Nanoscale electronic detection system and methods for their manufacture
A new, extremely sensitive, and rapid electronic detection method for direct detection of hybridized genomic targets to specific probes on the microarray is proposed. The method consists of fast electronic accumulation of the DNA target on a particular electrode site at the micro-electrode array, sequential electronic hybridization of oligonucleotide labeled metallic (nano)particles on the target DNA and monitoring the electrochemical AC impedance changes at the electrode site. The method is enhanced by electroplating over the DNA target which serves as the metallization template and over the particles which provide seeds for rapid electroplating. The AC impedance changes are monitored during the electroplating over the DNA target and between the array electrodes sites. The signal in the absence and presence of the target DNA is a difference between “no connection” and a “short” between the array electrodes
1 . A method for the electronic detection of hybridized targets comprising the steps of:
providing an electronic microarray having specific probes associated with two or more microarray locations,
electronically accumulate the target on a particular electrode site at the micro-electrode array,
sequential electronic hybridization of oligonucleotide labeled conductive particles on the target, and
monitoring the electrochemical AC impedance changes at the electrode site.
2 . The method of claim 1 wherein the target is a genomic target.
3 . The method of claim 2 wherein the genomic target is a nucleic acid.
4 . The method of claim 3 wherein the nucleic acid is DNA.
5 . The method of claim 3 wherein the nucleic acid is RNA.
6 . The method of claim 1 wherein the particles are nanoparticles.
7 . The method of claim 1 further including the step of electroplating over the DNA target.
8 . The method of claim 4 wherein the target serves as the metallization template.
9 . The method of claim 1 wherein the conductive particles are metallic particles.
10 . The method of claim 9 wherein the metallic particles are gold.
11 . The method of claim 9 wherein the metallic particles are silver.
12 . The method of claim 9 wherein the metallic particles are palladium.