DNA biosensor and methods for making and using the same

Disclosed herein are biosensors and methods for making and using the same. In one embodiment, the sensor for detecting an analyte comprises: a substrate, recognition elements specific for the analyte, an excitation source, a detector, a chamber located between the substrate and the excitation source and between the substrate and the detector, and an emission filter. The recognition elements are tethered to the substrate such that the recognition elements can be exposed to a sample. The excitation source is capable of emitting a first light having a first light peak intensity at a first wavelength, wherein the first light can excite a luminophore to emit a second light when the recognition elements interact with the analyte. The detector is capable of detecting the second light emitted by the luminophore. The emission filter is capable of filtering in a band gap that includes the first light peak intensity.