Etched Fiber Bragg Grating Sensor for Quantification of DNA

The detection and quantification of DNA is of critical importance in various molecular biology processes and has applications in fields ranging from forensics to environmental monitoring. Here, the development of a highly sensitive and label-free technique for DNA detection is reported. This article proposes a reduced graphene oxide (rGO) coated etched Fiber Bragg Grating (eFBG) sensor as a tool for the detection and quantification of dsDNA. The proposed sensor is found to have a limit of detection of 261.87 pg/$\mu \text{l}$ and the sensor response is a linear function of the dsDNA concentration in the range between 1 ng/$\mu \text{l}$ to 50 ng/$\mu \text{l}$ with excellent stability and repeatability. The paper also proposes a technique to quantitatively measure the amount of DNA bound to the sensor and thus, the DNA binding efficacy of the rGO coating on the sensor, utilizing UV spectrometry.