Magneto-plasmonic biosensing platform for detection of glucose concentration

Abstract

A magneto-optical sensor consisting of [Glass/Au/Co/Au/GS] has been simulated for detection of glucose concentration using a combination of surface plasmon resonance and magneto optical Kerr effect. In this optical sensor, plasmon excitation occurs in the Au thin film and Co plays the role of a magnetic layer. Under optimal conditions of Au and Co thicknesses and incident angle, the magneto-optical transverse Kerr signal is amplified, resulting in an increase in optical sensor sensitivity. In fact, the SPR based sensor evaluates changes in refractive index (RI) of GS. The sensor performance is designed based on two approaches: I) angle shift in the minimum of reflection curve and maximum of transverse Kerr signal in the variable incident angle; II) variation of transverse Kerr signal intensity in a fixed incident angle. Our simulations show that the second approach provides a higher sensitivity, being more applicable due to the performance at a fixed incident angle. This simulated sensor has resolution of 0.003 in the RI value which is equivalent to 0.02 g/ml of glucose concentration. These findings can convey a new pathway to integration of surface plasmon excitation and transverse Kerr effect for sensing applications.