Passive sensor capable of detection of materials including specific dna or dna-like strands

A method for detecting DNA within a sample, comprising:

• transmitting electromagnetic signals from a plurality of transmitter-receivers to a sensor device containing a plurality of sensor elements, wherein the sensor elements are coupled to the plurality of transmitter-receivers such that electromagnetic signals are transmitted by a transmitter-receiver, pass through the sensor elements, and return to either the same or a different transmitter-receiver;
• wherein each sensor element comprises a single-stranded DNA fragment, and said single-stranded DNA fragment of the sensor element is configured to couple to a specific single-stranded DNA fragment from the sample to form a double-stranded DNA fragment, wherein, coupling of a single-stranded DNA fragment from the sample to a corresponding single-stranded DNA fragment from the sensor element causes a physical change in a range of signals that return to the same or a different transmitter-receiver;
• detecting the electromagnetic signals received by the plurality of transmitter-receivers;
• and
• based on whether a particular electromagnetic signal that was sent by a transmitter-receiver is subsequently received by the same or a different transmitter-receiver, determining whether a particular single-stranded DNA fragment from the sample is coupled to a corresponding single-stranded DNA fragment from the sensor element.