disposed under the nucleic acid array;
• and
• a n-p-n junction disposed under the insulating layer.