Detection of an Epstein-Barr genome analog at physiological concentrations via the biometallization of interdigitated array electrodes.

This paper reports a simple DNA sensor having a detection limit of about 24 oligonucleotides and that operates without the need for PCR amplification. The sensor platform is based on an interdigitated array (IDA) of electrodes. The electrodes are modified with DNA capture probes, which are complementary to an analog for the Epstein-Barr genome, and then exposed to an alkaline phosphatase-labeled target. The enzyme catalyzes the formation of L-ascorbic acid, which reduces Ag(+) in solution to yield conductive Ag filaments that span the gap between the electrodes of the IDA. Resistance measurements, made with an inexpensive, hand-held multimeter, signal the presence of the target. The sensor response is insensitive to the presence of a large excess of non-complementary DNA sequences.